中文摘要：

借助地理信息系统，利用地统计学中的半变量变异函数研究了巢湖北岸六岔河流域多水塘一沟渠系统中的土壤养分空间变异特征。研究结果表明：土壤中有机物（OM）、总氮（TN）、总磷（TP）、氨态氮（NH4-N）、硝态氮（NO3-N）的空间变异函数理论模型均符合球状模型，总磷、氨态氮、有机物空间异质性中的结构性变异大于随机变异；总氮、硝态氮的结构性变异小于随机变异。有机物、总氮、总磷、氨态氮、硝态氮等空间自相关范围具有明显的差异性，变化范围为123．9-517．36m，呈现出氨态氮〉硝态氮〉总氮〉有机物〉总磷，变化范围相差4倍左右，上述差异主要与养分特性、土地利用以及多水塘一沟渠系统景观等因素关系密切。

英文摘要：

The agriculture nonpoint source pollution is the major influencing factor to lake eutrophication in the middle and lower reach of Changjiang River. Understanding of the distribution of soil nutrients at the field and catchment scale is of importance for improving agricultural management to control agriculture non- point source pollution. Based on the spatial analysis function of GIS, spatial heterogeneity of soil nutrients in a muhipond-system of the Liuchahe watershed was studied using semivariogram of geostatistics. Theoreti- cal semivariogram models of soll organic matter（OM）, total N（TN）, nitrate（NO3-N）, ammoniacal nitrogen （NH4-N） and total P（TP） were accord with spherical model. The ratio of random variance （nugget） to total variance was low, these values were 28.8% for TP, 73.2% for TN, 44.0% for NH4-N, 77.35% for NO3-N, 23.9% for OM, respectively, The significant differences in ranges of these five soil nutrients were found. The TN had the highest values of variation, the next is TP, while the NH4-N and NO3-N were the lowest. These differences in ranges can be explained by the particular properties of soil nutrients, land use patterns and muhipond-system landscape.