三工河流域下游绿洲土壤微量元素有效含量空间变异特征

土壤微量元素空间分布特征是反映特定地区环境状况的一个重要因素。基于GIS技术，通过地统计学方法研究了天山北坡三工河流域冲积平原型绿洲土壤表层微量元素B、Mn、Zn、Fe及Cu等有效含量的空间变异特征。结果表明：①土壤微量元素B、Mn、Zn、Fe和Cu具有强烈的空间自相关性，自相关范围在520～3 970 m内变化，其中Zn和Fe的自相关性尺度相对较大，而B的自相关性尺度最小。②土壤微量元素均具有各向异性，其中在0°方向上变异最大。整体来看，研究区土壤有效B、Fe和Cu具有较强的各向异性，而有效Mn和Zn各向异性相对较弱。③采用Kriging和IDW两种插值方法分析研究区土壤微量元素的空间格局，结果表明,土壤微量元素呈现出明显的片状和斑块状分布特点。研究区中西部有效B含量较高，有效Mn、Zn、Fe和Cu含量均较低。

Spatial Variability of Oasis Soil Available Trace Elements in the Lower Reaches of Sangong River Watershed, North Xinjiang

Geostatistics combined with GIS was applied to analyze the spatial variability of oasis soils available trace elements in alluvial plain of Sangong river watershed, North Xinjiang. The results show that: (1)Soil available B, Mn, Zn, Fe and Cu present strong spatial correlation, and the ranges of autocorrelation are around 520~3 970 m; the autocorrelation ranges of available Zn and Fe are larger, and that of available Cu is smaller. (2)All available trace elements express anisotropy, showing the largest variability along the direction of 0°. In general, the anisotropy of B, Fe and Cu are stronger, and that of Mn and Zn are weaker. (3)The Kriging and IDW interpolation methods are applied to describe and analyze the spatial distribution of available trace elements. Results show that available trace elements appear spot or patch distribution pattern in the study area. As a whole, content of available B is higher and that of the other four are lower in the midwest of this area.