Effects of major forest types of Xiaoxingan Mountains on the process of snowfall, snow cover and snow melting.

Five major forest types were selected in Xiaoxingan Mountains, northeastern China. Its snow hydrological processes,such as snowfall,snow cover and snow melting,were studied. The results showed: 1) snow interception in forest land was mainly impacted by canopy density and main tree species composition. Picea sp.，Abies nephlolepisPinus koraiensis forest had the largest impact on the interception of snowfall, and the snow interception rate was 39.7%, which was 5 times that of Betulla platyphylla secondary forest and 25 times that of Larix gmelinii plantation. 2)The interception amount of different forest types was related to snow intensity.And interception rate was also various in different snowfall intensities for the same forest type. 3) Thickness of snow was the smallest in Picea sp.，A.nephlolepisP.koraiensis forest and reached the peak of 32 cm in midMarch, which was reduced by 12 cm than that of B.platyphylla secondary forest and L.gmelinii plantation. 4) Snow melting speed was quite different in varied forest types. From midApril, the average thickness of snow in P.koraiensis forests reduced by about 0.5 cm per day, while it was by about 1.3 cm in B.platyphylla secondary forest and L.gmelinii plantation, and the comparatively fast snow melting speed was proned to produce the melting flood peak. Therefore, it is necessary to plant conifers and protect the broadleaved trees, and gradually transform the secondary forest into the natural forest of mixed broadleafconifer forest in the northeast region, which can effectively extend the snow melting time and in turn play the hydrological benefit of forest snow melting in this region.