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Luo J, Wang N, Zhu Y, Wu Z, Ye Z, Christakos G, Wu J. Seasonal effects of fish, seaweed and abalone cultures on dissolved organic matter and carbon sequestration potential in Sansha Bay, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:174144. [PMID: 38901588 DOI: 10.1016/j.scitotenv.2024.174144] [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: 02/28/2024] [Revised: 06/17/2024] [Accepted: 06/17/2024] [Indexed: 06/22/2024]
Abstract
Coastal bays serve as undeniable dissolved organic matter (DOM) reactors and the role of prevalent mariculture in DOM cycling deserves investigation. This study, based on four seasonal field samplings and a laboratory incubation experiment, examined the source and seasonal dynamics of DOM and fluorescent dissolved organic matter (FDOM) in the seawater of fish (Larimichthys crocea, LC), seaweed (Gracilaria lemaneiformis, GL) and abalone (Haliotis sp., HA) culturing zones in Sansha Bay, China. Using three-dimensional fluorescence spectroscopy coupled with parallel factor analysis (EEMs-PARAFAC), three fluorescent components were identified, i.e. protein-like C1, protein-like C2, and humic-like C3. Our results showed that mariculture activities dominated the DOM pool by seasonal generating abundant DOM with lower aromaticity and humification degrees. Accounting for 40-95 % of total fluorescent components, C1 (Ex/Em = 300/340 nm) was regarded the same as D1 (Ex/Em = 300/335 nm) identified in a 180-day degradation experiments of G. lemaneiformis detritus, indicating that the cultured seaweed modulated DOM through the seasonal production of C1. In addition, the incubation experiment revealed that 0.7 % of the total carbon content of seaweed detritus could be preserved as recalcitrant dissolved organic carbon (RDOC). However, fish culture appeared to contribute to liable DOC and protein-like C2, exerting a substantial impact on DOM during winter but making a negligible contribution to carbon sequestration, while abalone culture might promote the potential export and sequestration of seaweed-derived carbon to the ocean. Our results highlight the influences of mariculture activities, especially seaweed culture, in shaping DOM pool in coastal bays. These findings can provide reference for future studies on the carbon accounting of mariculture.
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Affiliation(s)
- Ji Luo
- Ocean College, Zhejiang University, Zhoushan, China
| | - Nan Wang
- Ocean College, Zhejiang University, Zhoushan, China
| | - Yaojia Zhu
- Ocean College, Zhejiang University, Zhoushan, China; Ocean Academy, Zhejiang University, Zhoushan, China
| | - Zhenyu Wu
- Ocean College, Zhejiang University, Zhoushan, China
| | - Zhanjiang Ye
- Ocean College, Zhejiang University, Zhoushan, China
| | | | - Jiaping Wu
- Ocean College, Zhejiang University, Zhoushan, China; Ocean Academy, Zhejiang University, Zhoushan, China.
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2
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Bennett E, Paine ER, Hovenden M, Smith G, Fitzgibbon Q, Hurd CL. Short-term hyposalinity stress increases dissolved organic carbon (DOC) release by the macroalga Sargassum fallax (Ochrophyta). JOURNAL OF PHYCOLOGY 2024. [PMID: 39133164 DOI: 10.1111/jpy.13492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/27/2024] [Accepted: 07/17/2024] [Indexed: 08/13/2024]
Abstract
Dissolved organic carbon (DOC) released by macroalgae supports coastal ocean carbon cycling and contributes to the total oceanic DOC pool. Salinity fluctuates substantially in coastal marine environments due to natural and anthropogenic factors, yet there is limited research on how salinity affects DOC release by ecologically important macroalgae. Here we determined the effect of short-term salinity changes on rates of DOC release by the habitat-forming fucalean seaweed Sargassum fallax (Ochrophyta). Lateral branches (~4 g) cut at the axes of mature individuals were incubated across a salinity gradient (4-46) for 24 h under a 12:12 light:dark cycle, and seawater was sampled for DOC at 0, 12, and 24 h. Physiological assays (tissue water content, net photosynthesis, respiration, tissue carbon, and nitrogen content) were undertaken at the end of the 24-h experiment. Dissolved organic carbon release increased with decreasing salinity while net photosynthesis decreased. Dissolved organic carbon release rates at the lowest salinity tested (4) were ~3.3 times greater in the light than in the dark, indicating two potential DOC release mechanisms: light-mediated active exudation and passive release linked to osmotic stress. Tissue water content decreased with increasing salinity. These results demonstrate that hyposalinity stress alters the osmotic status of S. fallax, reducing photosynthesis and increasing DOC release. This has important implications for understanding how salinity conditions encountered by macroalgae may affect their contribution to the coastal ocean carbon cycle.
