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Qu Y, Zhao Y, Yao X, Wang J, Liu Z, Hong Y, Zheng P, Wang L, Hu B. Salinity causes differences in stratigraphic methane sources and sinks. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 19:100334. [PMID: 38046178 PMCID: PMC10692758 DOI: 10.1016/j.ese.2023.100334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 10/09/2023] [Accepted: 10/12/2023] [Indexed: 12/05/2023]
Abstract
Methane metabolism, driven by methanogenic and methanotrophic microorganisms, plays a pivotal role in the carbon cycle. As seawater intrusion and soil salinization rise due to global environmental shifts, understanding how salinity affects methane emissions, especially in deep strata, becomes imperative. Yet, insights into stratigraphic methane release under varying salinity conditions remain sparse. Here we investigate the effects of salinity on methane metabolism across terrestrial and coastal strata (15-40 m depth) through in situ and microcosm simulation studies. Coastal strata, exhibiting a salinity level five times greater than terrestrial strata, manifested a 12.05% decrease in total methane production, but a staggering 687.34% surge in methane oxidation, culminating in 146.31% diminished methane emissions. Salinity emerged as a significant factor shaping the methane-metabolizing microbial community's dynamics, impacting the methanogenic archaeal, methanotrophic archaeal, and methanotrophic bacterial communities by 16.53%, 27.25%, and 22.94%, respectively. Furthermore, microbial interactions influenced strata system methane metabolism. Metabolic pathway analyses suggested Atribacteria JS1's potential role in organic matter decomposition, facilitating methane production via Methanofastidiosales. This study thus offers a comprehensive lens to comprehend stratigraphic methane emission dynamics and the overarching factors modulating them.
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Affiliation(s)
- Ying Qu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Yuxiang Zhao
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Xiangwu Yao
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Jiaqi Wang
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Zishu Liu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Yi Hong
- Ocean College, Zhejiang University, Zhoushan, China
| | - Ping Zheng
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
| | - Lizhong Wang
- Ocean College, Zhejiang University, Zhoushan, China
| | - Baolan Hu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, China
- Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, China
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2
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Hu M, Yan R, Ni R, Wu H. Coastal degradation regulates the availability and diffusion kinetics of phosphorus at the sediment-water interface: Mechanisms and environmental implications. WATER RESEARCH 2024; 250:121086. [PMID: 38171179 DOI: 10.1016/j.watres.2023.121086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 12/09/2023] [Accepted: 12/27/2023] [Indexed: 01/05/2024]
Abstract
Coastal wetlands have experienced considerable loss and degradation globally. However, how coastal degradation regulates sediment phosphorus (P) transformation and its underlying mechanisms remain largely unknown in subtropical coastal ecosystems. This study conducted seasonal field measurements using high-resolution diffusive gradient in thin films (DGT) and dialysis (Peeper) techniques, as well as a DGT-induced fluxes in sediments (DIFS) model, to evaluate the mobilization and diffusion of P along a degradation gradient ranging from pristine wetlands to moderately and severely degraded sites. We observed that sediment P is diminished by coastal degradation, and severely degraded sites exhibit a decline in the concentration of available P, despite the presence of distinct seasonal patterns. High-resolution data based on DGT/Peeper analysis revealed that labile P and soluble reactive P (SRP) concentrations varied from 0.0006 mg L-1 to 0.084 mg L-1 (mean 0.0147 mg L-1) and from 0.0128 mg L-1 to 0.1677 mg L-1 (mean 0.0536 mg L-1), respectively. Coastal degradation had a substantial impact on increasing SRP and labile P concentrations, particularly at severely degraded sites. Although severely degraded wetlands appeared to be P sinks (negative P flux at these sites), we did also observe positive diffusive flux in October, indicating that coastal degradation may accelerate the diffusion and remobilization of sediment P into overlying water. The simulations of the DIFS model provided compelling proof of the high resupply capacity of sediment P at severely degraded sites, as supported by the increased R and k-1 values but decreased Tc values. Taken together, these results suggest coastal degradation reduces the sediment P pool, primarily attributed to the strong remobilization of P from the sediment to porewater and overlying water by enhancing the resupply capability and diffusion kinetics. This acceleration induces nutrient loss which adversely impacts the water quality of the surrounding ecosystem. To reduce the adverse effects of coastal degradation, it is essential to adopt a combination of conservation, restoration, and management efforts designed to mitigate the risk of internal P loading and release, and ultimately maintain a regional nutrient balance.
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Affiliation(s)
- Minjie Hu
- Key Laboratory of Humid Sub-tropical Eco-geographical Processes of Ministry of Education, Fujian Normal University, Fuzhou 350117, China; School of Geographical Sciences, Fujian Normal University, Fuzhou 350117, China; Wetland Ecosystem Research Station of Minjiang Estuary, National Forestry and Grassland Administration, Fuzhou 350215, China.
