In recent years, the rapid development of the population, agriculture, and tourism around Erhai Lake has caused increasing environmental problems, which have seriously affected the ecological status of the lake. This study analyzed changes in water volume and quality in Erhai Lake, based on statistical data from 2000 to 2019, combined with climate, land-use type, and socioeconomic data, as well as the influencing factors of water environmental changes in the Erhai Lake basin. The main conclusions include: the water storage of Erhai Lake increased by 3.8 × 10⁶ m³ year⁻¹, from 2000 to 2019. The monthly variation in water volume showed a trend of first decreasing and then increasing, in which it increased from August to December and decreased from January to July. The change in water volume was mainly affected by climate factors. From 2000 to 2019, the nitrogen concentration in Erhai Lake showed an increasing trend, and the changes in water quality were closely related to human activities. In the northern part of the basin, agricultural nonpoint source pollution was the main factor affecting water quality, while in the southern part of the basin, economic development, accelerated urbanization, and tourism were the main factors affecting water quality.

中文翻译：

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Er海水环境变化及其影响因素

近年来，Er海周围人口，农业和旅游业的迅猛发展引起了越来越多的环境问题，严重影响了该湖的生态状况。这项研究基于2000年至2019年的统计数据，结合气候，土地利用类型和社会经济数据，以及Er海流域水环境变化的影响因素，分析了water海的水量和水质变化。主要结论为：of海蓄水量增加3.8×10 ⁶ m ³年^-1，从2000年到2019年。水量的每月变化呈现出先减少后增加的趋势，从8月到12月增加，从1月到7月减少。水量的变化主要受气候因素影响。从2000年到2019年，Er海的氮浓度呈上升趋势，水质变化与人类活动密切相关。在流域北部，农业面源污染是影响水质的主要因素，而在流域南部，经济发展，城市化进程加快和旅游业是影响水质的主要因素。