Salt marsh invasion reduces recalcitrant organic carbon pool while increases lateral export of dissolved inorganic carbon in a subtropical mangrove wetland

Lu，Zeyang1,2; Xiao，Kai3; Wang，Fenfang1,2; Wang，Yao1,2; Yu，Qibiao1,2; Chen，Nengwang1,2,4

2023-09-01

10.1016/j.geoderma.2023.116573

Geoderma   Impact Factor & Quartile

0016-7061

1872-6259

Mangrove wetlands are one of the most productive ecosystems and store large amounts of organic carbon (blue carbon). However, mangrove wetlands have been invaded by S. alterniflora-dominated salt marsh globally, the understanding of how this ecological invasion affects carbon cycling in mangroves remains limited. In this study, we conducted intensive investigations and measurements in a subtropical mangrove wetland (S.E. China) to evaluate the impacts of S. alterniflora invasion on sediment organic carbon (SOC) pools, sources, stability, and dissolved inorganic carbon (DIC) export. Results showed that S. alterniflora invasion increased sediment labile organic carbon (LOC) content and decreased the proportion of recalcitrant organic carbon (ROC) compared with other habitats (e.g., mudflat, mangrove, and marsh-mangrove transitional community). The δC values showed that mangroves can provide more SOC and ROC than S. alterniflora. The SOC provided by S. alterniflora mostly consisted of LOC, which was unstable and easily transformed, leading to the higher anaerobic mineralization rate and CO production. Different from the acidic environment of mangrove sediment, the alkaline environment of S. alterniflora sediment preserves more CO in the form of DIC in porewater, which could be transported during the movement of tides. Thus, S. alterniflora potentially exported more DIC to the estuary than mangroves. These findings suggested that S. alterniflora-dominated salt marsh invasion can substantially perturb the mangrove wetlands by reducing ROC pool and potentially increasing the lateral export of DIC.

Blue carbon Ecological invasion Lateral export Mangrove wetlands Recalcitrant organic carbon

SCI

English

Others

National Natural Science Foundation of China["42276171","42177046"] ; National Key Research and Development Program of China[2022YFF0802102]

Agriculture

Soil Science

WOS:001039294000001

ELSEVIER

AGRICULTURAL SCIENCES

2-s2.0-85162230769

Scopus

1.Key Laboratory of the Coastal and Wetland Ecosystems,College of the Environment and Ecology,Xiamen University,Xiamen,China
2.State Key Laboratory of Marine Environment Science,Xiamen University,Xiamen,China
3.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,China
4.National Observation and Research Station for the Taiwan Strait Marine Ecosystem (Xiamen University),Zhangzhou,China

Lu，Zeyang,Xiao，Kai,Wang，Fenfang,et al. Salt marsh invasion reduces recalcitrant organic carbon pool while increases lateral export of dissolved inorganic carbon in a subtropical mangrove wetland[J]. Geoderma,2023,437.

Lu，Zeyang,Xiao，Kai,Wang，Fenfang,Wang，Yao,Yu，Qibiao,&Chen，Nengwang.(2023).Salt marsh invasion reduces recalcitrant organic carbon pool while increases lateral export of dissolved inorganic carbon in a subtropical mangrove wetland.Geoderma,437.

Lu，Zeyang,et al."Salt marsh invasion reduces recalcitrant organic carbon pool while increases lateral export of dissolved inorganic carbon in a subtropical mangrove wetland".Geoderma 437(2023).