| | - Ruibing Yan
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350117, China
| | - Ranxu Ni
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350117, China
| | - Hui Wu
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350117, China
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3
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Gong JC, Li BH, Hu JW, Ding XJ, Liu CY, Yang GP. Tidal effects on carbon dioxide emission dynamics in intertidal wetland sediments. ENVIRONMENTAL RESEARCH 2023; 238:117110. [PMID: 37696322 DOI: 10.1016/j.envres.2023.117110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/01/2023] [Accepted: 09/08/2023] [Indexed: 09/13/2023]
Abstract
Understanding the control mechanisms of carbon dioxide (CO2) emissions in intertidal wetland sediments is beneficial for the concern of global carbon biogeochemistry and climate change. Nevertheless, multiple controls on CO2 emissions from intertidal wetland sediments to the atmosphere still need to be clarified. This study investigated the effect of tidal action on CO2 emissions from salt marsh sediments covered by Spartina alterniflora in the Jiaozhou Bay wetland using the static chamber method combined with an infrared CO2 detector. The results showed that the CO2 emission fluxes from the sediment during ebb tides were higher than those during flood tides. The whole wetland sediment acted as a weak source of atmospheric CO2 (average flux: 24.44 ± 16.80 mg C m-2 h-1) compared to terrestrial soils and was affected by the cycle of seawater inundation and exposure. The tidal influence on vertical dissolved inorganic carbon (DIC) transport in the sediment was also quantitated using a two-end member mixing model. The surface sediment layer (5-15 cm) with maximum DIC concentration during ebb tides became the one with minimum DIC concentration during flood tides, indicating the DIC transport from the surface sediment to seawater. Furthermore, aerobic respiration by microorganisms was the primary process of CO2 production in the sediment according to 16 S rDNA sequencing analysis. This study revealed the strong impact of tidal action on CO2 emissions from the wetland sediment and provided insights into the source-sink pattern of CO2 and DIC at the land-ocean interface.
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Affiliation(s)
- Jiang-Chen Gong
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
| | - Bing-Han Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Jing-Wen Hu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China
| | - Xi-Ju Ding
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Chun-Ying Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
| | - Gui-Peng Yang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
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N RH, Tait DR, Nandan SB. Land use drives large CH 4 fluxes from a highly urbanized Indian estuary. MARINE POLLUTION BULLETIN 2023; 196:115594. [PMID: 37797539 DOI: 10.1016/j.marpolbul.2023.115594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/22/2023] [Accepted: 09/24/2023] [Indexed: 10/07/2023]
Abstract
There is growing awareness of the need to better constrain the contribution of atmospheric methane (CH4) fluxes from urbanized estuaries due to the high global warming potential of CH4 and the accelerating growth of urban expansion. This study undertook seasonal sampling campaigns to understand the impact of urbanization on atmospheric CH4 fluxes and their drivers in a large, tropical estuary in India. Overall, the study found that the Cochin estuary emitted large amounts of CH4 (398.8 ± 141.6 μmolm-2d-1) to the atmosphere with CH4 hotspots reaching up to 939.7 μmolm-2d-1 were identified. The strongest drivers of CH4 dynamics in different anthropogenically impacted zones were traced. The source of organic matter for CH4 production was revealed to be terrestrial C3 plants, autochthonous production, marine phytoplankton, and sewage inputs. The study suggests that monsoonal urbanized tropical estuaries may be an important but under-recognized element of the global CH4 budget.
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Affiliation(s)
- Regina Hershey N
- Dept. of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Cochin 682 016, India; Dept. of Zoology, Bharata Mata College, Thrikkakara, Cochin 682 021, India.
| | - Douglas R Tait
- Faculty of Science and Engineering, Southern Cross University, Lismore, New South Wales 2480, Australia.
| | - S Bijoy Nandan
- Dept. of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Cochin 682 016, India.
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Xie M, Qian L, Dong H, Mei W, Fu X, Hu Y, Yan J, Sun Y, Wu P, Chen X, Wang L. The high organic carbon accumulation in estuarine wetlands necessarily does not represent a high CO 2 sequestration capacity. ENVIRONMENT INTERNATIONAL 2023; 172:107762. [PMID: 36689865 DOI: 10.1016/j.envint.2023.107762] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/04/2023] [Accepted: 01/17/2023] [Indexed: 06/17/2023]
Abstract
Estuarine wetlands with high organic carbon (OC) accumulation rates due to their high plant biomass and interception of tide-derived OC are generally considered as large CO2 sinks. However, our previous study found that tidal OC input seems to stimulate soil CO2 emissions, potentially weakening CO2 sequestration in estuarine wetlands. To further verify this phenomenon, we first established a structural equation model, which confirmed a positive correlation between tidal OC input and soil organic carbon (SOC) and soil respiration. We then performed trace analysis to determine the stability of SOC derived from different sources and its effect on soil CO2 emissions by analyzing the input and retention of OC derived from tides and plants in the Yangtze Estuary wetlands. From upstream to downstream, as tidal OC input decreased, the relative retention ratio of the tidal OC in wetland soil increased from 1.259 to 2.148, whereas the relative retention ratio of plant OC in the soil decreased from 61.5% to 14.8%. Our findings indicated that the degradability of tidal OC was higher upstream than that downstream, but both inhibited plant OC degradation, thus providing an important reason for the higher CO2 emissions upstream of wetlands (with higher tidal OC input). In addition, the primarily contributor to CO2 (δ13) emissions' transforming from plant SOC (81.35%) to tidal SOC (91.18%) was an increase in organic matter input from the tide in a microcosm system. Consequently, a higher CO2 output than CO2 input (plant OC) due to the ready degradation of tidal OC consequently weakens the CO2 sequestration capacity of the estuarine wetlands. This phenomenon is cause for concern regarding the CO2 sink function of estuarine wetlands intercepting large amounts of organic matter.
