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Lu W, Xiao J, Gao H, Jia Q, Li Z, Liang J, Xing Q, Mao D, Li H, Chu X, Chen H, Guo H, Han G, Zhao B, Chen L, Lai DYF, Liu S, Lin G. Carbon fluxes of China's coastal wetlands and impacts of reclamation and restoration. Glob Chang Biol 2024; 30:e17280. [PMID: 38613249 DOI: 10.1111/gcb.17280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 03/11/2024] [Accepted: 03/23/2024] [Indexed: 04/14/2024]
Abstract
Coastal wetlands play an important role in regulating atmospheric carbon dioxide (CO2) concentrations and contribute significantly to climate change mitigation. However, climate change, reclamation, and restoration have been causing substantial changes in coastal wetland areas and carbon exchange in China during recent decades. Here we compiled a carbon flux database consisting of 15 coastal wetland sites to assess the magnitude, patterns, and drivers of carbon fluxes and to compare fluxes among contrasting natural, disturbed, and restored wetlands. The natural coastal wetlands have the average net ecosystem exchange of CO2 (NEE) of -577 g C m-2 year-1, with -821 g C m-2 year-1 for mangrove forests and -430 g C m-2 year-1 for salt marshes. There are pronounced latitudinal patterns for carbon dioxide exchange of natural coastal wetlands: NEE increased whereas gross primary production (GPP) and respiration of ecosystem decreased with increasing latitude. Distinct environmental factors drive annual variations of GPP between mangroves and salt marshes; temperature was the dominant controlling factor in salt marshes, while temperature, precipitation, and solar radiation were co-dominant in mangroves. Meanwhile, both anthropogenic reclamation and restoration had substantial effects on coastal wetland carbon fluxes, and the effect of the anthropogenic perturbation in mangroves was more extensive than that in salt marshes. Furthermore, from 1980 to 2020, anthropogenic reclamation of China's coastal wetlands caused a carbon loss of ~3720 Gg C, while the mangrove restoration project during the period of 2021-2025 may switch restored coastal wetlands from a carbon source to carbon sink with a net carbon gain of 73 Gg C. The comparison of carbon fluxes among these coastal wetlands can improve our understanding of how anthropogenic perturbation can affect the potentials of coastal blue carbon in China, which has implications for informing conservation and restoration strategies and efforts of coastal wetlands.
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Affiliation(s)
- Weizhi Lu
- College of the Life and Environment Science, Central South University of Forestry and Technology, Changsha, China
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha, China
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, New Hampshire, USA
| | - Haiqiang Gao
- College of the Life and Environment Science, Central South University of Forestry and Technology, Changsha, China
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha, China
| | - Qingyu Jia
- Institute of Atmospheric Environment, China Meteorological Administration, Shenyang, China
| | - Zhengjie Li
- College of the Life and Environment Science, Central South University of Forestry and Technology, Changsha, China
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha, China
| | - Jie Liang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China
| | - Qinghui Xing
- Key Laboratory for Ecological Environment in Coastal Areas, National Marine Environmental Monitoring Center, Dalian, China
| | - Dehua Mao
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Hong Li
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, and Institute of Eco-Chongming (IEC), Fudan University, Shanghai, China
| | - Xiaojing Chu
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Hui Chen
- College of Life Science, Yangtze University, Jingzhou, China
| | - Haiqiang Guo
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, and Institute of Eco-Chongming (IEC), Fudan University, Shanghai, China
| | - Guangxuan Han
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Bin Zhao
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, and Institute of Eco-Chongming (IEC), Fudan University, Shanghai, China
| | - Luzhen Chen
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Derrick Y F Lai
- Department of Geography and Resource Management, and Centre for Environmental Policy and Resource Management, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Shuguang Liu
- College of the Life and Environment Science, Central South University of Forestry and Technology, Changsha, China
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha, China
| | - Guanghui Lin
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China
- Institute of Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, China
- Hainan International Blue Carbon Research Center, Hainan Research Academy of Environmental Sciences, Haikou, China
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Coleman MA. Algae in the Anthropocene: Managing, conserving, and utilizing algae in an era of rapid environmental change. J Phycol 2024; 60:1-3. [PMID: 38010276 DOI: 10.1111/jpy.13409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The Anthropocene is defined as the current period in which humans have had a large influence over the status and trajectory of earth's climate and environment. Human-induced climate change, pollution, and coastal development have caused major changes to algal persistence, distribution, diversity, and function. This has not only brought new challenges for managing and conserving algae, but also new opportunities. This series of perspective pieces will touch on some of these challenges, potential solutions, and knowledge gaps that we must consider in supporting and understanding algae in the Anthropocene.
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Affiliation(s)
- Melinda A Coleman
- NSW Department of Primary Industries, National Marine Science Centre, Coffs Harbour, New South Wales, Australia
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
- School of Biological Sciences & UWA Oceans Institute, Crawley, Western Australia, Australia
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3
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Lu Z, Qin G, Gan S, Liu H, Macreadie PI, Cheah W, Wang F. Blue carbon sink capacity of mangroves determined by leaves and their associated microbiome. Glob Chang Biol 2024; 30:e17007. [PMID: 37916453 DOI: 10.1111/gcb.17007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 08/17/2023] [Accepted: 10/08/2023] [Indexed: 11/03/2023]
Abstract
Mangroves play a globally significant role in carbon capture and storage, known as blue carbon ecosystems. Yet, there are fundamental biogeochemical processes of mangrove blue carbon formation that are inadequately understood, such as the mechanisms by which mangrove afforestation regulates the microbial-driven transfer of carbon from leaf to below-ground blue carbon pool. In this study, we addressed this knowledge gap by investigating: (1) the mangrove leaf characteristics using state-of-the-art FT-ICR-MS; (2) the microbial biomass and their transformation patterns of assimilated plant-carbon; and (3) the degradation potentials of plant-derived carbon in soils of an introduced (Sonneratia apetala) and a native mangrove (Kandelia obovata). We found that biogeochemical cycling took entirely different pathways for S. apetala and K. obovata. Blue carbon accumulation and the proportion of plant-carbon for native mangroves were high, with microbes (dominated by K-strategists) allocating the assimilated-carbon to starch and sucrose metabolism. Conversely, microbes with S. apetala adopted an r-strategy and increased protein- and nucleotide-biosynthetic potentials. These divergent biogeochemical pathways were related to leaf characteristics, with S. apetala leaves characterized by lower molecular-weight, C:N ratio, and lignin content than K. obovata. Moreover, anaerobic-degradation potentials for lignin were high in old-aged soils, but the overall degradation potentials of plant carbon were age-independent, explaining that S. apetala age had no significant influences on the contribution of plant-carbon to blue carbon. We propose that for introduced mangroves, newly fallen leaves release nutrient-rich organic matter that favors growth of r-strategists, which rapidly consume carbon to fuel growth, increasing the proportion of microbial-carbon to blue carbon. In contrast, lignin-rich native mangrove leaves shape K-strategist-dominated microbial communities, which grow slowly and store assimilated-carbon in cells, ultimately promoting the contribution of plant-carbon to the remarkable accumulation of blue carbon. Our study provides new insights into the molecular mechanisms of microbial community responses during reforestation in mangrove ecosystems.
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Affiliation(s)
- Zhe Lu
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, P.R. China
- South China National Botanical Garden, Guangzhou, P.R. China
| | - Guoming Qin
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, P.R. China
- University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Shuchai Gan
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, P.R. China
- South China National Botanical Garden, Guangzhou, P.R. China
| | - Hongbin Liu
- Department of Ocean Sciences and Division of Life Sciences, School of Science, Hong Kong University of Science and Technology, Hong Kong, P.R. China
| | - Peter I Macreadie
- School of Life and Environmental Sciences, Deakin University, Burwood Campus, Burwood, Victoria, Australia
| | - Wee Cheah
- Institute of Ocean and Earth Sciences, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Faming Wang
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, P.R. China
- South China National Botanical Garden, Guangzhou, P.R. China
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Holmquist JR, Klinges D, Lonneman M, Wolfe J, Boyd B, Eagle M, Sanderman J, Todd-Brown K, Belshe EF, Brown LN, Chapman S, Corstanje R, Janousek C, Morris JT, Noe G, Rovai A, Spivak A, Vahsen M, Windham-Myers L, Kroeger K, Megonigal JP. The Coastal Carbon Library and Atlas: Open source soil data and tools supporting blue carbon research and policy. Glob Chang Biol 2024; 30:e17098. [PMID: 38273507 DOI: 10.1111/gcb.17098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/20/2023] [Accepted: 11/20/2023] [Indexed: 01/27/2024]
Abstract
Quantifying carbon fluxes into and out of coastal soils is critical to meeting greenhouse gas reduction and coastal resiliency goals. Numerous 'blue carbon' studies have generated, or benefitted from, synthetic datasets. However, the community those efforts inspired does not have a centralized, standardized database of disaggregated data used to estimate carbon stocks and fluxes. In this paper, we describe a data structure designed to standardize data reporting, maximize reuse, and maintain a chain of credit from synthesis to original source. We introduce version 1.0.0. of the Coastal Carbon Library, a global database of 6723 soil profiles representing blue carbon-storing systems including marshes, mangroves, tidal freshwater forests, and seagrasses. We also present the Coastal Carbon Atlas, an R-shiny application that can be used to visualize, query, and download portions of the Coastal Carbon Library. The majority (4815) of entries in the database can be used for carbon stock assessments without the need for interpolating missing soil variables, 533 are available for estimating carbon burial rate, and 326 are useful for fitting dynamic soil formation models. Organic matter density significantly varied by habitat with tidal freshwater forests having the highest density, and seagrasses having the lowest. Future work could involve expansion of the synthesis to include more deep stock assessments, increasing the representation of data outside of the U.S., and increasing the amount of data available for mangroves and seagrasses, especially carbon burial rate data. We present proposed best practices for blue carbon data including an emphasis on disaggregation, data publication, dataset documentation, and use of standardized vocabulary and templates whenever appropriate. To conclude, the Coastal Carbon Library and Atlas serve as a general example of a grassroots F.A.I.R. (Findable, Accessible, Interoperable, and Reusable) data effort demonstrating how data producers can coordinate to develop tools relevant to policy and decision-making.
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Affiliation(s)
| | - David Klinges
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
- University of Florida, Gainesville, Florida, USA
| | - Michael Lonneman
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
| | - Jaxine Wolfe
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
| | | | | | | | | | - E Fay Belshe
- University of Florida, Gainesville, Florida, USA
| | - Lauren N Brown
- Bowling Green State University, Bowling Green, Ohio, USA
| | | | | | | | - James T Morris
- University of South Carolina, Columbia, South Carolina, USA
| | - Gregory Noe
- USGS, Wetland Ecosystem Ecology and Biogeochemistry Laboratory, Reston, Virginia, USA
| | - André Rovai
- Louisiana State University, Baton Rouge, Louisiana, USA
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Fan B, Li Y. China's conservation and restoration of coastal wetlands offset much of the reclamation-induced blue carbon losses. Glob Chang Biol 2024; 30:e17039. [PMID: 37987506 DOI: 10.1111/gcb.17039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 10/21/2023] [Accepted: 10/26/2023] [Indexed: 11/22/2023]
Abstract
China's coastal wetlands have experienced large losses and gains with rapid coastal reclamation and restoration since the end of the 20th century. However, owing to the difficulties in mapping soil organic carbon (SOC) in blue carbon stocks of coastal wetlands on a national scale, little is known about the spatial pattern of SOC stock in China's coastal wetlands and the loss and gain of SOC stock following coastal reclamation, conservation, and restoration over the past decades. Here, we developed a SOC stock map in China's coastal wetlands at 30 m spatial resolution, analyzed the spatial variability and driving factors of SOC stocks, and finally estimated SOC losses and gains due to coastal reclamation and wetland management from 1990 to 2020. We found that the total SOC stocks in China's coastal wetlands were 77.8 Tg C by 2020 with 3.6 Tg C in mangroves, 8.8 Tg C in salt marshes, and 65.4 Tg C in mudflats. Temperature, rainfall, and seawater salinity exerted the highest relative contributions to SOC spatial variability. The spatial trend of SOC density gradually decreased from south to north except for Liaoning province, with the lowest density in Shandong province. About 24.9% (19.4 Tg C) of SOC stocks in China's coastal wetlands were lost due to high-intensity reclamation, but SOC stock gained from conservation and restoration offset the reclamation-induced losses by 58.2% (11.3 Tg C) over the past three decades. These findings demonstrated the great potential of conservation and restoration of coastal wetlands in reversing the loss trend of blue carbon and contributing to the mitigation of climate change toward carbon neutrality. Our study provides significant spatial insights into the stocks, sequestration, and recovery capacity of blue carbon following rapid urbanization and management actions, which benefit the progress of global blue carbon management.
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Affiliation(s)
- Bingxiong Fan
- State Key Laboratory of Marine Environmental Science, Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Yangfan Li
- State Key Laboratory of Marine Environmental Science, Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
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6
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Fu C, Li Y, Zeng L, Tu C, Wang X, Ma H, Xiao L, Christie P, Luo Y. Climate and mineral accretion as drivers of mineral-associated and particulate organic matter accumulation in tidal wetland soils. Glob Chang Biol 2024; 30:e17070. [PMID: 38273549 DOI: 10.1111/gcb.17070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 11/03/2023] [Accepted: 11/09/2023] [Indexed: 01/27/2024]
Abstract
Tidal wetlands sequester vast amounts of organic carbon (OC) and enhance soil accretion. The conservation and restoration of these ecosystems is becoming increasingly geared toward "blue" carbon sequestration while obtaining additional benefits, such as buffering sea-level rise and enhancing biodiversity. However, the assessments of blue carbon sequestration focus primarily on bulk SOC inventories and often neglect OC fractions and their drivers; this limits our understanding of the mechanisms controlling OC storage and opportunities to enhance blue carbon sinks. Here, we determined mineral-associated and particulate organic matter (MAOM and POM, respectively) in 99 surface soils and 40 soil cores collected from Chinese mangrove and saltmarsh habitats across a broad range of climates and accretion rates and showed how previously unrecognized mechanisms of climate and mineral accretion regulated MAOM and POM accumulation in tidal wetlands. MAOM concentrations (8.0 ± 5.7 g C kg-1 ) (±standard deviation) were significantly higher than POM concentrations (4.2 ± 5.7 g C kg-1 ) across the different soil depths and habitats. MAOM contributed over 51.6 ± 24.9% and 78.9 ± 19.0% to OC in mangrove and saltmarsh soils, respectively; both exhibited lower autochthonous contributions but higher contributions from terrestrial or marine sources than POM, which was derived primarily from autochthonous sources. Increased input of plant-derived organic matter along the increased temperature and precipitation gradients significantly enriched the POM concentrations. In contrast, the MAOM concentrations depended on climate, which controlled the mineral reactivity and mineral-OC interactions, and on regional sedimentary processes that could redistribute the reactive minerals. Mineral accretion diluted the POM concentrations and potentially enhanced the MAOM concentrations depending on mineral composition and whether the mineral accretion benefited plant productivity. Therefore, management strategies should comprehensively consider regional climate while regulating sediment supply and mineral abundance with engineering solutions to tap the OC sink potential of tidal wetlands.
