Abstract: Soil nutrient is the material guarantee of plant growth. Topography and human activities will affect the spatial distribution of soil characters. Taking Maoshan watershed in the black soil region of Northeast China as an example, this paper analyzed the spatial characteristics of soil nutrients by using GIS technology and geostatistics method, and also explored the effects of topographic factors, land use types and their interaction. The results showed that: ①The distribution of soil nutrients in Maoshan watershed accorded with the normal distribution. The variation coefficients of soil organic matter, alkaline hydrolysis nitrogen, available phosphorus and available potassium were 1734% ～ 4081%. ②The spatial distribution of soil nutrients increased from northwest to southeast, and the content of soil nutrients in the middle of the basin was higher than that in the east and west. ③Elevation and slope factors were negatively correlated with soil organic matter, alkaline hydrolysis nitrogen, available phosphorus and available potassium. Soil nutrients had no significant correlations with slope aspect. ④Elevation factors and land use types interactively affected soil nutrient properties. Slope, aspect factors and land use types interactively had no significant effects on these soil nutrient properties.

Key words: soil nutrient, topographic factors, land use, spatial variability

摘要： 土壤养分是植物生长的物质保障，地形及人类活动均会影响土壤性状的空间分布。以东北黑土区冒山小流域为例，将GIS技术与地统计学方法相结合，对土壤养分的空间分布特征进行分析，并探讨了地形因子、土地利用方式及其交互作用对土壤养分空间变异的影响。结果表明：①冒山小流域土壤养分分布符合正态分布，土壤有机质、碱解氮、速效磷和速效钾变异系数为1734%～4081%。②土壤养分空间分布总体呈现由西北向东南递增，在流域中间位置较东西两侧含量偏高。③海拔因子和坡度因子均与土壤有机质、碱解氮、速效磷和速效钾呈显著负相关，坡向因子与表层土壤养分含量不存在显著相关关系。④海拔因子与土地利用的交互作用对表层土壤养分含量影响显著，坡度因子和坡向因子与土地利用交互作用对表层土壤养分没有显著影响。

关键词: 土壤养分, 地形因子, 土地利用, 空间变异性