黄河中游多沙粗沙区流域坡面水保措施变化特征

选用Landsat TM、环境星CCD、SPOT4 和资源三号卫星影像等多源地学数据，通过人机交互式解译和修订土地利用与梯田数据，提出用相邻图幅递进回归分析法消除NDVI时相差异后反演植被盖度，构建起退耕还林还草面积比例、植被盖度均值变化量和有效梯田累计保存面积比例3 个坡面特征变化指示参数后，运用综合聚类分析和多要素贡献率模型研究黄河中游多沙粗沙区的流域坡面水保措施变化特征。结果表明：（1） 1998-2010 年间研究区内流域坡面水保措施变化显著，平均退耕还林还草面积比例为5.55%，平均林草植被盖度均值增加20.63%，平均有效梯田累计保存面积比例达6.25%；（2） 多要素水保措施变化共同作用下的流域坡面变化特征主要有7 种类型，即植被盖度变化主导型、植被—土地变化主导型、土地—植被变化主导型、植被—梯田变化主导型、梯田—植被变化主导型、梯田面积变化主导型和多要素变化共同主导型；（3） 不同类型的空间分布存在一定的地貌背景差异，后续研究应结合流域坡面变化特征及其地貌格局来优化配置水保措施，并合理估计水沙模型模拟的敏感性参数。

Characteristics of soil and water conservation measures change in the watershed slope of the middle Yellow River Basin

This study chose multi-source remote sensing images to extract spatial information, and designed three parameters. It applied integrated cluster analysis and factors contribution model to research the variation of watershed slope in the rich and coarse sediment area of the middle Yellow River Basin. Conclusions can be drawn as follows. (1) The watershed slope characteristics of the study area have changed from 1998 to 2010, including a great increment of forest, grassland and terrace area, and vegetation coverage has restored obviously. (2) There are 7 types of watershed slope variation, which are the result of changes of soil and water conservation measures. According to contribution rates, they are named as type-1 dominated by vegetation coverage change, type-2 by vegetation coverage and land use change, type-3 by land use and vegetation coverage change, type-4 by vegetation coverage and terrace area change, type-5 by terrace area and vegetation coverage change, type-6 by terrace area change and type-7 by multi-source factors. (3) The spatial distribution of each type has its unique geomorphic background, and the future work should take the watershed slope characteristics and geomorphic patterns into account, and should assess the sensitivity of different hydrological and sediment yield models rationally.