Carbonate chemistry and carbon sequestration driven by inorganic carbon outwelling from mangroves and saltmarshes
Year: 2023
Type: article
Abstract: Mangroves and saltmarshes are biogeochemical hotspots storing carbon in sediments and in the ocean following lateral carbon export (outwelling). Coastal seawater pH is modified by both uptake of anthropogenic carbon dioxide and natural biogeochemical processes, e.g., wetland inputs. Here, we investigate how mangroves and saltmarshes influence coastal carbonate chemistry and quantify the contribution of alkalinity and dissolved inorganic carbon (DIC) outwelling to blue carbon budgets. Observations from 45 mangroves and 16 saltmarshes worldwide revealed that >70% of intertidal wetlands export more DIC than alkalinity, potentially decreasing the pH of coastal waters. Porewater-derived DIC outwelling (81 ± 47 mmol m −2 d −1 in mangroves and 57 ± 104 mmol m −2 d −1 in saltmarshes) was the major term in blue carbon budgets. However, substantial amounts of fixed carbon remain unaccounted for. Concurrently, alkalinity outwelling was similar or higher than sediment carbon burial and is therefore a significant but often overlooked carbon sequestration mechanism.
Source: Nature Communications
Authors: Gloria M. S. Reithmaier, Alex Cabral, Anirban Akhand, Matthew J. Bogard, Alberto V. Borges, Steven Bouillon, David J. Burdige, Mitchel Call, Nengwang Chen, Xiaogang Chen, Luiz C. Cotovicz, Meagan J. Eagle, Erik Kristensen, Kevin D. Kroeger, Zeyang Lu, Damien T. Maher, J. Lucas Pérez-Lloréns, Raghab Ray, Pierre Taillardat, Joseph J. Tamborski, Rob C. Upstill-Goddard, Faming Wang, Zhaohui Aleck Wang, Kai Xiao, Yvonne Y. Y. Yau, Isaac R. Santos
Institutions: University of Gothenburg, Hong Kong University of Science and Technology, Port and Airport Research Institute, University of Lethbridge, University of Liège, KU Leuven, Old Dominion University, Southern Cross University, Xiamen University, Westlake University, Universidade Federal do Ceará, Leibniz Institute for Baltic Sea Research Warnemünde, United States Geological Survey, Woods Hole Coastal and Marine Science Center, University of Southern Denmark, Universidad de Cádiz, Atmosphere and Ocean Research Institute, The University of Tokyo, The University of Tokyo, National University of Singapore, NUS Environmental Research Institute, Newcastle University, Chinese Academy of Sciences, Woods Hole Oceanographic Institution, Southern University of Science and Technology
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,290
Funders: Vetenskapsrådet, Göteborgs Universitet
OpenAlex ID: W4389558985