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Affiliation(s)
- Eloise Bennett
- Institute for Marine and Antarctic Studies, University of Tasmania (UTAS), Hobart, Tasmania, Australia
| | - Ellie R Paine
- Institute for Marine and Antarctic Studies, University of Tasmania (UTAS), Hobart, Tasmania, Australia
| | - Mark Hovenden
- School of Natural Sciences, University of Tasmania (UTAS), Hobart, Tasmania, Australia
| | - Gregory Smith
- Institute for Marine and Antarctic Studies, University of Tasmania (UTAS), Hobart, Tasmania, Australia
| | - Quinn Fitzgibbon
- Institute for Marine and Antarctic Studies, University of Tasmania (UTAS), Hobart, Tasmania, Australia
| | - Catriona L Hurd
- Institute for Marine and Antarctic Studies, University of Tasmania (UTAS), Hobart, Tasmania, Australia
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3
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Carlson AK, Yoshimura T, Kudo I. Kelp dissolved organic carbon release is seasonal and annually enhanced during senescence. JOURNAL OF PHYCOLOGY 2024. [PMID: 39031293 DOI: 10.1111/jpy.13483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 05/27/2024] [Accepted: 06/12/2024] [Indexed: 07/22/2024]
Abstract
Macroalgae influence local and global biogeochemical cycles through their production of dissolved organic carbon (DOC). Yet, data remain scarce and annualized estimates are typically based on high growth periods without considering seasonal variability. Although the mechanisms of active exudation and passive leakage need clarifying, ecophysiological stress is known to enhance DOC release. Therefore, DOC leakage from seasonally senescent macroalgae may be overlooked. This study focuses on the annual kelp Saccharina japonica var. religiosa (class Phaeophyceae) from Oshoro Bay, Hokkaido, Japan. Three years (2020-2022) of seasonal data were collected and analyzed, with least squares mean DOC release rates established for kelp (n = 88) across 16 incubation experiments (t ≥ 4 d, DOC samples ≥1 · d-1) under different photosynthetically active radiation (PAR) treatments (200, 400, 1200, or 1500 μmol photons · m-2 · s-1). Differences in PAR, dry weight biomass (g DW), sea surface temperature, or salinity could not explain DOC release-rate variability, which was high between individual kelp. Instead, there were significant intra-annual differences, with mean DOC release rates (mg C · g-1 DW · d-1 ± standard error between n kelp) higher during the autumn "late decay" period (0.71 ± 0.10, n = 27) compared to the winter "early growth" period (0.14 ± 0.025, n = 10) and summer "early decay" period (0.25 ± 0.050, n = 24). This relationship between seasonal senescence and macroalgal DOC release is further evidence that long-term, place-based studies of DOC dynamics are essential and that global extrapolations are premature.
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Affiliation(s)
- Andrew Kalani Carlson
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Takeshi Yoshimura
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, Japan
| | - Isao Kudo
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, Japan
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4
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Annamalai J, Seetharaman B, Sellamuthu I. Nanomaterials in the environment and their pragmatic voyage at various trophic levels in an ecosystem. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 364:121307. [PMID: 38870799 DOI: 10.1016/j.jenvman.2024.121307] [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: 01/04/2024] [Revised: 04/30/2024] [Accepted: 05/30/2024] [Indexed: 06/15/2024]
Abstract
In the development of nanotechnology, nanomaterials (NMs) have a huge credential in advancing the existing follow-ups of analytical and diagnosis techniques, drug designing, agricultural science, electronics, cosmetics, sports, textiles and water purification. However, NMs have also grasped attention of researchers onto their toxicity. In the present review, initially the development of notable NMs such as metal and metal-oxide nanoparticles (NPs), magnetic NPs, carbon-based NMs and quantum dots intended to be commercialized along with their applications are discussed. This is followed by the current scenario of NMs in the environment to widen the outlook on the concentration of NPs in the environmental compartments and the frequency of organism exposed to NPs at varied trophic levels. In order to understand the physiochemical and morphological significance of NPs in exhibiting toxicity, fate of NPs in the environment is briefly deliberated. This is further geared-up to glance in-sightedly on the organisms starting from primary producer to primary consumer, secondary consumer, tertiary consumer and decomposers encountering NPs in their habitual niche. The state of NPs to which organisms are exposed, mechanism of NP uptake and toxicity, anomalies faced at each trophic level, concentration of NPs that is liable to cause toxicity and, biotransfer of NPs to the next generation and trophic level are detailed. Finally, the future prospects on bioaccumulation and biomagnification of NP-based products are conversed. Thus, the review would be noteworthy in unveiling the significance of NPs in forthcoming years combined with threat towards each organism in an ecosystem.
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Affiliation(s)
- Jayshree Annamalai
- Endocrine Disruption and Reproductive Toxicology (EDART) Laboratory, Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, India.
| | - Barathi Seetharaman
- Endocrine Disruption and Reproductive Toxicology (EDART) Laboratory, Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, India.
| | - Iyappan Sellamuthu
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, India.
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Younker IT, Molnar N, Scorza K, Weed R, Light SH, Pfister CA. Bacteria on the foundational kelp in kelp forest ecosystems: Insights from culturing, whole genome sequencing and metabolic assays. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13270. [PMID: 38778582 PMCID: PMC11112141 DOI: 10.1111/1758-2229.13270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 04/06/2024] [Indexed: 05/25/2024]
Abstract
In coastal marine ecosystems, kelp forests serve as a vital habitat for numerous species and significantly influence local nutrient cycles. Bull kelp, or Nereocystis luetkeana, is a foundational species in the iconic kelp forests of the northeast Pacific Ocean and harbours a complex microbial community with potential implications for kelp health. Here, we report the isolation and functional characterisation of 16 Nereocystis-associated bacterial species, comprising 13 Gammaproteobacteria, 2 Flavobacteriia and 1 Actinomycetia. Genome analyses of these isolates highlight metabolisms potentially beneficial to the host, such as B vitamin synthesis and nitrogen retention. Assays revealed that kelp-associated bacteria thrive on amino acids found in high concentrations in the ocean and in the kelp (glutamine and asparagine), generating ammonium that may facilitate host nitrogen acquisition. Multiple isolates have genes indicative of interactions with key elemental cycles in the ocean, including carbon, nitrogen and sulphur. We thus report a collection of kelp-associated microbial isolates that provide functional insight for the future study of kelp-microbe interactions.
