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Yeo JZQ, Rosentreter JA, Oakes JM, Schulz KG, Eyre BD. High carbon dioxide emissions from Australian estuaries driven by geomorphology and climate. Nat Commun 2024; 15:3967. [PMID: 38730255 PMCID: PMC11087516 DOI: 10.1038/s41467-024-48178-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/19/2024] [Indexed: 05/12/2024] Open
Abstract
Estuaries play an important role in connecting the global carbon cycle across the land-to-ocean continuum, but little is known about Australia's contribution to global CO2 emissions. Here we present an Australia-wide assessment, based on CO2 concentrations for 47 estuaries upscaled to 971 assessed Australian estuaries. We estimate total mean (±SE) estuary CO2 emissions of 8.67 ± 0.54 Tg CO2-C yr-1, with tidal systems, lagoons, and small deltas contributing 94.4%, 3.1%, and 2.5%, respectively. Although higher disturbance increased water-air CO2 fluxes, its effect on total Australian estuarine CO2 emissions was small due to the large surface areas of low and moderately disturbed tidal systems. Mean water-air CO2 fluxes from Australian small deltas and tidal systems were higher than from global estuaries because of the dominance of macrotidal subtropical and tropical systems in Australia, which have higher emissions due to lateral inputs. We suggest that global estuarine CO2 emissions should be upscaled based on geomorphology, but should also consider land-use disturbance, and climate.
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Affiliation(s)
- Jacob Z-Q Yeo
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, PO Box 157, East Lismore, NSW, 2480, Australia.
| | - Judith A Rosentreter
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, PO Box 157, East Lismore, NSW, 2480, Australia
| | - Joanne M Oakes
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, PO Box 157, East Lismore, NSW, 2480, Australia
| | - Kai G Schulz
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, PO Box 157, East Lismore, NSW, 2480, Australia
| | - Bradley D Eyre
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, PO Box 157, East Lismore, NSW, 2480, Australia
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Wang F, Liu J, Qin G, Zhang J, Zhou J, Wu J, Zhang L, Thapa P, Sanders CJ, Santos IR, Li X, Lin G, Weng Q, Tang J, Jiao N, Ren H. Coastal blue carbon in China as a nature-based solution toward carbon neutrality. Innovation (N Y) 2023; 4:100481. [PMID: 37636281 PMCID: PMC10451025 DOI: 10.1016/j.xinn.2023.100481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 07/09/2023] [Indexed: 08/29/2023] Open
Abstract
To achieve the Paris Agreement, China pledged to become "Carbon Neutral" by the 2060s. In addition to massive decarbonization, this would require significant changes in ecosystems toward negative CO2 emissions. The ability of coastal blue carbon ecosystems (BCEs), including mangrove, salt marsh, and seagrass meadows, to sequester large amounts of CO2 makes their conservation and restoration an important "nature-based solution (NbS)" for climate adaptation and mitigation. In this review, we examine how BCEs in China can contribute to climate mitigation. On the national scale, the BCEs in China store up to 118 Tg C across a total area of 1,440,377 ha, including over 75% as unvegetated tidal flats. The annual sedimental C burial of these BCEs reaches up to 2.06 Tg C year-1, of which most occurs in salt marshes and tidal flats. The lateral C flux of mangroves and salt marshes contributes to 1.17 Tg C year-1 along the Chinese coastline. Conservation and restoration of BCEs benefit climate change mitigation and provide other ecological services with a value of $32,000 ha-1 year-1. The potential practices and technologies that can be implemented in China to improve BCE C sequestration, including their constraints and feasibility, are also outlined. Future directions are suggested to improve blue carbon estimates on aerial extent, carbon stocks, sequestration, and mitigation potential. Restoring and preserving BCEs would be a cost-effective step to achieve Carbon Neutral by 2060 in China despite various barriers that should be removed.
