【摘要】 通过对青海共和盆地土地沙漠化影响因子 :农牧业人口、牲畜总数、耕地面积、降水量和大风日数 42 a资料的主成分分析 ,结果表明 ,作为最主要综合指标的第一主成分中的人口、牲畜总数及耕地面积的影响 ,贡献率是46 .5 % ;第二主成分中的降水量和大风日数的作用 ,贡献率为 2 4.6 % ;第三主成分中的自然、人为因素 ,贡献率为14.9%。土地沙漠化是众多因子综合作用下生态与经济不相协调的产物 ,其中人口压力下生态不合理的土地利用是其主要原因。更多还原

【Abstract】 Land desertification is a serious global environment problem. Many studies on the causes and evolution of land desertification have been undertaken by specilists and schoolors, and the main causes are natural and anthropogenic factors. In this paper, the Gonghe Basin, Qinghai Province is concerned. The Principal Components Analysis of influential factors, such as population for farming and animal husbandry, livestock numbers, cultivated area, precipitaion and moderate gale days in 42 years, proved that the first principal components, the most major synthetic indexes, are the absolute values of population for farming and animal husbandry, livestock numbers and cultivated area, their offer rate is 46\^5 percent; the second principal components are precipitation and moderate gale days, their offer rate is 24\^6 percent; the third principal components include not only natural factor but also man made factor, their offer rate is 14\^9 percent. The results indicate that the population growth has strengthened the pressure on the environmental system, and because of the unreasonable economical actions, such as cutting firewood and uprooting medicinal materials, and so on, the desertification degree has been deepend and the area has been increased, therefore, the main reason of desertification is caused by population pressure.更多还原