文献类型：期刊文献

英文题名：Spatiotemporal dynamics of heavy metal transport and biogeochemical self-purification across the estuary-coast continuum: Insights from field incubation experiments and modeling

作者：Peng, Demeng[1,2];Zhang, Jibiao[2];Zhang, Peng[2]

机构：[1]Sun Yat Sen Univ, Sch Marine Sci, Zhuhai 519082, Peoples R China;[2]Guangdong Ocean Univ, Coll Chem & Environm Sci, Zhanjiang 524088, Guangdong, Peoples R China

年份：2026

卷号：275

外文期刊名：OCEAN & COASTAL MANAGEMENT

收录：SCI-EXPANDED(收录号：WOS:001679520600001)、、EI(收录号：20260620040040)、WOS

基金：Thanks for the financial support provided by the Research and Development Projects in Key Areas of Guangdong Province (2020B1111020004) ; the Guangdong Basic and Applied Basic Research Foundation (2023A1515012769) ; Guangdong Basic and Applied Basic Research Foundation (2020A1515110483) .

语种：英文

外文关键词：Heavy metals; Estuary-coast continuum; Biogeochemical self-purification capacity; Zhanjiang bay

外文摘要：Global industrialization has intensified heavy metal pollution in coastal ecosystems, necessitating a better understanding of their transport and self-purification mechanisms for effective environmental protection. However, the transport of heavy metals across the estuary-coastal continuum remains unclear. This study systematically examined the transport and biogeochemical self-purification of heavy metals in Zhanjiang Bay using seasonal field incubation experiments, numerical model and interpretable machine learning. Results showed scavenging rates of Pb (0.161 d(-1)) > Cu (0.138 d(-1)) > Ni (0.136 d(-1)) > Zn (0.136 d(-1)) > Cr (0.088 d(-1)) > Cd (0.081 d(-1)), with the highest rates in the areas of salinity 5-15 and significant seasonal influence. The bay's complex shoreline caused varying pollutant transport capacities among the inner bay, middle bay, and bay mouth. Hydrodynamic modeling showed water residence times reached up to 65 days in the north of Techeng Island and east of Donghai Dam during the dry season, but were less than 10 days at the bay mouth. However, incorporating the biochemical process accelerated heavy metal self-purification, the water residence time in the north of Techeng Island and the east of Donghai Dam was shortened to within 20 days. After terrestrial heavy metals enter Zhanjiang Bay, from the Suixi River estuary to the bay mouth, the self-purification process alternates between being dominated by physical self-purification and biochemical self-purification. Temperature, suspended particulate matter, and chlorophyll-a were identified as key factors regulating biochemical self-purification, which were strongly modulated by seasonal changes. This study provided important data for coastal management and conservation strategies.