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Affiliation(s)
- Isaac T. Younker
- Committee on MicrobiologyThe University of ChicagoChicagoIllinoisUSA
| | - Nichos Molnar
- The CollegeThe University of ChicagoChicagoIllinoisUSA
| | - Kaylie Scorza
- The CollegeThe University of ChicagoChicagoIllinoisUSA
| | - Roo Weed
- The Graduate Program in Biophysical SciencesThe University of ChicagoChicagoIllinoisUSA
| | - Samuel H. Light
- Department of MicrobiologyThe University of ChicagoChicagoIllinoisUSA
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6
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Xie Y, Su J, Shao K, Hu T, Ming H, Shi T, Wang W, Fan J. Long-term response of the microbial community to the degradation of DOC released from Undaria pinnatifida. MARINE ENVIRONMENTAL RESEARCH 2024; 194:106313. [PMID: 38211474 DOI: 10.1016/j.marenvres.2023.106313] [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: 09/19/2023] [Revised: 12/05/2023] [Accepted: 12/18/2023] [Indexed: 01/13/2024]
Abstract
With the aim to study the mechanism underlying the macroalgal carbon sequestration driven by microbes, we investigated the microbial community using metagenomics methods and its long-term degradation of dissolved organic carbon (DOC) derived from Undaria pinnatifida. It was observed that after removing U. pinnatifida, the concentration of the DOC decreased significantly (p < 0.05) within 4 days. Over a period of 120 days of degradation, the concentration of remaining DOC (26%) remained stable. The succession of microbial community corresponded to the three stages of DOC concentration variation. Moreover, the structure of microbes community and its metabolic function exhibited evident patterns of succession. The concentration of DOC was correlated negatively with the abundances of Planctomycetaceae (p < 0.01), and was correlated positively with the abundances of Roseobacteraceae and Rhodobacteraceae (p < 0.01). In addition, the metabolic pathways related to "Glycolysis/Gluconeogenesis", "Alanine, aspartate, and glutamate metabolism", "Citrate cycle (TCA cycle)" and "Tryptophan metabolism" was significantly correlated with the variations in DOC concentration (p < 0.05). These findings indicate that the variation in the DOC concentration was closely linked to the succession of Planctomycetaceae, Roseobacteraceae, Rhodobacteraceae, and the degradation of DOC derived from U. pinnatifida appeared to be influenced by metabolic functions.
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Affiliation(s)
- Yuyang Xie
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Jie Su
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China
| | - Kuishuang Shao
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China
| | - Tian Hu
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian, 116023, Liaoning, China
| | - Hongxia Ming
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China
| | - Tingting Shi
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China
| | - Wenjing Wang
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian, 116023, Liaoning, China
| | - Jingfeng Fan
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China; State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, 116023, Liaoning, China.
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7
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Hurd CL, Gattuso JP, Boyd PW. Air-sea carbon dioxide equilibrium: Will it be possible to use seaweeds for carbon removal offsets? JOURNAL OF PHYCOLOGY 2024; 60:4-14. [PMID: 37943584 DOI: 10.1111/jpy.13405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 11/10/2023]
Abstract
To limit global warming below 2°C by 2100, we must drastically reduce greenhouse gas emissions and additionally remove ~100-900 Gt CO2 from the atmosphere (carbon dioxide removal, CDR) to compensate for unavoidable emissions. Seaweeds (marine macroalgae) naturally grow in coastal regions worldwide where they are crucial for primary production and carbon cycling. They are being considered as a biological method for CDR and for use in carbon trading schemes as offsets. To use seaweeds in carbon trading schemes requires verification that seaweed photosynthesis that fixes CO2 into organic carbon results in CDR, along with the safe and secure storage of the carbon removed from the atmosphere for more than 100 years (sequestration). There is much ongoing research into the magnitude of seaweed carbon storage pools (e.g., as living biomass and as particulate and dissolved organic carbon in sediments and the deep ocean), but these pools do not equate to CDR unless the amount of CO2 removed from the atmosphere as a result of seaweed primary production can be quantified and verified. The draw-down of atmospheric CO2 into seawater is via air-sea CO2 equilibrium, which operates on time scales of weeks to years depending upon the ecosystem considered. Here, we explain why quantifying air-sea CO2 equilibrium and linking this process to seaweed carbon storage pools is the critical step needed to verify CDR by discrete seaweed beds and nearshore and open ocean aquaculture systems prior to their use in carbon trading.
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Affiliation(s)
- C L Hurd
- Institute of Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - J-P Gattuso
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-Mer, France
- Institute for Sustainable Development and International Relations, Paris, France
| | - P W Boyd
- Institute of Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
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8
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Yu XA, McLean C, Hehemann JH, Angeles-Albores D, Wu F, Muszyński A, Corzett CH, Azadi P, Kujawinski EB, Alm EJ, Polz MF. Low-level resource partitioning supports coexistence among functionally redundant bacteria during successional dynamics. THE ISME JOURNAL 2024; 18:wrad013. [PMID: 38365244 PMCID: PMC10811730 DOI: 10.1093/ismejo/wrad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/09/2023] [Accepted: 12/05/2023] [Indexed: 02/18/2024]
Abstract
Members of microbial communities can substantially overlap in substrate use. However, what enables functionally redundant microorganisms to coassemble or even stably coexist remains poorly understood. Here, we show that during unstable successional dynamics on complex, natural organic matter, functionally redundant bacteria can coexist by partitioning low-concentration substrates even though they compete for one simple, dominant substrate. We allowed ocean microbial communities to self-assemble on leachates of the brown seaweed Fucus vesiculosus and then analyzed the competition among 10 taxonomically diverse isolates representing two distinct stages of the succession. All, but two isolates, exhibited an average of 90% ± 6% pairwise overlap in resource use, and functional redundancy of isolates from the same assembly stage was higher than that from between assembly stages, leading us to construct a simpler four-isolate community with two isolates from each of the early and late stages. We found that, although the short-term dynamics of the four-isolate communities in F. vesiculosus leachate was dependent on initial isolate ratios, in the long term, the four isolates stably coexist in F. vesiculosus leachate, albeit with some strains at low abundance. We therefore explored the potential for nonredundant substrate use by genomic content analysis and RNA expression patterns. This analysis revealed that the four isolates mainly differed in peripheral metabolic pathways, such as the ability to degrade pyrimidine, leucine, and tyrosine, as well as aromatic substrates. These results highlight the importance of fine-scale differences in metabolic strategies for supporting the frequently observed coexistence of large numbers of rare organisms in natural microbiomes.