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Affiliation(s)
- Chuancheng Fu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- Marine Science Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Yuan Li
- CAS Key Laboratory of Coastal Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Lin Zeng
- School of Resources and Environmental Engineering, Ludong University, Yantai, China
| | - Chen Tu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Xiaoli Wang
- CAS Key Laboratory of Coastal Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Haiqing Ma
- CAS Key Laboratory of Coastal Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Leilei Xiao
- CAS Key Laboratory of Coastal Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Peter Christie
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Yongming Luo
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- CAS Key Laboratory of Coastal Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
- University of the Chinese Academy of Sciences, Beijing, China
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Capooci M, Seyfferth AL, Tobias C, Wozniak AS, Hedgpeth A, Bowen M, Biddle JF, McFarlane KJ, Vargas R. High methane concentrations in tidal salt marsh soils: Where does the methane go? Glob Chang Biol 2024; 30:e17050. [PMID: 38273533 DOI: 10.1111/gcb.17050] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 10/18/2023] [Accepted: 10/18/2023] [Indexed: 01/27/2024]
Abstract
Tidal salt marshes produce and emit CH4 . Therefore, it is critical to understand the biogeochemical controls that regulate CH4 spatial and temporal dynamics in wetlands. The prevailing paradigm assumes that acetoclastic methanogenesis is the dominant pathway for CH4 production, and higher salinity concentrations inhibit CH4 production in salt marshes. Recent evidence shows that CH4 is produced within salt marshes via methylotrophic methanogenesis, a process not inhibited by sulfate reduction. To further explore this conundrum, we performed measurements of soil-atmosphere CH4 and CO2 fluxes coupled with depth profiles of soil CH4 and CO2 pore water gas concentrations, stable and radioisotopes, pore water chemistry, and microbial community composition to assess CH4 production and fate within a temperate tidal salt marsh. We found unexpectedly high CH4 concentrations up to 145,000 μmol mol-1 positively correlated with S2- (salinity range: 6.6-14.5 ppt). Despite large CH4 production within the soil, soil-atmosphere CH4 fluxes were low but with higher emissions and extreme variability during plant senescence (84.3 ± 684.4 nmol m-2 s-1 ). CH4 and CO2 within the soil pore water were produced from young carbon, with most Δ14 C-CH4 and Δ14 C-CO2 values at or above modern. We found evidence that CH4 within soils was produced by methylotrophic and hydrogenotrophic methanogenesis. Several pathways exist after CH4 is produced, including diffusion into the atmosphere, CH4 oxidation, and lateral export to adjacent tidal creeks; the latter being the most likely dominant flux. Our findings demonstrate that CH4 production and fluxes are biogeochemically heterogeneous, with multiple processes and pathways that can co-occur and vary in importance over the year. This study highlights the potential for high CH4 production, the need to understand the underlying biogeochemical controls, and the challenges of evaluating CH4 budgets and blue carbon in salt marshes.
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Affiliation(s)
- Margaret Capooci
- Department of Plant and Soil Science, University of Delaware, Newark, Delaware, USA
| | - Angelia L Seyfferth
- Department of Plant and Soil Science, University of Delaware, Newark, Delaware, USA
| | - Craig Tobias
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA
| | - Andrew S Wozniak
- School of Marine Science and Policy, University of Delaware, Lewes, Delaware, USA
| | - Alexandra Hedgpeth
- Department of Geography, University of California, Los Angeles, Los Angeles, California, USA
- Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Malique Bowen
- School of Marine Science and Policy, University of Delaware, Lewes, Delaware, USA
| | - Jennifer F Biddle
- School of Marine Science and Policy, University of Delaware, Lewes, Delaware, USA
| | - Karis J McFarlane
- Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Rodrigo Vargas
- Department of Plant and Soil Science, University of Delaware, Newark, Delaware, USA
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Hamylton S, Kelleway J, Rogers K, McLean R, Tynan ZN, Repina O. Mangrove expansion on the low wooded islands of the Great Barrier Reef. Proc Biol Sci 2023; 290:20231183. [PMID: 37909075 PMCID: PMC10618860 DOI: 10.1098/rspb.2023.1183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 09/28/2023] [Indexed: 11/02/2023] Open
Abstract
Mangrove forests are the dominant vegetation growing on low wooded islands, which occur in the Caribbean, Indian and Pacific Oceans. In the northern Great Barrier Reef, we map remarkable, undocumented mangrove forest extension on 10 low wooded islands in the Howick Group that collectively equates to an area of 667 000 m2 (66.7 ha). We combine extensive field survey with canopy height models derived from RPA imagery and allometric scaling to quantify above ground biomass in both old (pre-1973) and new (post-1973) forest areas. Forest expansion added approximately 10 233 tonnes of new biomass since the early 1970s. We suggest that such substantial expansion of mangrove forest has occurred within a short time span in response to changing environmental controls. These may include sea-level rise, sediment transport and deposition, cyclone impact and the development of associated reef flat sedimentary landforms including unconsolidated and lithified shingle ridges, which influence reef flat hydrodynamics. Our observations highlight the globally dynamic response of mangrove distribution and forest structure to environmental change and provide timely new estimates from understudied reef island settings.
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Affiliation(s)
- Sarah Hamylton
- School of Earth, Atmospheric and Life Sciences, University of Wollongong Faculty of Science Medicine and Health, Wollongong, New South Wales 2522, Australia
| | - Jeff Kelleway
- School of Earth, Atmospheric and Life Sciences, University of Wollongong Faculty of Science Medicine and Health, Wollongong, New South Wales 2522, Australia
| | - Kerrylee Rogers
- School of Earth, Atmospheric and Life Sciences, University of Wollongong Faculty of Science Medicine and Health, Wollongong, New South Wales 2522, Australia
| | - Roger McLean
- University of New South Wales, Sydney, New South Wales, Australia
| | - Zachary Nagel Tynan
- School of Earth, Atmospheric and Life Sciences, University of Wollongong Faculty of Science Medicine and Health, Wollongong, New South Wales 2522, Australia
| | - Oxana Repina
- School of Earth, Atmospheric and Life Sciences, University of Wollongong Faculty of Science Medicine and Health, Wollongong, New South Wales 2522, Australia
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Wang T, Chuai XW, Xiang A, Gu YJ, Bie M. Carbon budget and evaluation of marine industry in Jiangsu Province, China. Ying Yong Sheng Tai Xue Bao 2023; 34:2527-2535. [PMID: 37899120 DOI: 10.13287/j.1001-9332.202309.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
The measurement and evaluation of carbon budget of marine industry is the basis for promoting green and efficient development of marine economy under the goal of carbon neutrality. We constructed a carbon accounting system for the marine industry in Jiangsu Province, and assessed carbon efficiency and neutrality. The results showed that from 2016 to 2020, the total amount of marine carbon sinks in Jiangsu Province were 894.8 to 2773.2 thousand tons, while carbon emissions of major marine industries were 3538.4 to 4350.6 thousand tons. The net emissions of marine industries ranged from 1478.7 to 2906.1 thousand tons. Both of carbon sinks and emissions were significantly increased in this period. In terms of carbon sinks, the offshore wind power accounted for the largest contribution, followed by ecosystem carbon sequestration, and mariculture carbon sequestration was the smallest. In terms of carbon emissions, the marine transportation industry played a dominant role, followed by coastal tourism and marine fisheries, while the marine engineering and construction industry and marine shipping industry accounted for a small proportion. In general, the carbon neutral status showed that marine industry in Jiangsu Province was in carbon deficit from 2016-2020, but the net emissions were decreasing year by year. The net carbon sink efficiency of mariculture in Jiangsu Province was lower than the national level, and carbon efficiency of offshore wind power was stable.
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Affiliation(s)
- Tong Wang
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Xiao-Wei Chuai
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
- Key Laboratory of Carbon Neutralization and Territorial Space Planning of the Ministry of Natural Resources, Nanjing 210023, China
| | - Ai Xiang
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Yun-Juan Gu
- Marine Economic Monitoring and Assessment Center of Jiangsu Pro-vince, Nanjing 210017, China
| | - Meng Bie
- Marine Economic Monitoring and Assessment Center of Jiangsu Pro-vince, Nanjing 210017, China
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10
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Mouillot D, Derminon S, Mariani G, Senina I, Fromentin JM, Lehodey P, Troussellier M. Industrial fisheries have reversed the carbon sequestration by tuna carcasses into emissions. Glob Chang Biol 2023; 29:5062-5074. [PMID: 37401407 DOI: 10.1111/gcb.16823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 03/13/2023] [Accepted: 04/30/2023] [Indexed: 07/05/2023]
Abstract
To limit climate warming to 2°C above preindustrial levels, most economic sectors will need a rapid transformation toward a net zero emission of CO2 . Tuna fisheries is a key food production sector that burns fossil fuel to operate but also reduces the deadfall of large-bodied fish so the capacity of this natural carbon pump to deep sea. Yet, the carbon balance of tuna populations, so the net difference between CO2 emission due to industrial exploitation and CO2 sequestration by fish deadfall after natural mortality, is still unknown. Here, by considering the dynamics of two main contrasting tuna species (Katsuwonus pelamis and Thunnus obesus) across the Pacific since the 1980s, we show that most tuna populations became CO2 sources instead of remaining natural sinks. Without considering the supply chain, the main factors associated with this shift are exploitation rate, transshipment intensity, fuel consumption, and climate change. Our study urges for a better global ocean stewardship, by curbing subsidies and limiting transshipment in remote international waters, to quickly rebuild most pelagic fish stocks above their target management reference points and reactivate a neglected carbon pump toward the deep sea as an additional Nature Climate Solution in our portfolio. Even if this potential carbon sequestration by surface unit may appear low compared to that of coastal ecosystems or tropical forests, the ocean covers a vast area and the sinking biomass of dead vertebrates can sequester carbon for around 1000 years in the deep sea. We also highlight the multiple co-benefits and trade-offs from engaging the industrial fisheries sector with carbon neutrality.
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Affiliation(s)
- David Mouillot
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- Institut Universitaire de France, IUF, Paris, France
| | - Suzie Derminon
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, Gif-sur-Yvette, France
| | - Gaël Mariani
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Inna Senina
- Satellite Oceanography Division, CLS, Toulouse, France
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11
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Chowdhury A, Naz A, Sharma SB, Dasgupta R. Changes in Salinity, Mangrove Community Ecology, and Organic Blue Carbon Stock in Response to Cyclones at Indian Sundarbans. Life (Basel) 2023; 13:1539. [PMID: 37511914 PMCID: PMC10381154 DOI: 10.3390/life13071539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/03/2023] [Accepted: 07/08/2023] [Indexed: 07/30/2023] Open
Abstract
Climate change-induced frequent cyclones are pumping saline seawater into the Sundarbans. Fani, Amphan, Bulbul, and Yaas were the major cyclones that hit the region during 2019-2021. This study represents the changes in the soil parameters, mangrove biodiversity and zonation due to the cyclone surges in the Indian Sundarbans between 2017 and 2021. Increasing tidal water salinity (parts per thousand) trends in both pre-monsoon (21 to 33) and post-monsoon (14 to 19) seasons have been observed between 2017 and 2021. A 46% reduction in the soil organic blue carbon pool is observed due to a 31% increase in soil salinity. Soil organic blue carbon has been calculated by both wet digestion and the elemental analyzer method, which are linearly correlated with each other. A reduction in the available nitrogen (30%) and available phosphorous (33%) in the mangrove soil has also been observed. Salinity-sensitive mangroves, such as Xylocarpus granatum, Xylocarpus moluccensis, Rhizophora mucronata, Bruguiera gymnorrhiza, and Bruguiera cylindrica, have seen local extinction in the sampled population. An increasing trend in relative density of salinity resilient, Avicennia marina, Suaeda maritima, Aegiceras corniculatum and a decreasing trend of true mangrove (Ceriops decandra) has been observed, in response to salinity rise in surface water as well as soil. As is evident from Hierarchical Cluster Analysis (HCA) and the Abundance/Frequency ratio (A/F), the mangrove zonation observed in response to tidal gradient has also changed, becoming more homogeneous with a dominance of A. marina. These findings indicate that cyclone, climate change-induced sea level rise can adversely impact Sustainable Development Goal 13 (climate action), by decreasing organic soil blue carbon sink and Sustainable Development Goal 14 (life below water), by local extinction of salinity sensitive mangroves.
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Affiliation(s)
- Abhiroop Chowdhury
- Jindal School of Environment and Sustainability, O.P. Jindal Global University, Sonipat 131001, India
| | - Aliya Naz
- Jindal School of Liberal Arts and Humanities, O.P. Jindal Global University, Sonipat 131001, India
| | - Seema B Sharma
- Department of Earth and Environmental Science, KSKV Kachchh University, Mundra Road, Bhuj 370001, India
| | - Rajarshi Dasgupta
- School of Public Policy, Indian Institute of Technology, New Delhi 110016, India
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12
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Breithaupt JL, Steinmuller HE, Rovai AS, Engelbert KM, Smoak JM, Chambers LG, Radabaugh KR, Moyer RP, Chappel A, Vaughn DR, Bianchi TS, Twilley RR, Pagliosa P, Cifuentes-Jara M, Torres D. An Improved Framework for Estimating Organic Carbon Content of Mangrove Soils Using loss-on-ignition and Coastal Environmental Setting. Wetlands (Wilmington) 2023; 43:57. [PMID: 37360757 PMCID: PMC10287774 DOI: 10.1007/s13157-023-01698-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 05/05/2023] [Indexed: 06/28/2023]
Abstract
The use of loss on ignition (LOI) measurements of soil organic matter (SOM) to estimate soil organic carbon (OC) content is a decades-old practice. While there are limitations and uncertainties to this approach, it continues to be necessary for many coastal wetlands researchers and conservation practitioners without access to an elemental analyzer. Multiple measurement, reporting, and verification (MRV) standards recognize the need (and uncertainty) for using this method. However, no framework exists to explain the substantial differences among equations that relate SOM to OC; consequently, equation selection can be a haphazard process leading to widely divergent and inaccurate estimates. To address this lack of clarity, we used a dataset of 1,246 soil samples from 17 mangrove regions in North, Central, and South America, and calculated SOM to OC conversion equations for six unique types of coastal environmental setting. A framework is provided for understanding differences and selecting an equation based on a study region's SOM content and whether mineral sediments are primarily terrigenous or carbonate in origin. This approach identifies the positive dependence of conversion equation slopes on regional mean SOM content and indicates a distinction between carbonate settings with mean (± 1 S.E.) OC:SOM of 0.47 (0.002) and terrigenous settings with mean OC:SOM of 0.32 (0.018). This framework, focusing on unique coastal environmental settings, is a reminder of the global variability in mangrove soil OC content and encourages continued investigation of broadscale factors that contribute to soil formation and change in blue carbon settings. Supplementary Information The online version contains supplementary material available at 10.1007/s13157-023-01698-z.
