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地统计学方法的应用已由最初的地质学领域广泛推广到土壤学、生态学等领域,但在地下水特征的时空模拟方面应用还较少,结合地理信息系统(GIS),运用地统计学方法分析了石羊河下游民勤绿洲近15年来地下水特征的时空变异规律及其与土地利用变化的关系,并对其变化趋势进行了预测．得到了如下结果：(1)地下水埋深的随机变异特征随着开采强度的不断增大,从1987年的26．32％降到了2001年的0．03％,完全被较大尺度上的结构性变异所取代；而矿化度一直是中尺度上的结构性变异高达99．9％．(2)Kriging插值结果表明,民勤绿洲地下水埋深的分布一直是水质较好的绿洲南部最深厚,从南到北随着水质变差,埋深也变浅．地下水矿化度在空间分布上从南到北逐渐增大；在变化趋势上,高矿化度等值线由北向南持续推进．(3)民勤绿洲近15年来耕地面积增加了3．1×10~4hm~2,使得分布于地下水埋深17m以上的耕地面积净增528．3 km~2,分布于地下水埋深11m以下的林地减少200km~2．同样,分布于地下水矿化度3．0g／L以上的耕地面积净增2×10~4hm~2,其中＞4．5g／L的增加了1．072×10~4hm~2．(4)预测至2015年,地下水埋深下降趋势明显,分布于地下水埋深20m以上的绿洲面积将净增1689．88km~2,达整个绿洲面积的68％；至2015年地下水矿化度高于5．0g／L的绿洲面积将达578．15km~2,全部集中在水质较差的绿洲湖区最北部,部分区域甚至高达7．0g／L以上．
The application of geostatistics has been widely extended to the fields of soil science and ecology from the original field of geology. However, the application of geostatistics in the space-time simulation of groundwater features is still relatively rare. Combined with Geographic Information System (GIS) and geostatistics The spatial and temporal variation of groundwater characteristics and their relationship with land use change in Minqin Oasis in the lower reaches of Shiyang River in recent 15 years were analyzed and their changing trends were predicted. The following results are obtained: (1) The random variation characteristics of groundwater depth have been reduced from 26.32% in 1987 to 0.03% in 2001 with the continuous increase of mining intensity, Sexual variation is replaced; while salinity has been a meso-scale structural variation of up to 99.9%. (2) The results of Kriging interpolation show that the distribution of groundwater depth in Minqin Oasis has always been the deepest in the southern part of the oasis with better water quality. As the water quality deteriorates from south to north, the depth of the groundwater also becomes shallow. The degree of mineralization of groundwater gradually increases from south to north in spatial distribution. On the trend of change, the salinity of high salinity continues to advance from north to south. (3) The area of cultivated land in Minqin Oasis increased by 3.1 × 10 ~ 4hm ~ 2 over the past 15 years, resulting in a net increase of 528.3 km 2 in the area of cultivated land distributed over a groundwater depth of more than 17m, distributed below groundwater depths of 11m Of the forest to reduce 200km ~ 2. Similarly, the area of cultivated land distributed above the salinity of groundwater above 3.0 g / L increased by 2 × 10 ~ 4 hm ~ 2, of which, the value of> 4.5 g / L increased by 1.072 × 10 ~ 4 hm ~ 2. (4) It is predicted that the decreasing trend of groundwater depth will be obvious by 2015, the area of oasis located above groundwater depth of 20m will increase by 1689.88km ~ 2, reaching 68% of the area of the whole oasis; by 2015 the groundwater salinity The area of oasis at 5.0g / L will reach 578.15km ~ 2, all of which are concentrated in the northernmost part of the oasis with poor water quality and even up to 7.0g / L in some areas.