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Affiliation(s)
- Xiaoqian Annie Yu
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
- Division of Microbial Ecology, Department of Microbiology and Ecosystems Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna 1030, Austria
| | - Craig McLean
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
- MIT/WHOI Joint Program in Oceanography/Applied Ocean Science and Engineering, Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
| | - Jan-Hendrik Hehemann
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - David Angeles-Albores
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Fuqing Wu
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Artur Muszyński
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, United States
| | - Christopher H Corzett
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, United States
| | - Elizabeth B Kujawinski
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
| | - Eric J Alm
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
- Broad Institute of MIT and Harvard, Cambridge, MA 02139, United States
- Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Martin F Polz
- Division of Microbial Ecology, Department of Microbiology and Ecosystems Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna 1030, Austria
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
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9
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Li H, Feng X, Xiong T, Shao W, Wu W, Zhang Y. Particulate Organic Carbon Released during Macroalgal Growth Has Significant Carbon Sequestration Potential in the Ocean. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:19723-19731. [PMID: 37963337 DOI: 10.1021/acs.est.3c04959] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Substantial amounts of particulate organic carbon (POC) are released during macroalgal growth; however, the fate of these POCs and their carbon sequestration effects remain unclear. Here, field investigations found that Ulva prolifera caused a significant increase of POC in seawater below the surface during a macroalgal bloom. However, laboratory simulations revealed that 77.6% of these POC was easily degraded by microorganisms in a short period of time, concurrently resulting in the production of dissolved organic carbon (DOC) from POC transformation. Over a period of 3 months, the bioavailable components of macroalgae-released POC and POC-transformed DOC were degraded, leaving 39.6% of the antibiodegradable substances composed of biorecalcitrant POC and biorecalcitrant DOC. However, although the biorecalcitrant POC was rich in humic-like components resisting biodegradation, the biorecalcitrant POC exhibited greater sensitivity to photodegradation than biorecalcitrant DOC. The photodegradation removal rate of biorecalcitrant POC (14.1%) was more than 10 times that of biorecalcitrant DOC (1.2%). Ultimately, a substantial portion (36.3%) of the POC released by growing macroalgae could potentially perform long-term carbon sequestration after conversion to recalcitrant POC and recalcitrant DOC, and these inert carbons derived from macroalgal POC have been previously ignored and should also be included in macroalgal carbon sequestration accounting.
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Affiliation(s)
- Hongmei Li
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Qingdao New Energy Shandong Laboratory, Qingdao 266101, China
| | - Xiuting Feng
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianqi Xiong
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Wei Shao
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Wangchi Wu
- Qingdao Municipal Bureau of Ecology and Environment, Qingdao 266003, China
| | - Yongyu Zhang
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Qingdao New Energy Shandong Laboratory, Qingdao 266101, China
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10
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Pessarrodona A, Franco-Santos RM, Wright LS, Vanderklift MA, Howard J, Pidgeon E, Wernberg T, Filbee-Dexter K. Carbon sequestration and climate change mitigation using macroalgae: a state of knowledge review. Biol Rev Camb Philos Soc 2023; 98:1945-1971. [PMID: 37437379 DOI: 10.1111/brv.12990] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 07/14/2023]
Abstract
The conservation, restoration, and improved management of terrestrial forests significantly contributes to mitigate climate change and its impacts, as well as providing numerous co-benefits. The pressing need to reduce emissions and increase carbon removal from the atmosphere is now also leading to the development of natural climate solutions in the ocean. Interest in the carbon sequestration potential of underwater macroalgal forests is growing rapidly among policy, conservation, and corporate sectors. Yet, our understanding of whether carbon sequestration from macroalgal forests can lead to tangible climate change mitigation remains severely limited, hampering their inclusion in international policy or carbon finance frameworks. Here, we examine the results of over 180 publications to synthesise evidence regarding macroalgal forest carbon sequestration potential. We show that research efforts on macroalgae carbon sequestration are heavily skewed towards particulate organic carbon (POC) pathways (77% of data publications), and that carbon fixation is the most studied flux (55%). Fluxes leading directly to carbon sequestration (e.g. carbon export or burial in marine sediments) remain poorly resolved, likely hindering regional or country-level assessments of carbon sequestration potential, which are only available from 17 of the 150 countries where macroalgal forests occur. To solve this issue, we present a framework to categorize coastlines according to their carbon sequestration potential. Finally, we review the multiple avenues through which this sequestration can translate into climate change mitigation capacity, which largely depends on whether management interventions can increase carbon removal above a natural baseline or avoid further carbon emissions. We find that conservation, restoration and afforestation interventions on macroalgal forests can potentially lead to carbon removal in the order of 10's of Tg C globally. Although this is lower than current estimates of natural sequestration value of all macroalgal habitats (61-268 Tg C year-1 ), it suggests that macroalgal forests could add to the total mitigation potential of coastal blue carbon ecosystems, and offer valuable mitigation opportunities in polar and temperate areas where blue carbon mitigation is currently low. Operationalizing that potential will necessitate the development of models that reliably estimate the proportion of production sequestered, improvements in macroalgae carbon fingerprinting techniques, and a rethinking of carbon accounting methodologies. The ocean provides major opportunities to mitigate and adapt to climate change, and the largest coastal vegetated habitat on Earth should not be ignored simply because it does not fit into existing frameworks.
