Assessment of Arable Soil Quality in Tongchuan City

By correlation and Principle Component Analyze(PCA).Soil quality was assessed in 70 soil samples in Tongchuan city as coal base in Shaanxi province after analyzed soil organic matter,available nitrogen,available phosphate etc.The results showed as follows,the content of organic matter,available nitrogen and available phosphate were lower to supply plant growth,it is needed to improve soil nutrient levels by fertilization.Potassium was better than other chemical properties so that it is distinguish to fertilize different plots.Sulfur was enough for plants to grow because of higher available sulfur.The soil fertility information system can be an good index to indicate soil fertility levels by PCA.The soil samples with higher,middle and lower fertility account for 8.57%,54.28% and 37.14% respectively of total 70 samples,which indicated that the soil fertility level was lower status in Tongchuan region.The composite scores can be a better index to indicate soil fertility levels among soil samples tested.