River damming and drought affect water cycle dynamics in an ephemeral river based on stable isotopes: The Dagu River of North China

The flow regime and biogeochemical cycles are greatly affected by river damming drought, especially in ephemeral rivers. However, the combined effects have been rarely considered. This study, taking Dagu River Jiaodong Peninsula of North China as an example, investigated dynamic changes water cycle related to drought using stable isotopes for period 2018–2019. results indicated that significantly varied temporally spatially. temporal variations appeared be linked with those precipitation, but relationship between precipitation was damming, water-groundwater exchange potential pollution. Spatially, a single dam exhibited no significant effect on isotopes, accumulative impacts cascade dams resulted enrichment heavy towards downstream through increasing hydraulic residence time evaporation largely. inter-annual increased evaporative fractionation were highlighted their strong response 2019. changed dynamics further exacerbated shortage, which should thus fully considered resource management, regions water-limited heavily-regulated