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Affiliation(s)
- Mengdi Xie
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Liwei Qian
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Research Department of Energy and Eco-Environment, Zhejiang Development & Planning Institute, Hangzhou 310030, China
| | - Haoyu Dong
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Wenxuan Mei
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xiaohua Fu
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Yu Hu
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jianfang Yan
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Ying Sun
- Shanghai Jiuduansha Wetland Nature Reserve Management Center, Shanghai 200135, China
| | - Pengfei Wu
- Shanghai Jiuduansha Wetland Nature Reserve Management Center, Shanghai 200135, China
| | - Xiuzhi Chen
- Shanghai Jiuduansha Wetland Nature Reserve Management Center, Shanghai 200135, China
| | - Lei Wang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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6
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Pozo-Solar F, Cornejo-D´Ottone M, Orellana R, Yepsen DV, Bassi N, Salcedo-Castro J, Aguilar-Muñoz P, Molina V. Dissolved greenhouse gases and benthic microbial communities in coastal wetlands of the Chilean coast semiarid region. PLoS One 2022; 17:e0271208. [PMID: 36174070 PMCID: PMC9522034 DOI: 10.1371/journal.pone.0271208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 06/25/2022] [Indexed: 11/18/2022] Open
Abstract
Coastal wetlands are ecosystems associated with intense carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) recycling, modulated by salinity and other environmental factors that influence the microbial community involved in greenhouse gases production and consumption. In this study, we evaluated the influence of environmental factors on GHG concentration and benthic microbial community composition in coastal wetlands along the coast of the semiarid region. Wetlands were situated in landscapes along a south-north gradient of higher aridity and lower anthropogenic impact. Our results indicate that wetlands have a latitudinal variability associated with higher organic matter content at the north, especially in summer, and higher nutrient concentration at the south, predominantly in winter. During our sampling, wetlands were characterized by positive CO2 μM and CH4 nM excess, and a shift of N2O nM excess from negative to positive values from the north to the south. Benthic microbial communities were taxonomically diverse with > 60 phyla, especially in low frequency taxa. Highly abundant bacterial phyla were classified into Gammaproteobacteria (Betaproteobacteria order), Alphaproteobacteria and Deltaproteobacteria, including key functional groups such as nitrifying and methanotrophic bacteria. Generalized additive model (GAM) indicated that conductivity accounted for the larger variability of CH4 and CO2, but the predictions of CH4 and CO2 concentration were improved when latitude and pH concentration were included. Nitrate and latitude were the best predictors to account for the changes in the dissolved N2O distribution. Structural equation modeling (SEM), illustrated how the environment significantly influences functional microbial groups (nitrifiers and methane oxidizers) and their resulting effect on GHG distribution. Our results highlight the combined role of salinity and substrates of key functional microbial groups with metabolisms associated with both carbon and nitrogen, influencing dissolved GHG and their potential exchange in natural and anthropogenically impacted coastal wetlands.
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Affiliation(s)
- Francisco Pozo-Solar
- Programa de Doctorado Interdisciplinario en Ciencias Ambientales, Universidad de Playa Ancha, Valparaíso, Chile
- Departamento de Ciencias y Geografía, Universidad de Playa Ancha, Valparaíso, Chile
- HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Marcela Cornejo-D´Ottone
- Escuela de Ciencias del Mar and Instituto Milenio de Oceanografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Roberto Orellana
- Departamento de Ciencias y Geografía, Universidad de Playa Ancha, Valparaíso, Chile
- HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Daniela V. Yepsen
- Programa de Doctorado en Ciencias con Mención en Manejo de Recursos Acuáticos Renovables (MaReA), Universidad de Concepción, Barrio Universitario s/n, Universidad de Concepción, Concepción, Chile
| | - Nickolas Bassi
- Departamento de Geografía, Universidad de Playa Ancha, Avenida Leopoldo Carvallo Valparaíso, Chile
| | - Julio Salcedo-Castro
- School of Earth and Atmospheric Sciences, Faculty of Science, Queensland University of Technology, Brisbane, Queensland, Australia
- Sino-Australian Research Consortium for Coastal Management, School of Science, University of New South Wales, Canberra, Australia
| | | | - Verónica Molina
- Departamento de Ciencias y Geografía, Universidad de Playa Ancha, Valparaíso, Chile
- HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
- Centro de Investigación Oceanográfica COPAS COASTAL, Universidad de Concepción, Concepción, Chile
- * E-mail:
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Peng Y, Zhou C, Jin Q, Ji M, Wang F, Lai Q, Shi R, Xu X, Chen L, Wang G. Tidal variation and litter decomposition co-affect carbon emissions in estuarine wetlands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 839:156357. [PMID: 35640748 DOI: 10.1016/j.scitotenv.2022.156357] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 05/26/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Estuarine wetlands play important roles in the regional and global carbon cycle as well as greenhouse gas emissions; however, the driving factors and potential carbon emissions mechanisms are unclear. Here, the carbon emission fluxes were investigated in situ from different vegetated areas in the Chongming wetlands. The results showed that the highest methane (CH4) and carbon dioxide (CO2) emissions of 178.1 and 21,482.5 mg∙m-2∙min-1 were in Scirpus mariqueter and Phragmites australis dominated areas, respectively. A series of microcosms was strategically designed to simulate the influence of tidal variation on carbon emissions and the litter decomposition on daily- and monthly-timescales in estuarine wetlands. All added litter promoted CH4 and CO2 emissions from the wetland soils. The CH4 and CO2 emission fluxes of the S. mariqueter treatment were higher (367.7 vs. 108.4; 1607.9 vs. 1324.3 mg∙m-2∙min-1) than those of the P. australis treatment without tidal variation on a monthly timescale, due to the higher total organic carbon (TOC) content of S. mariqueter. The decomposition of litter also released a large amount of nutrients, which enhanced the abundance of methane-producing archaea (MPA) and methane-oxidizing bacteria (MOB). However, the tidal water level was negatively correlated with CH4 and CO2 emission fluxes. The CH4 and CO2 emission fluxes in the S. mariqueter treatment at the lowest tide were 556.02 and 604.99 mg∙m-2∙min-1, respectively. However, the CH4 and CO2 emission fluxes did not change significantly on the daily timescale in the S. mariqueter treatment without tidal variations. Therefore, the prolonged timescales revealed increases in litter decomposition but a decrease in the contribution of tidal variations to carbon emissions in estuarine wetlands. These findings provide a theoretical basis for evaluating the carbon cycle in estuarine wetlands.