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Affiliation(s)
| | - Havalend E. Steinmuller
- Florida State University Coastal & Marine Lab, St Teresa, FL USA
- Dauphin Island Sea Lab, Dauphin, AL Island
- Stokes School of Marine and Environmental Science, University of South Alabama, Mobile, AL USA
| | - Andre S. Rovai
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA USA
| | | | - Joseph M. Smoak
- School of Geosciences, University of South Florida, St. Petersburg, USA
| | - Lisa G. Chambers
- Department of Biological Sciences, University of Central Florida, Orlando, FL USA
| | - Kara R. Radabaugh
- Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, St. Petersburg, FL USA
| | | | - Amanda Chappel
- Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL USA
| | - Derrick R. Vaughn
- Dept. of Geological Sciences, University of Florida, Gainesville, FL USA
- School of the Environment, Yale University, 195 Prospect St, New Haven, CT 06511 USA
| | - Thomas S. Bianchi
- Dept. of Geological Sciences, University of Florida, Gainesville, FL USA
| | - Robert R. Twilley
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA USA
| | - Paulo Pagliosa
- Universidade Federal de Santa Catarina, Florianópolis, 88040-900 SC Brasil
| | - Miguel Cifuentes-Jara
- Conservation International, 2011 Crystal Dr., Ste. 600, Arlington, VA USA
- CATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Danilo Torres
- CATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
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13
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Arnaud M, Krause S, Norby RJ, Dang TH, Acil N, Kettridge N, Gauci V, Ullah S. Global mangrove root production, its controls and roles in the blue carbon budget of mangroves. Glob Chang Biol 2023; 29:3256-3270. [PMID: 36994691 DOI: 10.1111/gcb.16701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 03/17/2023] [Indexed: 05/16/2023]
Abstract
Mangroves are among the most carbon-dense ecosystems worldwide. Most of the carbon in mangroves is found belowground, and root production might be an important control of carbon accumulation, but has been rarely quantified and understood at the global scale. Here, we determined the global mangrove root production rate and its controls using a systematic review and a recently formalised, spatially explicit mangrove typology framework based on geomorphological settings. We found that global mangrove root production averaged ~770 ± 202 g of dry biomass m-2 year-1 globally, which is much higher than previously reported and close to the root production of the most productive tropical forests. Geomorphological settings exerted marked control over root production together with air temperature and precipitation (r2 ≈ 30%, p < .001). Our review shows that individual global changes (e.g. warming, eutrophication, drought) have antagonist effects on root production, but they have rarely been studied in combination. Based on this newly established root production rate, root-derived carbon might account for most of the total carbon buried in mangroves, and 19 Tg C lost in mangroves each year (e.g. as CO2 ). Inclusion of root production measurements in understudied geomorphological settings (i.e. deltas), regions (Indonesia, South America and Africa) and soil depth (>40 cm), as well as the creation of a mangrove root trait database will push forward our understanding of the global mangrove carbon cycle for now and the future. Overall, this review presents a comprehensive analysis of root production in mangroves, and highlights the central role of root production in the global mangrove carbon budget.
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Affiliation(s)
- Marie Arnaud
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
- Institute of Ecology and Environmental Sciences Paris (iEES-Paris), Sorbonne University, Paris, France
| | - Stefan Krause
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023, Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Villeurbanne, France
| | - Richard J Norby
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
- Department of Ecology and Evolutionary Biology, University of Tennessee, Tennessee, Knoxville, USA
| | - Thuong Huyen Dang
- Faculty of Geology and Petroleum Engineering, University of Technology, Vietnam National University, Ho Chi Minh City (VNU-HCM), Vietnam
| | - Nezha Acil
- Institute for Environmental Futures, School of Geography, Geology and the Environment, University of Leicester, Space Park Leicester, Leicester, UK
- National Centre for Earth Observation, University of Leicester, Space Park Leicester, Leicester, UK
| | - Nicholas Kettridge
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
| | - Vincent Gauci
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
| | - Sami Ullah
- School of Geography, Earth & Environmental Sciences, University of Birmingham, and Birmingham Institute of Forest Research, Birmingham, UK
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14
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Baustian MM, Liu B, Moss LC, Dausman A, Pahl JW. Climate change mitigation potential of Louisiana's coastal area: Current estimates and future projections. Ecol Appl 2023; 33:e2847. [PMID: 36932861 DOI: 10.1002/eap.2847] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 12/01/2022] [Accepted: 12/20/2022] [Indexed: 06/02/2023]
Abstract
Coastal habitats can play an important role in climate change mitigation. As Louisiana implements its climate action plan and the restoration and risk-reduction projects outlined in its 2017 Louisiana Coastal Master Plan, it is critical to consider potential greenhouse gas (GHG) fluxes in coastal habitats. This study estimated the potential climate mitigation role of existing, converted, and restored coastal habitats for years 2005, 2020, 2025, 2030, and 2050, which align with the Governor of Louisiana's GHG reduction targets. An analytical framework was developed that considered (1) available scientific data on net ecosystem carbon balance fluxes per habitat and (2) habitat areas projected from modeling efforts used for the 2017 Louisiana Coastal Master Plan to estimate the net GHG flux of coastal area. The coastal area was estimated as net GHG sinks of -38.4 ± 10.6 and -43.2 ± 12.0 Tg CO2 equivalents (CO2 e) in 2005 and 2020, respectively. The coastal area was projected to remain a net GHG sink in 2025 and 2030, both with and without the implementation of Coastal Master Plan projects (means ranged from -25.3 to -34.2 Tg CO2 e). By 2050, with model-projected wetland loss and conversion of coastal habitats to open water due to coastal erosion and relative sea level rise, Louisiana's coastal area was projected to become a net source of GHG emissions both with and without the Coastal Master Plan projects. However, in the year 2050, the Louisiana Coastal Master Plan project implementation was projected to avoid the release of +8.8 ± 1.3 Tg CO2 e compared with an alternative with no action. Reduction in current and future stressors to coastal habitats, including impacts from sea level rise, as well as the implementation of restoration projects could help to ensure coastal areas remain a natural climate solution.
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Affiliation(s)
- Melissa M Baustian
- The Water Institute of the Gulf, 1110 River Road South, Suite 200, Baton Rouge, Louisiana, 70802, USA
- U.S. Geological Survey, Wetland and Aquatic Research Center, Baton Rouge, Louisiana, 70808, USA
| | - Bingqing Liu
- The Water Institute of the Gulf, 1110 River Road South, Suite 200, Baton Rouge, Louisiana, 70802, USA
| | - Leland C Moss
- Abt Associates, 6130 Executive Boulevard, Rockville, Maryland, 20852, USA
| | - Alyssa Dausman
- The Water Institute of the Gulf, 1110 River Road South, Suite 200, Baton Rouge, Louisiana, 70802, USA
| | - James W Pahl
- Louisiana Coastal Protection and Restoration Authority, 150 Terrace Avenue, Baton Rouge, Louisiana, 70802, USA
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15
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Wang H, Dai Z, Krauss KW, Trettin CC, Noe GB, Burton AJ, Ward EJ. Modeling impacts of saltwater intrusion on methane and nitrous oxide emissions in tidal forested wetlands. Ecol Appl 2023:e2858. [PMID: 37084186 DOI: 10.1002/eap.2858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 02/14/2023] [Accepted: 04/03/2023] [Indexed: 05/03/2023]
Abstract
Emissions of methane (CH4 ) and nitrous oxide (N2 O) from soils to the atmosphere can offset the benefits of carbon sequestration for climate change mitigation. While past study has suggested that both CH4 and N2 O emissions from tidal freshwater forested wetlands (TFFW) are generally low, the impacts of coastal droughts and drought-induced saltwater intrusion on CH4 and N2 O emissions remain unclear. In this study, a process-driven biogeochemistry model, Tidal Freshwater Wetland DeNitrification-DeComposition (TFW-DNDC) was applied to examine the responses of CH4 and N2 O emissions to episodic drought-induced saltwater intrusion in TFFW along the Waccamaw River and Savannah River, USA. These sites encompass landscape gradients of both surface and porewater salinity as influenced by Atlantic Ocean tides superimposed on periodic droughts. Surprisingly, CH4 and N2 O emission responsiveness to coastal droughts and drought-induced saltwater intrusion varied greatly between river systems and among local geomorphologic settings. This reflected the complexity of wetland CH4 and N2 O emissions and suggests that simple linkages to salinity may not always be relevant, as non-linear relationships dominated our simulations. Along the Savannah River, N2 O emissions in the moderate-oligohaline tidal forest site tended to increase dramatically under the drought condition, while CH4 emission decreased. For the Waccamaw River, emissions of both CH4 and N2 O in the moderate-oligohaline tidal forest site tended to decrease under the drought condition, but the capacity of the moderate-oligohaline tidal forest to serve as a carbon sink was substantially reduced due to significant declines in net primary productivity and soil organic carbon sequestration rates as salinity killed the dominant freshwater vegetation. These changes in fluxes of CH4 and N2 O reflect crucial synergistic effects of soil salinity and water level on C and N dynamics in TFFW due to drought-induced seawater intrusion.
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Affiliation(s)
- Hongqing Wang
- U.S. Geological Survey, Wetland and Aquatic Research Center, Baton Rouge, Louisiana, USA
| | - Zhaohua Dai
- USDA Forest Service, Center for Forested Wetlands Research, Cordesville, South Carolina, USA
- Michigan Technological University, College of Forest Resources and Environmental Science, Houghton, Michigan, USA
| | - Ken W Krauss
- U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, Louisiana, USA
| | - Carl C Trettin
- USDA Forest Service, Center for Forested Wetlands Research, Cordesville, South Carolina, USA
| | - Gregory B Noe
- U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, Virginia, USA
| | - Andrew J Burton
- Michigan Technological University, College of Forest Resources and Environmental Science, Houghton, Michigan, USA
| | - Eric J Ward
- U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, Louisiana, USA
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16
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Li Y, Fu C, Hu J, Zeng L, Tu C, Luo Y. Soil Carbon, Nitrogen, and Phosphorus Stoichiometry and Fractions in Blue Carbon Ecosystems: Implications for Carbon Accumulation in Allochthonous-Dominated Habitats. Environ Sci Technol 2023; 57:5913-5923. [PMID: 36996086 DOI: 10.1021/acs.est.3c00012] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Blue carbon ecosystems (BCEs) including mangroves, saltmarshes, and seagrasses are highly efficient for organic carbon (OC) accumulation due to their unique ability to trap high rates of allochthonous substrates. It has been suggested that the magnitude of OC preservation is constrained by nitrogen (N) and phosphorus (P) limitation in response to climate and anthropogenic changes. However, little is known about the connection of soil OC with N-P and their forms in response to allochthonous inputs in BCEs. By analyzing soil OC, N, and P densities of BCEs from 797 sites globally, we find that, in China, where allochthonous OC provides 50-75% of total OC, soil C/P and N/P ratios are 4- to 8-fold lower than their global means, and 23%, 29%, and 20% of buried OC, N, and P are oxidation-resistant fractions that linked with minerals. We estimate that the OC stocks in China should double over the next 40 years under high allochthonous inputs and elevated N/P ratio scenarios during BCE restoration. Allochthonous-dominated BCEs thus have the capacity to enhance refractory and mineral bound organic matter accumulation. Protection and restoration of such BCEs will provide long-term mitigating benefits against sea level rise and greenhouse gas emissions.
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Affiliation(s)
- Yuan Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, P. R. China
| | - Chuancheng Fu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences (CAS), Nanjing 210008, P. R. China
| | - Jian Hu
- Key Laboratory of Coastal Salt Marsh Ecosystems and Resources, Ministry of Natural Resources, Jiangsu Geological Bureau, Nanjing 210018, P. R. China
| | - Lin Zeng
- School of Resources and Environmental Engineering, Ludong University, Yantai 264025, P. R. China
| | - Chen Tu
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, P. R. China
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences (CAS), Nanjing 210008, P. R. China
| | - Yongming Luo
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, P. R. China
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences (CAS), Nanjing 210008, P. R. China
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17
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Queirós AM, Tait K, Clark JR, Bedington M, Pascoe C, Torres R, Somerfield PJ, Smale DA. Identifying and protecting macroalgae detritus sinks toward climate change mitigation. Ecol Appl 2023; 33:e2798. [PMID: 36504412 DOI: 10.1002/eap.2798] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 08/11/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
Harnessing natural solutions to mitigate climate change requires an understanding of carbon fixation, flux, and sequestration across ocean habitats. Recent studies have suggested that exported seaweed particulate organic carbon is stored within soft-sediment systems. However, very little is known about how seaweed detritus disperses from coastlines, or where it may enter seabed carbon stores, where it could become the target of conservation efforts. Here, focusing on regionally dominant seaweed species, we surveyed environmental DNA (eDNA) from natural coastal sediments, and studied their connectivity to seaweed habitats using a particle tracking model parameterized to reproduce seaweed detritus dispersal behavior based on laboratory observations of seaweed fragment degradation and sinking. Experiments showed that seaweed detritus density changed over time, differently across species. This, in turn, modified distances traveled by released fragments until they reached the seabed for the first time, during model simulations. Dispersal pathways connected detritus from the shore to the open ocean but, importantly, also to coastal sediments, and this was reflected by field eDNA evidence. Dispersion pathways were also affected by hydrodynamic conditions, varying in space and time. Both the properties and timing of released detritus, individual to each macroalgal population, and short-term near-seabed and medium-term water-column transport pathways, are thus seemingly important in determining the connectivity between seaweed habitats and potential sedimentary sinks. Studies such as this one, supported by further field verification of sedimentary carbon sequestration rates and source partitioning, are still needed to help quantify the role of seaweed in the ocean carbon cycle. Such studies will provide vital evidence to inform on the potential need to develop blue carbon conservation mechanisms, beyond wetlands.
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Affiliation(s)
| | - Karen Tait
- Plymouth Marine Laboratory, Plymouth, UK
| | | | | | | | | | | | - Dan A Smale
- Marine Biological Association of the United Kingdom, Plymouth, UK
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18
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Pearson HC, Savoca MS, Costa DP, Lomas MW, Molina R, Pershing AJ, Smith CR, Villaseñor-Derbez JC, Wing SR, Roman J. Whales in the carbon cycle: can recovery remove carbon dioxide? Trends Ecol Evol 2023; 38:238-249. [PMID: 36528413 DOI: 10.1016/j.tree.2022.10.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/04/2022] [Accepted: 10/31/2022] [Indexed: 12/23/2022]
Abstract
The great whales (baleen and sperm whales), through their massive size and wide distribution, influence ecosystem and carbon dynamics. Whales directly store carbon in their biomass and contribute to carbon export through sinking carcasses. Whale excreta may stimulate phytoplankton growth and capture atmospheric CO2; such indirect pathways represent the greatest potential for whale-carbon sequestration but are poorly understood. We quantify the carbon values of whales while recognizing the numerous ecosystem, cultural, and moral motivations to protect them. We also propose a framework to quantify the economic value of whale carbon as populations change over time. Finally, we suggest research to address key unknowns (e.g., bioavailability of whale-derived nutrients to phytoplankton, species- and region-specific variability in whale carbon contributions).
