黄土高原典型流域河川径流水文情势变化及其归因分析

[目的]分析黄土高原典型流域河川径流水文情势变化及其原因,为该区域水土保持与水资源高效利用提供科学支撑.[方法]选取渭河支流散渡河与无定河支流大理河为研究区,利用甘谷站和绥德站1965-2018年的气象水文资料,采用线性回归、Mann-Kendall检验、累积距平和双累积曲线法分析散渡河和大理河的径流变化特征及其驱动因...

Hydrologic Regime Change and Its Attribution Analysis of River Runoff in Typical Watershed on Loess Plateau

[Objective] The hydrologic regime change in typical watershed on Loess Plateau was studied, and its attribution analysis was carried out, in order to provide scientific support for soil and water conservation and efficient utilization of water resources in different regions of the Loess Plateau. [Methods] Sandu River (a tributary of Weihe River) and Dali River (a tributary of Wuding River) were selected as the study areas, and the traits in variations of streamflow and their driving factors from 1965 to 2018 were analyzed based on meteorological and hydrological data at Gangu and Suide hydrological stations by using the linear regression, Mann-Kendall test, accumulated anomaly, and double mass curve methods. The improved range of variability approach was employed to analyze the impact of the hydrological alterations in different river by soil and water conservation dominated by terracing and damming. [Results] The annual runoff showed significant decreasing trends(p<0.01) and the abrupt changes occurred in around 1990s in Sandu River and Dali River. The alteration degree of runoff in Sandu River was high (90.12%) and in Dali River was moderate (60.66%) calculated by the improved range of variability approach (RVA) method. Among 32 indicators of hydrologic alteration (IHA), the rise and fall rate of flow were affected most significantly. [Conclusion] In the Sandu River (dominated by terracing), both the magnitude of monthly median flow and the annual minimum flow decreased dramatically, timing of annual minimum flow delayed and duration of low pulses increased. In the Dali River (dominated by damming), the magnitude of monthly median flow depended on the seasonal alteration. The annual 1-day and 3-day minimum flow increased and frequency of low pulses declined.