Study On Community Species Composition And Diversity Of Larix Gmelinii Burned Area In Mohe

Fire is the main disturbing factor of forest community in Mohe,variation of species composition in post-fire forest restoration process is one of the important contents of restoration ecology research.The method of community survey is used in this study,investigating plant sample plots in 30 natural Larix gmelinii burned area with different forest fire intensity disturbing and different restoration periods in Mohe area,analyzing the species composition and diversity,which can provide theoretical basis for vegetation restoration of the area.The main results of this paper are as follows:In the process of low intensity burned area recovery,Larix gmelinii is always the dominant tree species in tree layer,the tree layer density doesn't change significantly,the canopy has basically recovered in 30 years.The coverage of shrub layer decreases gradually,diversity index changes not prominently,The coverage of herb layer increases gradually,diversity index increases gradually.Restoration degree show:30a>20a>10a.The community has approached the unbuned community in 30 years.In the process of medium intensity burned area recovery,Larix gmelinii is always the dominant tree species in tree layer,the community density changes greatly,the canopy gradually recover.The coverage of shrub layer decreases gradually,diversity index changes significantly.The coverage of herb layer increases gradually,diversity index increases gradually.Restoration degree show:30a>20a>10a.There are significant differences in species composition between community and non-burned plots in 30a.In the process of high intensity burned area recovery,broadleaf trees are always the dominant tree species in tree layer,tree DBH and tree height increase significantly,the community density increases rapidly,canopy recover rapidly.The coverage of shrub layer decreases gradually,diversity index changes significantly.The coverage of herb layer increases gradually,diversity index increases gradually.Restoration degree also show:30a>20a>10a,but the secondary succession of communities is different from that of the first two types of burned area.