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Affiliation(s)
- Faming Wang
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
| | - Jihua Liu
- Marine Research Institute, Shandong University, Qingdao 266237, China
| | - Guoming Qin
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfan Zhang
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinge Zhou
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingtao Wu
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
| | - Lulu Zhang
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
| | - Poonam Thapa
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
| | - Christian J. Sanders
- National Marine Science Centre, Faculty of Science and Engineering, Southern Cross University, Coffs Harbour, NSW 2450, Australia
| | - Isaac R. Santos
- Department of Marine Sciences, University of Gothenburg, 41319 Gothenburg, Sweden
| | - Xiuzhen Li
- State Key Laboratory of Estuarine and Coastal Research and Institute of Eco-Chongming, East China Normal University, Shanghai 201100, China
| | - Guanghui Lin
- Key Laboratory for Earth System Modeling, Ministry of Education, Department of Earth System Science, Tsinghua University, Beijing 100084, China
- Laboratory of Stable Isotope and Gulf Ecology, Institute of Ocean Engineering, Tsinghua’s Shenzhen International Graduate School, Shenzhen 518055, China
| | - Qihao Weng
- Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hongkong 999077, China
| | - Jianwu Tang
- State Key Laboratory of Estuarine and Coastal Research and Institute of Eco-Chongming, East China Normal University, Shanghai 201100, China
| | - Nianzhi Jiao
- Innovative Research Center for Carbon Neutralization, Global ONCE Program, Xiamen 361005, China
| | - Hai Ren
- Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510650, China
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Chanda A, Akhand A. Challenges towards the Sustainability and Enhancement of the Indian Sundarban Mangrove's Blue Carbon Stock. Life (Basel) 2023; 13:1787. [PMID: 37629645 PMCID: PMC10455859 DOI: 10.3390/life13081787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/11/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
The Sundarban is the world's largest contiguous mangrove forest and stores around 26.62 Tg of blue carbon. The present study reviewed the factors causing a decline in its blue carbon content and poses a challenge in enhancing the carbon stock of this region. This review emphasized that recurrent tropical cyclones, soil erosion, freshwater scarcity, reduced sediment load into the delta, nutrient deficiency, salt-stress-induced changes in species composition, mangrove clearing, and anthropogenic pollution are the fundamental drivers which can potentially reduce the total blue carbon stock of this region. The southern end of the Ganges-Brahmaputra-Meghna Delta that shelters this forest has stopped its natural progradation due to inadequate sediment flow from the upper reaches. Growing population pressure from the north of the Sundarban Biosphere Reserve and severe erosion in the southern end accentuated by regional sea-level rise has left minimal options to enhance the blue carbon stock by extending the forest premises. This study collated the scholarly observations of the past decades from this region, indicating a carbon sequestration potential deterioration. By collecting the existing knowledge base, this review indicated the aspects that require immediate attention to stop this ecosystem's draining of the valuable carbon sequestered and, at the same time, enhance the carbon stock, if possible. This review provided some key recommendations that can help sustain the blue carbon stock of the Indian Sundarban. This review stressed that characterizing the spatial variability of blue carbon with more sampling points, catering to the damaged trees after tropical cyclones, estuarine rejuvenation in the upper reaches, maintaining species diversity through afforestation programs, arresting coastal erosion through increasing sediment flow, and combating marine pollution have become urgent needs of the hour. The observations synthesized in this study can be helpful for academics, policy managers, and decision makers willing to uphold the sustainability of the blue carbon stock of this crucial ecosystem.
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Affiliation(s)
- Abhra Chanda
- School of Oceanographic Studies, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Anirban Akhand
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- Coastal and Estuarine Environment Research Group, Port and Airport Research Institute, Nagase, Yokosuka 239-0826, Kanagawa, Japan
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Das I, Chanda A, Akhand A, Hazra S. Carbon Biogeochemistry of the Estuaries Adjoining the Indian Sundarbans Mangrove Ecosystem: A Review. Life (Basel) 2023; 13:life13040863. [PMID: 37109391 PMCID: PMC10141991 DOI: 10.3390/life13040863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/09/2023] [Accepted: 03/21/2023] [Indexed: 04/29/2023] Open
Abstract
The present study reviewed the carbon-biogeochemistry-related observations concerning CO2 and CH4 dynamics in the estuaries adjoining the Indian Sundarbans mangrove ecosystem. The review focused on the partial pressure of CO2 and CH4 [pCO2(water) and pCH4(water)] and air-water CO2 and CH4 fluxes and their physical, biogeochemical, and hydrological drivers. The riverine-freshwater-rich Hooghly estuary has always exhibited higher CO2 emissions than the marine-water-dominated Sundarbans estuaries. The mangrove sediment porewater and recirculated groundwater were rich in pCO2(water) and pCH4(water), enhancing their load in the adjacent estuaries. Freshwater-seawater admixing, photosynthetically active radiation, primary productivity, and porewater/groundwater input were the principal factors that regulated pCO2(water) and pCH4(water) and their fluxes. Higher chlorophyll-a concentrations, indicating higher primary production, led to the furnishing of more organic substrates that underwent anaerobic degradation to produce CH4 in the water column. The northern Bay of Bengal seawater had a high carbonate buffering capacity that reduced the pCO2(water) and water-to-air CO2 fluxes in the Sundarbans estuaries. Several authors traced the degradation of organic matter to DIC, mainly following the denitrification pathway (and pathways between aerobic respiration and carbonate dissolution). Overall, this review collated the significant findings on the carbon biogeochemistry of Sundarbans estuaries and discussed the areas that require attention in the future.
