Relationship between species diversity and soil factors of alpine grasslands in north Tibet

Relationships between species diversity and the soil factors of alpine grassland in north Tibet were studied.Correlation and regression analysis were used to study the relationships between 3 diversity indexes and 7 soil factors.Results indicated that community composition gradually tends to simplify from alpine grassland to alpine desert.Soil organic matter,total nitrogen,available nitrogen and total phosphorus were positive correlative to species diversity and richness significantly(p0.01);Relationships between evenness index and all of the soil factors were not reach significant level.Stepwise regression analysis showed that soil organic matter and total nitrogen had great impact on species diversity.