This research aims to decipher the patterns and mechanisms of surface water recharge during the rainy season in plateau mountain-lake region.Based on the stable hydrogen and oxygen isotope data of multiple water bodies collected in the Erhai Lake Basin from July to August 2022,and using Bayesian mixing models and remote sensing technology,the study quantifies the sources and proportions of surface water recharge and explores water body transformation mechanisms.The results indicate that:(1)Precipitation in the Erhai Lake Basin during the rainy season is influenced by evaporation and monsoon climate,resulting in hydrogen and oxygen isotope values that are more negative compared to groundwater and surface water.Groundwater δD and δ18O indicate that in areas of high altitude and high water richness,the hydrogen and oxygen isotope values of groundwater are more negative,while d-excess values reveal evaporation differences among different aquifer groups.The hydrogen and oxygen isotope values of surface water gradually become more positive as the water flows from inflowing rivers through Erhai Lake to outflowing rivers,with the isotope values on the eastern slope and southern region of Cangshan Mountain being more positive compared to the northern region.For the eastern slope of Cangshan Mountain,the midstream area shows the most significant evaporation.(2)The spatial pattern of surface water recharge sources between Cangshan Mountain and Erhai Lake shows that surface water contributes the most to its downstream mixed water bodies.The contribution rate of precipitation and surface water in each river section between Cangshan Mountain and Erhai Lake is shown as follows:the contribution rate of precipitation and surface water in the river section above the mountain outlets is smaller than that in the river section below the mountain outlets;while the contribution rate of groundwater is vice versa.(3)Along the river flow direction,the spatial pattern of surface water recharge sources is jointly influenced by topography,geological conditions,surface cover,and water vapor characteristics.Areas with good vegetation cover,high surface temperatures,and high actual evapotranspiration receive more precipitation recharge;areas with relatively poor vegetation cover receive more surface water recharge and the contribution rate of groundwater to surface water depends on the type of aquifer groups.
关键词
氢氧稳定同位素/地表水补给来源/苍山洱海/高原湖泊/遥感技术/贝叶斯混合模型
Key words
hydrogen and oxygen stable isotope/surface water recharge sources/Cangshan Mountain-Erhai Lake region/plateau lakes/remote sensing technology/Bayesian mixing model
维普
万方数据