Singh Reeta, Kayastha Sadhana Pradhanang, Pandey Vishnu Prasad
Central Department of Environmental Science, Tribhuvan University, Nepal.
Department of Civil Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University, Nepal; Center for Water Resources Studies, Institute of Engineering, Tribhuvan University, Nepal.
Environ Res. 2022 Dec;215(Pt 1):114104. doi: 10.1016/j.envres.2022.114104. Epub 2022 Aug 31.
Climate change alters the river flow regimes causing significant changes in the structure and function of an aquatic ecosystem, ultimately affecting river health. This study applied a customized framework consisting of 1-index, 4-components, 6-indicators, and 43-metrics, to assess river health for two seasons and future periods, in the Marshyangdi Watershed, Nepal. Hydrological, water quality, biological and physical conditions were assessed using simulated results from a hydrological model, physiochemical analysis of water samples, macroinvertebrates assemblages analysis, and physical habitat condition assessment, respectively. Climate change impact on river health was assessed based on projected climate (precipitation and temperature) based on regional climate models under representative concentration pathways (RCP) 4.5 and 8.5 scenarios until the mid-century. Results showed moderate river health condition in both the seasons and it's deterioration for future scenarios and periods. It reveals the need to formulate appropriate measures for the conservation of the river health.
气候变化改变了河流流量模式，导致水生生态系统的结构和功能发生显著变化，最终影响河流健康状况。本研究应用了一个定制框架，该框架由1个指数、4个组成部分、6个指标和43个度量标准组成，用于评估尼泊尔马斯扬迪河流域两个季节及未来时期的河流健康状况。分别使用水文模型的模拟结果、水样的理化分析、大型无脊椎动物群落分析和物理栖息地状况评估来评估水文、水质、生物和物理条件。基于区域气候模型在代表性浓度路径（RCP）4.5和8.5情景下直至本世纪中叶的预测气候（降水和温度），评估气候变化对河流健康的影响。结果表明，两个季节的河流健康状况均为中等，且未来情景和时期会出现恶化。这表明需要制定适当措施来保护河流健康。
