The Influence of Protection Forest on the Thickness of Accumulated Snow on Grassland

The thickness of snow accumulated near different kinds of protection forest, i.e. shelterbelt (Pinus sylvestris var. mongolica) with ventilation structure, grouped protection forest (P. sylvestris var. mongolica) with closed structure, and the protection forest (Lespedeza bicolor) with loose structure, at Baiyinhua Sand in Fuxin of Liaoning Province were measured. The shape of snow drift on the windward side and leeward side near shelterbelt was long and thin, and distributed evenly. The farther the snow drift away from the shelterbelt, the more even it distributed. The grouped protection forest had the thickest snow accumulated (30.5 cm) on the forest edge on the windward side, but distributed unevenly. The snow accumulated on the edge of leeward side of protection forest with loose structure was 15.8 cm in thickness, and the snow in the forest was thicker than the average. Grouped protection had the greatest influence on the thickness of snow accumulated, followed by the forest with loose structure, and the shelterbelt the least. The effective distance of snow accumulation on lee side was longer (84 m at its maximum) than on windward side (42 m at its maximum). Mathematical equations were established by regression analysis to forecast the thickness of snow at different distances away from the forests.