基于GIS的黄土丘陵区小流域土壤水分模拟

为了探讨黄土丘陵区桑塔小流域土壤水分的时空变化规律,在对定性数据如土地利用、坡向、坡位标准化处理的基础上,通过野外定点观测和室内处理,运用多元回归分析的方法,对土壤水分与地形湿度指数、土地利用类型系数和坡向系数进行相关性分析,建立了小流域土壤水分模型。结果表明:土壤水分模拟方程的复相关系数均在0.78以上,决定系数均在0.65~0.72,F统计量的P值远小于0.01,回归效果显著,能够模拟小流域土壤水分的时空分布。

Modeling Soil Moisture Based on GIS in Small Watershed of Loess Hilly Area

The spatial and temporal variation of soil moisture content in small watersheds of Loess hilly area was studied at Sangta watershed.Data standardization was used for quantitative data processing based on in-situ monitoring and lab analysis.The regression equations for each month from May to October were determined by taking monthly soil water contents as dependent variable and topographic wetness index,standardized slope aspects coefficient,land use coefficient and relative elevation coefficient as independent variables.Results showed that the multiple correlation coefficient R of regression equation were all above 0.78,coefficient of determination R2 ranged from 0.65 to 0.72,they all reached significant level(P<0.01).This study is useful to estimate soil water contents for regional soil erosion modeling.