基于GIS与RS的杨凌区土壤侵蚀时空变异性研究

土壤侵蚀是破坏黄土高原地区土地资源的重要因素,为深入了解黄土高原杨凌区水土流失现状,分析其土壤侵蚀空间分布规律及其时空变异性,基于GIS和RS技术,运用通用土壤流失方程(USLE)评估杨凌区侵蚀强度以及杨凌区土壤侵蚀的时空变异性。结果表明:杨凌区土壤侵蚀主要以微度侵蚀和轻度侵蚀为主,从2010—2014年间,土壤各级侵蚀强度所占比例基本稳定。分析土壤侵蚀与坡度和高程之间的关系表明,杨凌区15°的缓坡地以微度和轻度侵蚀为主,随着坡度的增加轻微度侵蚀减少,强烈、极强烈和剧烈侵蚀所占比例有所增加。各土壤侵蚀强度面积随着高程的增加呈先增大后减少的趋势,其峰值多分布在500～550m高程带。

Spatiotemporal Variability of Soil Erosion in Yangling District Based on GIS and RS

Soil erosion is an important factor in destroying land resources in the Loess Plateau. In order to understand the current situation of soil erosion in Yangling District of the Loess Plateau, the temporal and spatial distributions of soil erosion were analyzed using GIS and RS techniques. T General Soil Loss Equation (USLE) was also used to evaluate the erosion intensity and its temporal and spatial variability. The results showed that the soil erosion in Yangling District was mainly dominated by slightly erosion and mild erosion. From 2010 to 2014, the proportion of soil erosion intensity was basically stable. The relationships between soil erosion and slope and elevation indicated that the gentle slope of less than 15° in Yangling District was dominated by slight and light erosion. With the increases of slope, the slight erosion decreased, and the ratios of strong, extremely intense and severe erosions increased. The areas of soil erosion intensity showed a trend of decreasing with the increase of elevation, and the peaks were mostly distributed in the 500~550 m elevation zone.