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Affiliation(s)
- Albert Pessarrodona
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, 6009, Western Australia, Australia
- Conservation International, 2011 Crystal Dr., Suite 600, Arlington, VA, USA
- International Blue Carbon Institute, 42B Boat Quay, Singapore, 049831, Singapore
| | - Rita M Franco-Santos
- CSIRO Environment, Indian Ocean Marine Research Centre, Crawley, 6009, Western Australia, Australia
| | - Luka Seamus Wright
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, 6009, Western Australia, Australia
- CSIRO Environment, Indian Ocean Marine Research Centre, Crawley, 6009, Western Australia, Australia
| | - Mathew A Vanderklift
- CSIRO Environment, Indian Ocean Marine Research Centre, Crawley, 6009, Western Australia, Australia
| | - Jennifer Howard
- Conservation International, 2011 Crystal Dr., Suite 600, Arlington, VA, USA
- International Blue Carbon Institute, 42B Boat Quay, Singapore, 049831, Singapore
| | - Emily Pidgeon
- Conservation International, 2011 Crystal Dr., Suite 600, Arlington, VA, USA
- International Blue Carbon Institute, 42B Boat Quay, Singapore, 049831, Singapore
| | - Thomas Wernberg
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, 6009, Western Australia, Australia
- Institute of Marine Research, Nye Flødevigveien 20, His, 4817, Norway
| | - Karen Filbee-Dexter
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, 6009, Western Australia, Australia
- Institute of Marine Research, Nye Flødevigveien 20, His, 4817, Norway
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11
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Kosek K, Kukliński P. Impact of kelp forest on seawater chemistry - A review. MARINE POLLUTION BULLETIN 2023; 196:115655. [PMID: 37839130 DOI: 10.1016/j.marpolbul.2023.115655] [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: 07/26/2023] [Revised: 09/18/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023]
Abstract
Kelp forests, globally distributed in cool temperate and polar waters, are renowned for their pivotal role in supporting species diversity and fostering macroalgae productivity. These high-canopy algal ecosystems dynamically influence their surroundings, particularly by altering the physicochemical properties of seawater. This review article aims to underscore the significance of kelp forests in modifying water masses. By serving as effective carbon sinks through the absorption of bicarbonate (HCO3-) and carbon dioxide (CO2) for photosynthesis, kelp forests mitigate nearby acidity levels while enhancing dissolved oxygen concentrations, essential for sustaining diverse marine communities. Additionally, kelp beds have exhibited the need to use inorganic ions (NO3-, NO2-, PO43-) from seawater in order to grow, albeit with associated increases in NH4+ concentrations. Specific examples and findings from relevant studies will be presented to illustrate the profound impact of kelp forests on seawater chemistry, emphasizing their vital role in marine ecosystems.
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Affiliation(s)
- Klaudia Kosek
- Marine Ecology Department, Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland.
| | - Piotr Kukliński
- Marine Ecology Department, Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland
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12
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Paine ER, Brewer EA, Schmid M, Diaz-Pulido G, Boyd PW, Hurd CL. Strong seasonal patterns of DOC release by a temperate seaweed community: Implications for the coastal ocean carbon cycle. JOURNAL OF PHYCOLOGY 2023; 59:738-750. [PMID: 37252690 DOI: 10.1111/jpy.13352] [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: 11/14/2022] [Revised: 02/14/2023] [Accepted: 04/23/2023] [Indexed: 05/31/2023]
Abstract
Release of dissolved organic carbon (DOC) by seaweed underpins the microbial food web and is crucial for the coastal ocean carbon cycle. However, we know relatively little of seasonal DOC release patterns in temperate regions of the southern hemisphere. Strong seasonal changes in inorganic nitrogen availability, irradiance, and temperature regulate the growth of seaweeds on temperate reefs and influence DOC release. We seasonally surveyed and sampled seaweed at Coal Point, Tasmania, over 1 year. Dominant species with or without carbon dioxide (CO2 ) concentrating mechanisms (CCMs) were collected for laboratory experiments to determine seasonal rates of DOC release. During spring and summer, substantial DOC release (10.06-33.54 μmol C · g DW-1 · h-1 ) was observed for all species, between 3 and 27 times greater than during autumn and winter. Our results suggest that inorganic carbon (Ci ) uptake strategy does not regulate DOC release. Seasonal patterns of DOC release were likely a result of photosynthetic overflow during periods of high gross photosynthesis indicated by variations in tissue C:N ratios. For each season, we calculated a reef-scale net DOC release for seaweed at Coal Point of 7.84-12.9 g C · m-2 · d-1 in spring and summer, which was ~16 times greater than in autumn and winter (0.2-1.0 g C · m-2 · d-1 ). Phyllospora comosa, which dominated the biomass, contributed the most DOC to the coastal ocean, up to ~14 times more than Ecklonia radiata and the understory assemblage combined. Reef-scale DOC release was driven by seasonal changes in seaweed physiology rather than seaweed biomass.
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Affiliation(s)
- Ellie R Paine
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Elizabeth A Brewer
- CSIRO Oceans and Atmosphere, Castray Esplanade, Hobart, Tasmania, Australia
| | - Matthias Schmid
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
- Trinity College Dublin, Dublin, Ireland
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Guillermo Diaz-Pulido
- School of Environment and Science, Coastal Marine Research Centre, and Australian Rivers Institute-Coast and Estuaries, Nathan Campus, Griffith University, Brisbane, Queensland, Australia
| | - Philip W Boyd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Catriona L Hurd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
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13
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Paine ER, Boyd PW, Strzepek RF, Ellwood M, Brewer EA, Diaz-Pulido G, Schmid M, Hurd CL. Iron limitation of kelp growth may prevent ocean afforestation. Commun Biol 2023; 6:607. [PMID: 37280329 PMCID: PMC10244339 DOI: 10.1038/s42003-023-04962-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 05/22/2023] [Indexed: 06/08/2023] Open
Abstract
Carbon dioxide removal (CDR) and emissions reduction are essential to alleviate climate change. Ocean macroalgal afforestation (OMA) is a CDR method already undergoing field trials where nearshore kelps, on rafts, are purposefully grown offshore at scale. Dissolved iron (dFe) supply often limits oceanic phytoplankton growth, however this potentially rate-limiting factor is being overlooked in OMA discussions. Here, we determine the limiting dFe concentrations for growth and key physiological functions of a representative kelp species, Macrocystis pyrifera, considered as a promising candidate for OMA. dFe additions to oceanic seawater ranging 0.01-20.2 nM Fe' ‒ Fe' being the sum of dissolved inorganic Fe(III) species ‒ result in impaired physiological functions and kelp mortality. Kelp growth cannot be sustained at oceanic dFe concentrations, which are 1000-fold lower than required by M. pyrifera. OMA may require additional perturbation of offshore waters via dFe fertilisation.
