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运用GIS与地统计学相结合的方法,在村级尺度下研究了渝东北丘陵区农田土壤碱解氮、速效磷的空间变异性。结果表明:在村级尺度下土壤碱解氮、速效磷含量都具有中等程度变异,变异系数分别为40.27%和64.21%。土壤碱解氮半方差函数最佳理论模型为高斯模型,且具有强烈的空间相关性,C0/(C0+C)值为14.5%,空间相关距离为61 m;速效磷以指数模型模拟最好,具有中等程度的空间相关性,C0/(C0+C)值为45.0%,空间相关距离为47 m。土壤碱解氮在东西方向上表现出各向异性,与地形表现出很好的一致性;土壤速效磷在东西、南北方向上都有明显的趋势特征,表现出各向异性。
Using the method of GIS and geostatistics, the spatial variability of soil available nitrogen and available phosphorus in the hilly area of northeast Chongqing were studied at the village scale. The results showed that there was a moderate degree of variation of soil available nitrogen and available phosphorus at the village scale with the coefficients of variation of 40.27% and 64.21% respectively. The best theoretical model of soil available nitrogen for semivariogram function was Gaussian model with strong spatial correlation, C0 / (C0 + C) value was 14.5% and spatial correlation distance was 61 m. Available phosphorus was best simulated by exponential model , With a moderate degree of spatial correlation with a C0 / (C0 + C) value of 45.0% and a spatially dependent distance of 47 m. Soil available nitrogen showed anisotropy in the east-west direction and showed good consistency with the topography. Available phosphorus in soil showed obvious trend characteristics in east, west and north-south directions and showed anisotropy.