Characteristics of soil seed banks in grassland under fencing and grazing in Loess Plateau

Characteristics of soil seed bank, such as species composition, density and diversity in semiarid grassland on loess plateau under fencing and grazing conditions were investigated. The main inclusions were: 1) fencing greatly increased plant species and density of soil seed banks, palatable grass and perennial plant increased; 2) with the increasing soil depth, seeds decreased quickly; 3)Slope direction and position had a tremendous effect on soil seed banks. Density followed the order of southern slope northern slope; slope bottom medium top; 4) The results of the study indicated that the Margalef and the ShannonWiener diversity indexes of soil seed banks in fenced area were higher than enclosed grassland, while Pielou evenness indexes were higher in the latter.