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Affiliation(s)
- Yu Peng
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Chuanqiao Zhou
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Qiu Jin
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Ming Ji
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Feiyu Wang
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Qian Lai
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Ruijie Shi
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
| | - Xiaoguang Xu
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China.
| | - Liangang Chen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Guoxiang Wang
- School of Environment, Nanjing Normal University, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210023, China
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8
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Verma K, Pandey J. Collateral implications of carbon and metal pollution on carbon dioxide emission at land-water interface of the Ganga River. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:24203-24218. [PMID: 34822092 DOI: 10.1007/s11356-021-17729-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Atmospheric CO2 source and sink is among the most debated issues that have puzzled climate change geochemist for decades. Here, we tested whether heavy metal pollutants in river sediments favor preservation of organic matter through shielding microbial degradation. We measured CO2 emission and extracellular enzyme activities at land-water interface (LWI) of 7 sites along a 285 km main stem of the Ganga River and 60 locations up- and downstream of two contrasting point sources discharging urban (Assi drain; Asdr) and industrial (Ramnagar drain; Rmdr) wastewaters to the river. We found the lowest CO2 flux at Rmdr mouth characterized by the highest concentrations of Cu, Cr, Zn, Pb, Ni, and Cd. The fluxes were relatively higher at locations up- and downstream Rmdr. Substrate induced respiration (SIR), protease, FDAase, and β-D-glucosidase all showed a similar trend, but phenol oxidase and alkaline phosphatase showed opposite trend at the main river stem and Asdr. Sites rich in terrestrially derived organic matter have high phenol oxidase activity with low CO2 emission. The CO2 emission in the main river stem showed curvilinear relationships with total heavy metals (∑THM; R2 = 0.68; p < 0.001) and TOC (R2 = 0.65; p < 0.001). The dynamic fit model of main stem data showed that the ∑THM above 337.4 µg g-1 were able to significantly decrease the activities of protease, FDAase, and β-D-glucosidase. The study has implications for understanding C-cycling in human-impacted river sediments where metal pollution shields microbial degradation consequently carbon and nutrient release and merits attention towards river management decisions.
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Affiliation(s)
- Kavita Verma
- Ganga River Ecology Research Laboratory, Environmental Science Division, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Jitendra Pandey
- Ganga River Ecology Research Laboratory, Environmental Science Division, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.
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9
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Cui H, Bai J, Du S, Wang J, Keculah GN, Wang W, Zhang G, Jia J. Interactive effects of groundwater level and salinity on soil respiration in coastal wetlands of a Chinese delta. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117400. [PMID: 34058447 DOI: 10.1016/j.envpol.2021.117400] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/03/2021] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
Coastal wetland soils serve as a great C sink or source, which highly depends on soil carbon flux affected by complex hydrology in relation to salinity. We conducted a field experiment to investigate soil respiration of three coastal wetlands with different land covers (BL: bare land; SS: Suaeda salsa; PL: Phragmites australis) from May to October in 2012 and 2013 under three groundwater tables (deeper, medium, and shallower water tables) in the Yellow River Delta of China, and to characterize the spatial and temporal changes and the primary environmental drivers of soil respiration in coastal wetlands. Our results showed that the elevated groundwater table decreased soil CO2 emissions, and the soil respiration rates at each groundwater table exhibited seasonal and diurnal dynamics, where significant differences were observed among coastal wetlands with different groundwater tables (p < 0.05), with the average CO2 emission of 146.52 ± 13.66 μmol m-2s-1 for deeper water table wetlands, 105.09 ± 13.48 μmol m-2s-1 for medium water table wetlands and 54.32 ± 10.02 μmol m-2s-1 for shallower water table wetlands. Compared with bare land and Suaeda salsa wetlands, higher soil respiration was observed in Phragmites australis wetlands. Generally, soil respiration was greatly affected by salinity and soil water content. There were significant correlations between groundwater tables, electrical conductivity and soil respiration (p < 0.05), indicating that soil respiration in coastal wetlands was limited by electrical conductivity and groundwater tables and soil C sink might be improved by regulating water and salt conditions. We have also observed that soil respiration and temperature showed an exponential relationship on a seasonal scale. Taking into consideration the changes in groundwater tables and salinity that might be caused by sea level rise in the context of global warming, we emphasize the importance of groundwater level and salinity in the carbon cycle process of estuarine wetlands in the future.