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Affiliation(s)
- Heidi C Pearson
- Department of Natural Sciences, University of Alaska Southeast, Juneau, AK, USA.
| | - Matthew S Savoca
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Daniel P Costa
- Ecology and Evolutionary Biology Department, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Michael W Lomas
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA
| | - Renato Molina
- Rosenstiel School of Marine, Atmospheric, and Earth Science and Miami Herbert Business School, University of Miami, Miami, FL, USA
| | | | - Craig R Smith
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Juan Carlos Villaseñor-Derbez
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA; Bren School of Environmental Science & Management, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Stephen R Wing
- Department of Marine Science, University of Otago, Dunedin, New Zealand
| | - Joe Roman
- Gund Institute for Environment, University of Vermont, Burlington, VT, USA
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19
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Chowdhury A, Naz A, Maiti SK. Variations in Soil Blue Carbon Sequestration between Natural Mangrove Metapopulations and a Mixed Mangrove Plantation: A Case Study from the World's Largest Contiguous Mangrove Forest. Life (Basel) 2023; 13:life13020271. [PMID: 36836629 PMCID: PMC9964440 DOI: 10.3390/life13020271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/27/2022] [Accepted: 01/11/2023] [Indexed: 01/20/2023] Open
Abstract
Sundarban is the world's largest mangrove wetland. This study, conducted in 2016, to compare blue carbon sequestration with different natural metapopulations and a four-year-old Avicennia marina (30% area)-Rhizophora mucronata (70% area)-mixed mangrove plantation under anthropoganic stress. The aims of the study is to find out the variations in soil ecological function indicators (pH, electrical conductivity, bulk density, soil texture, available nitrogn, phosphorus and soil organic carbon) and key ecological service indicator (soil blue carbon pool) between sites. Simpson's Index of dominance, diversity and Shannon-Weiner Index revealed that all the sites are under ecological stress, with the Suaeda maritima-dominated mudflat having the least biodiversity. It is also revealed that pH and electrical conductivity were highest in Suaeda maritima and Phoenix padulosa-dominated metapopulations, whereas organic carbon was the highest under the mangrove plantation and Avicennia marina-dominated site. Available nitrogen was recorded highest in the community with the Sonneretia sp.-Avicennia marina association. The mixed mangrove plantation had the highest blue carbon pool. The species diversity was not found to be related with the distance from the nearby conserved mangrove forest, contrary to the island biogeography theory. This study concludes with a recommendation of mixed mangrove plantations to restore the degraded saline mudflats along the human settlements across the globe.
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Affiliation(s)
- Abhiroop Chowdhury
- Jindal School of Environment and Sustainability, O.P. Jindal Global University, Sonipat 131001, Haryana, India
- Ecological Restoration Laboratory, Department of Environmental Science & Engineering, Indian Institute of Technology (ISM), Dhanbad 826004, Jharkhand, India
- Correspondence:
| | - Aliya Naz
- Jindal School of Liberal Arts and Humanities, O.P. Jindal Global University, Sonipat 131001, Haryana, India
| | - Subodh Kumar Maiti
- Ecological Restoration Laboratory, Department of Environmental Science & Engineering, Indian Institute of Technology (ISM), Dhanbad 826004, Jharkhand, India
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20
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Buck-Wiese H, Andskog MA, Nguyen NP, Bligh M, Asmala E, Vidal-Melgosa S, Liebeke M, Gustafsson C, Hehemann JH. Fucoid brown algae inject fucoidan carbon into the ocean. Proc Natl Acad Sci U S A 2023; 120:e2210561119. [PMID: 36584294 PMCID: PMC9910443 DOI: 10.1073/pnas.2210561119] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/02/2022] [Indexed: 01/01/2023] Open
Abstract
Brown algae annually convert gigatons of carbon dioxide into carbohydrates, including the complex extracellular matrix polysaccharide fucoidan. Due to its persistence in the environment, fucoidan is potentially a pathway for marine carbon sequestration. Rates of fucoidan secretion by brown algae remain unknown due to the challenge of identifying and quantifying complex polysaccharides in seawater. We adapted the techniques of anion exchange chromatography, enzyme-linked immunosorbent assay, and biocatalytic enzyme-based assay for detection and quantification of fucoidan. We found the brown alga Fucus vesiculosus at the Baltic Sea coast of south-west Finland to secrete 0.3% of their biomass as fucoidan per day. Dissolved fucoidan concentrations in seawater adjacent to algae reached up to 0.48 mg L-1. Fucoidan accumulated during incubations of F. vesiculosus, significantly more in light than in darkness. Maximum estimation by acid hydrolysis indicated fucoidan secretion at a rate of 28 to 40 mg C kg-1 h-1, accounting for 44 to 50% of all exuded dissolved organic carbon. Composed only of carbon, oxygen, hydrogen, and sulfur, fucoidan secretion does not consume nutrients enabling carbon sequestration independent of algal growth. Extrapolated over a year, the algae sequester more carbon into secreted fucoidan than their biomass. The global utility of fucoidan secretion is an alternative pathway for carbon dioxide removal by brown algae without the need to harvest or bury algal biomass.
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Affiliation(s)
- Hagen Buck-Wiese
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
- University of Bremen, Center for Marine Environmental Sciences, MARUM, 28359Bremen, Germany
| | - Mona A. Andskog
- Centre for Coastal Biogeochemistry, Southern Cross University, 2480Lismore, Australia
| | - Nguyen P. Nguyen
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
- University of Bremen, Center for Marine Environmental Sciences, MARUM, 28359Bremen, Germany
| | - Margot Bligh
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
- University of Bremen, Center for Marine Environmental Sciences, MARUM, 28359Bremen, Germany
| | - Eero Asmala
- Geological Survey of Finland, Environmental Solutions, 02151Espoo, Finland
| | - Silvia Vidal-Melgosa
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
- University of Bremen, Center for Marine Environmental Sciences, MARUM, 28359Bremen, Germany
| | - Manuel Liebeke
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
| | - Camilla Gustafsson
- University of Helsinki, Tvärminne Zoological Station, 10900Hanko, Finland
| | - Jan-Hendrik Hehemann
- Max Planck Institute for Marine Microbiology, 28359Bremen, Germany
- University of Bremen, Center for Marine Environmental Sciences, MARUM, 28359Bremen, Germany
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21
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Sternberg‐Rodríguez P, Ezcurra P, Costa MT, Aburto‐Oropeza O, Ezcurra E. Precision of mangrove sediment blue carbon estimates and the role of coring and data analysis methods. Ecol Evol 2022; 12:e9655. [PMID: 36582778 PMCID: PMC9790802 DOI: 10.1002/ece3.9655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/27/2022] Open
Abstract
Carbon accumulation in coastal wetlands is normally assessed by extracting a sediment core and estimating its carbon content and bulk density. Because carbon content and bulk density are functionally related, the latter can be estimated gravimetrically from a section of the core or, alternatively, from the carbon content in the sample using the mixing model equation from soil science. Using sediment samples from La Paz Bay, Mexico, we analyzed the effect that the choice of corer and the method used to estimate bulk density could have on the final estimates of carbon storage in the sediments. We validated the results using a larger dataset of tropical mangroves, and then by Monte Carlo simulation. The choice of corer did not have sizable influence on the final estimates of carbon density. The main factor in selecting a corer is the operational difficulties that each corer may have in different types of sediments. Because of the multiplication of errors in a product of two variables subject to random sampling error, when using gravimetric estimates of bulk density, the dispersion of the data points in the estimation of total carbon density rises rapidly as the amount of carbon in the sediment increases. In contrast, the estimation of total carbon density using only the carbon fraction as a predictor is very precise, especially in sediments rich in organic matter. This method, however, depends critically on the accurate estimation of the two parameters of the mixing model: the bulk density of pure peat and the bulk density of pure mineral sediment. The estimation of carbon densities in peaty sediments can be very imprecise when using gravimetric bulk densities. Estimating carbon density in peaty sediments using only the estimate of organic fraction can be much more precise, provided the model parameters are estimated with accuracy. These results open the door for simplified and precise estimates of carbon dynamics in mangroves and coastal wetlands.
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Affiliation(s)
| | | | - Matthew T. Costa
- Scripps Institution of OceanographyUniversity of CaliforniaSan DiegoCaliforniaUSA
| | | | - Exequiel Ezcurra
- Department of Botany & Plant SciencesUniversity of CaliforniaRiversideCaliforniaUSA
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22
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Zhang X, Zhang C, Liu Y, Zhang R, Li M. Non-negligible roles of archaea in coastal carbon biogeochemical cycling. Trends Microbiol 2022; 31:586-600. [PMID: 36567186 DOI: 10.1016/j.tim.2022.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 11/16/2022] [Accepted: 11/18/2022] [Indexed: 12/25/2022]
Abstract
Coastal zones are among the world's most productive ecosystems. They store vast amounts of organic carbon, as 'blue carbon' reservoirs, and impact global climate change. Archaeal communities are integral components of coastal microbiomes but their ecological roles are often overlooked. However, archaeal diversity, metabolism, evolution, and interactions, revealed by recent studies using rapidly developing cutting-edge technologies, place archaea as important players in coastal carbon biogeochemical cycling. We here summarize the latest advances in the understanding of archaeal carbon cycling processes in coastal ecosystems, specifically, archaeal involvement in CO2 fixation, organic biopolymer transformation, and methane metabolism. We also showcase the potential to use of archaeal communities to increase carbon sequestration and reduce methane production, with implications for mitigating climate change.
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Affiliation(s)
- Xinxu Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Cuijing Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Rui Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Meng Li
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China.
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23
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Bell LE, Kroeker KJ. Standing Crop, Turnover, and Production Dynamics of Macrocystis pyrifera and Understory Species Hedophyllum nigripes and Neoagarum fimbriatum in High Latitude Giant Kelp Forests. J Phycol 2022; 58:773-788. [PMID: 36302142 PMCID: PMC10100489 DOI: 10.1111/jpy.13291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Production rates reported for canopy-forming kelps have highlighted the potential contributions of these foundational macroalgal species to carbon cycling and sequestration on a globally relevant scale. Yet, the production dynamics of many kelp species remain poorly resolved. For example, productivity estimates for the widely distributed giant kelp Macrocystis pyrifera are based on a few studies from the center of this species' range. To address this geospatial bias, we surveyed giant kelp beds in their high latitude fringe habitat in southeast Alaska to quantify foliar standing crop, growth and loss rates, and productivity of M. pyrifera and co-occurring understory kelps Hedophyllum nigripes and Neoagarum fimbriatum. We found that giant kelp beds at the poleward edge of their range produce ~150 g C · m-2 · year-1 from a standing biomass that turns over an estimated 2.1 times per year, substantially lower rates than have been observed at lower latitudes. Although the productivity of high latitude M. pyrifera dwarfs production by associated understory kelps in both winter and summer seasons, phenological differences in growth and relative carbon and nitrogen content among the three kelp species suggests their complementary value as nutritional resources to consumers. This work represents the highest latitude consideration of M. pyrifera forest production to date, providing a valuable quantification of kelp carbon cycling in this highly seasonal environment.
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Affiliation(s)
- Lauren E. Bell
- Ecology and Evolutionary BiologyUniversity of California Santa Cruz130 McAllister WaySanta CruzCalifornia95060USA
| | - Kristy J. Kroeker
- Ecology and Evolutionary BiologyUniversity of California Santa Cruz130 McAllister WaySanta CruzCalifornia95060USA
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24
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Durfort A, Mariani G, Tulloch V, Savoca MS, Troussellier M, Mouillot D. Recovery of carbon benefits by overharvested baleen whale populations is threatened by climate change. Proc Biol Sci 2022; 289:20220375. [PMID: 36321488 PMCID: PMC9627705 DOI: 10.1098/rspb.2022.0375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 10/10/2022] [Indexed: 12/03/2022] Open
Abstract
Despite the importance of marine megafauna on ecosystem functioning, their contribution to the oceanic carbon cycle is still poorly known. Here, we explored the role of baleen whales in the biological carbon pump across the southern hemisphere based on the historical and forecasted abundance of five baleen whale species. We modelled whale-mediated carbon sequestration through the sinking of their carcasses after natural death. We provide the first temporal dynamics of this carbon pump from 1890 to 2100, considering both the effects of exploitation and climate change on whale populations. We reveal that at their pre-exploitation abundance, the five species of southern whales could sequester 4.0 × 105 tonnes of carbon per year (tC yr-1). This estimate dropped to 0.6 × 105 tC yr-1 by 1972 following commercial whaling. However, with the projected restoration of whale populations under a RCP8.5 climate scenario, the sequestration would reach 1.7 × 105 tC yr-1 by 2100, while without climate change, recovered whale populations could sequester nearly twice as much (3.2 × 105 tC yr-1) by 2100. This highlights the persistence of whaling damages on whale populations and associated services as well as the predicted harmful impacts of climate change on whale ecosystem services.
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Affiliation(s)
- Anaëlle Durfort
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Gaël Mariani
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Vivitskaia Tulloch
- Department of Forest and Conservation Science, University of British Columbia, Vancouver, BC, Canada
| | | | | | - David Mouillot
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- Institut Universitaire de France, 75231, Paris, France
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25
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Xia S, Song Z, Van Zwieten L, Guo L, Yu C, Wang W, Li Q, Hartley IP, Yang Y, Liu H, Wang Y, Ran X, Liu CQ, Wang H. Storage, patterns and influencing factors for soil organic carbon in coastal wetlands of China. Glob Chang Biol 2022; 28:6065-6085. [PMID: 35771205 DOI: 10.1111/gcb.16325] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Soil organic carbon (SOC) in coastal wetlands, also known as "blue C," is an essential component of the global C cycles. To gain a detailed insight into blue C storage and controlling factors, we studied 142 sites across ca. 5000 km of coastal wetlands, covering temperate, subtropical, and tropical climates in China. The wetlands represented six vegetation types (Phragmites australis, mixed of P. australis and Suaeda, single Suaeda, Spartina alterniflora, mangrove [Kandelia obovata and Avicennia marina], tidal flat) and three vegetation types invaded by S. alterniflora (P. australis, K. obovata, A. marina). Our results revealed large spatial heterogeneity in SOC density of the top 1-m ranging 40-200 Mg C ha-1 , with higher values in mid-latitude regions (25-30° N) compared with those in both low- (20°N) and high-latitude (38-40°N) regions. Vegetation type influenced SOC density, with P. australis and S. alterniflora having the largest SOC density, followed by mangrove, mixed P. australis and Suaeda, single Suaeda and tidal flat. SOC density increased by 6.25 Mg ha-1 following S. alterniflora invasion into P. australis community but decreased by 28.56 and 8.17 Mg ha-1 following invasion into K. obovata and A. marina communities. Based on field measurements and published literature, we calculated a total inventory of 57 × 106 Mg C in the top 1-m soil across China's coastal wetlands. Edaphic variables controlled SOC content, with soil chemical properties explaining the largest variance in SOC content. Climate did not control SOC content but had a strong interactive effect with edaphic variables. Plant biomass and quality traits were a minor contributor in regulating SOC content, highlighting the importance of quantity and quality of OC inputs and the balance between production and degradation within the coastal wetlands. These findings provide new insights into blue C stabilization mechanisms and sequestration capacity in coastal wetlands.