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Affiliation(s)
- Ellie R Paine
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia.
| | - Philip W Boyd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia
| | - Robert F Strzepek
- Australian Antarctic Program Partnership (AAPP), Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
| | - Michael Ellwood
- Research School of Earth Sciences, The Australian National University, Canberra, ACT, 0200, Australia
| | - Elizabeth A Brewer
- CSIRO Oceans and Atmosphere, Castray Esplanade, Hobart, TAS, 7001, Australia
| | - Guillermo Diaz-Pulido
- School of Environment and Science, Coastal and Marine Research Centre, and Australian Rivers Institute-Coast and Estuaries, Nathan Campus, Griffith University, Brisbane, QLD, 4111, Australia
| | - Matthias Schmid
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia
- Trinity College Dublin, University of Dublin, Dublin, Ireland
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Catriona L Hurd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia
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14
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Wear B, O'Connor NE, Schmid MJ, Jackson MC. What does the future look like for kelp when facing multiple stressors? Ecol Evol 2023; 13:e10203. [PMID: 37384243 PMCID: PMC10293785 DOI: 10.1002/ece3.10203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 06/30/2023] Open
Abstract
As primary producers and ecosystem engineers, kelp (generally Order Laminariales) are ecologically important, and their decline could have far-reaching consequences. Kelp are valuable in forming habitats for fish and invertebrates and are crucial for adaptation to climate change by creating coastal defenses and in providing key functions, such as carbon sequestration and food provision. Kelp are threatened by multiple stressors, such as climate change, over-harvesting of predators, and pollution. In this opinion paper, we discuss how these stressors may interact to affect kelp, and how this varies under different contexts. We argue that more research that bridges kelp conservation and multiple stressor theory is needed and outline key questions that should be addressed as a priority. For instance, it is important to understand how previous exposure (either to earlier generations or life stages) determines responses to emerging stressors, and how responses in kelp scale up to alter food webs and ecosystem functioning. By increasing the temporal and biological complexity of kelp research in this way, we will improve our understanding allowing better predictions. This research is essential for the effective conservation and potential restoration of kelp in our rapidly changing world.
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Affiliation(s)
- Brigitte Wear
- Department of BiologyUniversity of OxfordOxfordUK
- Somerville CollegeOxfordUK
| | - Nessa E. O'Connor
- School of Natural Sciences, Discipline of ZoologyTrinity College DublinDublinIreland
| | - Matthias J. Schmid
- School of Natural Sciences, Discipline of ZoologyTrinity College DublinDublinIreland
- School of Natural ScienceUniversity of GalwayGalwayIreland
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15
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Li H, Feng X, Xiong T, He C, Wu W, Shi Q, Jiao N, Zhang Y. Green Tides Significantly Alter the Molecular Composition and Properties of Coastal DOC and Perform Dissolved Carbon Sequestration. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:770-779. [PMID: 36511764 DOI: 10.1021/acs.est.2c05684] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Despite green tides (or macroalgal blooms) having multiple negative effects, it is thought that they have a positive effect on carbon sequestration, although this aspect is rarely studied. Here, during the world's largest green tide (caused by Ulva prolifera) in the Yellow Sea, the concentration of dissolved organic carbon (DOC) increased by 20-37% in intensive macroalgal areas, and thousands of new molecular formulas rich in CHNO and CHOS were introduced. The DOC molecular species derived from U. prolifera constituted ∼18% of the total DOC molecular species in the seawater of bloom area, indicating the profound effect that green tides have on shaping coastal DOC. In addition, 46% of the macroalgae-derived DOC was labile DOC (LDOC), which had only a short residence time due to rapid microbial utilization. The remaining 54% was recalcitrant DOC (RDOC) rich in humic-like substances, polycyclic aromatics, and highly aromatic compounds that resisted microbial degradation and therefore have the potential to play a role in long-term carbon sequestration. Notably, source analysis showed that in addition to the microbial carbon pump, macroalgae are also an important source of RDOC. The number of RDOC molecular species contributed by macroalgae even exceed (77 vs 23%) that contributed by microorganisms.
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Affiliation(s)
- Hongmei Li
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiuting Feng
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianqi Xiong
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Wangchi Wu
- Qingdao Municipal Bureau of Ecology and Environment, Qingdao 266003, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Nianzhi Jiao
- Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361100, China
| | - Yongyu Zhang
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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16
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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. JOURNAL OF PHYCOLOGY 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] [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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17
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Saravanan A, Deivayanai VC, Senthil Kumar P, Rangasamy G, Varjani S. CO 2 bio-mitigation using genetically modified algae and biofuel production towards a carbon net-zero society. BIORESOURCE TECHNOLOGY 2022; 363:127982. [PMID: 36126842 DOI: 10.1016/j.biortech.2022.127982] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/10/2022] [Accepted: 09/12/2022] [Indexed: 06/15/2023]
Abstract
CO2 sequestration carried by biological methodologies shows enhanced potential and has the advantage that biomass produced from the captured CO2 can be used for different applications. Bio-mitigation of carbons through a micro-algal system addresses a promising and feasible option. This review mostly focused on the role of algae, particular mechanisms, bioreactors in algae cultivation, and genetically modified algae in CO2 fixation and energy generation systems. A combination of CO2 bio-mitigation and biofuel production might deliver an extremely promising alternative to current CO2 mitigation systems. Bio mitigation in which the excess carbon is captured and bio fixation which the carbon is captured by algae or autotrophs and used for producing biofuel. This review revealed that steps for biofuel production from algae include factors affecting, harvesting techniques, oil extraction and transesterification. This review helps environmentalists and researchers to assess the effect of algae-based biorefinery on the green environment.