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Affiliation(s)
- Hao Cui
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Junhong Bai
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
| | - Shudong Du
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Junjing Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Ghemelee Nitta Keculah
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Wei Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Guangliang Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Jia Jia
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
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10
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Abstract
Methane (CH4) emissions from estuarine wetlands were proved to be influenced by tide movement and inundation conditions notably in many previous studies. Although there have been several researches focusing on the seasonal or annual CH4 emissions, the short-term CH4 emissions during the tide cycles were rarely studied up to now in this area. In order to investigate the CH4 emission pattern during a tide cycle in Yangtze Estuary salt marshes, frequent fixed-point observations of methane flux were carried out using the in-situ static closed chamber technique. The results indicated that the daily average CH4 fluxes varied from 0.68 mgCH4·m−2·h−1 to 4.22 mgCH4·m−2·h−1 with the average flux reaching 1.78 mgCH4·m−2·h−1 from small tide to spring tide in summer. CH4 fluxes did not show consistent variation with both tide levels and inundation time but increased steadily during almost the whole research period. By Pearson correlation analysis, CH4 fluxes were not correlated with both tide levels (R = −0.014, p = 0.979) and solar radiation (R = 0.024, p = 0.865), but significantly correlated with ambient temperature. It is temperature rather than the tide level mainly controlling CH4 emissions during the tide cycles. Besides, CH4 fluxes also showed no significant correlation with the underground pore-water CH4 concentrations, indicating that plant-mediated transport played a more important role in CH4 fluxes compared with its production and consumption.
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11
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Carbon Balance in Salt Marsh and Mangrove Ecosystems: A Global Synthesis. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2020. [DOI: 10.3390/jmse8100767] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Mangroves and salt marshes are among the most productive ecosystems in the global coastal ocean. Mangroves store more carbon (739 Mg CORG ha−1) than salt marshes (334 Mg CORG ha−1), but the latter sequester proportionally more (24%) net primary production (NPP) than mangroves (12%). Mangroves exhibit greater rates of gross primary production (GPP), aboveground net primary production (AGNPP) and plant respiration (RC), with higher PGPP/RC ratios, but salt marshes exhibit greater rates of below-ground NPP (BGNPP). Mangroves have greater rates of subsurface DIC production and, unlike salt marshes, exhibit active microbial decomposition to a soil depth of 1 m. Salt marshes release more CH4 from soil and creek waters and export more dissolved CH4, but mangroves release more CO2 from tidal waters and export greater amounts of particulate organic carbon (POC), dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC), to adjacent waters. Both ecosystems contribute only a small proportion of GPP, RE (ecosystem respiration) and NEP (net ecosystem production) to the global coastal ocean due to their small global area, but contribute 72% of air–sea CO2 exchange of the world’s wetlands and estuaries and contribute 34% of DIC export and 17% of DOC + POC export to the world’s coastal ocean. Thus, both wetland ecosystems contribute disproportionately to carbon flow of the global coastal ocean.
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12
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Hu M, Sardans J, Yang X, Peñuelas J, Tong C. Patterns and environmental drivers of greenhouse gas fluxes in the coastal wetlands of China: A systematic review and synthesis. ENVIRONMENTAL RESEARCH 2020; 186:109576. [PMID: 32361080 DOI: 10.1016/j.envres.2020.109576] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
Coastal wetlands play an increasingly important role in regulating greenhouse gas (GHG) fluxes and thus affecting climate change. However, the overall magnitude, trend, and environmental drivers of GHG fluxes in these wetlands of China remain uncertain. Herein, we synthesized data from 70 publications involving 187 field observations to identify patterns and drivers of GHG fluxes across coastal wetlands in China. Average methane (CH4), nitrous oxide (N2O) fluxes, and carbon dioxide (CO2) emissions (ecosystem respiration) across coastal wetlands were estimated as 2.20±0.31 mg·m-2·h-1, 16.44±2.96 μg·m-2·h-1, and 388.76±42.28 mg·m-2·h-1, respectively. GHG emissions varied with tidal inundation, where CH4 and CO2 emissions during tidal inundation were lower than during ebbing. CH4 and CO2 emissions from wetlands decreased linearly with increasing latitude, while N2O did not. CH4 fluxes were positively related to air temperature and aboveground biomass, and CO2 emissions were positively related to soil organic carbon. N2O fluxes were lower with increasing soil pH, and CH4 and CO2 emissions were greater with increasing soil moisture. Based on the results of sustained-flux global warming potential and sustained-flux global cooling potential models, our paper indicate that the fluxes of CH4 and N2O in coastal wetlands have a positive feedback to global warming, which is mainly driven by the CH4 emission. Our synthesis improved understanding of the roles of coastal wetlands in the ecosystem C cycle under global change. We suggest that long-term field observations of GHG fluxes across a wider range of spatiotemporal scales are urgently required to improve the prediction accuracy in GHG fluxes and the assessment of net GHG balance and its contribution to the GWP of coastal wetlands.
