The Study Of Liujiang Soil Nutrient Spatial Variation Characteristics

Soil nutrient status is the potential supply of soil nutrient ability, it’s an important indicator of soil nutrient content.Crop output level appear positive correlation relationship.In Liujiang county as the research object, this study aims is to master the county soil nutrient distribution rule. Firstly,we analyzed the Liujiang county sample data,mastered the values of soil nutrients,and analyzed data with normal distribution, related detection test, trend surface analysis, besides using GS+7.0 make the semivariance analysis, for picking out the optimal model,and in Arcgis10.0 making kriging interpolation, fig out the forecast.On this basis, analysising different soil types in the area,for guarantee the reasonable use of soil resources in the area.The results as follows:1.The average level of pH, total nitrogen, organic matter, available P, available K in the area is 5.983,1.686 g/kg,25.915 g/kg,31.364 mg/kg,86.663 mg/kg, generally pH partalized weakly acidic, total nitrogen in medium or low level, organic matter in the high level, available P and available potassium in low level.Nutrient data showed normally trend, its variable coefficient were 0.124,0.322,0.332,0.544,0.373, showed moderate variability, available P variability is the largest, pH variability is minimal.2. The evaluation model of pH, total nitrogen, organic matter, available K is Exponential model, the evaluation model of available P is the gaussian model.The pH, total nitrogen, organic matter, available P, available K,their nugget effect were 0.00172,0.499, 0.500,0.500,0.500, besides the pH showed out the strong spatial correlation, othes in the medium level.3.Soil pH, total nitrogen, organic matter in Liujiang county is higher in north lower in south, showed weaken trend from west to east.The organic matter, total nitrogen present a low trend from north to south,, and available P, available K is in low level.The pH, organic matter, total nitrogen, all of them showed standard error higher than the root mean square of prediction error.The Co-kriging results are better than the ordinary kriging.The pH, organic matter, total nitrogen, all of them showed standard error higher than the root mean square prediction error.4. Paddy soil, lime soil, new soil, chao soil in the area is particularly lacking,it’s better to increase all of them. Adjustmenting organic matter, total nitrogen,pH to a appropriate level.And, most of the sample point in the area are lacking of farmland facilities, soil nutrient loss a lot,it caused low yield crop cultivation.So,we should pay attention to hold the soil nutrition in farmland..