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Affiliation(s)
- Shaopan Xia
- Institute of Resource, Ecosystem and Environment of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- School of Earth System Science, Institute of Surface-Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Zhaoliang Song
- School of Earth System Science, Institute of Surface-Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin, China
| | - Lukas Van Zwieten
- Wollongbar Primary Industries Institute, NSW Department of Primary Industries, Wollongbar, NSW, Australia
| | - Laodong Guo
- School of Freshwater Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
| | - Changxun Yu
- Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Weiqi Wang
- Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Qiang Li
- School of Earth System Science, Institute of Surface-Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Iain P Hartley
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Hongyan Liu
- College of Urban and Environmental Sciences, Peking University, Peking, China
| | - Yidong Wang
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin, China
| | - Xiangbin Ran
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao, China
| | - Cong-Qiang Liu
- School of Earth System Science, Institute of Surface-Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin, China
| | - Hailong Wang
- School of Environment and Chemical Engineering, Foshan University, Foshan, Guangdong, China
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, Zhejiang, China
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26
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Sea MA, Hillman JR, Thrush SF. The influence of mussel restoration on coastal carbon cycling. Glob Chang Biol 2022; 28:5269-5282. [PMID: 35656817 PMCID: PMC9544040 DOI: 10.1111/gcb.16287] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/19/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Increasing responsiveness to anthropogenic climate change and the loss of global shellfish ecosystems has heightened interest in the carbon storage and sequestration potential of bivalve-dominated systems. While coastal ecosystems are dynamic zones of carbon transformation and change, current uncertainties and notable heterogeneity in the benthic environment make it difficult to ascertain the climate change mitigation capacity of ongoing coastal restoration projects aimed at revitalizing benthic bivalve populations. In this study we sought to distinguish between direct and indirect effects of subtidal green-lipped mussels (Perna canaliculus) on carbon cycling, and combined published literature with in-situ experiments from restored beds to create a carbon budget for New Zealand's shellfish restoration efforts. A direct summation of biogenic calcification, community respiration, and sediment processes suggests a moderate carbon efflux (+100.1 to 179.6 g C m-2 year-1 ) occurs as a result of recent restoration efforts, largely reflective of the heterotrophic nature of bivalves. However, an examination of indirect effects of restoration on benthic community metabolism and sediment dynamics suggests that beds achieve greater carbon fixation rates and support enhanced carbon burial compared to nearby sediments devoid of mussels. We discuss limitations to our first-order approximation and postulate how the significance of mussel restoration to carbon-related outcomes likely increases over longer timescales. Coastal restoration is often conducted to support the provisioning of many ecosystem services, and we propose here that shellfish restoration not be used as a single measure to offset carbon dioxide emissions, but rather used in tandem with other initiatives to recover a bundle of valued ecosystem services.
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Affiliation(s)
- Mallory A. Sea
- Institute of Marine Science, University of AucklandAucklandNew Zealand
| | - Jenny R. Hillman
- Institute of Marine Science, University of AucklandAucklandNew Zealand
| | - Simon F. Thrush
- Institute of Marine Science, University of AucklandAucklandNew Zealand
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27
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Lee J, Gambi MC, Kroeker KJ, Munari M, Peay K, Micheli F. Resilient consumers accelerate the plant decomposition in a naturally acidified seagrass ecosystem. Glob Chang Biol 2022; 28:4558-4576. [PMID: 35583009 DOI: 10.1111/gcb.16265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 03/15/2022] [Accepted: 03/22/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic stressors are predicted to alter biodiversity and ecosystem functioning worldwide. However, scaling up from species to ecosystem responses poses a challenge, as species and functional groups can exhibit different capacities to adapt, acclimate, and compensate under changing environments. We used a naturally acidified seagrass ecosystem (the endemic Mediterranean Posidonia oceanica) as a model system to examine how ocean acidification (OA) modifies the community structure and functioning of plant detritivores, which play vital roles in the coastal nutrient cycling and food web dynamics. In seagrass beds associated with volcanic CO2 vents (Ischia, Italy), we quantified the effects of OA on seagrass decomposition by deploying litterbags in three distinct pH zones (i.e., ambient, low, extreme low pH), which differed in the mean and variability of seawater pH. We replicated the study in two discrete vents for 117 days (litterbags sampled on day 5, 10, 28, 55, and 117). Acidification reduced seagrass detritivore richness and diversity through the loss of less abundant, pH-sensitive species but increased the abundance of the dominant detritivore (amphipod Gammarella fucicola). Such compensatory shifts in species abundance caused more than a threefold increase in the total detritivore abundance in lower pH zones. These community changes were associated with increased consumption (52%-112%) and decay of seagrass detritus (up to 67% faster decomposition rate for the slow-decaying, refractory detrital pool) under acidification. Seagrass detritus deployed in acidified zones showed increased N content and decreased C:N ratio, indicating that altered microbial activities under OA may have affected the decay process. The findings suggest that OA could restructure consumer assemblages and modify plant decomposition in blue carbon ecosystems, which may have important implications for carbon sequestration, nutrient recycling, and trophic transfer. Our study highlights the importance of within-community response variability and compensatory processes in modulating ecosystem functions under extreme global change scenarios.
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Affiliation(s)
- Juhyung Lee
- Hopkins Marine Station of Stanford University, Pacific Grove, California, USA
- Department of Biology, Stanford University, Stanford, California, USA
| | | | - Kristy J Kroeker
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California, USA
| | - Marco Munari
- Department of Integrative Marine Ecology, Ischia Marine Centre, Stazione Zoologica Anton Dohrn, Ischia, Naples, Italy
| | - Kabir Peay
- Department of Biology, Stanford University, Stanford, California, USA
| | - Fiorenza Micheli
- Hopkins Marine Station of Stanford University, Pacific Grove, California, USA
- Department of Biology, Stanford University, Stanford, California, USA
- Stanford Center for Ocean Solutions, Pacific Grove, California, USA
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28
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Sanders-DeMott R, Eagle MJ, Kroeger KD, Wang F, Brooks TW, O'Keefe Suttles JA, Nick SK, Mann AG, Tang J. Impoundment increases methane emissions in Phragmites-invaded coastal wetlands. Glob Chang Biol 2022; 28:4539-4557. [PMID: 35616054 DOI: 10.1111/gcb.16217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/31/2022] [Accepted: 04/12/2022] [Indexed: 06/15/2023]
Abstract
Saline tidal wetlands are important sites of carbon sequestration and produce negligible methane (CH4 ) emissions due to regular inundation with sulfate-rich seawater. Yet, widespread management of coastal hydrology has restricted tidal exchange in vast areas of coastal wetlands. These ecosystems often undergo impoundment and freshening, which in turn cause vegetation shifts like invasion by Phragmites, that affect ecosystem carbon balance. Understanding controls and scaling of carbon exchange in these understudied ecosystems is critical for informing climate consequences of blue carbon restoration and/or management interventions. Here, we (1) examine how carbon fluxes vary across a salinity gradient (4-25 psu) in impounded and natural, tidally unrestricted Phragmites wetlands using static chambers and (2) probe drivers of carbon fluxes within an impounded coastal wetland using eddy covariance at the Herring River in Wellfleet, MA, United States. Freshening across the salinity gradient led to a 50-fold increase in CH4 emissions, but effects on carbon dioxide (CO2 ) were less pronounced with uptake generally enhanced in the fresher, impounded sites. The impounded wetland experienced little variation in water-table depth or salinity during the growing season and was a strong CO2 sink of -352 g CO2 -C m-2 year-1 offset by CH4 emission of 11.4 g CH4 -C m-2 year-1 . Growing season CH4 flux was driven primarily by temperature. Methane flux exhibited a diurnal cycle with a night-time minimum that was not reflected in opaque chamber measurements. Therefore, we suggest accounting for the diurnal cycle of CH4 in Phragmites, for example by applying a scaling factor developed here of ~0.6 to mid-day chamber measurements. Taken together, these results suggest that although freshened, impounded wetlands can be strong carbon sinks, enhanced CH4 emission with freshening reduces net radiative balance. Restoration of tidal flow to impounded ecosystems could limit CH4 production and enhance their climate regulating benefits.
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Affiliation(s)
- Rebecca Sanders-DeMott
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | - Meagan J Eagle
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | - Kevin D Kroeger
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | - Faming Wang
- Marine Biological Laboratory, Woods Hole, Massachusetts, USA
- Xiaoliang Research Station for Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Thomas W Brooks
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | | | - Sydney K Nick
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | - Adrian G Mann
- U. S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts, USA
| | - Jianwu Tang
- Marine Biological Laboratory, Woods Hole, Massachusetts, USA
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Quigley KM, Hein M, Suggett DJ. Translating the 10 golden rules of reforestation for coral reef restoration. Conserv Biol 2022; 36:e13890. [PMID: 35075743 PMCID: PMC9543798 DOI: 10.1111/cobi.13890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 12/10/2021] [Accepted: 01/03/2022] [Indexed: 05/26/2023]
Abstract
Efforts are accelerating to protect and restore ecosystems globally. With trillions of dollars in ecosystem services at stake, no clear framework exists for developing or prioritizing approaches to restore coral reefs even as efforts and investment opportunities to do so grow worldwide. Restoration may buy time for climate change mitigation, but it lacks rigorous guidance to meet objectives of scalability and effectiveness. Lessons from restoration of terrestrial ecosystems can and should be rapidly adopted for coral reef restoration. We propose how the 10 golden rules of effective forest restoration can be translated to accelerate efforts to restore coral reefs based on established principles of resilience, management, and local stewardship. We summarize steps to undertake reef restoration as a management strategy in the context of the diverse ecosystem service values that coral reefs provide. Outlining a clear blueprint is timely as more stakeholders seek to undertake restoration as the UN Decade on Ecosystem Restoration begins.
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Affiliation(s)
- Kate M. Quigley
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
- Division of Research & InnovationJames Cook UniversityTownsvilleQueenslandAustralia
| | - Margaux Hein
- Division of Research & InnovationJames Cook UniversityTownsvilleQueenslandAustralia
- MER Research and ConsultingMonaco
| | - David J. Suggett
- Faculty of Science, Climate Change ClusterUniversity of Technology SydneyUltimoNew South WalesAustralia
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Bernardino AF, Mazzuco ACA, Souza FM, Santos TMT, Sanders CJ, Massone CG, Costa RF, Silva AEB, Ferreira TO, Nóbrega GN, Silva TSF, Kauffman JB. The novel mangrove environment and composition of the Amazon Delta. Curr Biol 2022; 32:3636-3640.e2. [PMID: 35863350 DOI: 10.1016/j.cub.2022.06.071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/25/2022]
Abstract
Both freshwater floodplain (várzeas and igapós) forests and brackish-saline mangroves are abundant and well-described ecosystems in Brazil.1 However, an interesting and unique wetland forest exists in the Amazon Delta where extensive mangroves occur in essentially freshwater tidal environments. Unlike the floodplain forests found upriver, the hydrology of these ecosystems is driven largely by large macro-tides of 4-8 m coupled with the significant freshwater discharge from the Amazon River. We explored these mangroves on the Amazon Delta (00°52' N to 01°41' N) and found surface water salinity to be consistently <5; soil pore water salinity in these mangrove forests ranged from 0 nearest the Amazon mouth to only 5-11 at the coastal margins to the north (01°41' N, 49°55' W). We also recorded a unique mix of mangrove-obligate (Avicennia sp., Rhizophora mangle) and facultative-wetland species (Mauritia flexuosa, Pterocarpus sp.) dominating these forests. This unique mix of plant species and soil porewater chemistry exists even along the coastal strands and active coastlines of the Atlantic Ocean. Part of these unique mangroves have escaped current global satellite mapping efforts, and we estimate that they may add over 180 km2 (20% increase in mangrove area) within the Amazon Delta. Despite having a unique structure and function, these freshwater-brackish ecosystems likely provide similar ecosystem services to most mangroves worldwide, such as sequestering large quantities of organic carbon, protection of shoreline ecosystems from erosion, and habitats to many terrestrial and aquatic species (monkeys, birds, crabs, and fish).
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Affiliation(s)
- Angelo F Bernardino
- Departamento de Oceanografia, Universidade Federal do Espirito Santo, Av. Fernando Ferrari, 514, Vitória, Espirito Santo 29075910, Brazil.
| | - Ana Carolina A Mazzuco
- Departamento de Oceanografia, Universidade Federal do Espirito Santo, Av. Fernando Ferrari, 514, Vitória, Espirito Santo 29075910, Brazil
| | - Fernanda M Souza
- Departamento de Oceanografia, Universidade Federal do Espirito Santo, Av. Fernando Ferrari, 514, Vitória, Espirito Santo 29075910, Brazil
| | - Thuareag M T Santos
- Departamento de Oceanografia, Universidade Federal do Espirito Santo, Av. Fernando Ferrari, 514, Vitória, Espirito Santo 29075910, Brazil
| | - Christian J Sanders
- National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW 2450, Australia
| | - Carlos G Massone
- Departamento de Química, PUC-Rio, Rua Marquês de São Vicente, 225, Gávea, Rio de Janeiro 22451-900, Brazil
| | - Rodolfo F Costa
- Departamento de Ciência do Solo, Universidade de São Paulo, Av. Pádua Dias, 11, Piracicaba 13418-900, Brazil
| | - Antônio Elves B Silva
- Departamento de Ciência do Solo, Universidade de São Paulo, Av. Pádua Dias, 11, Piracicaba 13418-900, Brazil
| | - Tiago O Ferreira
- Departamento de Ciência do Solo, Universidade de São Paulo, Av. Pádua Dias, 11, Piracicaba 13418-900, Brazil
| | - Gabriel N Nóbrega
- Departamento de Geoquímica, Universidade Federal Fluminense, Outeiro São João Batista, S/N, Centro, Niterói 24020-141, Brazil
| | - Thiago S F Silva
- Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, UK
| | - J Boone Kauffman
- Department of Fisheries, Wildlife, and Conservation Sciences, Oregon State University, 104 Nash Hall, Corvallis, OR 97331, USA
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Roth F, Sun X, Geibel MC, Prytherch J, Brüchert V, Bonaglia S, Broman E, Nascimento F, Norkko A, Humborg C. High spatiotemporal variability of methane concentrations challenges estimates of emissions across vegetated coastal ecosystems. Glob Chang Biol 2022; 28:4308-4322. [PMID: 35340089 PMCID: PMC9540812 DOI: 10.1111/gcb.16177] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Coastal methane (CH4 ) emissions dominate the global ocean CH4 budget and can offset the "blue carbon" storage capacity of vegetated coastal ecosystems. However, current estimates lack systematic, high-resolution, and long-term data from these intrinsically heterogeneous environments, making coastal budgets sensitive to statistical assumptions and uncertainties. Using continuous CH4 concentrations, δ13 C-CH4 values, and CH4 sea-air fluxes across four seasons in three globally pervasive coastal habitats, we show that the CH4 distribution is spatially patchy over meter-scales and highly variable in time. Areas with mixed vegetation, macroalgae, and their surrounding sediments exhibited a spatiotemporal variability of surface water CH4 concentrations ranging two orders of magnitude (i.e., 6-460 nM CH4 ) with habitat-specific seasonal and diurnal patterns. We observed (1) δ13 C-CH4 signatures that revealed habitat-specific CH4 production and consumption pathways, (2) daily peak concentration events that could change >100% within hours across all habitats, and (3) a high thermal sensitivity of the CH4 distribution signified by apparent activation energies of ~1 eV that drove seasonal changes. Bootstrapping simulations show that scaling the CH4 distribution from few samples involves large errors, and that ~50 concentration samples per day are needed to resolve the scale and drivers of the natural variability and improve the certainty of flux calculations by up to 70%. Finally, we identify northern temperate coastal habitats with mixed vegetation and macroalgae as understudied but seasonally relevant atmospheric CH4 sources (i.e., releasing ≥ 100 μmol CH4 m-2 day-1 in summer). Due to the large spatial and temporal heterogeneity of coastal environments, high-resolution measurements will improve the reliability of CH4 estimates and confine the habitat-specific contribution to regional and global CH4 budgets.