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Affiliation(s)
- Isha Das
- School of Oceanographic Studies, Jadavpur University, Kolkata 700032, India
| | - Abhra Chanda
- School of Oceanographic Studies, Jadavpur University, Kolkata 700032, India
| | - Anirban Akhand
- Department of Ocean Science, Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Sugata Hazra
- School of Oceanographic Studies, Jadavpur University, Kolkata 700032, India
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de Souza Viana LM, Constantino WD, Tostes ECL, Luze FHR, de Barros Salomão MSM, de Jesus TB, de Carvalho CEV. Seasonal variation, contribution and dynamics of trace elements in the drainage basin and estuary of the Serinhaém river, BA. MARINE POLLUTION BULLETIN 2023; 188:114653. [PMID: 36764148 DOI: 10.1016/j.marpolbul.2023.114653] [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: 11/01/2022] [Revised: 01/15/2023] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
In the present study a mass balance calculation was used to quantify trace elements (Al, Ba, Cd, Cr, Cu, Fe, Mn, Pb, Ti, V and Zn) fluxes exported from the Serinhaém River estuary to the Atlantic Ocean. The studied elements exportation in the particulate fraction showed higher fluxes in the first sampling campaign and a high export rate to the Atlantic Ocean during this period. The physical-chemical parameters showed the highest values in sampling campaign 1. These variations are probably the cause of the different trace elements behavior in fluvial and estuarine areas, where removal and addition processes between particulate and dissolved phases took place, affecting distribution coefficient and fluxes to the Atlantic Ocean. EPA ecosystems present values in accordance with Brazilian legislation for pristine areas, however, monitoring programs must be carried out in the region, to avoid future environmental problems.
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Affiliation(s)
- Luísa Maria de Souza Viana
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Wendel Dias Constantino
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Eloá Côrrea Lessa Tostes
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Felipe Henrique Rossi Luze
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Marcos Sarmet Moreira de Barros Salomão
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Taíse Bonfim de Jesus
- Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana, Feira de Santana, Bahia, Brazil
| | - Carlos Eduardo Veiga de Carvalho
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia, CEP: 28013-602 Campos dos Goytacazes, Rio de Janeiro, Brazil
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N.H. Sarjuni M, A.M. Dolit S, K. Khamis A, Abd-Aziz N, R. Azman N, A. Asli U. Regenerating Soil Microbiome: Balancing Microbial CO 2 Sequestration and Emission. CARBON SEQUESTRATION 2022. [DOI: 10.5772/intechopen.104740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Soil microbiome plays a significant role in soil’s ecosystem for soils to be physically and biologically healthy. Soil health is fundamental for plant growth and crops productivity. In the introduction part, the roles and dynamics of the microbial community in soils, primarily in the cycle of soil organic carbon and CO2 release and absorption, are deliberated. Next, the impact of crop management practices and climate change on the soil carbon balance are described, as well as other issues related to soil degradation, such as unbalanced nutrient recycling and mineral weathering. In response to these issues, various approaches to soil regeneration have been developed in order to foster an efficient and active soil microbiome, thereby balancing the CO2 cycle and carbon sequestration in the soil ecosystem.
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Mamidala HP, Ganguly D, Ramachandran P, Reddy Y, Selvam AP, Singh G, Banerjee K, Robin RS, Ramachandran R. Distribution and dynamics of particulate organic matter in Indian mangroves during dry period. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:64150-64161. [PMID: 35471763 DOI: 10.1007/s11356-022-20322-x] [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: 08/12/2021] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
The distribution and possible sources of particulate organic carbon (POC) and particulate nitrogen (PN) in seven mangroves ecosystems along the east and west coast of India were examined, to understand their contribution to coastal biogeochemistry. Suspended particulate matter (SPM) concentration in mangrove waters were about ~ 1.6-fold higher in west coast (Gulf of Kachchh (GOK), Mandovi-Zuari (MA-ZU) and Karwar-Kumta (KR-KU)], whereas the mean POC content in SPM along east coast [Sundarbans (SUN), Bhitarkanika (BHK), Coringa (COR) and Pichavaram-Muthupet (PI-MU)] was nearly two times higher than the west coast (1.97 ± 0.91% and 1.06 ± 0.29%), respectively. The results indicated that the influence of the land-based contaminants on the water quality parameters (dissolved oxygen, pH, salinity, nutrients and chlorophyll-a, etc.), which primarily regulated the distribution and transformation of organic carbon in these mangrove waters. Among the studied systems, an extremely high DOC/POC ratio (5.72 ± 1.64) with low pH and DO in COR waters clearly indicated the labile nature of the organic matter influenced by anthropogenic stress. Strong correlation between POC and PN indicated a similar origin in particulate organic matter. The ratios of POC/PN and POC/Chl-a showed significant spatial variation ranging from 5.5 to 18.7 and 126 to 1057, respectively. The results indicated that significant fraction of in-situ primary production contributed to particulate organic matter (POM) pool in all Indian mangrove waters except the GOK and the SUN waters, where sediment resuspension and mangrove derived organic matter were the dominant POM sources.