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Affiliation(s)
- A Saravanan
- Department of Sustainable Engineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai 602105, India
| | - V C Deivayanai
- Department of Sustainable Engineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai 602105, India
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai 603110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Chennai 603110, India.
| | - Gayathri Rangasamy
- University Centre for Research and Development & Department of Civil Engineering, Chandigarh University, Gharuan, Mohali, Punjab 140413, India
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar 382 010, Gujarat, India
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18
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Lai Q, Ma J, He F, Zhang A, Pei D, Yu M. Current and Future Potential of Shellfish and Algae Mariculture Carbon Sinks in China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148873. [PMID: 35886723 PMCID: PMC9322719 DOI: 10.3390/ijerph19148873] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/28/2022] [Accepted: 07/18/2022] [Indexed: 11/29/2022]
Abstract
Shellfish and algae mariculture make up an important part of the marine fishery carbon sink. Carbon sink research is necessary to ensure China achieves its goal of carbon neutrality. This study used the material quality assessment method to estimate the carbon sink capacity of shellfish and algae. Product value, carbon storage value, and oxygen release value were used to calculate the economic value of shellfish and algae carbon sequestration. The results showed that the annual average shellfish and algae carbon sink in China was 1.10 million tons from 2003 to 2019, of which shellfish accounted for 91.63%, wherein Crassostreagigas, Ruditapesphilippinarum, and Chlamysfarreri were the main contributors. The annual average economic value of China’s shellfish and algae carbon sequestration was USD 71,303.56 million, and the product value was the main contributor, accounting for 99.11%. The carbon sink conversion ratios of shellfish and algae were 8.37% and 5.20%, respectively, thus making shellfish the aquaculture species with the strongest carbon sink capacity and the greatest carbon sink potential. The estimated growth rate in the shellfish and algae removable carbon sink was 33,900 tons/year in China, but this trend was uncertain. The capacity for carbon sequestration and exchange by aquaculture can be improved by expanding breeding space, promoting multi-level comprehensive breeding modes, and marine artificial upwelling projects.
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Affiliation(s)
- Qiuying Lai
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; (Q.L.); (J.M.); (A.Z.)
| | - Jie Ma
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; (Q.L.); (J.M.); (A.Z.)
| | - Fei He
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; (Q.L.); (J.M.); (A.Z.)
- Correspondence:
| | - Aiguo Zhang
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; (Q.L.); (J.M.); (A.Z.)
| | - Dongyan Pei
- School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China;
| | - Minghui Yu
- College of Environment, Hohai University, Nanjing 210024, China;
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19
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Lozada M, Zabala MS, García PE, Diéguez MC, Bigatti G, Fermani P, Unrein F, Dionisi HM. Microbial assemblages associated with the invasive kelp Undaria pinnatifida in Patagonian coastal waters: Structure and alginolytic potential. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 830:154629. [PMID: 35337861 DOI: 10.1016/j.scitotenv.2022.154629] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/12/2022] [Accepted: 03/13/2022] [Indexed: 06/14/2023]
Abstract
Undaria pinnatifida is a brown algae native to Asia that has settled in various regions worldwide, periodically contributing with large quantities of C and nutrients during its annual cycle. In this work, we analyzed a coastal site in Patagonia (Argentina) that has been colonized for three decades by U. pinnatifida, focusing on associated microbial communities in three different compartments. An important influence of algae was observed in seawater, especially in the bottom of the algal forest during the austral summer (January) at the moment of greater biomass release. This was evidenced by changes in DOC concentration and its quality indicators (higher Freshness and lower Humification index) and higher DIC. Although maximum values of NH4 and PO4 were observed in January, bottom water samples had lower concentrations than surface water, suggesting nutrient consumption by bacteria during algal DOM release. Concomitantly, bacterial abundance peaked, reaching 4.68 ± 1.33 × 105 cells mL -1 (January), showing also higher capability of degrading alginate, a major component of brown algae cell walls. Microbial community structure was influenced by sampling date, season, sampling zone (surface or bottom), and environmental factors (temperature, salinity, pH, dissolved oxygen, nutrients). Samples of epiphytic biofilms showed a distinct community structure compared to seawater, lower diversity, and remarkably high alginolytic capability, suggesting adaptation to degrade algal biomass. A high microdiversity of populations of the genus Leucothrix (Gammaproteobacteria, Thiotrichales) that accounted for a large fraction of epiphytic communities was observed, and changed over time. Epiphytic assemblages shared more taxa with bottom than with surface seawater assemblages, indicating a certain level of exchange between communities in the forest surroundings. This work provides insight into the impact of U. pinnatifida decay on seawater quality, and the role of microbial communities on adapting to massive biomass inputs through rapid DOM turnover.
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Affiliation(s)
- Mariana Lozada
- Laboratorio de Microbiología Ambiental (CESIMAR-CONICET/IBIOMAR-CONICET), Puerto Madryn, Argentina.
