区域尺度地下水埋深与矿化度对土地盐碱化转变概率研究

Study on the probability of salinization transition of regionalscale groundwater depth and salinity

为探明受地下水埋深与矿化度影响的极度干旱荒漠区土地盐碱化转变概率,选定甘肃省景泰川电力提灌灌区(简称“景电灌区”)为研究区,分别利用ArcGIS空间插值中的反距离权重法、样条函数法、趋势面法及普通克里金法对2017年的地下水埋深和矿化度监测数据进行插值,结合误差矩阵选取最优插值方法,并对研究区1994、2008和2017年三期监测数据进行插值分析,再通过重分类消除量纲进行叠加,将土地盐碱化难易程度划分为5级,分析了研究区土地盐碱化转变概率。结果表明,地下水埋深和矿化度平均值在1994年至2017年间呈不断上升趋势,灌区土地盐碱化转变概率西南低东北高,地下水埋深较深区域不易形成盐碱地,地下水埋深较浅区域,矿化度越大越易形成盐碱地,研究可为干旱荒漠区区域地下水利用提供理论依据。

To explore the probability of land salinization transformation in extremely arid desert areas affected by groundwater depth and salinity,Jingtaichuan electric power irrigation area in Gansu Province is selected as the research area,respectively using ArcGIS spatial interpolation of the inverse distance weighting method,spline function method,trend surface method and ordinary kriging method for monitoring data of groundwater depth and mineralization in 2017 for interpolation,combined with the error matrix to select the optimal interpolation method,and the study area,1994,2008 and 2017 the third phase of monitoring data analysis of interpolation,and then eliminated by heavy classification dimension of superposition,the land salinization ease is divided into 5 levels,the land salinization in the study area transition probability is analyzed.The results indicate that the average groundwater depth and mineralization are in the rising trend from 1994 to 2017,salinization transition probability of irrigated land is low in southwest and high in northeast.Saline-alkali land is not easy to form in deep groundwater area,while in shallow groundwater area,the more salinity,the easier to form saline-alkali land.The research can provide theoretical basis for arid desert area groundwater utilization.