Analysis On The Soil Nutrient Change Of Artemisia Desert Grassland In Different Degraded Stages

The study is to research the change of soil factors under different degraded succession of non-degradation, mid-degradation, heavy-degradation and over-degradation on Artemisia desert in northern slope middle part of Tianshan mountain, to analyze the rules of soil nutrient, to filter the factors of soil inspect by the method of PCA, and to analyze the relations between vegetation and soil by the methods of cluster analysis and relevancy. The results show:1 Under the different degraded succession, the soil machinery composition changes gradually roughness. The contents of pH, total salt, organic matter and total nitrogen change unremarkably under non-degradation, mid-degradation, heavy-degradation, but there are remarkable changes under over-degradation. The contents of total phosphorous and total potassium are rather stabilization under the different degraded succession. The contents of available nitrogen change remarkably with the degraded succession. The changes of available phosphorous and available potassium are not obvious under non-degradation, mid-degradation, heavy-degradation, but increase under over-degradation.2 In section plane of soil, the content of bulk increases with the layer adding, but content of pH changes unremarkably. The content of total salt is high in 10～20cm than 20～30cm. The contents of organic matter, total nitrogen, total phosphorous, total potassium, available nitrogen, available phosphorous and available potassium are higher in 0～10cm than others.3 Through the method of PCA, combining correlation analysis and soil factors'stability correspond to environment, the factors are filtered. Finally the total nitrogen, the organic matter, the total salt is considered as the soil monitor target.4 Contrasting the degraded stage divided by the vegetation with the degraded stage divided by the soil nutrient, the results indicate when vegetation reach over-degradation, but the soil nutrients are still keep on stability. And applying the method of relevancy show that there are positive correlations between the bulk, organic matter and the yield, cover degree, density of vegetation.