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Affiliation(s)
- Harikrishna Prasad Mamidala
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Dipnarayan Ganguly
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Purvaja Ramachandran
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India.
| | - Yudhistir Reddy
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Arumughan Paneer Selvam
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Gurmeet Singh
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Kakolee Banerjee
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Radhakrishnan Subhadra Robin
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
| | - Ramesh Ramachandran
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Chennai, 600 025, India
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Zhao X, Rivera-Monroy VH, Farfán LM, Briceño H, Castañeda-Moya E, Travieso R, Gaiser EE. Tropical cyclones cumulatively control regional carbon fluxes in Everglades mangrove wetlands (Florida, USA). Sci Rep 2021; 11:13927. [PMID: 34230502 PMCID: PMC8260777 DOI: 10.1038/s41598-021-92899-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/09/2021] [Indexed: 11/11/2022] Open
Abstract
Mangroves are the most blue-carbon rich coastal wetlands contributing to the reduction of atmospheric CO2 through photosynthesis (sequestration) and high soil organic carbon (C) storage. Globally, mangroves are increasingly impacted by human and natural disturbances under climate warming, including pervasive pulsing tropical cyclones. However, there is limited information assessing cyclone's functional role in regulating wetlands carbon cycling from annual to decadal scales. Here we show how cyclones with a wide range of integrated kinetic energy (IKE) impact C fluxes in the Everglades, a neotropical region with high cyclone landing frequency. Using long-term mangrove Net Primary Productivity (Litterfall, NPPL) data (2001-2018), we estimated cyclone-induced litterfall particulate organic C (litter-POC) export from mangroves to estuarine waters. Our analysis revealed that this lateral litter-POC flux (71-205 g C m-2 year-1)-currently unaccounted in global C budgets-is similar to C burial rates (69-157 g C m-2 year-1) and dissolved inorganic carbon (DIC, 61-229 g C m-2 year-1) export. We proposed a statistical model (PULITER) between IKE-based pulse index and NPPL to determine cyclone's impact on mangrove role as C sink or source. Including the cyclone's functional role in regulating mangrove C fluxes is critical to developing local and regional climate change mitigation plans.
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Affiliation(s)
- Xiaochen Zhao
- Department of Oceanography and Coastal Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA, 70803, USA.
| | - Victor H Rivera-Monroy
- Department of Oceanography and Coastal Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA, 70803, USA.
| | - Luis M Farfán
- Unidad La Paz, Centro de Investigación Científica y de Educación Superior de Ensenada, Baja California Sur, Mexico
| | - Henry Briceño
- Institute of Environment, Florida International University, Miami, FL, 33199, USA
| | | | - Rafael Travieso
- Institute of Environment, Florida International University, Miami, FL, 33199, USA
| | - Evelyn E Gaiser
- Institute of Environment, Florida International University, Miami, FL, 33199, USA
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Henriques M, Granadeiro JP, Piersma T, Leão S, Pontes S, Catry T. Assessing the contribution of mangrove carbon and of other basal sources to intertidal flats adjacent to one of the largest West African mangrove forests. MARINE ENVIRONMENTAL RESEARCH 2021; 169:105331. [PMID: 33878552 DOI: 10.1016/j.marenvres.2021.105331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/24/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
Mangrove forests are productive habitats and major potential exporters of organic matter and nutrients to adjacent habitats. Here we examine the extent to which mangrove carbon is transferred to adjacent intertidal food webs in the second largest mangrove-covered area in Africa, in Guinea-Bissau. Applying stable isotope analysis and mixing models, we made comparisons at two spatial scales: (1) a large scale, comparing intertidal flats with (mangrove sites) and without (control sites) adjacent mangrove forests regarding the carbon isotopic signature of macrozoobenthos and sediment organic matter (SOM), and the relative importance of potential primary food sources in sustaining macrozoobenthos, and (2) a fine scale, performing stable carbon isotope measurements along 200 m transects from the coastline out to open intertidal flats, to trace mangrove carbon in macrozoobenthos and in the SOM. We found no evidence that mangrove carbon sustains intertidal food webs, despite SOM being significantly more depleted in 13C in mangrove sites. Mangrove leaves had the lowest relative contribution to the diet of macrozoobenthos, while macroalgae, benthic microalgae and POM showed variable but overall relevant contributions. Yet, at a smaller scale, mangrove carbon was detectable in SOM and in most macrozoobenthos, being strongest within 50 m of the mangrove edge and quickly fading with increasing distance. Our results suggest that there is only a marginal input of mangrove carbon into the food webs of unvegetated intertidal flats. Still, this leaves open the possibility of mangrove forests acting as sources of dissolved inorganic carbon and processed nitrogen, which can be assimilated by the algae and subsequently fuel adjacent food webs.
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Affiliation(s)
- Mohamed Henriques
- Centro de Estudos do Ambiente e do Mar (CESAM), Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal; Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, the Netherlands.
