气候变化及生态建设措施对宁夏典型入黄流域径流变化影响

为分析气候变化及植被和淤地坝等生态建设措施对径流变化的影响，选取宁夏典型入黄流域清水河和苦水河为研究对象，采用Pettitt突变方法分析研究流域气象水文和生态建设措施等要素的变异点，基于Budyko理论，通过建立水热耦合控制参数与生态建设措施的多元线性回归方程，构建耦合生态建设措施下的降水—径流模型，并对模型进行适用性评估，采用弹性系数法，量化不同生态建设措施对径流变化的贡献率。结果表明：研究流域径流均呈减小趋势，且年径流突变均发生在2000年；水热耦合控制参数与NDVI和淤地坝指数呈显著的正相关关系，引入NDVI和淤地坝指数构建的降水—径流模型模拟值接近实测值；清水河流域生态建设措施实施对径流减少的贡献率高达78.25%,其中，植被和淤地坝对径流减少贡献率分别为23.11%,46.50%,生态建设措施对径流的影响远大于气候变化对径流产生的影响。苦水河流域降水对径流减少贡献率可达47.30%,生态建设措施对苦水河径流减少贡献率为59.57%,植被和淤地坝贡献率分别为18.57%,13.96%,其他生态建设措施对径流减少贡献率为27.04%。生态建设是引起宁夏入黄流域径流变化的主要驱动因...

Impacts of Climate Change and Ecological Construction Measures on Runoff Changes in Yellow River Tributaries of Ningxia Section

In order to analyze the impact of climate change and ecological construction measures such as vegetation and silt dams on runoff changes, the Qingshui River and Kushui River, typical watersheds into the Yellow River in Ningxia, were selected as the research objects. The Pettitt mutation method were used to detect the change points of meteorological, hydrological, and ecological construction measure series, and the multivariate linear regression equations between the land surface parameter and ecological construction measures were constructed, rainfall runoff model coupled ecological construction measures was derived based on the Budyko theory, the applicability of the model was evaluated, and the elastic coefficient method was used to quantify the contribution rate of different ecological construction measures to runoff changes. The results indicated that the runoffs in the study watersheds showed decreasing trends, and the change points of annual runoff occurred around 2000. The land surface parameters had significant positive correlations with the NDVI and silt dam index, and the simulated values from the rainfall-runoff model constructed by the introduction of the NDVI and the silt dam index are close to the observed values. The contribution rate of ecological construction measures to the reduction of runoff was as high as 78.5% in the Qingshui River basin, and vegetation and silt dams contributed 23.11% and 46.50%, respectively. The impact of ecological construction measures on runoff was much greater than that of climate change. The contribution rate of rainfall to runoff reduction in the Kushui River Basin can reach 47.30%, and the contribution rate of ecological construction measures was 59.57%, with vegetation and silt dams contributing 18.57% and 13.96% respectively, while the contribution rate of other ecological construction measures to the reduction of runoff was 27.04%. Ecological construction was the main driving factor causing changes in runoff in the Ningxia Yellow River Basin. The research results can provide theoretical support for optimizing the layout of ecological construction in Ningxia.