Sun Bowen, Li Na, Wang Guoyu, Gao Xueping, Zhou Xushen, Kong Fanqing
State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation, Tianjin University, Tianjin, 300350, China.
State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation, Tianjin University, Tianjin, 300350, China.
J Environ Manage. 2024 Dec;372:123351. doi: 10.1016/j.jenvman.2024.123351. Epub 2024 Nov 16.
In aquatic ecosystems, phytoplankton, as key primary producers, are extremely sensitive to environmental changes. Artificial hydrological regulation, as a water resource management strategy, affects the water quality and ecological environment of the receiving water area. Particularly under multi-source replenishment conditions, the spatiotemporal nonlinear response of water quality poses a challenge to quantify the contribution of multi-source replenishment to the phytoplankton community succession in large lakes. For example, Baiyangdian Lake (BL) has implemented multi-source artificial hydrological regulation measures, including the diversion of the Yellow River into the BL (Xiaobai River), the South-to-North Water Diversion Project (Baigouyin River) and the replenishment of upstream reservoirs (Xiaoyi River, Bao River and Fu River). Physicochemical parameters and phytoplankton community data were surveyed from 2017 to 2020 in July (summer) and October (autumn). The ecological impacts of artificial hydrological regulation were investigated by quantifying the correlations between physicochemical parameters and phytoplankton communities and by quantifying the contribution of artificial hydrological regulation to key factors. The results show that under the artificial hydrological regulation, the phytoplankton community was still dominated by Chlorophyta and Cyanophyta, but the emergence of Xanthophyta and Chrysophyta indicated that the cleanliness of the water column was improved, and the biodiversity indicators showed a fluctuating upward trend, which suggested that the succession trend was favorable. Ammonia nitrogen (NH-N), total phosphorus (TP), and dissolved oxygen (DO) are the key factors affecting phytoplankton community succession in BL. The replenishment sources contribution index (RSCI) was used to characterize the spatiotemporal response of the key factors, and it was found that Fu River has the highest contribution of more than 30%, followed by Xiaoyi River with a contribution of more than 25%. The spatial distribution of RSCI shows that the area with high RSCI values (>0.9) of Fu River accounts for more than 50% of the total area, the area with high RSCI values (>0.9) of Xiaoyi River accounts for more than 35%. Under the comprehensive influence of the RSCI of each replenishment source, the phytoplankton biodiversity index of BL increased from north to south. This study provides basic support for BL in realizing the optimized artificial hydrological regulation strategy and enhancing the ecological restoration benefits in the receiving water area.
在水生生态系统中，浮游植物作为关键的初级生产者，对环境变化极为敏感。人工水文调控作为一种水资源管理策略，会影响受水区的水质和生态环境。特别是在多源补水条件下，水质的时空非线性响应给量化多源补水对大型湖泊浮游植物群落演替的贡献带来了挑战。例如，白洋淀实施了多源人工水文调控措施，包括引黄河水入淀（小白河）、南水北调工程（白沟引河）以及上游水库补水（孝义河、瀑河和府河）。于2017年至2020年的7月（夏季）和10月（秋季）对白洋淀的理化参数和浮游植物群落数据进行了调查。通过量化理化参数与浮游植物群落之间的相关性以及量化人工水文调控对关键因素的贡献，研究了人工水文调控的生态影响。结果表明，在人工水文调控下，浮游植物群落仍以绿藻门和蓝藻门为主，但黄藻门和金藻门的出现表明水柱清洁度有所提高，生物多样性指标呈波动上升趋势，这表明演替趋势向好。氨氮（NH-N）、总磷（TP）和溶解氧（DO）是影响白洋淀浮游植物群落演替的关键因素。采用补水来源贡献指数（RSCI）来表征关键因素的时空响应，发现府河的贡献最高，超过30%，其次是孝义河，贡献超过25%。RSCI的空间分布表明，府河RSCI值高（>0.9）的区域占总面积的50%以上，孝义河RSCI值高（>0.9）的区域占35%以上。在各补水来源RSCI的综合影响下，白洋淀浮游植物生物多样性指数由北向南增加。本研究为白洋淀实现优化的人工水文调控策略和提高受水区生态修复效益提供了基础支撑。