| | - José Pedro Granadeiro
- Centro de Estudos do Ambiente e do Mar (CESAM), Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
| | - Theunis Piersma
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, the Netherlands; NIOZ - Royal Netherlands Institute for Sea Research, Department of Coastal Systems, the Netherlands
| | - Seco Leão
- Village of Menegue, Island of Canhabaque, Bijagos archipelago, Guinea-Bissau
| | - Samuel Pontes
- Instituto da Biodiversidade e Áreas Protegidas Dr. Alfredo Simão da Silva - IBAP, Bissau, Guinea-Bissau
| | - Teresa Catry
- Centro de Estudos do Ambiente e do Mar (CESAM), Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
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Senger DF, Saavedra Hortua DA, Engel S, Schnurawa M, Moosdorf N, Gillis LG. Impacts of wetland dieback on carbon dynamics: A comparison between intact and degraded mangroves. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:141817. [PMID: 32891992 DOI: 10.1016/j.scitotenv.2020.141817] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 08/15/2020] [Accepted: 08/18/2020] [Indexed: 06/11/2023]
Abstract
Mangroves are effective blue carbon sinks and are the most carbon rich ecosystems on earth. However, their areal extent has declined by over one-third in recent decades. Degraded mangrove forests result in reduced carbon captured and lead to release of stored carbon into the atmosphere by CO2 emission. The aim of this study was to assess changes in carbon dynamics in a gradually degrading mangrove forest on Bonaire, Dutch Caribbean. Remote sensing techniques were applied to estimate the distribution of intact and degraded mangroves. Forest structure, sediment carbon storage, sediment CO2 effluxes and dissolved organic and inorganic carbon in pore and surface waters across intact and degraded parts were assessed. On average intact mangroves showed 31% sediment organic carbon in the upper 30 cm compared to 20% in degraded mangrove areas. A loss of 1.51 MgCO2 ha-1 yr-1 for degraded sites was calculated. Water samples showed a hypersaline environment in the degraded mangrove area averaging 93 which may have caused mangrove dieback. Sediment CO2 efflux within degraded sites was lower than values from other studies where degradation was caused by clearing or cutting, giving new insights into carbon dynamics in slowly degrading mangrove systems. Results of water samples agreed with previous studies where inorganic carbon outwelled from mangroves might enhance ecosystem connectivity by potentially buffering ocean acidification locally. Wetlands will be impacted by a variety of stressors resulting from a changing climate. Results from this study could inform scientists and stakeholders on how combined stresses, such as climate change with salinity intrusion may impact mangrove's blue carbon sink potential and highlight the need of future comparative studies of intact versus degraded mangrove stands.
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Affiliation(s)
- D F Senger
- University of Bremen, 28359 Bremen, Germany.
| | | | - S Engel
- Stichting Nationale Parken Bonaire - STINAPA, P.O. BOX 368, Bonaire, Dutch Caribbean, the Netherlands
| | | | - N Moosdorf
- Leibniz Center for Marine Tropical Research - ZMT, 28359 Bremen, Germany; Kiel University, Institute of Geosciences, Kiel, Germany
| | - L G Gillis
- Leibniz Center for Marine Tropical Research - ZMT, 28359 Bremen, Germany
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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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Abstract
Despite the recognized organic carbon (OC) sequestration potential of mangrove forests, the ongoing climate change and anthropogenic disturbances pose a great threat to these ecosystems. However, we currently lack the ability to mechanically understand and predict the consequences of such impacts, primarily because mechanisms underlying OC stabilization in these ecosystems remain elusive. Research into OC stabilization has focused on terrestrial soils and marine sediments for decades, overlooking the vegetated coastal ecosystems including mangroves. In terrestrial soils and marine sediments, it is widely accepted that OC stabilization is the integrated consequence of OM’s inherent recalcitrance, physical protection, and interactions with minerals and metals. However, related discussion is rarely done in mangrove soils, and recalcitrance of roots and high net ecosystem production (high primary production and low heterotrophic respiration) have been considered as a primary OC sequestration mechanism in mangrove peat and mineral soils, respectively. This review presents the available information on the mechanisms underlying OC stabilization in mangrove soils and highlights research questions that warrant further investigation. Primary OC stabilization mechanisms differ between mangrove peat and mineral soils. In mangrove mineral soils, physico-chemical stabilization processes are important, yet grossly understudied OC stabilization mechanisms. In mangrove peat, recalcitrance of mangrove roots and the inhibition of phenoloxidase under the anoxic condition may be the primary OC stabilization mechanisms. Salinity-induced OC immobilization likely plays a role in both type of soils. Finally, this review argues that belowground production and allochthonous inputs in mangrove forests are likely underestimated. More studies are needed to constrain C budgets to explain the enigma that mangrove OC keeps accumulating despite much higher decomposition (especially by large lateral exports) than previously considered.
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Carbon Cycling in the World’s Mangrove Ecosystems Revisited: Significance of Non-Steady State Diagenesis and Subsurface Linkages between the Forest Floor and the Coastal Ocean. FORESTS 2020. [DOI: 10.3390/f11090977] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Carbon cycling within the deep mangrove forest floor is unique compared to other marine ecosystems with organic carbon input, mineralization, burial, and advective and groundwater export pathways being in non-steady-state, often oscillating in synchrony with tides, plant uptake, and release/uptake via roots and other edaphic factors in a highly dynamic and harsh environment. Rates of soil organic carbon (CORG) mineralization and belowground CORG stocks are high, with rapid diagenesis throughout the deep (>1 m) soil horizon. Pocketed with cracks, fissures, extensive roots, burrows, tubes, and drainage channels through which tidal waters percolate and drain, the forest floor sustains non-steady-state diagenesis of the soil CORG, in which decomposition processes at the soil surface are distinct from those in deeper soils. Aerobic respiration occurs within the upper 2 mm of the soil surface and within biogenic structures. On average, carbon respiration across the surface soil-air/water interface (104 mmol C m−2 d−1) equates to only 25% of the total carbon mineralized within the entire soil horizon, as nearly all respired carbon (569 mmol C m−2 d−1) is released in a dissolved form via advective porewater exchange and/or lateral transport and subsurface tidal pumping to adjacent tidal waters. A carbon budget for the world’s mangrove ecosystems indicates that subsurface respiration is the second-largest respiratory flux after canopy respiration. Dissolved carbon release is sufficient to oversaturate water-column pCO2, causing tropical coastal waters to be a source of CO2 to the atmosphere. Mangrove dissolved inorganic carbon (DIC) discharge contributes nearly 60% of DIC and 27% of dissolved organic carbon (DOC) discharge from the world’s low latitude rivers to the tropical coastal ocean. Mangroves inhabit only 0.3% of the global coastal ocean area but contribute 55% of air-sea exchange, 14% of CORG burial, 28% of DIC export, and 13% of DOC + particulate organic matter (POC) export from the world’s coastal wetlands and estuaries to the atmosphere and global coastal ocean.
