关键词: 无机磷分级, 无机磷分级

Abstract: To understand the distribution and change of soil nutrients in Xilinguole grassland, we analyzed the data of soil nutrients between 2006 and 2010 using the methods of mathematical statistics such as monadic linear regression, linear tendency estimates and correlation analysis, ect. Results showed that the content of organic matter, total N, total P and total K in soil were 22.371 g/kg, 1.053 g/kg, 0.36 g/kg and 23.737 g/kg, and decreased with increasing layer depth along 0-5, 5-10, 10-20, 20-30 cm, which decline rate were -0.361, -0.031, -0.004, -0.051 (g/kg)/cm, and also had some correlation in organic matter, total N, total P and total K. The content of organic matter has been a significant rise from year to year, and the correlation coefficient between content and years was -0.8087 and passed 5% level of significance. There had otherwise been a notable downtrend with total K and the correlation coefficient was -0.903 and passed 5% level of significance. Change trend of total N and total P were not obvious and the rate were 0.015, 0.012 (g/kg)/year. In general, soil nutrients were some different in different types of grassland.