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Affiliation(s)
- Florian Roth
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Tvärminne Zoological StationUniversity of HelsinkiHankoFinland
| | - Xiaole Sun
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Center of Deep Sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdaoChina
| | | | - John Prytherch
- Department of MeteorologyStockholm UniversityStockholmSweden
| | - Volker Brüchert
- Department of Geological SciencesStockholm UniversityStockholmSweden
- Bolin Centre for Climate ResearchStockholm UniversityStockholmSweden
| | - Stefano Bonaglia
- Department of Marine SciencesUniversity of GothenburgGothenburgSweden
| | - Elias Broman
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Department of EcologyEnvironment and Plant SciencesStockholm UniversityStockholmSweden
| | - Francisco Nascimento
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Department of EcologyEnvironment and Plant SciencesStockholm UniversityStockholmSweden
| | - Alf Norkko
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Tvärminne Zoological StationUniversity of HelsinkiHankoFinland
| | - Christoph Humborg
- Baltic Sea CentreStockholm UniversityStockholmSweden
- Tvärminne Zoological StationUniversity of HelsinkiHankoFinland
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Jankowska E, Pelc R, Alvarez J, Mehra M, Frischmann CJ. Climate benefits from establishing marine protected areas targeted at blue carbon solutions. Proc Natl Acad Sci U S A 2022; 119:e2121705119. [PMID: 35653565 DOI: 10.1073/pnas.2121705119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SignificanceMarine conservation and the establishment of marine protected areas (MPAs) have gained attention as ways to protect and restore ecosystems and rebuild fish populations. They may also play an important role in sequestering carbon and reducing emissions from sources such as habitat degradation. Implementing six strategies for enhancing blue carbon sinks, including establishing MPAs to protect and restore coastal wetlands, macroalgae forests, and seafloor sediments and expand seaweed farming can not only remove significant amounts of carbon and avoid emissions but also bring many more environmental and human-related benefits.
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Dolliver J, O’Connor N. Whole System Analysis Is Required To Determine The Fate Of Macroalgal Carbon: A Systematic Review. J Phycol 2022; 58:364-376. [PMID: 35397178 PMCID: PMC9325415 DOI: 10.1111/jpy.13251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
The role of marine primary producers in capturing atmospheric CO2 has received increased attention in the global mission to mitigate climate change. Yet, our understanding of carbon sequestration performed by macroalgae has been limited to a relatively small number of studies that have estimated the ultimate fate of macroalgal-derived carbon. This systematic review was conducted to provide a timely synthesis of the methods used to determine the fate of macroalgal carbon in this rapidly expanding research area. It also aimed to provide suggestions for more effective future research. We found that the most common methods to estimate the fate of macroalgal carbon can be categorized into groups based on those that quantify: (i) export of macroalgal carbon to other environments-known as horizontal transport; (ii) sequestration of macroalgal carbon into deep-sea sediments-known as vertical transport; (iii) burial of macroalgal carbon directly beneath a benthic community; (iv) the loss of macroalgal carbon as particulate carbon or dissolved carbon to the water column; (v) the loss of macroalgal carbon to primary consumers; and finally (vi) those studies that combined multiple methods in one location. Based on this review, several recommendations for future research were formulated, which require the combination of multiple methods in a whole system analysis approach.
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Affiliation(s)
- Jessie Dolliver
- Department of ZoologyTrinity College DublinDublinD02 F6N2Ireland
- Department of Plant SciencesUniversity of OxfordOxfordOX1 3RBUK
| | - Nessa O’Connor
- Department of ZoologyTrinity College DublinDublinD02 F6N2Ireland
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Liu C, Liu G, Casazza M, Yan N, Xu L, Hao Y, Franzese PP, Yang Z. Current Status and Potential Assessment of China's Ocean Carbon Sinks. Environ Sci Technol 2022; 56:6584-6595. [PMID: 35507754 DOI: 10.1021/acs.est.1c08106] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The role of ocean carbon sinks in global climate change mitigation and carbon neutrality is still affected by lack of research. Aiming at overcoming the present limitations, a comprehensive and holistic framework and accounting method of ocean carbon sink evaluation are proposed in this study, which consider both carbon sink types and their characteristic carbon storage cycle timescales. The results show that (1) China's total ocean carbon sink is 69.83-106.46 Tg C/year, among which the mariculture, coastal wetlands, and offshore carbon sinks are 2.27-4.06, 2.86-5.85, and 64.70-96.55 Tg C/year, respectively; (2) ocean-based solutions such as coastal protection and restoration, mariculture development, ocean alkalization, ocean fertilization, and marine bioenergy with carbon capture and storage have substantial mitigation potential, but further investigation is required before large-scale deployment; (3) although China's ocean carbon sinks only counterbalanced 3.27-4.99% of its fossil fuel emissions, their tremendous enhancing potential and specific advantages cannot be ignored, and enhancing measures must be taken according to regional characteristics; (4) some uncertainties and limitations still exist, and problems such as double counting, carbon sink offset, and so forth need to be further considered. In a word, this study provides a basis for the development of ocean-based solutions on closing climate mitigation gaps.
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Affiliation(s)
- Chang Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Gengyuan Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
- Beijing Engineering Research Center for Watershed Environmental Restoration & Integrated Ecological Regulation, Beijing 100875, China
| | - Marco Casazza
- Department of Medicine, Surgery and Odontology "Scuola Medica Salernitana", University of Salerno, Baronissi, Salerno 84081, Italy
| | - Ningyu Yan
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Linyu Xu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
- Beijing Engineering Research Center for Watershed Environmental Restoration & Integrated Ecological Regulation, Beijing 100875, China
| | - Yan Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
- Beijing Engineering Research Center for Watershed Environmental Restoration & Integrated Ecological Regulation, Beijing 100875, China
| | - Pier Paolo Franzese
- Laboratory of Ecodynamics and Sustainable Development, Department of Science and Technology, Parthenope University of Naples, Centro Direzionale─Isola C4, Napoli 80143, Italy
| | - Zhifeng Yang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
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35
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Epstein G, Middelburg JJ, Hawkins JP, Norris CR, Roberts CM. The impact of mobile demersal fishing on carbon storage in seabed sediments. Glob Chang Biol 2022; 28:2875-2894. [PMID: 35174577 PMCID: PMC9307015 DOI: 10.1111/gcb.16105] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 12/17/2021] [Indexed: 05/26/2023]
Abstract
Subtidal marine sediments are one of the planet's primary carbon stores and strongly influence the oceanic sink for atmospheric CO2 . By far the most widespread human activity occurring on the seabed is bottom trawling/dredging for fish and shellfish. A global first-order estimate suggested mobile demersal fishing activities may cause 0.16-0.4 Gt of organic carbon (OC) to be remineralized annually from seabed sediment carbon stores (Sala et al., 2021). There are, however, many uncertainties in this calculation. Here, we discuss the potential drivers of change in seabed sediment OC stores due to mobile demersal fishing activities and conduct a literature review, synthesizing studies where this interaction has been directly investigated. Under certain environmental settings, we hypothesize that mobile demersal fishing would reduce OC in seabed stores due to lower production of flora and fauna, the loss of fine flocculent material, increased sediment resuspension, mixing and transport and increased oxygen exposure. Reductions would be offset to varying extents by reduced faunal bioturbation and community respiration, increased off-shelf transport and increases in primary production from the resuspension of nutrients. Studies which directly investigated the impact of demersal fishing on OC stocks had mixed results. A finding of no significant effect was reported in 61% of 49 investigations; 29% reported lower OC due to fishing activities, with 10% reporting higher OC. In relation to remineralization rates within the seabed, four investigations reported that demersal fishing activities decreased remineralization, with three reporting higher remineralization rates. Patterns in the environmental and experimental characteristics between different outcomes were largely indistinct. More evidence is urgently needed to accurately quantify the impact of anthropogenic physical disturbance on seabed carbon in different environmental settings and to incorporate full evidence-based carbon considerations into global seabed management.
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Affiliation(s)
- Graham Epstein
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
| | | | - Julie P. Hawkins
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
| | - Catrin R. Norris
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
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Arifanti VB, Kauffman JB, Subarno, Ilman M, Tosiani A, Novita N. Contributions of mangrove conservation and restoration to climate change mitigation in Indonesia. Glob Chang Biol 2022; 28:4523-4538. [PMID: 35470521 PMCID: PMC9325550 DOI: 10.1111/gcb.16216] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/04/2022] [Accepted: 03/10/2022] [Indexed: 05/28/2023]
Abstract
Mangrove forests are important carbon sinks and this is especially true for Indonesia where about 24% of the world's mangroves exist. Unfortunately, vast expanses of these mangroves have been deforested, degraded or converted to other uses resulting in significant greenhouse gas emissions. The objective of this study was to quantify the climate change mitigation potential of mangrove conservation and restoration in Indonesia. We calculated the emission factors from the dominant land uses in mangroves, determined mangrove deforestation rates and quantified the total emissions and the potential emission reductions that could be achieved from mangrove conservation and restoration. Based upon our analysis of the carbon stocks and emissions from land use in mangroves we found: (1) Indonesia's mangrove ecosystem carbon stocks are amongst the highest of any tropical forest type; (2) mangrove deforestation results in greenhouse gas emissions that far exceed that of upland tropical deforestation; (3) in the last decade the rates of deforestation in Indonesian mangroves have remained high; and (4) conservation and restoration of mangroves promise to sequester significant quantities of carbon. While mangroves comprise only ≈2.6% of Indonesia's total forest area, their degradation and deforestation accounted for ≈10% of total greenhouse gas emissions arising from the forestry sector. The large source of greenhouse gas emissions from a relatively small proportion of the forest area underscores the value for inclusion of mangroves as a natural climate solution (NCS). Mangrove conservation is far more effective than mangrove restoration in carbon emissions reductions and an efficient pathway to achieve Indonesia's nationally determined contribution (NDC) targets. The potential emission reduction from halting deforestation of primary and secondary mangroves coupled with restoration activities could result in an emission reduction equivalent to 8% of Indonesia's 2030 NDC emission reduction targets from the forestry sector.
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Affiliation(s)
- Virni Budi Arifanti
- Forest Research and Development Agency (FORDA), Ministry of Environment and Forestry, Republic of Indonesia, Jl Gunung Batu No. 5, Bogor, Indonesia
- National Research and Innovation Agency (BRIN), Republic of Indonesia, B. J. Habibie Building, Jl. M. H. Thamrin No. 8, Jakarta, Indonesia
| | - J Boone Kauffman
- Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Corvallis, OR 97331, USA and Illahee Sciences International, Corvallis, OR, USA
| | - Subarno
- Yayasan Konservasi Alam Nusantara, Graha Iskandarsyah Floor 3. Jl. Iskandarsyah Raya No.66 C. Kebayoran Baru, South Jakarta, Indonesia
| | - Muhammad Ilman
- Yayasan Konservasi Alam Nusantara, Graha Iskandarsyah Floor 3. Jl. Iskandarsyah Raya No.66 C. Kebayoran Baru, South Jakarta, Indonesia
| | - Anna Tosiani
- Directorate of Forest Resource Monitoring and Inventory, Ministry of Environment and Forestry, Manggala Wanabakti Building, 7th Floor, Jl. Gatot Subroto, Jakarta, Indonesia
| | - Nisa Novita
- Yayasan Konservasi Alam Nusantara, Graha Iskandarsyah Floor 3. Jl. Iskandarsyah Raya No.66 C. Kebayoran Baru, South Jakarta, Indonesia
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Schorn S, Ahmerkamp S, Bullock E, Weber M, Lott C, Liebeke M, Lavik G, Kuypers MMM, Graf JS, Milucka J. Diverse methylotrophic methanogenic archaea cause high methane emissions from seagrass meadows. Proc Natl Acad Sci U S A 2022; 119:e2106628119. [PMID: 35165204 DOI: 10.1073/pnas.2106628119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2021] [Indexed: 11/18/2022] Open
Abstract
Marine coastlines colonized by seagrasses are a net source of methane to the atmosphere. However, methane emissions from these environments are still poorly constrained, and the underlying processes and responsible microorganisms remain largely unknown. Here, we investigated methane turnover in seagrass meadows of Posidonia oceanica in the Mediterranean Sea. The underlying sediments exhibited median net fluxes of methane into the water column of ca. 106 µmol CH4 ⋅ m-2 ⋅ d-1 Our data show that this methane production was sustained by methylated compounds produced by the plant, rather than by fermentation of buried organic carbon. Interestingly, methane production was maintained long after the living plant died off, likely due to the persistence of methylated compounds, such as choline, betaines, and dimethylsulfoniopropionate, in detached plant leaves and rhizomes. We recovered multiple mcrA gene sequences, encoding for methyl-coenzyme M reductase (Mcr), the key methanogenic enzyme, from the seagrass sediments. Most retrieved mcrA gene sequences were affiliated with a clade of divergent Mcr and belonged to the uncultured Candidatus Helarchaeota of the Asgard superphylum, suggesting a possible involvement of these divergent Mcr in methane metabolism. Taken together, our findings identify the mechanisms controlling methane emissions from these important blue carbon ecosystems.
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Berg P, Huettel M, Glud RN, Reimers CE, Attard KM. Aquatic Eddy Covariance: The Method and Its Contributions to Defining Oxygen and Carbon Fluxes in Marine Environments. Ann Rev Mar Sci 2022; 14:431-455. [PMID: 34587456 DOI: 10.1146/annurev-marine-042121-012329] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Aquatic eddy covariance (AEC) is increasingly being used to study benthic oxygen (O2) flux dynamics, organic carbon cycling, and ecosystem health in marine and freshwater environments. Because it is a noninvasive technique, has a high temporal resolution (∼15 min), and integrates over a large area of the seafloor (typically 10-100 m2), it has provided new insights on the functioning of aquatic ecosystems under naturally varying in situ conditions and has given us more accurate assessments of their metabolism. In this review, we summarize biogeochemical, ecological, and biological insightsgained from AEC studies of marine ecosystems. A general finding for all substrates is that benthic O2 exchange is far more dynamic than earlier recognized, and thus accurate mean values can only be obtained from measurements that integrate over all timescales that affect the local O2 exchange. Finally, we highlight new developments of the technique, including measurements of air-water gas exchange and long-term deployments.