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14
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Chanda A, Das S, Bhattacharyya S, Akhand A, Das I, Samanta S, Choudhury SB, Hazra S. CO 2 effluxes from an urban tidal river flowing through two of the most populated and polluted cities of India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:30093-30107. [PMID: 32447735 DOI: 10.1007/s11356-020-09254-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Urbanized rivers flowing through polluted megacities receive substantial amount of carbon from domestic sewage and industrial effluents which can significantly alter the air-water CO2 flux rates. In this regard, we quantified the partial pressure of CO2 in the surface water (pCO2(water)), air-water CO2 fluxes, and associated biogeochemical parameters in the Hooghly River, India, flowing through two of the most polluted cities of the country, Kolkata and Howrah, over a complete annual cycle during spring tidal phase (SP) and neap tidal phase (NP). This urbanized part of Hooghly River was always supersaturated with CO2 having an annual mean pCO2(water) and air-water CO2 flux of ~ 3800 μatm and ~ 49 mol C m-2 year-1, respectively. Significant seasonal variability was observed for both pCO2(water) and air-water CO2 flux (pre-monsoon, 3038 ± 539 μatm and 5049 ± 964 μmol m-2 h-1; monsoon, 4609 ± 711 μatm and 7918 ± 1400 μmol m-2 h-1; post-monsoon, 2558 ± 258 μatm and 4048 ± 759 μmol m-2 h-1, respectively). Monthly mean pH and total alkalinity varied from 7.482 to 8.099 and from 2437 to 4136 μmol kg-1, respectively, over the annual cycle. pCO2(water) showed significant positive correlation with turbidity and negative correlation with electrical conductivity and gross primary productivity (GPP). High water discharge could have facilitated high turbidity, especially during the monsoon season, which led to depletion in GPP and enhancement in pCO2(water) which in turn led to very high CO2 effluxes. The CO2 efflux rate in this urbanized riverine stretch was substantially higher than that observed in previous studies carried out in the less urbanized estuarine stretch of Hooghly. This indicates that the presence of highly urbanized and polluted metropolis potentially enhanced the pCO2(water) and CO2 effluxes of this river. Similar observations were made recently in some Asian and Australian urban rivers.
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Affiliation(s)
- Abhra Chanda
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India.
| | - Sourav Das
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India
| | - Sourav Bhattacharyya
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India
| | - Anirban Akhand
- Coastal and Estuarine Environment Research Group, Port and Airport Research Institute, 3-1-1, Nagase, Yokosuka, Kanagawa, 239-0826, Japan
| | - Isha Das
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India
| | - Sourav Samanta
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India
| | - Saroj Bandhu Choudhury
- National Remote Sensing Centre, Department of Space, Government of India, Hyderabad, Telengana, 500042, India
| | - Sugata Hazra
- School of Oceanographic Studies, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata, West Bengal, 700032, India
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15
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Palanivel PS, Veeraiyan B, Palingam G, Perumal M. Influence of physico-chemical parameters and pCO2 concentration on mangroves-associated polychaetes at Pichavaram, southeast coast of India. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-1581-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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16
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Maher DT, Call M, Santos IR, Sanders CJ. Beyond burial: lateral exchange is a significant atmospheric carbon sink in mangrove forests. Biol Lett 2019; 14:rsbl.2018.0200. [PMID: 30021861 DOI: 10.1098/rsbl.2018.0200] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/20/2018] [Indexed: 11/12/2022] Open
Abstract
The blue carbon paradigm has evolved in recognition of the high carbon storage and sequestration potential of mangrove, saltmarsh and seagrass ecosystems. However, fluxes of the potent greenhouse gases CH4 and N2O, and lateral export of carbon are often overlooked within the blue carbon framework. Here, we show that the export of dissolved inorganic carbon (DIC) and alkalinity is approximately 1.7 times higher than burial as a long-term carbon sink in a subtropical mangrove system. Fluxes of methane offset burial by approximately 6%, while the nitrous oxide sink was approximately 0.5% of burial. Export of dissolved organic carbon and particulate organic carbon to the coastal zone is also significant and combined may account for an atmospheric carbon sink similar to burial. Our results indicate that the export of DIC and alkalinity results in a long-term atmospheric carbon sink and should be incorporated into the blue carbon paradigm when assessing the role of these habitats in sequestering carbon and mitigating climate change.
