Spatial Statistical Analysis Of Ground Water Quality In Henan Province

In this paper,the shallow groundwater quality data of Henan Province in 2015 were selected,and the main components of groundwater quality in the study area were studied by using the variation function model.Firstly,the variogram model of groundwater dissolved solids,sulfate,chloride and potassium permanganate concentration was established respectively.Then the least squares method was used to determine the best variation function fitting model,which revealed the spatial variability of groundwater quality in Henan Province.The results show that the groundwater potassium permanganate in Henan Province has a moderate spatial correlation,the dissolved solids,the sulfate has a strong spatial correlation,and the chloride does not have spatial correlation.The Kriging interpolation of groundwater dissolved solids,sulfate and potassium permanganate in Henan Province was carried out by using the exponential model,Gaussian model and spherical model.The interpolation results of different components are superimposed on the spatial map of the study area,and the spatial interpolation of the chemical composition is obtained.The improved Nemero index method combines the evaluation index of the largest weight value into the calculation of the Nemero index,and improves the Nemero index method only to highlight the maximum defect.The improved Nemero exponential method is used to classify the groundwater quality,and the exploratory spatial data is analyzed.According to the conditions of Kriging interpolation,the ordinary Kriging and Pan Kriging interpolation are selected.The cross-validation of the two interpolation results shows that the universal Kriging interpolation is better than the ordinary Kriging interpolation.From the distribution of groundwater quality,southwest and southern of Henan Province water quality is good,and the northeast especially Puyang,Kaifeng's water quality is poor.Using the variation function to reveal the spatial variability of groundwater quality components in Henan Province,it is very important to visualize the groundwater quality evaluation by using the improved Nemero index method and visualize it based on ArcGIS.It is of great significance to prevent and control groundwater pollution and improve the environmental quality of groundwater.