Effects of topographic factors and land use on the spatial variability of topsoil nutrients in Hun-Tai river basin
Based on the GIS,statistics and geostatistics method,this study simulated the spatial distribution of surface soil nutrients,and explored the effects of topographic factors,land use types and their interaction in Hun-Tai river basin.The results indicated that elevation and slope were positively correlated with soil organic matter (SOM),total nitrogen (TN) and total phosphorus (TP) concentrations,while negatively correlated with total potassium (TK) concentration.Aspect had no significant effects on these soil nutrient properties.Forest and grassland had higher SOM and TP concentrations.Paddy field and cropland had higher TK concentration.Land use and topographic factors interactively affected soil nutrient properties.Higher SOM,TN and TP concentrations were distributed in the forest and grassland with higher elevation and greater slope.Topographic conditions and land use types can explain the spatial variability of soil nutrients in the study area.