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Affiliation(s)
- Damien T Maher
- Southern Cross Geoscience, Southern Cross University, Lismore, New South Wales 2480, Australia .,School of Environment, Science and Engineering, Southern Cross University, Lismore, New South Wales 2480, Australia
| | - Mitchell Call
- Southern Cross Geoscience, Southern Cross University, Lismore, New South Wales 2480, Australia.,School of Environment, Science and Engineering, Southern Cross University, Lismore, New South Wales 2480, Australia
| | - Isaac R Santos
- School of Environment, Science and Engineering, Southern Cross University, Lismore, New South Wales 2480, Australia.,National Marine Science Centre, Southern Cross University, Coffs Harbour, New South Wales 2450, Australia
| | - Christian J Sanders
- School of Environment, Science and Engineering, Southern Cross University, Lismore, New South Wales 2480, Australia.,National Marine Science Centre, Southern Cross University, Coffs Harbour, New South Wales 2450, Australia
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17
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Lei P, Zhong H, Duan D, Pan K. A review on mercury biogeochemistry in mangrove sediments: Hotspots of methylmercury production? THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 680:140-150. [PMID: 31112813 DOI: 10.1016/j.scitotenv.2019.04.451] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 04/30/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Wetlands are highly productive and biologically diverse environments that provide numerous ecosystem services, but can also be sources of methylmercury (MeHg) production and export. Mangrove wetlands contribute up to 15% of the coastal sediment carbon storage and ~10% of the particulate terrestrial carbon exported to the ocean. Thus, mercury (Hg) methylation in mangrove sediments and subsequent MeHg output to adjacent waters could have a great impact on global Hg cycling. In this review, we provide a comprehensive analysis of the literature on worldwide Hg concentrations in mangrove ecosystems, and the results reveal that a large range of total Hg (THg) and MeHg concentrations is detected in mangrove systems. Then, we discuss the potential roles of organic matter (OM) in controlling the Hg biogeochemistry in mangrove sediments. The intense OM decomposition by anoxic reduction (e.g., sulfate reduction) drastically affects sediment chemistries, such as redox potential, pH, and sulfur speciation, all of which may have a great impact on MeHg production. While the outwelling of carbon from mangroves has been extensively examined, little is known about their roles in exporting MeHg to adjacent waters. Our understanding of Hg biogeochemical processes in mangrove systems is constrained by the limited MeHg data and a lack of in-depth studies on the Hg methylation potential in this ecologically important environment. More efforts are needed to gain better insights into the contributions mangrove wetlands to the global Hg cycle.
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Affiliation(s)
- Pei Lei
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China; State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210046, China
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210046, China; Environmental and Life Science Program (EnLS), Trent University, Peterborough, Ontario, Canada
| | - Dandan Duan
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Ke Pan
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
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18
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Abstract
Calcium carbonates (CaCO3) often accumulate in mangrove and seagrass sediments. As CaCO3 production emits CO2, there is concern that this may partially offset the role of Blue Carbon ecosystems as CO2 sinks through the burial of organic carbon (Corg). A global collection of data on inorganic carbon burial rates (Cinorg, 12% of CaCO3 mass) revealed global rates of 0.8 TgCinorg yr−1 and 15–62 TgCinorg yr−1 in mangrove and seagrass ecosystems, respectively. In seagrass, CaCO3 burial may correspond to an offset of 30% of the net CO2 sequestration. However, a mass balance assessment highlights that the Cinorg burial is mainly supported by inputs from adjacent ecosystems rather than by local calcification, and that Blue Carbon ecosystems are sites of net CaCO3 dissolution. Hence, CaCO3 burial in Blue Carbon ecosystems contribute to seabed elevation and therefore buffers sea-level rise, without undermining their role as CO2 sinks. Calcium carbonates (CaCO3) often accumulate in mangrove and seagrass sediments. Here the authors conducted a meta-analysis of inorganic carbon burial rates in mangrove and seagrass sediments and found that CaCO3 burial contributes to Blue Carbon ecosystems’ capacity to offset sea-level rise without undermining the role as CO2 sinks.