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Affiliation(s)
- Peter Berg
- Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia 22908, USA;
| | - Markus Huettel
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, Florida 32306, USA;
| | - Ronnie N Glud
- Danish Center for Hadal Research (HADAL), Nordic Center for Earth Evolution (NordCEE), Danish Institute for Advanced Study (DIAS), and Department of Biology, University of Southern Denmark, DK-5230 Odense M, Denmark; ,
- Department of Ocean and Environmental Sciences, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
| | - Clare E Reimers
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA;
| | - Karl M Attard
- Danish Center for Hadal Research (HADAL), Nordic Center for Earth Evolution (NordCEE), Danish Institute for Advanced Study (DIAS), and Department of Biology, University of Southern Denmark, DK-5230 Odense M, Denmark; ,
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Barnes DKA, Bell JB, Bridges AE, Ireland L, Howell KL, Martin SM, Sands CJ, Mora Soto A, Souster T, Flint G, Morley SA. Climate Mitigation through Biological Conservation: Extensive and Valuable Blue Carbon Natural Capital in Tristan da Cunha's Giant Marine Protected Zone. Biology (Basel) 2021; 10:1339. [PMID: 34943254 DOI: 10.3390/biology10121339] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary Solving biodiversity loss and climate change are part of the same problem; intact natural habitats can provide powerful and efficient climate mitigation if protected. Beyond the land (forests), there is little appreciation of just how important ocean nature is to climate mitigation. Carbon captured, stored and the rate at which it is buried (sequestration) by marine organisms is called blue carbon. We measured how much blue carbon occurs around the remote islands and seamounts of the Tristan da Cunha archipelago Marine Protected Zone (MPZ). We estimated that there are 300 tonnes of carbon (tC) captured in seaweed biomass each year, a proportion of which will sink and become a part of the long-term sediment carbon store. In deeper water we found a standing stock of ~2.3 million tC in the shallowest 1000 m depths, of which equivalent to 0.8 million t of carbon dioxide has the potential to be sequestered. At current carbon prices, and were it to attract blue carbon credits, £24 million worth of blue carbon can potentially be sequestered from the standing stock of this small United Kingdom Overseas Territory. This standing stock is protected and growth could, therefore, generate an additional £3.5 million worth of sequestered carbon a year, making it an unrecognized major component of the local economy. The economic return on this example MPZ probably ranks highly amongst climate mitigation schemes. The message is that placing meaningful protection to carbon-rich natural habitats can massively help society fight climate change and biodiversity loss. Nations who provide this protection should be fairly compensated, particularly where it comes at the detriment of other economic uses of marine habitats. Abstract Carbon-rich habitats can provide powerful climate mitigation if meaningful protection is put in place. We attempted to quantify this around the Tristan da Cunha archipelago Marine Protected Area. Its shallows (<1000 m depth) are varied and productive. The 5.4 km2 of kelp stores ~60 tonnes of carbon (tC) and may export ~240 tC into surrounding depths. In deep-waters we analysed seabed data collected from three research cruises, including seabed mapping, camera imagery, seabed oceanography and benthic samples from mini-Agassiz trawl. Rich biological assemblages on seamounts significantly differed to the islands and carbon storage had complex drivers. We estimate ~2.3 million tC are stored in benthic biodiversity of waters <1000 m, which includes >0.22 million tC that can be sequestered (the proportion of the carbon captured that is expected to become buried in sediment or locked away in skeletal tissue for at least 100 years). Much of this carbon is captured by cold-water coral reefs as a mixture of inorganic (largely calcium carbonate) and organic compounds. As part of its 2020 Marine Protection Strategy, these deep-water reef systems are now protected by a full bottom-trawling ban throughout Tristan da Cunha and representative no take areas on its seamounts. This small United Kingdom Overseas Territory’s reef systems represent approximately 0.8 Mt CO2 equivalent sequestered carbon; valued at >£24 Million GBP (at the UN shadow price of carbon). Annual productivity of this protected standing stock generates an estimated £3 million worth of sequestered carbon a year, making it an unrecognized and potentially major component of the economy of small island nations like Tristan da Cunha. Conservation of near intact habitats are expected to provide strong climate and biodiversity returns, which are exemplified by this MPA.
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Cormier N. Getting to the root of the problem: improving measurements of mangrove belowground production and carbon sequestration. New Phytol 2021; 232:1525-1527. [PMID: 34590716 DOI: 10.1111/nph.17723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Nicole Cormier
- Department of Earth and Environmental Sciences, Macquarie University, Sydney, NSW, 2109, Australia
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Queirós AM, Talbot E, Beaumont NJ, Somerfield PJ, Kay S, Pascoe C, Dedman S, Fernandes JA, Jueterbock A, Miller PI, Sailley SF, Sará G, Carr LM, Austen MC, Widdicombe S, Rilov G, Levin LA, Hull SC, Walmsley SF, Nic Aonghusa C. Bright spots as climate-smart marine spatial planning tools for conservation and blue growth. Glob Chang Biol 2021; 27:5514-5531. [PMID: 34486773 PMCID: PMC9291121 DOI: 10.1111/gcb.15827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/09/2021] [Accepted: 08/02/2021] [Indexed: 05/04/2023]
Abstract
Marine spatial planning that addresses ocean climate-driven change ('climate-smart MSP') is a global aspiration to support economic growth, food security and ecosystem sustainability. Ocean climate change ('CC') modelling may become a key decision-support tool for MSP, but traditional modelling analysis and communication challenges prevent their broad uptake. We employed MSP-specific ocean climate modelling analyses to inform a real-life MSP process; addressing how nature conservation and fisheries could be adapted to CC. We found that the currently planned distribution of these activities may become unsustainable during the policy's implementation due to CC, leading to a shortfall in its sustainability and blue growth targets. Significant, climate-driven ecosystem-level shifts in ocean components underpinning designated sites and fishing activity were estimated, reflecting different magnitudes of shifts in benthic versus pelagic, and inshore versus offshore habitats. Supporting adaptation, we then identified: CC refugia (areas where the ecosystem remains within the boundaries of its present state); CC hotspots (where climate drives the ecosystem towards a new state, inconsistent with each sectors' present use distribution); and for the first time, identified bright spots (areas where oceanographic processes drive range expansion opportunities that may support sustainable growth in the medium term). We thus create the means to: identify where sector-relevant ecosystem change is attributable to CC; incorporate resilient delivery of conservation and sustainable ecosystem management aims into MSP; and to harness opportunities for blue growth where they exist. Capturing CC bright spots alongside refugia within protected areas may present important opportunities to meet sustainability targets while helping support the fishing sector in a changing climate. By capitalizing on the natural distribution of climate resilience within ocean ecosystems, such climate-adaptive spatial management strategies could be seen as nature-based solutions to limit the impact of CC on ocean ecosystems and dependent blue economy sectors, paving the way for climate-smart MSP.
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Affiliation(s)
| | | | | | | | - Susan Kay
- Plymouth Marine LaboratoryPlymouthUK
| | | | - Simon Dedman
- Hopkins Marine StationStanford UniversityStanfordCaliforniaUSA
| | - Jose A. Fernandes
- AZTI‐Tecnalia, Marine ResearchBasque Research and Technology Alliance (BRTA)BizkaiaSpain
| | | | | | | | - Gianluca Sará
- Department of Earth and Marine ScienceLaboratory of EcologyUniversity of PalermoPalermoItaly
| | | | | | | | - Gil Rilov
- National Institute of OceanographyIsrael Oceanographic and Limnological Research InstituteHaifaIsrael
| | - Lisa A. Levin
- Scripps Institution of OceanographyUniversity of CaliforniaSan DiegoCaliforniaUSA
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Arnaud M, Morris PJ, Baird AJ, Dang H, Nguyen TT. Fine root production in a chronosequence of mature reforested mangroves. New Phytol 2021; 232:1591-1602. [PMID: 34018616 DOI: 10.1111/nph.17480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Mangroves are among the world's most carbon-dense ecosystems, but have suffered extensive deforestation, prompting reforestation projects. The effects of mangrove reforestation on belowground carbon dynamics are poorly understood. In particular, we do not know how fine root production develops following mangrove reforestation, despite fine root production being a major carbon sink and an important control of mangrove soil accretion. Using minirhizotrons, we investigated fine root production and its depth variation along a chronosequence of mature Vietnamese mangroves. Our results showed that fine root production decreases strongly with stand age in the uppermost 32 cm of our soil profiles. In younger mangrove stands, fine root production declines with depth, possibly due to a vertical gradient in soil nutrient availability; while root production in the oldest stand is low at all depths and exhibits no clear vertical pattern. A major fraction of fine root production occurs deeper than 30 cm, depths that are commonly omitted from calculations of mangrove carbon budgets. Younger mangroves may accrue shallow soil organic matter faster than older mangroves. Therefore, root productivity and forest stand age should be accounted for when forecasting mangrove carbon budgets and resistance to sea-level rise.
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Affiliation(s)
- Marie Arnaud
- Laboratoire Environnement et Ressources des Pertuis Charentais (LER-PC), IFREMER, La Tremblade, BP133, France
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Paul J Morris
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
| | - Andy J Baird
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
| | - Huyen Dang
- Faculty of Geology and Petroleum Engineering, Ho Chí Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet St., Dist. 10, Ho Chí Minh, Vietnam
| | - Tai Tue Nguyen
- VNU-University of Science, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam
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Tavares TCL, Bezerra WM, Normando LRO, Rosado AS, Melo VMM. Brazilian Semi-Arid Mangroves-Associated Microbiome as Pools of Richness and Complexity in a Changing World. Front Microbiol 2021; 12:715991. [PMID: 34512595 PMCID: PMC8427804 DOI: 10.3389/fmicb.2021.715991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 08/06/2021] [Indexed: 01/04/2023] Open
Abstract
Mangrove microbiomes play an essential role in the fate of mangroves in our changing planet, but the factors regulating the biogeographical distribution of mangrove microbial communities remain essentially vague. This paper contributes to our understanding of mangrove microbiomes distributed along three biogeographical provinces and ecoregions, covering the exuberant mangroves of Amazonia ecoregion (North Brazil Shelf) as well as mangroves located in the southern limit of distribution (Southeastern ecoregion, Warm Temperate Southwestern Atlantic) and mangroves localized on the drier semi-arid coast (Northeastern ecoregion, Tropical Southwestern Atlantic), two important ecotones where poleward and landward shifts, respectively, are expected to occur related to climate change. This study compared the microbiomes associated with the conspicuous red mangrove (Rhizophora mangle) root soils encompassing soil properties, latitudinal factors, and amplicon sequence variants of 105 samples. We demonstrated that, although the northern and southern sites are over 4,000 km apart, and despite R. mangle genetic divergences between north and south populations, their microbiomes resemble each other more than the northern and northeastern neighbors. In addition, the northeastern semi-arid microbiomes were more diverse and displayed a higher level of complexity than the northern and southern ones. This finding may reflect the endurance of the northeast microbial communities tailored to deal with the stressful conditions of semi-aridity and may play a role in the resistance and growing landward expansion observed in such mangroves. Minimum temperature, precipitation, organic carbon, and potential evapotranspiration were the main microbiota variation drivers and should be considered in mangrove conservation and recovery strategies in the Anthropocene. In the face of changes in climate, land cover, biodiversity, and chemical composition, the richness and complexity harbored by semi-arid mangrove microbiomes may hold the key to mangrove adaptability in our changing planet.
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Affiliation(s)
| | - Walderly Melgaço Bezerra
- Laboratory of Microbial Ecology and Biotechnology, Department of Biology, Federal University of Ceará (UFC), Fortaleza, Brazil
| | | | - Alexandre Soares Rosado
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Vânia Maria Maciel Melo
- Laboratory of Microbial Ecology and Biotechnology, Department of Biology, Federal University of Ceará (UFC), Fortaleza, Brazil
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Gajdzik L, DeCarlo TM, Aylagas E, Coker DJ, Green AL, Majoris JE, Saderne VF, Carvalho S, Berumen ML. A portfolio of climate-tailored approaches to advance the design of marine protected areas in the Red Sea. Glob Chang Biol 2021; 27:3956-3968. [PMID: 34021662 PMCID: PMC8453993 DOI: 10.1111/gcb.15719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 05/04/2023]
Abstract
Intensified coastal development is compromising the health and functioning of marine ecosystems. A key example of this is the Red Sea, a biodiversity hotspot subjected to increasing local human pressures. While some marine-protected areas (MPAs) were placed to alleviate these stressors, it is unclear whether these MPAs are managed or enforced, thus providing limited protection. Yet, most importantly, MPAs in the Red Sea were not designed using climate considerations, likely diminishing their effectiveness against global stressors. Here, we propose to tailor the design of MPAs in the Red Sea by integrating approaches to enhance climate change mitigation and adaptation. First, including coral bleaching susceptibility could produce a more resilient network of MPAs by safeguarding reefs from different thermal regions that vary in spatiotemporal bleaching responses, reducing the risk that all protected reefs will bleach simultaneously. Second, preserving the basin-wide genetic connectivity patterns that are assisted by mesoscale eddies could further ensure recovery of sensitive populations and maintain species potential to adapt to environmental changes. Finally, protecting mangrove forests in the northern and southern Red Sea that act as major carbon sinks could help offset greenhouse gas emissions. If implemented with multinational cooperation and concerted effort among stakeholders, our portfolio of climate-tailored approaches may help build a network of MPAs in the Red Sea that protects more effectively its coastal resources against escalating coastal development and climate instability. Beyond the Red Sea, we anticipate this study to serve as an example of how to improve the utility of tropical MPAs as climate-informed conservation tools.
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Affiliation(s)
- Laura Gajdzik
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Present address:
Division of Aquatic ResourcesDepartment of Land and Natural ResourcesState of HawaiʻiHonoluluHI96813USA
| | - Thomas M. DeCarlo
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Present address:
College of Natural and Computational SciencesHawaiʻi Pacific UniversityHonoluluHI96813USA
| | - Eva Aylagas
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Darren J. Coker
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Alison L. Green
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - John E. Majoris
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Vincent F. Saderne
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Susana Carvalho
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Michael L. Berumen
- Red Sea Research CenterKing Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
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Jimenez LCZ, Queiroz HM, Otero XL, Nóbrega GN, Ferreira TO. Soil Organic Matter Responses to Mangrove Restoration: A Replanting Experience in Northeast Brazil. Int J Environ Res Public Health 2021; 18:8981. [PMID: 34501570 DOI: 10.3390/ijerph18178981] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/14/2021] [Accepted: 08/24/2021] [Indexed: 12/31/2022]
Abstract
Mangroves are among the most relevant ecosystems in providing ecosystem services because of their capacity to act as sinks for atmospheric carbon. Thus, restoring mangroves is a strategic pathway for mitigating global climate change. Therefore, this study aimed to examine the organic matter dynamics in mangrove soils during restoration processes. Four mangrove soils under different developmental stages along the northeastern Brazilian coast were studied, including a degraded mangrove (DM); recovering mangroves after 3 years (3Y) and 7 years (7Y) of planting; and a mature mangrove (MM). The soil total organic carbon (CT) and soil carbon stocks (SCSs) were determined for each area. Additionally, a demineralization procedure was conducted to assess the most complex humidified and recalcitrant fractions of soil organic matter and the fraction participating in organomineral interactions. The particle size distribution was also analyzed. Our results revealed significant differences in the SCS and CT values between the DM, 3Y and 7Y, and the MM, for which there was a tendency to increase in carbon content with increasing vegetative development. However, based on the metrics used to evaluate organic matter interactions with inorganic fractions, such as low rates of carbon enrichment, C recovery, and low C content after hydrofluoric acid (HF) treatment being similar for the DM and the 3Y and 7Y—this indicated that high carbon losses were coinciding with mineral dissolution. These results indicate that the organic carbon dynamics in degraded and newly planted sites depend more on organomineral interactions, both to maintain their previous SCS and increase it, than mature mangroves. Conversely, the MM appeared to have most of the soil organic carbon, as the stabilized organic matter had a complex structure with a high molecular weight and contributed less in the organomineral interactions to the SCS. These results demonstrate the role of initial mangrove vegetation development in trapping fine mineral particles and favoring organomineral interactions. These findings will help elucidate organic accumulation in different replanted mangrove restoration scenarios.
