河套灌区年内地下水埋深与矿化度的时空变化

Analysis of spatial and temporal variations of groundwater level and its salinity in Hetao Irrigation District

该文以内蒙古河套灌区为研究区域,应用统计学方法、普通Kriging、Arc GIS9.0和GS+等工具,分析2003年3个不同特征季节的地下水位埋深和矿化度的时空分布规律。分析表明:在3月份灌区浅层地下水埋深平均为2.5m,且绝大部分区域地下水矿化度<4000mg/L;随着夏灌、秋灌、秋浇后,在11月时浅层地下水埋深减小为1.0m,且大部分区域地下水矿化度>5000mg/L。灌区浅层地下水埋深由灌区西南向东逐渐递减,且自南向北逐渐递增。灌区西北和东南部的地下水矿化度相对较高,中间部分相对较低。浅层地下水埋深与矿化度之间线性关系不明显,但是在特定地区浅层地下水埋深的时空分布规律能够定性地反映出矿化度的时空分布规律,即浅层地下水埋深较大时,相应的矿化度较小;浅层地下水埋深较浅时,相应的矿化度较大。

Based on Hetao Irrigation District,Inner Mongolia and statistical methods,ordinary Kriging method,ArcGIS9.0 and GS＋ etc,the temporal and spatial variability of the groundwater level and groundwater salinity were analyzed at three different irrigation seasons in 2003.The average groundwater level was 2.5m and the mineralization degree M4000mg/L in the major part of irrigation district,while the average groundwater level was 1.0 m and the mineralization degree M5000mg/L in the major part of irrigation district in November.The groundwater level was gradually falling from southwest to east and increasing from south to north.The groundwater mineralization distribution was higher in west and east area than that in middle area in Hetao Irrigation District.The linear relationship between groundwater level and its salinity is not very significant,but the distribution characters of groundwater level could reflected the distribution characters of the groundwater salinity in the certain regions,namely the shallower the groundwater level was,the higher the salinity degree of groundwater will be.