嫩江县土壤速效养分差异性分析

利用地统计学和GIS相结合的方法分析了嫩江县土壤速效养分空间异质性。采集土壤表层0~20 cm土样6 900个,采集土地利用类型为耕地,面积约35.6万hm2,进行化验分析和空间分析。结果表明:速效氮、速效磷、速效钾变异系数均在0.1~1.0,为中等变异;土壤速效磷的理论模型均为指数模型;速效氮和速效钾理论模型为球状模型;速效磷、速效钾的C0/(C0+C)分别为49.9%、50.2%,在25%~75%,变量具有中等空间相关性,而速效氮的C0/(C0+C)为79.5%,变量空间相关性较弱,表明土壤养分速效氮受随机性因子影响较大。

Difference Analysis on Nutrient Content of Soil in Nenjiang County

Geostatistics method and Geographic information systems (GIS) were introduced to study soil nutrient spatial heterogeneity in Nenjiang county of Heilongjiang province. 6 900 soil samples at the depth 0～20 cm were collected over 356 000 hm~2 farmland and measured with routine chemical methods and spatial analysis. The results showed that the soil available N, available P and available K were medium variation, and the coefficients of variation (CV) were all between 0.1 and 0.9; The theoretic model of available P is exponent; The theoretic models of available N and available K are spheroid; The ratios between C_0 and C_0+C of available P and available K were 49.9% and 50.2%, between 25% and 75%, respectively, which indicates the medium spatial correlation of these two nutrients; The ratios between C_0 and C_0+C of available N was 79.5%, it indicates weak spatial correlation, and available N was strongly affected by random factors.