文献类型：期刊文献

英文题名：Sediment organic carbon dynamics and accumulation in estuarine mangrove wetlands

作者：Gong, Jian[1,2,3,4] Liu, Weiwei[1,2,3,4] Li, Wei[1,2,3,4] Cui, Lijuan[1,2,3,4]

第一作者：Gong, Jian

通信作者：Cui, LJ[1];Cui, LJ[2];Cui, LJ[3];Cui, LJ[4]

机构：[1]Chinese Acad Forestry, State Key Lab Wetland Conservat & Restorat, Beijing 100091, Peoples R China;[2]Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Beijing 100091, Peoples R China;[3]Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China;[4]Beijing Key Lab Wetland Ecol Funct & Restorat, Beijing 100091, Peoples R China

年份：2025

卷号：259

外文期刊名：CATENA

收录：;Scopus(收录号：2-s2.0-105011489262);WOS:【SCI-EXPANDED(收录号:WOS:001553124600001)】；

基金：This work is supported from the National Key R & D Program of China (grant: 2022YFF1301000) , the National Natural Science Foundation of China (grant: 72474215 and 72104236) , the Fundamental Research Funds of Chinese Academy of Forestry (grant: CAFYBB2023MB018) .

语种：英文

外文关键词：Mangrove wetland; active OC fractions; organic carbon accumulation rate (OCAR); sediment organic carbon (SOC); SOC source; Decomposition

摘要：Estuarine mangrove wetlands are important carbon sinks, yet the mechanisms driving sediment organic carbon (SOC) accumulation and burial remain insufficiently understood. Here, we present comprehensive insights into the distribution, sources, and decomposition of SOC and its fractions, as well as temporal variations in organic carbon accumulation rate (OCAR), across a land-to-sea gradient in mangrove and unvegetated habitats. Our results show that SOC content and storage are significantly higher in mangrove habitats compared to unvegetated ones, both of which decrease with increasing sediment depth, primarily controlled by bulk density (BD) and sediment water content (SWC). Similarly, the distribution patterns of active organic carbon fractions, including easily oxidizable organic carbon, microbial biomass carbon, and dissolved organic carbon, exhibit similar spatial patterns to SOC across habitats. Stable isotope analyses (delta C-13 and delta N-15) and lignin biomarkers reveal that SOC decomposition is markedly higher in mangrove habitats than in unvegetated areas, potentially driven by plant inputs that enhance microbial processes and accelerate carbon turnover. The contribution of C3 vascular plant-derived terrestrial organic carbon declines significantly along the land-to-sea gradient (from 62.8 % in mangrove habitats to 28.0 % in unvegetated areas), likely due to reduced in situ plant inputs. Structural equation modeling results indicate that sediment accumulation rate (SAR), BD, and SWC are key environmental factors influencing OCAR, while other relevant environmental factors may also contribute. This study enhances our understanding of carbon cycling mechanisms in mangrove wetlands and provides a scientific foundation for their conservation and management.