基于氢氧同位素的黄土区场次降水水体补给转化关系研究OA北大核心CSTPCD

Ecological construction measures carried out in the Loess Plateau have changed the topography of the basin and affected the hydrological processes.In order to explore the influencing pathways,taking the Wangmaogou Basin,a typical small watershed in the loess area,was taken as the study area.The stratified soil samples,precipitation samples,surface water and shallow groundwater samples of dam land and terraced fields before and after precipitation were collected to analyze δD and δ18O in the water bodies by stable hydrogen and oxygen isotope technology.According to the analysis,the transmission and trans-formation relationship between precipitation,surface water,shallow groundwater and precipitation-soil wa-ter in the loess gully area was explored.The results showed that during the 20230423 period,the precipi-tation was 70.0 mm,the precipitation and surface water recharged shallow groundwater on the basin scale,with ratios of 27.62％and 72.38％,respectively.In the presence of dam land,the recharge rate of pre-cipitation to shallow groundwater increased by 31.90％in the process of water transmission from surface water to shallow groundwater.The evaporation loss during the transmission process of surface water to shal-low groundwater was 1％-13％,which increased with the increase of the transmission distance.The deep soil water of the dam land was more susceptible to precipitation recharge than that of the terraced fields.The vertical recharge rate of soil water from 0-60 cm to 60-100 cm soil layer in dam land(48.11％)was less than that of soil water from 0-40 cm to 40-100 cm soil layer in terraced fields(55.11％).This study can shed some light on the impact of ecological construction and management on the hydrologi-cal process of the basin and the protection of the regional ecological environment in the Loess Plateau.