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Affiliation(s)
- Minjie Hu
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou, 350007, Fujian, China; College of the Environment and Ecology, Xiamen University, Xiamen, 361102, Fujian, China.
| | - Jordi Sardans
- CSIC, Global Ecology CREAF-CSIC-UAB, Bellaterra, 08193, Barcelona, Catalonia, Spain; CREAF, Cerdanyola del Vallès, 08193, Barcelona, Catalonia, Spain
| | - Xianyu Yang
- School of Ecological and Environmental Science, East China Normal University, Shanghai, 200241, China
| | - Josep Peñuelas
- CSIC, Global Ecology CREAF-CSIC-UAB, Bellaterra, 08193, Barcelona, Catalonia, Spain; CREAF, Cerdanyola del Vallès, 08193, Barcelona, Catalonia, Spain
| | - Chuan Tong
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou, 350007, Fujian, China.
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13
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Tan L, Ge Z, Zhou X, Li S, Li X, Tang J. Conversion of coastal wetlands, riparian wetlands, and peatlands increases greenhouse gas emissions: A global meta-analysis. GLOBAL CHANGE BIOLOGY 2020; 26:1638-1653. [PMID: 31755630 DOI: 10.1111/gcb.14933] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
Land-use/land-cover change (LULCC) often results in degradation of natural wetlands and affects the dynamics of greenhouse gases (GHGs). However, the magnitude of changes in GHG emissions from wetlands undergoing various LULCC types remains unclear. We conducted a global meta-analysis with a database of 209 sites to examine the effects of LULCC types of constructed wetlands (CWs), croplands (CLs), aquaculture ponds (APs), drained wetlands (DWs), and pastures (PASs) on the variability in CO2 , CH4 , and N2 O emissions from the natural coastal wetlands, riparian wetlands, and peatlands. Our results showed that the natural wetlands were net sinks of atmospheric CO2 and net sources of CH4 and N2 O, exhibiting the capacity to mitigate greenhouse effects due to negative comprehensive global warming potentials (GWPs; -0.9 to -8.7 t CO2 -eq ha-1 year-1 ). Relative to the natural wetlands, all LULCC types (except CWs from coastal wetlands) decreased the net CO2 uptake by 69.7%-456.6%, due to a higher increase in ecosystem respiration relative to slight changes in gross primary production. The CWs and APs significantly increased the CH4 emissions compared to those of the coastal wetlands. All LULCC types associated with the riparian wetlands significantly decreased the CH4 emissions. When the peatlands were converted to the PASs, the CH4 emissions significantly increased. The CLs, as well as DWs from peatlands, significantly increased the N2 O emissions in the natural wetlands. As a result, all LULCC types (except PASs from riparian wetlands) led to remarkably higher GWPs by 65.4%-2,948.8%, compared to those of the natural wetlands. The variability in GHG fluxes with LULCC was mainly sensitive to changes in soil water content, water table, salinity, soil nitrogen content, soil pH, and bulk density. This study highlights the significant role of LULCC in increasing comprehensive GHG emissions from global natural wetlands, and our results are useful for improving future models and manipulative experiments.
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Affiliation(s)
- Lishan Tan
- State Key Laboratory of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, Shanghai, China
| | - Zhenming Ge
- State Key Laboratory of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, Shanghai, China
- Yangtze Delta Estuarine Wetland Ecosystem Observation and Research Station, Ministry of Education & Shanghai Science and Technology Committee, Shanghai, China
| | - Xuhui Zhou
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem Research, Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Shihua Li
- State Key Laboratory of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, Shanghai, China
| | - Xiuzhen Li
- State Key Laboratory of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, Shanghai, China
- Yangtze Delta Estuarine Wetland Ecosystem Observation and Research Station, Ministry of Education & Shanghai Science and Technology Committee, Shanghai, China
| | - Jianwu Tang
- State Key Laboratory of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, Shanghai, China
- Yangtze Delta Estuarine Wetland Ecosystem Observation and Research Station, Ministry of Education & Shanghai Science and Technology Committee, Shanghai, China
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14
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Hu M, Peñuelas J, Sardans J, Yang X, Tong C, Zou S, Cao W. Shifts in Microbial Biomass C/N/P Stoichiometry and Bacterial Community Composition in Subtropical Estuarine Tidal Marshes Along a Gradient of Freshwater–Oligohaline Water. Ecosystems 2019. [DOI: 10.1007/s10021-019-00468-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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15
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Hu M, Peñuelas J, Sardans J, Huang J, Li D, Tong C. Effects of nitrogen loading on emission of carbon gases from estuarine tidal marshes with varying salinity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 667:648-657. [PMID: 30833263 DOI: 10.1016/j.scitotenv.2019.02.429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/26/2019] [Accepted: 02/27/2019] [Indexed: 06/09/2023]
Abstract
Estuarine tidal marshes sequester significant quantities of carbon and are suffering from anthropogenic nitrogen (N) enhancement. However, the effects of this N loading on carbon gas emissions from freshwater-oligohaline tidal marshes are unknown. In this paper, we report on our evaluation of the effects of a N gradient (0, 24, 48 and 96 g NH4NO3-N m-2 y-1) on the methane (CH4) and carbon dioxide (CO2) emissions from freshwater and oligohaline tidal marshes in the Min River estuary, southeast China. On an annual scale, the oligohaline marsh has significantly higher CO2 emissions, while it has slightly lower CH4 emissions relative to freshwater marsh. The addition of N increased CH4 emission from the freshwater marsh and decreased CH4 emission from the oligohaline marsh, although there was no statistically significant difference in CH4 emission between either of the two marshes and the control. The addition of 96 g NH4NO3-N m-2 y-1 significantly increased CO2 emission from the freshwater marsh, while it did not significantly influence CO2 emission from the oligohaline marsh. CH4 and CO2 emission levels were positively correlated with soil temperature under all conditions. The CH4 flux resulting from both the control and the addition of N was negatively correlated with porewater SO42- and Cl- concentrations and soil EC in the oligohaline marsh. Overall, N addition significantly increased carbon gas emissions under freshwater conditions while slightly inhibiting carbon gas emissions from the oligohaline marsh. Our findings suggested that even under low salinity conditions, the effects of N loading on CH4 and CO2 emissions from freshwater and oligohaline tidal marshes can vary. We propose that the addition of N to estuarine tidal marshes has a significant effect on the carbon cycle and promotes soil carbon loss, phenomena which may be influenced by salinity.
