文献类型：期刊文献

中文题名：珠江口及邻近海域表层沉积物有机碳和黑碳的来源及空间分布特征

英文题名：Sources and spatial distributions of organic carbon and black carbon in surface sediments from the Pearl River Estuary and the adjacent South China Sea

作者：黄志文[1,2];程健森[3];黄超[3];胡建芳[1,2]

机构：[1]中国科学院广州地球化学研究所,深地过程与战略矿产资源全国重点实验室,广东广州510640;[2]中国科学院大学,北京100049;[3]广东海洋大学海洋与气象学院/广东省沿海海洋变化与灾害预警实验室,广东湛江524088

年份：2025

卷号：54

期号：5

起止页码：849

中文期刊名：地球化学

外文期刊名：Geochimica

收录：北大核心2023、、北大核心

基金：国家自然科学基金重大项目(41991252)资助。

语种：中文

中文关键词：沉积有机质;黑碳;陆源输入;珠江口

外文关键词：sediment organic matter;black carbon;terrestrial input;Pearl River Estuary

中文摘要：珠江口是世界大型河口之一,位于近百年来人类活动剧烈区域。研究陆源有机碳对理解气候变化和人类活动影响下的河口碳循环具有重要科学和现实意义。黑碳(BC)是有机碳的重要组成部分,目前对珠江口BC来源和运输途径了解较少,不利于探讨人类活动对该区域地球化学环境的影响。本研究对珠江口及邻近海域表层沉积物有机碳和BC进行研究,分析沉积物粒度、总有机碳(TOC)及其稳定C同位素(δ^(13)C_(TOC))、总氮(TN)、BC及其稳定C同位素(δ^(13)C_(BC))组成。结果显示:沉积物TOC含量为0.24%~1.17%,TN为0.05%~0.18%,δ^(13)C_(TOC)为?26.0‰~?20.7‰;BC含量为0.52~2.97 mg/g,δ^(13)C_(BC)为?25.8‰~?22.5‰。源解析和相关性分析表明,向外海方向,TOC含量和陆源有机碳含量减少,而海源有机碳含量增大,陆源输入和河口环境共同制约沉积有机碳的组成特征和空间分布。沉积物粒度和δ^(13)C_(BC)表明,河流输入和大气沉降是BC入海的主要途径。对不同来源BC相对贡献比例的定量计算结果显示,沉积物BC主要来自化石燃料,表明人类活动显著影响珠江口海域BC的沉积埋藏。

外文摘要：The Pearl River Estuary,a key estuarine system in the world,has been profoundly affected by human activities over the past century.Investigating the terrestrial organic carbon in this area is of crucial scientific and practical significance for comprehending the carbon cycle in estuaries under the influence of climate change and human activities.Black carbon is a significant constituent of organic carbon.However,research on black carbon in the Pearl River Estuary is relatively scarce,leading to a limited understanding of its sources and transportation pathways.In this study,the organic carbon and black carbon of surface sediments in the Pearl River Estuary and the adjacent South China Sea were investigated.The sediment particle size,total organic carbon(TOC)and its stable carbon isotope(δ^(13)C_(TOC)),total nitrogen(TN),black carbon(BC)and its stable carbon isotopeδ^(13)C_(BC) were analyzed.The results revealed that:TOC content in sediments ranged from 0.24%to 1.17%,TN from 0.05%to 0.18%,andδ^(13)C_(TOC) from?26.0‰to?20.7‰;BC content ranged from 0.52 mg/g to 2.97 mg/g,withδ^(13)C_(BC) ranging from?25.8‰to?22.5‰.Source partitioning and correlation analysis revealed that the decrease in TOC content towards the offshore direction,along with an increase in marine OC content,indicated a combined influence of terrestrial input and estuarine environment on the composition and spatial distribution of sedimentary organic carbon.Analysis of sediment grain size andδ^(13)C_(BC) indicated that river inputs and atmospheric deposition are the dominant pathways for BC influx into the marine environment.The quantitative assessment of the relative proportion of various sources of BC revealed that the sedimentary BC was mainly derived from fossil fuels,highlighting the significant influence of human activities on BC deposition and burial.