过牧对玛曲草地沙化的影响  

Effect of overgrazing on grassland desertification in Maqu County

作　　者：牛叔文[1] 马利邦[1] 曾明明[1] 

机构地区：[1]兰州大学资源环境学院,中国兰州730000

出　　处：《生态学报》2008年第1期145-153,共9页Acta Ecologica Sinica

基　　金：国家软科学资助项目(2003DGS3B039)~~

摘　　要：玛曲草地沙化对黄河上游水源补给产生了不利影响。基于NPP和理论载畜量的估算,定量分析了自然因素和人为因素对草地沙化的作用程度。结果表明:影响玛曲草地沙化的自然因素主要是温度升高,特别是≥0℃积温的增加;人为因素主要是超载过牧。温度升高对草地沙化的影响占34.39%,超载过牧占65.61%。草地沙化是过牧的累加效应达到一定程度时才出现的,累加超载量每增加1万个羊单位会造成3.14 hm2草地沙化。草地沙化的防治应以草畜平衡为基础,逐渐减缓或减少超载量的累加。Grassland desertification in Maqu County adversely affected the replenishment of the water sources in the upper reaches of the Yellow River. Based on an estimation of NPP and the theoretical livestock capacity of grassland, the effects of natural and artificial factors on grassland desertification were analyzed quantitatively. The results were as follows： the key natural factor that affected grassland desertification was increasing temperature, especially the accumulated temperature of ≥0℃, and the key artificial factor was overgrazing. The effect of temperature increase accounted for 34.39% of the grassland desertification and overgrazing for 65.61%. The grassland desertification phenomenon did not appear until the accumulative effect of overgrazing was considerable. An increase of 10 000 sheep units in the accumulated overstocking capacity would cause grassland desertification of an area of 3.14 hm^2. Protection of grassland from desertification should mitigate or gradually decrease the accumulated numbers of overstocking on the basis of the forage livestock balance.

关 键 词：NPP 理论载畜量 过牧 草地沙化 玛曲县 

分 类 号：S812[农业科学—草业科学]