| | - María Soledad Zabala
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (IBIOMAR-CONICET), Puerto Madryn, Argentina
| | - Patricia E García
- Grupo de Ecología de Sistemas Acuáticos a Escala de Paisaje (GESAP, INIBIOMA-CONICET-UNComa), Bariloche, Argentina
| | - María C Diéguez
- Grupo de Ecología de Sistemas Acuáticos a Escala de Paisaje (GESAP, INIBIOMA-CONICET-UNComa), Bariloche, Argentina
| | - Gregorio Bigatti
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (IBIOMAR-CONICET), Puerto Madryn, Argentina; Universidad Espíritu Santo, Ecuador
| | - Paulina Fermani
- Laboratorio de Microbiología Ambiental (CESIMAR-CONICET/IBIOMAR-CONICET), Puerto Madryn, Argentina
| | - Fernando Unrein
- Laboratorio de Ecología y Fotobiología Acuática, Instituto Tecnológico de Chascomús (CONICET-UNSAM), Chascomús, Argentina; Escuela de Bio y Nanotecnologías (UNSAM), Argentina
| | - Hebe M Dionisi
- Laboratorio de Microbiología Ambiental (CESIMAR-CONICET/IBIOMAR-CONICET), Puerto Madryn, Argentina
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20
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Li H, Zhang Z, Xiong T, Tang K, He C, Shi Q, Jiao N, Zhang Y. Carbon Sequestration in the Form of Recalcitrant Dissolved Organic Carbon in a Seaweed (Kelp) Farming Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:9112-9122. [PMID: 35686906 DOI: 10.1021/acs.est.2c01535] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Under climate change scenarios, the contribution of macroalgae to carbon sequestration has attracted wide attention. As primary producers, macroalgae can release substantial amounts of dissolved organic carbon (DOC) in seawater. However, little is known about the molecular composition and chemical properties of DOC derived from macroalgae and which of them are recalcitrant DOC (RDOC) that can be sequestered for a long time in the ocean. In the most intensive seaweed (kelp) farming area (Sanggou Bay) in China, we found that kelp mariculture not only significantly increased DOC concentration, but also introduced a variety of new DOC molecular species, many of which were sulfur-containing molecules. A long-term DOC degradation experiment revealed that those DOC with strong resistance to microbial degradation, i.e., RDOC, account for approximately 58% of the DOC extracted from kelp mariculture area. About 85% (3587 out of 4224 with different chemical features) of the RDOC molecular species were steadily present throughout the long-term degradation process. 15% (637 out of 4224 with different chemical features) of the RDOC molecular species were likely newly generated by microorganisms after metabolizing macroalgae-derived labile DOC. All these stable RDOC should be included in the blue carbon budgets of seaweed.
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Affiliation(s)
- Hongmei Li
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Zenghu Zhang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Tianqi Xiong
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Kunxian Tang
- Fujian Provincial Key Laboratory of Marine Ecological Conservation and Restoration, Xiamen 361005, China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Nianzhi Jiao
- Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361100, China
| | - Yongyu Zhang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
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21
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Potential negative effects of ocean afforestation on offshore ecosystems. Nat Ecol Evol 2022; 6:675-683. [PMID: 35449458 DOI: 10.1038/s41559-022-01722-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 03/03/2022] [Indexed: 11/08/2022]
Abstract
Our scientific understanding of climate change makes clear the necessity for both emission reduction and carbon dioxide removal (CDR). The ocean with its large surface area, great depths and long coastlines is central to developing CDR approaches commensurate with the scale needed to limit warming to below 2 °C. Many proposed marine CDR approaches rely on spatial upscaling along with enhancement and/or acceleration of the rates of naturally occurring processes. One such approach is 'ocean afforestation', which involves offshore transport and concurrent growth of nearshore macroalgae (seaweed), followed by their export into the deep ocean. The purposeful occupation for months of open ocean waters by macroalgae, which do not naturally occur there, will probably affect offshore ecosystems through a range of biological threats, including altered ocean chemistry and changed microbial physiology and ecology. Here, we present model simulations of ocean afforestation and link these to lessons from other examples of offshore dispersal, including rafting plastic debris, and discuss the ramifications for offshore ecosystems. We explore what additional metrics are required to assess the ecological implications of this proposed CDR. In our opinion, these ecological metrics must have equal weight to CDR capacity in the development of initial trials, pilot studies and potential licensing.
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Hurd CL, Law CS, Bach LT, Britton D, Hovenden M, Paine ER, Raven JA, Tamsitt V, Boyd PW. Forensic carbon accounting: Assessing the role of seaweeds for carbon sequestration. JOURNAL OF PHYCOLOGY 2022; 58:347-363. [PMID: 35286717 DOI: 10.1111/jpy.13249] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Carbon sequestration is defined as the secure storage of carbon-containing molecules for >100 years, and in the context of carbon dioxide removal for climate mitigation, the origin of this CO2 is from the atmosphere. On land, trees globally sequester substantial amounts of carbon in woody biomass, and an analogous role for seaweeds in ocean carbon sequestration has been suggested. The purposeful expansion of natural seaweed beds and aquaculture systems, including into the open ocean (ocean afforestation), has been proposed as a method of increasing carbon sequestration and use in carbon trading and offset schemes. However, to verify whether CO2 fixed by seaweeds through photosynthesis leads to carbon sequestration is extremely complex in the marine environment compared to terrestrial systems, because of the need to jointly consider: the comparatively rapid turnover of seaweed biomass, tracing the fate of carbon via particulate and dissolved organic carbon pathways in dynamic coastal waters, and the key role of atmosphere-ocean CO2 exchange. We propose a Forensic Carbon Accounting approach, in which a thorough analysis of carbon flows between the atmosphere and ocean, and into and out of seaweeds would be undertaken, for assessing the magnitude of CO2 removal and robust attribution of carbon sequestration to seaweeds.
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Affiliation(s)
- Catriona L Hurd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Cliff S Law
- National Institute of Water and Atmospheric Research, Wellington, 6021, New Zealand
- Department of Marine Science, University of Otago, Dunedin, 9016, New Zealand
| | - Lennart T Bach
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Damon Britton
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Mark Hovenden
- Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Ellie R Paine
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - John A Raven
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Dundee, DD2 5DA, UK
- Climate Change Cluster, University of Technology, Sydney, Ultimo, New South Wales, 2006, Australia
- School of Biological Science, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Veronica Tamsitt
- University of South Florida College of Marine Science, 830 1st St S, St Petersburg, Florida, 33701, USA
- Climate Change Research Centre, University of New South Wales, Sydney, New South Wales, 2052, Australia
| | - Philip W Boyd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7001, Australia
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Xu K, Li M, Wang W, Xu Y, Ji D, Chen C, Xie C. Differences in organic carbon release between conchocelis and thalli of Pyropia haitanensis and responses to changes in light intensity and pH. ALGAL RES 2022. [DOI: 10.1016/j.algal.2021.102574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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