The Element Content Characteristics of Main Species in Leymus Chinensis Grassland in Inner Mongolia, China

The absorption and utilization of plant nutrients is the key process of ecosystem material cycle, and it's also a important issue for the restoration and reconstruction of degraded ecosystem. To explore the absorption and utilization regularities on nutrients in the grassland ecosystem plants, the characteristics of 10 elements in 11 main species such as Leymus Chinensis, Agropyron c ristatum, Stipa grandis, Achnatherum. sibirica, Cymbaria dahurica., Koeleria cristata, etc., collected in the Xilin River Basin, were investigated. The results showed that:(1) The contents of plant elements in the study area belongs to(K) (Ca) (Mg) type. The coefficients of variation of elements contents were less than 1, indicated there were no obvious differences among plant elements of different species.(2) Correlation analysis among plant elements indicated N and K, N and Mg, P and K, P and Mg, Ca and Mg, Fe and Cu were of markedly positive correlation(P≤0.01), but C and Fe, C and Cu were of negative correlation; N and P, N and Ca, K and Mg were statistically significant(P≤0.05).(3) Gramineous plants have lower N、P、K、Ca and higher Fe, Cu content, but Mn, Zn, P, Mg, Ca, K, N, C in non-gramineous plants were higher, while Ca, K, Mg were statistically most significant difference(P≤0.01), as well as N(P≤0.05). And(4) we used principal component analysis to evaluate the level of plant nutrients, as a result, Cymbaria dahurica L.,Koeleria cristata and Potentilla tanacetiflolia had higher nutrients content, so they had a better ability to absorb nutrients.