Stable isotope composition in precipitation, river water, and groundwater was used to investigate the hydrological conditions in the Pihe River catchment of Southwest China. Significant seasonal isotopic variations exist in precipitation and river water, and there is 1-month delay in the river water response to precipitation. The river water is gradually enriched under the influence of evaporation. However, due to the influence of recharge from external water source, the evaporation ratios do not strictly increase with the flow distance. The seasonal isotopic values in groundwater fluctuate the least. River water supplies groundwater more than precipitation in dry season.

中文翻译：

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基于2H和18O时空分布的成都平原皮河流域水文条件识别

利用降水、河水和地下水中的稳定同位素组成研究了西南地区皮河流域的水文条件。降水和河水存在显着的季节性同位素变化，河水对降水的响应存在1个月的延迟。河水在蒸发作用下逐渐富集。但由于受外部水源补给的影响，蒸发率并没有严格随着流动距离的增加而增加。地下水中的季节性同位素值波动最小。河水在旱季供应地下水多于降水。