文献类型：期刊文献

英文题名：Sources and temporal-spatial variations of sedimentary organic matter and black carbon in Zhanjiang Bay: Insights into coastal carbon burial

作者：Zeng, Yuanhao[1,2];Lao, Qibin[1,2,3,4];Chen, Chunqing[1,2];Zeng, Hui[1,2];Chen, Fajin[1,2,3,4]

机构：[1]Guangdong Ocean Univ, Coll Ocean & Meteorol, Zhanjiang 524088, Peoples R China;[2]Guangdong Ocean Univ, Sch Chem & Environm, Zhanjiang 524088, Peoples R China;[3]Guangdong Ocean Univ, Key Lab Coastal Ocean Variat & Disaster Predict, Zhanjiang 524088, Peoples R China;[4]Guangdong Ocean Univ, Dept Educ Guangdong Prov, Key Lab Climate Resources & Environm Continental S, Zhanjiang 524088, Peoples R China

年份：2026

卷号：213

外文期刊名：MARINE ENVIRONMENTAL RESEARCH

收录：SCI-EXPANDED(收录号：WOS:001622114400001)、、WOS

基金：This study was supported by the National Natural Science Founda-tion of China (42276047) .

语种：英文

外文关键词：Black carbon; Sedimentary organic matter; Sources; Carbon and nitrogen stable isotopes; Temporal-spatial variations

外文摘要：Black carbon (BC) is a key oceanic carbon sink, particularly in coastal bays, owing to its persistent and refractory properties. However, understanding of the sources and temporal-spatial variations of sedimentary BC in coastal bays remains limited. Analysis of spatiotemporal variations in BC, total organic carbon (TOC), total nitrogen (TN), and their isotopic compositions (delta 13CTOC, delta 15N,delta 13CBC), as well as C/N and BC/TOC ratios, in surface sediments of Zhanjiang Bay (ZJB) over four seasons were conducted to elucidate the seasonal dynamics of organic carbon in the bay. Our results showed that terrestrial organic matter was found to contribute 55 %-62 % of TOC in sediments across all four seasons. Fossil fuel combustion was the primary source of BC in the upper bay, while biomass burning dominated in the lower bay. Significantly higher TOC and BC concentrations in the upper bay than in the lower bay are driven by two primary factors. Firstly, the finer sediment grain size (the average content of silt and clay in the four seasons: 85.9 % +/- 18.2 %) due to aquaculture activities in the upper bay promotes the preservation of TOC and BC. Secondly, a frontal system between the upper and lower bay traps organic matter derived from the terrestrial input and local anthropogenic activities, thereby enhancing the adsorption capacity of upper bay sediments. These factors have important implications for global carbon cycling and sequestration, and further highlight the considerable impact of oyster farming and weak hydrodynamic conditions on the burial of coastal sedimentary organic matter.