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19
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Mandal SK, Ray R, González AG, Mavromatis V, Pokrovsky OS, Jana TK. State of rare earth elements in the sediment and their bioaccumulation by mangroves: a case study in pristine islands of Indian Sundarban. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:9146-9160. [PMID: 30715704 DOI: 10.1007/s11356-019-04222-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
The mangrove ecosystems are known to efficiently sequester trace metals both in sediments and plant biomass. However, less is known about the chemistry of rare earth elements (REE) in the coastal environments, especially in the world's largest mangrove province, the Sundarban. Here, the concentration of REE in the sediment and plant organs of eight dominant mangrove species (mainly Avicennia sp.) in the Indian Sundarban was measured to assess REE sources, distribution, and bioaccumulation state. Results revealed that light REE (LREE) were more concentrated than the heavy REE (HREE) (128-144 mg kg-1 and 12-15 mg kg-1, respectively) in the mangrove sediments, with a relatively weak positive europium anomaly (Eu/Eu* = 1.03-1.14) with respect to North American shale composite. The primary source of REE was most likely linked to aluminosilicate weathering of crustal materials, and the resultant increase in LREE in the detritus. Vertical distribution of REE in one of the long cores from Lothian Island was altered by mangrove root activity and dependent on various physicochemical properties in the sediment (e.g., Eh, pH, organic carbon, and phosphate). REE uptake by plants was higher in the below-ground parts than in the above-ground plant tissues (root = 3.3 mg kg-1, leaf + wood = 1.7 mg kg-1); however, their total concentration was much lower than in the sediment (149.5 mg kg-1). Species-specific variability in bioaccumulation factor and translocation factor was observed indicating different REE partitioning and varying degree of mangrove uptake efficiency. Total REE stock in plant (above + live below ground) was estimated to be 168 g ha-1 with LREE contributing ~ 90% of the stock. This study highlighted the efficiency of using REE as a biological proxy in determining the degree of bioaccumulation within the mangrove environment.
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Affiliation(s)
- Sanjay K Mandal
- Department of Marine Science, Calcutta University, Kolkata, 70019, India
- Department of Chemistry, Sundarban Hazi Desarat College, South 24 Parganas, Pathankhali, 743611, India
| | - Raghab Ray
- LEMAR (Laboratoire des Sciences de l'Environnement Marin), UMR 6539, (CNRS-UBO-IRD- IFREMER), 29280, Plouzané, France.
- Department of Chemical Oceanography, Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, 277-8564, Japan.
| | - Aridane G González
- LEMAR (Laboratoire des Sciences de l'Environnement Marin), UMR 6539, (CNRS-UBO-IRD- IFREMER), 29280, Plouzané, France
- Instituto de Oceanografía y Cambio Global, IOCAG, Universidad de Las Palmas de Gran Canaria, ULPGC, 35017, Las Palmas de Gran Canaria, Spain
| | | | - Oleg S Pokrovsky
- GET (Géosciences Environnement Toulouse) UMR 5563 CNRS, 31400, Toulouse, France
- BIO-GEO-CLIM Laboratory, Tomsk State University, Tomsk, Russia, 634050
- N. Laverov Federal Center for Integrated Arctic Research, IEPS, Russian Academy of Sciences, Arkhangelsk, Russia, 163000
| | - Tapan K Jana
- Department of Marine Science, Calcutta University, Kolkata, 70019, India
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Li SB, Chen PH, Huang JS, Hsueh ML, Hsieh LY, Lee CL, Lin HJ. Factors regulating carbon sinks in mangrove ecosystems. GLOBAL CHANGE BIOLOGY 2018; 24:4195-4210. [PMID: 29790233 DOI: 10.1111/gcb.14322] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 02/01/2018] [Accepted: 04/24/2018] [Indexed: 05/06/2023]
Abstract
Mangroves are recognized as one of the richest carbon storage systems. However, the factors regulating carbon sinks in mangrove ecosystems are still unclear, particularly in the subtropical mangroves. The biomass, production, litterfall, detrital export and decomposition of the dominant mangrove vegetation in subtropical (Kandelia obovata) and tropical (Avicennia marina) Taiwan were quantified from October 2011 to July 2014 to construct the carbon budgets. Despite the different tree species, a principal component analysis revealed the site or environmental conditions had a greater influence than the tree species on the carbon processes. For both species, the net production (NP) rates ranged from 10.86 to 27.64 Mg C ha-1 year-1 and were higher than the global average rate due to the high tree density. While most of the litterfall remained on the ground, a high percentage (72%-91%) of the ground litter decomposed within 1 year and fluxed out of the mangroves. However, human activities might cause a carbon flux into the mangroves and a lower NP rate. The rates of the organic carbon export and soil heterotrophic respiration were greater than the global mean values and those at other locations. Only a small percentage (3%-12%) of the NP was stored in the sediment. The carbon burial rates were much lower than the global average rate due to their faster decomposition, indicating that decomposition played a critical role in determining the burial rate in the sediment. The summation of the organic and inorganic carbon fluxes and soil heterotrophic respiration well exceeded the amount of litter decomposition, indicating an additional source of organic carbon that was unaccounted for by decomposition in the sediment. Sediment-stable isotope analyses further suggest that the trapping of organic matter from upstream rivers or adjacent waters contributed more to the mangrove carbon sinks than the actual production of the mangrove trees.
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Affiliation(s)
- Shi-Bo Li
- Department of Life Sciences and Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung, Taiwan
| | - Po-Hung Chen
- Department of Life Sciences and Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung, Taiwan
| | - Jih-Sheng Huang
- Department of Life Sciences and Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung, Taiwan
| | - Mei-Li Hsueh
- Endemic Species Research Institute, Chichi, Taiwan
| | | | - Chen-Lu Lee
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Hsing-Juh Lin
- Department of Life Sciences and Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung, Taiwan
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
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