伊犁绢蒿荒漠草地土壤养分和植被指数的空间异质性研究

目的]土壤养分与植被分布格局之间的关系.方法]应用地统计学方法,研究伊犁绢蒿(Seriphidium transiliense)荒漠草地土壤养分与植被指数的空间异质性.结果](1)绢蒿荒漠土壤碱解氮、速效钾含量空间自相关性较差,而有机质、全磷、速效磷、全钾、全氮、植被指数(NDVI)自相关性较好.(2)通过半方差分析各项目都能用很好的模型来拟合,有机质符合线形模型,全钾、全磷、全氮、速效磷、碱解氮、速效钾和植被指数均符合高斯模型.(3)土壤养分元素和植被指数的变程在23.58～110 m,相差比较大.结论]通过普通克立格插值,绘制了植被指数与土壤有机质和土壤养分的等值线分布图.对绢蒿蒿类荒漠草地土壤养分与植被指数空间异质性分析有助于分析植被指数的空间异质化程度与土壤元素伊犁(OM,N、P、K)空间异质化的相关性.

Study of Spatial Heterogeneity of Vegetation Index and Soil Nutrients of Seriphidium Transiliense Desert Grassland

Objective and Method]With the aid of Geostatistics, the spatial distribution of soil properties in Artemisia desert grassland of purple soil was described and illustrated and the rational points in sampling of soil in the sloping land were further ascertained. Result]The results indicated that(1): the spatial correlation of total phosphorus, available phosphorus, potassium, nitrogen, vegetation index (NDVI)was high, so their variabilities were mainly affected by structural factors. Moreover, the spatial correlation of available K and available N was low. (2) In the semi-variance analysis, every object could fit the models perfectly.Organic matter fitted the linear model, total K,total N,total phosphorus,available P,available N,available K and NDVI could be explained by the Gaussian model.(3) The ranges of soil nutrients were 23.58 m-110 m. The spatial variability of all soil nutrients were mainly produced by structural factors and random factors. Based on the semi-variance and Kriging interpolation method, the isolines of soil nutrients were mapped. The spatial distributions of soil organic matter, total-N and available phosphorus were similar to each other,while the available N and available K were clearly different. Conclusion]The analysis of soil nutrients and vegetation indexes help to analyze the correlation between the spatial heterogeneity of vegetation index and the degree of soil elements (OM, N, P, K) spatial heterogeneity of relevance.