YRE-Cores(HHK1&2)-Bulk and molecular record

This study analyzed the centennial-scale sedimentary organic carbon (SOC) dynamics and phytoplankton community shifts in response to the anthropogenic interventions in the Yellow River Estuary (YRE). By analyzing bulk organic carbon (OC) parameters (TOC and δ13C), we reconstructed temporal trends of terrestrial and marine organic carbon (OCterr and OCmar) in the YRE and their relationship with riverine input and human interventions within the watershed. Molecular evidence (brassicasterol (B), dinosterol (D)) further demonstrated that the increased riverine nutrient fluxes, could directly enhance phytoplankton productivity. Moreover, changes in the B/(B+D) ratio indicated that the altered nutrient structure reshaped the community composition, with a decline in diatom dominance over the recent decades.

本研究剖析了黄河口（Yellow River Estuary, YRE）的百年尺度沉积有机碳（SOC）动态变化与浮游植物群落演替对人为干预的响应特征。通过解析体相有机碳（bulk organic carbon）参数——总有机碳（TOC）与碳同位素δ¹³C，本研究重建了黄河口陆源有机碳（OCterr）与海源有机碳（OCmar）的时间演化趋势，及其与流域内河流输入及人为干预的关联关系。分子标志物证据（菜籽甾醇（brassicasterol, B）、甲藻甾醇（dinosterol, D））进一步证实，河流营养盐通量的提升可直接增强浮游植物生产力。此外，B/(B+D)比值的变化表明，营养盐结构的改变重塑了浮游植物群落组成，近数十年来硅藻的优势度呈下降趋势。