现代草地沙漠化中自然因素贡献率的确定方法

A Method for Determining the Contribution of Natural Factors on Sandy Pasture Desertification

基于草地沙漠化发展过程中流沙面积变化模型和植被盖度变化模型，结合沙漠化监测资料，提出了。种定量确定自然因素在沙漠化中贡献率的方法，从而也可以间接地推算人为因素在沙漠化中的贡献率。以内蒙古奈曼旗现代草地沙漠化为例对模型进行了应用，效果良好，并发现人类活动停止后，如果随后不出现持续的干旱年份，沙漠化所造成的流沙一般经过4～5a的时间就会自然消失，说明在计算时段内草地沙漠化中自然因素的贡献率为零。

Based on models for drifting sand cover and vegetation cover and dynamical monitors of desertification, an analytical method was proposed for determining the quantity effect of natural factors on sandy pasture desertification. Models for drifting sand cover include the sand transport rate model, threshold wind model and erosion rate model. The model of vegetation cover is featured by consideration of effect of the drifting sand on utilization of precipitation. The application of the method in the pasture desertification in Neman Banner, Inner Mongolia shows good results. It take about 4 or 5 years for the desertified pasture rehabilitating after the human activities stop, if not drought years occur in succession. Natural factors had no contribution to the pasture desertification in Neiman Banner in recent years.