Studies On Seed Plants Diversity And Human-induced Vegetation Restoration In Duolun County

Duolun County situated in the south-east of Xilin Gol league, it is also an important part of north stepped in China. After the 1990s, with the increasing of population and livestock, it has suffered desertification. Now it is one of sources of sandstorm.This thesis research on the characteristics of compact of floristic elements and the relation ship of plant community in the degenerated grassland and environment, the effect of manpower restoration to sand and pasture that is closed and the effect to plant diversity under the different plantation in Duolun county. The intention is to provide scienced proof for the protection of plant diversity and vegetation restoration in Duolun County. Some conclusions are made in the thesis displayed below:(1) The flora of Duolun County consists of 465 species belonging to 75 families and 249 genera, respectivty proportion is 21.1% and 64.1 and 37.5 of the all wild seed plants in Inner Mongolia. Focusing the research on plant distribution, we will know that the temperate zone is dominant in Duolun flora. The composition diversity is complex and passageway at the same time there are mang age-old composition but lacking of endemic element.(2) Eight types of community can be identified with the DCCA method and showed by plant diversity Return to the analysis.it prove that there are closed connection between species diversity and its environment factors.(3) In this field the sample area is about 10 m~2 is better. Human-induced Vegetation Restoration is concluded that not only controlled soil Erosion but also increased species richness in the representative area.(4) The experiment for closing the degenerated rangeland in Duolun county Results showed that, once degenerated rangeland was closed, the coverage and the hight and the forage production and the root biomass of the rangeland increased evidently, and the vegetation recovered rapidly. If recovered vegetation continued to be closed, the results were not evident.So reasonable close period for degenerated rangeland is about 5 years in Hunshandake Sandyland.(5) The grassland areas construction plantations would not result in the biodiversity and herbages biomass remarkable decrease; it have something to do with plantations species; the central plantations herbaceous species variety compares edge 's variety greatly.