石羊河流域近50 ａ来水资源变化的定量分析

利用主成分回归分析法,选取石羊河流域的5个影响因素进行定量分析,得到3个主成分,其累计方差贡献率达92.786%.根据3个主成分各自对应的特征向量特点,分别解释为人为因子、温度因子和降水因子并进行回归分析.根据回归方程,近50 a来人为因子在水资源变化过程中起主导负作用,其影响力占总影响力的-58.48%,大大超过了降水因子22.35%的正作用;而温度因子虽其影响力不是很大,只占总影响力的-19.17%,却加剧了水资源进一步减少的趋势.

Quantitative analysis of water resources variation for Shiyang River Basin for recent 50 years

Shiyang River Basin is a typical fragile zone of water resources in arid regions.Long-term natural evolution and human activities have seriously destroyed the balance of the water cyclic system of this region.By use of the principal component regression analysis,5 influencing factors were quantitatively analyzed,and 3 principal components with the accumulative variance contribution rate 92.786% were obtained.According to the corresponding eigenvectors,the 3 principal components were explained as the anthropogenic factor,the temperature factor,and the precipitation factor.The regression analysis shows that the anthropogenic factor plays a leading negative role in water resources variation in recent 50 years,and its effect accounts for-58.48% of the total effect,which is much greater than the positive effect of the precipitation factor with the effect accounting for 22.35%.It is also demonstrated that,although the effect of the temperature factor only accounts for-19.17%,it accelerates the decrease of water resources.