Daphniid zooplankton assemblage shifts in response to eutrophication and metal contamination during the Anthropocene

Human activities during the Anthropocene result in habitat degradation that has been associated with biodiversity loss and taxonomic homogenization of ecological communities. Here we estimated effects of eutrophication and heavy metal contamination, separately and in combination, in explaining zooplankton species composition during the past 125–145 years using analysis of daphniid diapausing egg banks from four lakes in the northeastern USA. We then examined how these community shifts influenced patterns of diversity and homogenization. Analysis of past lake production (via subfossil pigments) and metal contamination (via sedimentary metals) demonstrated that eutrophication alone (19–39%) and in combination with metal pollution (17–54%) explained 36–79% of historical variation in daphniid species relative abundances in heavily fertilized lakes. In contrast, metal pollution alone explained the majority (72%) of historical variation in daphniid assemblages at the oligotrophic site. Severa...人类世时期的人类活动引发生境退化，该现象与生物多样性丧失及生态群落的分类群均质化密切相关。本研究以美国东北部四个湖泊的溞类（Daphniidae）滞育卵库为分析材料，定量评估了富营养化、重金属污染及其复合作用对过去125至145年间浮游动物物种组成的解释效力。随后，本研究进一步探讨了这些群落结构变化对生物多样性及均质化模式的影响。通过亚化石色素分析重建湖泊历史初级生产力、并通过沉积金属分析评估重金属污染程度的结果显示：在受高强度人为施肥影响的湖泊中，单一富营养化即可解释36%至79%的溞类物种相对丰度历史变异，其中单独贡献为19%至39%，与重金属污染复合作用的贡献为17%至54%。与之形成鲜明对比的是，在贫营养湖泊样点中，单一重金属污染即可解释72%的溞类群落组成历史变异。多项...