民勤绿洲地下水埋深影响因素分析及其变化趋势预测

水是民勤绿洲环境保护和经济发展的关键，对影响民勤绿洲地下水资源变化的主要因素及其未来变化趋势进行预测，可为绿洲地下水资源合理开发和利用提供科学依据。利用相关性分析法，找出与民勤绿洲地下水埋深观测值相关性较好的影响因素，然后运用主成分线性回归法确定地下水埋深观测值与其主要影响因素的定量关系，并利用灰色预测法对影响绿洲地下水埋深变化的主要因素（包括人口、粮食产量和上游来水量）及地下水埋深进行趋势预测。结果表明：民勤绿洲的人口、粮食产量、上游来水量、GDP、蒸发量和大牲畜存栏量与地下水位变化密切相关；人口和粮食产量的增加会导致地下水埋深的下降，且人口增加对地下水埋深的影响远大于粮食产量增加对地下水埋深的影响；未来6年中，民勤绿洲人口和粮食产量总体呈增长趋势，上游来水量呈逐年减少趋势，地下水埋深呈下降趋势。

Analysis and prediction of the underground water depth and its influencing factors in Minqin Oasis

Water plays a key rule in environmental protection and economic development in Minqin Oasis. Hence, it is significant to analyze and predict the factors that affect the underground water of the Oasis. This paper firstly calculates the factors that closely correlated to the depth of underground water; then it obtains the quantitative relations between each factor and the depth of underground water by the Principal Component Analysis and Regression Methods. Finally, it predicts the future tendency of these factors. The conclusions of this research are： population, grain yield, runoff water, GDP, quantity of evaporation and the number of large livestock are closely correlated to the depth of underground water; the increase of population and the quantity of evaporation lead to the downward of the underground water, and the former has much greater effect than that of the latter; and the population and the grain yield will increase while the quantity of runoff water and the depth of underground water will decrease in the coming six years.