The Fuzzy Comprehensive Evaluation of the Plant Communities Degree of Degradation of Prairie Meadows

The comprehensive evalution of the different plant communities diversity and degradation of Prairie Meadows. The result showed that, with the increase of grassland degradation degree, the composition of communities species was single, quantity gradually decreased, the change of species important value was obvious, the communities coverage, the communities height, ground production value was obvious decreasing trend; Plant communities a:diversity index, Margalef abundance, Simpson:advantage index Shanon-wiener:diversity index and Pielou:a verage index all have obvious decreasing, communities of similarity index has increasing trend. At the basis of indicator System fuzzy comprehensive evaluation review that the rang of indicating degree respectively:vegetation communities fence:1～0.7370,light grazing areas:0.7370～0.8117,moderate grazing areas:0.8117～0.4890,heavy grazing area:0.4890～0.