The changes of runoff in the middle reaches of the Yellow River basin of China have received considerable attention owing to their sharply decline during recent decades. In this paper, the impacts of rainfall characteristics and land use and cover change on water yields in the Jingle sub-basin of the middle reaches of the Yellow River basin were investigated using a combination of statistical analysis and hydrological simulations. The Levenberg Marquardt and Analysis of Variance methods were used to construct multivariate, nonlinear, model equations between runoff coefficient and rainfall intensity and vegetation coverage. The land use changes from 1971 to 2017 were ascertained using transition matrix analysis. The impact of land use on water yields was estimated using the M-EIES hydrological model. The results show that the runoff during flood season (July to September) decreased significantly after 2000, whereas slightly decreasing trend was detected for precipitation. Furthermore, there were increase in short, intense, rainfall events after 2000 and this rainfall events were more conducive to flood generation. The “Grain for Green” project was carried out in 1999, and the land use in the middle reaches of the Yellow River improved significantly, which make the vegetation coverage (V_c) of the Jingle sub-basin increased by 13%. When V_c approaches 48%, the runoff coefficient decreased to the lowest, and the vegetation conditions have the greatest effect on reducing runoff. Both land use and climate can change the water yield in the basin, but for areas where land use has significantly improved, the impact of land use change on water yield plays a dominant role. The results acquired in this study provide a useful reference for water resources planning and soil and water conservation in the erodible areas of the middle reaches of the Yellow River basin.

中文翻译：

---

黄河流域降雨特征和土地利用/覆盖变化对径流的影响。

黄河流域中游的径流变化由于近几十年来的急剧下降而备受关注。本文采用统计分析与水文模拟相结合的方法，研究了黄河中游静乐子流域降雨特征，土地利用和覆盖变化对水产量的影响。Levenberg Marquardt和方差分析方法被用来构建径流系数与降雨强度和植被覆盖率之间的多元非线性模型方程。使用过渡矩阵分析确定了1971年至2017年的土地利用变化。使用M-EIES估算土地使用对水产量的影响水文模型。结果表明，2000年以后，汛期（7月至9月）径流明显减少，而降水量则略有下降。此外，2000年以后短时强降雨事件增多，这种降雨事件更有利于洪水的产生。1999年开展了“绿色换粮”工程，黄河中游地区土地利用状况得到明显改善，使静乐子流域的植被覆盖率（V _c）增加了13％。当V _c接近48％，径流系数降低到最低，植被条件对减少径流的影响最大。土地利用和气候都可以改变流域的水产量，但是对于土地利用得到显着改善的地区，土地利用变化对水产量的影响起着主导作用。研究结果为黄河流域中游易蚀区水资源规划和水土保持提供了有益的参考。