The Simulated Experimental Research on the Fire Effects on Leymus chinensis Steppe.

With the method of controlled burning and simulated experiment, the fire effects and its action mechanism on Leymus chinensis Steppe in Inner Mongolia were researched. The results showed that the important reasons causing plant populations and community changes were the injury of fire to some plants' regeneration buds, the change of soil nitrogen content after burning and the remove of litters. Especially, the obvious increase of Leymus chinensis (community constructive species) related closely with the injury of fire to Stipa grandis (dominant species) and the increase of available nitrogen. The increase of available nitrogen and the raise of Leymus chinensis dominant degree may be the important reasons for the change of the species diversity in the community.