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Affiliation(s)
- Minjie Hu
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350007, China; College of the Environment and Ecology, Xiamen University, Xiamen 361102, China.
| | - Josep Peñuelas
- CSIC, Global Ecology CREAF-CSIC-UAB, Bellaterra, 08193 Barcelona, Catalonia, Spain; CREAF, Cerdanyola del Vallès, 08193 Barcelona, Catalonia, Spain
| | - Jordi Sardans
- CSIC, Global Ecology CREAF-CSIC-UAB, Bellaterra, 08193 Barcelona, Catalonia, Spain; CREAF, Cerdanyola del Vallès, 08193 Barcelona, Catalonia, Spain
| | - Jiafang Huang
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350007, China
| | - Dongdong Li
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350007, China
| | - Chuan Tong
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350007, China.
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16
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Yang P, Lai DF, Yang H, Tong C. Carbon dioxide dynamics from sediment, sediment-water interface and overlying water in the aquaculture shrimp ponds in subtropical estuaries, southeast China. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 236:224-235. [PMID: 30735941 DOI: 10.1016/j.jenvman.2019.01.088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/02/2019] [Accepted: 01/24/2019] [Indexed: 06/09/2023]
Abstract
Aquaculture ponds can emit a large amount carbon dioxide (CO2), with the consequence of exacerbating global climate change. Many studies about CO2 dynamics across the water-air interface, but CO2 in sediment and overlying water received relative less attention. In this study, CO2 concentration in sediment porewater, the diffusive CO2 fluxes across the sediment-water interface (SWI), and the CO2 production rates in the overlying water (CO2_WP) were determined in the shrimp ponds in the Min River Estuary (MRE) and Jiulong River Estuary (JRE), southeast China, to analyze the dynamics of CO2 among different growth stages of shrimps. Our results showed large variations in porewater CO2 concentrations, CO2 diffusive fluxes and CO2_WP rates among different growth stages, with markedly larger values in the middle stage of shrimp growth. The temporal variation of CO2 in both estuarine ponds followed closely the seasonal change of temperature. The internal CO2 production (CO2_IP) in these ponds was dominated by sediments. A significantly larger mean porewater CO2 concentrations, diffusive fluxes and production rate were observed in the MRE ponds than those in the JRE ponds, which could be attributed to the lower water salinity and a larger source of carbon substrates in the former estuary. Considering a total surface area of 6.63 × 103 km2 across the mariculture ponds in subtropical estuaries, it is estimated conservatively that approximately 100 Gigagram (Gg) of dissolved organic carbon and 190 Gg of dissolved inorganic carbon were transported annually from the mariculture ponds into China's coastal areas. Because of the substantial supply of dissolved carbon, the adjacent coastal waters receiving effluent discharge from the mariculture ponds could become "hotspots" of CO2 emissions. Our results highlight the role of aquaculture pond as a major CO2 source in China's coastal areas, and effective actions are needed to alleviate the greenhouse gas (GHG) emissions from these ponds.
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Affiliation(s)
- Ping Yang
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou, 350007, PR China; School of Geographical Sciences, Fujian Normal University, Fuzhou, 350007, PR China; Research Centre of Wetlands in Subtropical Region, Fujian Normal University, Fuzhou, 350007, PR China.
| | - DerrickY F Lai
- Department of Geography and Resource Management, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Hong Yang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing, 210044, PR China; College of Environmental Science and Engineering, Fujian Normal University, Fuzhou, 350007, PR China; Department of Geography and Environmental Science, University of Reading, Whiteknights, Reading, RG6 6AB, UK
| | - Chuan Tong
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou, 350007, PR China; School of Geographical Sciences, Fujian Normal University, Fuzhou, 350007, PR China; Research Centre of Wetlands in Subtropical Region, Fujian Normal University, Fuzhou, 350007, PR China.