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Cai W, Zhu Q, Chen M, Cai Y. Spatiotemporal Change and the Natural-Human Driving Processes of a Megacity's Coastal Blue Carbon Storage. Int J Environ Res Public Health 2021; 18:ijerph18168879. [PMID: 34444628 PMCID: PMC8395042 DOI: 10.3390/ijerph18168879] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022]
Abstract
Coastal blue carbon storage (CBCS) plays a key role in addressing global climate change and realizing regional carbon neutrality. Although blue carbon has been studied for some years, there is little understanding of the influence of a megacity’s complex natural and human-driven processes on CBCS. Taking the Shanghai coastal area as an example, this study investigated the spatiotemporal change in CBCS using the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model during 1990–2015, and analyzed the response of the CBCS to a megacity’s complex natural- and human-driven processes through a land use/land cover transition matrix and hierarchical clustering. The results were as follows: (1) Thirty-three driving processes were identified in the study area, including four natural processes (e.g., accretion, succession, erosion, etc.), two human processes (reclamation and restoration) and twenty-seven natural–human coupled processes; they were further combined into single and multiple processes with positive and negative influences on the CBCS into four types (Mono+, Mono−, Multiple+ and Multiple− driving processes). (2) Shanghai’s CBCS increased from 1659.44 × 104 Mg to 1789.78 ×104 Mg, though the amount of Shanghai’s coastal carbon sequestration showed a decreasing trend in three periods: 51.28 × 104 Mg in 1990–2000, 42.90 × 104 Mg in 2000–2009 and 36.15 × 104 Mg in 2009–2015, respectively. (3) There were three kinds of spatiotemporal patterns in the CBCS of this study area: high adjacent to the territorial land, low adjacent to the offshore waters in 1990; high in the central part, low in the peripheral areas in 2009 and 2015; and a mixed pattern in 2000. These patterns resulted from the different driving processes present in the different years. This study could serve as a blueprint for restoring and maintaining the CBCS of a megacity, to help mitigate the conflicts between socioeconomic development and the conservation of the CBCS, especially in the Shanghai coastal area.
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Affiliation(s)
- Wenbo Cai
- School of Design & China Institute for Urban Governance, Shanghai Jiao Tong University, Shanghai 200240, China; (W.C.); (Q.Z.)
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China;
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qing Zhu
- School of Design & China Institute for Urban Governance, Shanghai Jiao Tong University, Shanghai 200240, China; (W.C.); (Q.Z.)
| | - Meitian Chen
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China;
| | - Yongli Cai
- School of Design & China Institute for Urban Governance, Shanghai Jiao Tong University, Shanghai 200240, China; (W.C.); (Q.Z.)
- Correspondence:
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Duarte de Paula Costa M, Lovelock CE, Waltham NJ, Young M, Adame MF, Bryant CV, Butler D, Green D, Rasheed MA, Salinas C, Serrano O, York PH, Whitt AA, Macreadie PI. Current and future carbon stocks in coastal wetlands within the Great Barrier Reef catchments. Glob Chang Biol 2021; 27:3257-3271. [PMID: 33864332 DOI: 10.1111/gcb.15642] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 03/25/2021] [Accepted: 03/28/2021] [Indexed: 06/12/2023]
Abstract
Australia's Great Barrier Reef (GBR) catchments include some of the world's most intact coastal wetlands comprising diverse mangrove, seagrass and tidal marsh ecosystems. Although these ecosystems are highly efficient at storing carbon in marine sediments, their soil organic carbon (SOC) stocks and the potential changes resulting from climate impacts, including sea level rise are not well understood. For the first time, we estimated SOC stocks and their drivers within the range of coastal wetlands of GBR catchments using boosted regression trees (i.e. a machine learning approach and ensemble method for modelling the relationship between response and explanatory variables) and identified the potential changes in future stocks due to sea level rise. We found levels of SOC stocks of mangrove and seagrass meadows have different drivers, with climatic variables such as temperature, rainfall and solar radiation, showing significant contributions in accounting for variation in SOC stocks in mangroves. In contrast, soil type accounted for most of the variability in seagrass meadows. Total SOC stock in the GBR catchments, including mangroves, seagrass meadows and tidal marshes, is approximately 137 Tg C, which represents 9%-13% of Australia's total SOC stock while encompassing only 4%-6% of the total extent of Australian coastal wetlands. In a global context, this could represent 0.5%-1.4% of global SOC stock. Our study suggests that landward migration due to projected sea level rise has the potential to enhance carbon accumulation with total carbon gains between 0.16 and 0.46 Tg C and provides an opportunity for future restoration to enhance blue carbon.
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Affiliation(s)
- Micheli Duarte de Paula Costa
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Vic, Australia
- School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
| | - Catherine E Lovelock
- School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
| | - Nathan J Waltham
- Centre for Tropical Water and Aquatic Ecosystem Research, College of Science and Engineering, James Cook University, Cairns, Qld, Australia
| | - Mary Young
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Warrnambool, Vic, Australia
| | - Maria F Adame
- Australian Rivers Institute, Griffith University, Nathan, Qld, Australia
| | - Catherine V Bryant
- Centre for Tropical Water and Aquatic Ecosystem Research, College of Science and Engineering, James Cook University, Cairns, Qld, Australia
| | - Don Butler
- Department of Environment and Science, Brisbane, Qld, Australia
| | - David Green
- Research Computing Centre, The University of Queensland, St. Lucia, Qld, Australia
| | - Michael A Rasheed
- Centre for Tropical Water and Aquatic Ecosystem Research, College of Science and Engineering, James Cook University, Cairns, Qld, Australia
| | - Cristian Salinas
- School of Science & Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
| | - Oscar Serrano
- School of Science & Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
- Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain
| | - Paul H York
- Centre for Tropical Water and Aquatic Ecosystem Research, College of Science and Engineering, James Cook University, Cairns, Qld, Australia
| | - Ashley A Whitt
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Vic, Australia
| | - Peter I Macreadie
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Vic, Australia
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Wesselmann M, Geraldi NR, Duarte CM, Garcia-Orellana J, Díaz-Rúa R, Arias-Ortiz A, Hendriks IE, Apostolaki ET, Marbà N. Seagrass (Halophila stipulacea) invasion enhances carbon sequestration in the Mediterranean Sea. Glob Chang Biol 2021; 27:2592-2607. [PMID: 33843114 DOI: 10.1111/gcb.15589] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
The introduction and establishment of exotic species often result in significant changes in recipient communities and their associated ecosystem services. However, usually the magnitude and direction of the changes are difficult to quantify because there is no pre-introduction data. Specifically, little is known about the effect of marine exotic macrophytes on organic carbon sequestration and storage. Here, we combine dating sediment cores (210 Pb) with sediment eDNA fingerprinting to reconstruct the chronology of pre- and post-arrival of the Red Sea seagrass Halophila stipulacea spreading into the Eastern Mediterranean native seagrass meadows. We then compare sediment organic carbon storage and burial rates before and after the arrival of H. stipulacea and between exotic (H. stipulacea) and native (C. nodosa and P. oceanica) meadows since the time of arrival following a Before-After-Control-Impact (BACI) approach. This analysis revealed that H. stipulacea arrived at the areas of study in Limassol (Cyprus) and West Crete (Greece) in the 1930s and 1970s, respectively. Average sediment organic carbon after the arrival of H. stipulacea to the sites increased in the exotic meadows twofold, from 8.4 ± 2.5 g Corg m-2 year-1 to 14.7 ± 3.6 g Corg m-2 year-1 , and, since then, burial rates in the exotic seagrass meadows were higher than in native ones of Cymodocea nodosa and Posidonia oceanica. Carbon isotopic data indicated a 50% increase of the seagrass contribution to the total sediment Corg pool since the arrival of H. stipulacea. Our results demonstrate that the invasion of H. stipulacea may play an important role in maintaining the blue carbon sink capacity in the future warmer Mediterranean Sea, by developing new carbon sinks in bare sediments and colonizing areas previously occupied by the colder thermal affinity P. oceanica.
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Affiliation(s)
- Marlene Wesselmann
- Global Change Research Group, IMEDEA (CSIC-UIB), Institut Mediterrani d'Estudis Avançats, Esporles, Spain
| | - Nathan R Geraldi
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Jordi Garcia-Orellana
- Institut de Ciència i Tecnologia Ambientals (ICTA), Universitat Autònoma de Barcelona, Bellaterra, Spain
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Rubén Díaz-Rúa
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Ariane Arias-Ortiz
- Ecosystem Science Division, Department of Environmental Science, Policy and Management, University of California, Berkeley, Berkeley, CA, USA
- Institute of Marine Science, University of California, Santa Cruz, CA, USA
| | - Iris E Hendriks
- Global Change Research Group, IMEDEA (CSIC-UIB), Institut Mediterrani d'Estudis Avançats, Esporles, Spain
| | - Eugenia T Apostolaki
- Institute of Oceanography, Hellenic Centre for Marine Research, Heraklion, Greece
| | - Núria Marbà
- Global Change Research Group, IMEDEA (CSIC-UIB), Institut Mediterrani d'Estudis Avançats, Esporles, Spain
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49
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Adame MF, Connolly RM, Turschwell MP, Lovelock CE, Fatoyinbo T, Lagomasino D, Goldberg LA, Holdorf J, Friess DA, Sasmito SD, Sanderman J, Sievers M, Buelow C, Kauffman JB, Bryan‐Brown D, Brown CJ. Future carbon emissions from global mangrove forest loss. Glob Chang Biol 2021; 27:2856-2866. [PMID: 33644947 PMCID: PMC8251893 DOI: 10.1111/gcb.15571] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 02/15/2021] [Indexed: 05/28/2023]
Abstract
Mangroves have among the highest carbon densities of any tropical forest. These 'blue carbon' ecosystems can store large amounts of carbon for long periods, and their protection reduces greenhouse gas emissions and supports climate change mitigation. Incorporating mangroves into Nationally Determined Contributions to the Paris Agreement and their valuation on carbon markets requires predicting how the management of different land-uses can prevent future greenhouse gas emissions and increase CO2 sequestration. We integrated comprehensive global datasets for carbon stocks, mangrove distribution, deforestation rates, and land-use change drivers into a predictive model of mangrove carbon emissions. We project emissions and foregone soil carbon sequestration potential under 'business as usual' rates of mangrove loss. Emissions from mangrove loss could reach 2391 Tg CO2 eq by the end of the century, or 3392 Tg CO2 eq when considering foregone soil carbon sequestration. The highest emissions were predicted in southeast and south Asia (West Coral Triangle, Sunda Shelf, and the Bay of Bengal) due to conversion to aquaculture or agriculture, followed by the Caribbean (Tropical Northwest Atlantic) due to clearing and erosion, and the Andaman coast (West Myanmar) and north Brazil due to erosion. Together, these six regions accounted for 90% of the total potential CO2 eq future emissions. Mangrove loss has been slowing, and global emissions could be more than halved if reduced loss rates remain in the future. Notably, the location of global emission hotspots was consistent with every dataset used to calculate deforestation rates or with alternative assumptions about carbon storage and emissions. Our results indicate the regions in need of policy actions to address emissions arising from mangrove loss and the drivers that could be managed to prevent them.
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Affiliation(s)
- Maria F. Adame
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
| | - Rod M. Connolly
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
| | | | | | | | - David Lagomasino
- Department of Coastal StudiesEast Carolina UniversityWancheseNCUSA
| | - Liza A. Goldberg
- Earth System Science Interdisciplinary CenterUniversity of MarylandCollege ParkMDUSA
| | - Jordan Holdorf
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
| | - Daniel A. Friess
- Department of GeographyNational University of SingaporeSingaporeSingapore
- Mangrove Specialist GroupCentre for Nature‐based Climate Solutions, National University of SingaporeSingaporeSingapore
| | - Sigit D. Sasmito
- Research Institute for Environment and LivelihoodsCharles Darwin UniversityCasuarinaNTAustralia
- Center for International Forestry ResearchBogorIndonesia
- NUS Environmental Research InstituteNational University of SingaporeSingaporeSingapore
| | | | - Michael Sievers
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
| | - Christina Buelow
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
| | - J. Boone Kauffman
- Department of Fisheries, Wildlife and Conservation SciencesOregon State UniversityCorvallisORUSA
| | - Dale Bryan‐Brown
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
| | - Christopher J. Brown
- Australian Rivers InstituteGriffith UniversityNathanQldAustralia
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQldAustralia
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50
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Xia S, Wang W, Song Z, Kuzyakov Y, Guo L, Van Zwieten L, Li Q, Hartley IP, Yang Y, Wang Y, Andrew Quine T, Liu C, Wang H. Spartina alterniflora invasion controls organic carbon stocks in coastal marsh and mangrove soils across tropics and subtropics. Glob Chang Biol 2021; 27:1627-1644. [PMID: 33432697 DOI: 10.1111/gcb.15516] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 12/24/2020] [Indexed: 06/12/2023]
Abstract
Coastal wetlands are among the most productive ecosystems and store large amounts of organic carbon (C)-the so termed "blue carbon." However, wetlands in the tropics and subtropics have been invaded by smooth cordgrass (Spartina alterniflora) affecting storage of blue C. To understand how S. alterniflora affects soil organic carbon (SOC) stocks, sources, stability, and their spatial distribution, we sampled soils along a 2500 km coastal transect encompassing tropical to subtropical climate zones. This included 216 samplings within three coastal wetland types: a marsh (Phragmites australis) and two mangroves (Kandelia candel and Avicennia marina). Using δ13 C, C:nitrogen (N) ratios, and lignin biomarker composition, we traced changes in the sources, stability, and storage of SOC in response to S. alterniflora invasion. The contribution of S. alterniflora-derived C up to 40 cm accounts for 5.6%, 23%, and 12% in the P. australis, K. candel, and A. marina communities, respectively, with a corresponding change in SOC storage of +3.5, -14, and -3.9 t C ha-1 . SOC storage did not follow the trend in aboveground biomass from the native to invasive species, or with vegetation types and invasion duration (7-15 years). SOC storage decreased with increasing mean annual precipitation (1000-1900 mm) and temperature (15.3-23.4℃). Edaphic variables in P. australis marshes remained stable after S. alterniflora invasion, and hence, their effects on SOC content were absent. In mangrove wetlands, however, electrical conductivity, total N and phosphorus, pH, and active silicon were the main factors controlling SOC stocks. Mangrove wetlands were most strongly impacted by S. alterniflora invasion and efforts are needed to focus on restoring native vegetation. By understanding the mechanisms and consequences of invasion by S. alterniflora, changes in blue C sequestration can be predicted to optimize storage can be developed.
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Affiliation(s)
- Shaopan Xia
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
- Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Weiqi Wang
- Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Zhaoliang Song
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
- Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Yakov Kuzyakov
- Tianjin Key Laboratory of Water Resources and Environment, & School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin, China
- Department of Soil Science of Temperate Ecosystems, University of Goettingen, Goettingen, Germany
- Department of Agricultural Soil Science, University of Goettingen, Goettingen, Germany
- Agro-Technological Institute, RUDN University, Moscow, Russia
| | - Laodong Guo
- School of Freshwater Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | | | - Qiang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
- Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Iain P Hartley
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Yidong Wang
- Tianjin Key Laboratory of Water Resources and Environment, & School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin, China
| | | | - Congqiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
- Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, China
| | - Hailong Wang
- School of Environment and Chemical Engineering, Foshan University, Foshan, Guangdong, China
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, Zhejiang, China
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