Wetland pattern change and affecting factors in the burned area of northern Great Hing′an mountains

The catastrophic forest fire on the northern slope of Great Hing'an Mountains in 1987 greatly affects the ecological environment. Wetland,as one of the important attributes,is very sensitive to the environment change. The Yuying and Fendou farms administered by Tuqiang forestry bureau,one of the mainly burned area in 1987 fire,are selected as the study area to reveal the wetland pattern change and the restoration of the regulating capacity of forest hydrology post-fire with GIS software. The results show that the total area of wetland increases by 77.56% with convergence tendency compared with that of pre-fire, and the average regulating capacity of forest hydrology restores a lot,but the area of high regulating capacity of forest hydrology decreases. The regulating capacity of forest hydrology,terrain factors and fire severity is related to the wetland pattern change. The increase of wet land is remarkable in valley,gentle slope and severe burned area,and also in area with decreasing regulating capacity of forest hydrology.