Abstract: Plant diversity of ecotone community between forest and marsh in Changbai Mountain was studied using whit net-check method throughout the ecotone , and the plant diversity , edge effects and their relation with ecotone enviromental gradient in two primary types of ecotone was also investigated , in order to reveal the characteristics and their forming mechanism and provide the theoretical foundation for the conversation and maintainance of plant diversity.

The conclusion is that plant diversity of ecotone community between forest and marsh increases gradually along with the ecotone enviorment gradient in the Changbai Mountain. The mature community processes the highest diversity in the ecotone. It is also higher than that in the corresponding typical forest community. This kind of ecotone community is abundant in species because ecotones contain marsh plants , forest plants and ecotone’s dominant species. The amount of some dominant species populations are five times as many as in the forest . So that edge effects exist in this ecotone. These characterristics of ecotone between forest and marsh are related closely with the ecological special properties of plants and the ecotone environmental gradient .