不同放牧强度对典型草原雪的水文效应

Hydrological Effects of Snow under Different Grazing Intensities in a Typical Steppe

采用冬季野外直接观测法,研究不同放牧强度对降雪、拦截雪、积雪的影响.结果表明,随放牧强度的增加,典型草原积雪深度和积雪量都呈现下降的趋势;冬季典型草原立枯物的高度和盖度与积雪深度和积雪量之间具有显著的正相关性;随植被(枯落物)盖度的增加,雪的风蚀量逐渐降低;在其他条件都相同的条件下,积雪深度和积雪量对典型草原的返青时期土壤含水量和植被盖度具有正向的影响,而对土壤容重具有负向的影响.

Snow observation experiment in a typical steppe of Inner Mongolia Autonomous Region was conducted to study the influence of different grazing intensities on the snowfall, intercepted snow and the accumulated snow in the rangeland. The result shows that the depth and amount of the accumulated of snow decreased with the increase of the grazing intensities. There are significantly positive correlations between the height,cover of litter and the depth,amount of the accumulated of snow in winter. Furthermore,the wind erosion decreased with the increase of the litter cover. The depth and amount of the accumulated snow have positive effect on the soil moisture and plant coverage during next spring. In contrast,the depth and amount of the accumulated snow have negative influence on the soil bulk density.