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17
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Assessment of Blue Carbon Storage Loss in Coastal Wetlands under Rapid Reclamation. SUSTAINABILITY 2018. [DOI: 10.3390/su10082818] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Highly productive coastal wetlands play an essential role in storing blue carbon as one of their ecosystem services, but they are increasingly jeopardized by intensive reclamation activities to facilitate rapid population growth and urbanization. Coastal reclamation causes the destruction and severe degradation of wetland ecosystems, which may affect their abilities to store blue carbon. To assist with international accords on blue carbon, we evaluated the dynamics of blue carbon storage in coastal wetlands under coastal reclamation in China. By integrating carbon density data collected from field measurement experiments and from the literature, an InVEST model, Carbon Storage and Sequestration was used to estimate carbon storage across the reclamation area between 1990 and 2015. The result is the first map capable of informing about blue carbon storage in coastal reclamation areas on a national scale. We found that more than 380,000 hectares of coastal wetlands were affected by reclamation, which resulted in the release of ca. 20.7 Tg of blue carbon. The carbon loss from natural wetlands to artificial wetlands accounted for 72.5% of total carbon loss, which highlights the major task in managing coastal sustainability. In addition, the top 20% of coastal wetlands in carbon storage loss covered 4.2% of the total reclamation area, which can be applied as critical information for coastal redline planning. We conclude that the release of blue carbon due to the conversion of natural wetlands exceeded the total carbon emission from energy consumption within the reclamation area. Implementing the Redline policy could guide the management of coastal areas resulting in greater resiliency regarding carbon emission and sustained ecosystem services.
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18
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Zhu L, Qin B, Zhou J, Van Dam B, Shi W. Effects of turbulence on carbon emission in shallow lakes. J Environ Sci (China) 2018; 69:166-172. [PMID: 29941252 DOI: 10.1016/j.jes.2017.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/11/2017] [Accepted: 10/12/2017] [Indexed: 06/08/2023]
Abstract
Turbulent mixing is enhanced in shallow lakes. As a result, exchanges across the air-water and sediment-water interfaces are increased, causing these systems to be large sources of greenhouse gases. This study investigated the effects of turbulence on carbon dioxide (CO2) and methane (CH4) emissions in shallow lakes using simulated mesocosm experiments. Results demonstrated that turbulence increased CO2 emissions, while simultaneously decreasing CH4 emissions by altering microbial processes. Under turbulent conditions, a greater fraction of organic carbon was recycled as CO2 instead of CH4, potentially reducing the net global warming effect because of the lower global warming potential of CO2 relative to CH4. The CH4/CO2 flux ratio was approximately 0.006 under turbulent conditions, but reached 0.078 in the control. The real-time quantitative PCR analysis indicated that methanogen abundance decreased and methanotroph abundance increased under turbulent conditions, inhibiting CH4 production and favoring the oxidation of CH4 to CO2. These findings suggest that turbulence may play an important role in the global carbon cycle by limiting CH4 emissions, thereby reducing the net global warming effect of shallow lakes.
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Affiliation(s)
- Lin Zhu
- Taihu Lake Laboratory Ecosystem Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China.
| | - Boqiang Qin
- Taihu Lake Laboratory Ecosystem Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China.
| | - Jian Zhou
- Taihu Lake Laboratory Ecosystem Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, China
| | - Bryce Van Dam
- Institute of Marine Sciences, University of North Carolina at Chapel Hill, Morehead City, NC, USA
| | - Wenqing Shi
- Center for Eco-Environmental Research, Nanjing Hydraulics Research Institute, Guangzhoulu 223, Nanjing 210029, China
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19
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Gao GF, Li PF, Shen ZJ, Qin YY, Zhang XM, Ghoto K, Zhu XY, Zheng HL. Exotic Spartina alterniflora invasion increases CH 4 while reduces CO 2 emissions from mangrove wetland soils in southeastern China. Sci Rep 2018; 8:9243. [PMID: 29915226 PMCID: PMC6006287 DOI: 10.1038/s41598-018-27625-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 06/04/2018] [Indexed: 11/09/2022] Open
Abstract
Mangroves are critical in global carbon budget while vulnerable to exotic plant invasion. Spartina alterniflora, one of typical salt marsh plant grows forcefully along the coast of China, has invaded the native mangrove habitats in Zhangjiang Estuary. However, the effects of S. alterniflora invasion on soil carbon gases (CH4 and CO2) emission from mangroves are not fully understood. Accordingly, we conducted a field experiment to investigate the soil CH4 and CO2 emission during growing seasons in 2016 and 2017 at four adjacent wetlands, namely bare mudflat (Mud), Kandelia obovata (KO), Avicennia marina (AM) and S. alterniflora (SA). Potential methane production (PMP), potential methane oxidation (PMO), functional microbial abundance and soil biogeochemical properties were measured simultaneously. Our results indicate that S. alterniflora invasion could dramatically increase soil CH4 emissions mainly due to the enhancement in PMP which facilitated by soil EC, MBC, TOC and mcrA gene abundance. Additionally, S. alterniflora invasion decreases soil CO2 emission. Both heterotrophic microbial respiration (16S rRNA) and methane oxidation (pmoA and ANME-pmoA) are responsible for CO2 emission reduction. Furthermore, S. alterniflora invasion greatly increases GWP by stimulating CH4 emissions. Thus, comparing with mangroves, invasive S. alterniflora significantly (p < 0.001) increases CH4 emission while reduces CO2 emission.
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Affiliation(s)
- Gui Feng Gao
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China
| | - Peng Fei Li
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China
| | - Zhi Jun Shen
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China
| | - Ying Ying Qin
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China.,College of Life Sciences, Guangxi Normal University, Gulin, Guangxi, 541004, P. R. China.,Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Gulin, Guangxi, 541004, P. R. China
| | - Xi Min Zhang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China.,Key Laboratory of Plant Physiology and Development Regulation, School of Life Science, Guizhou Normal University, Guiyang, Guizhou, 550001, P. R. China
| | - Kabir Ghoto
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China
| | - Xue Yi Zhu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China
| | - Hai Lei Zheng
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, P. R. China.
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