Determination and analysis of groundwater ecological level in Changling County

Abstract

In order to determine and analyze the groundwater ecological level in Changling County, a total of Landsat 8 series remote sensing images from 2017 to 2021, buried depth data of 51 groundwater observation Wells and 47 phreatic salinity detection data in 2021 were collected. Based on the field investigation and laboratory experiment, the spatial and temporal changes of groundwater level and vegetation coverage in the study area from 2013 to 2017 were determined by using remote sensing technology (the Environment for Visualizing Images) and geographic information system. Through the analysis of the vegetation coverage ratio and the relationship between the groundwater depth and diving salinity, we determine the appropriate growth of vegetation in the study area of diving level and diving salinity water. The results showed that from 2017 to 2021 in the average groundwater level and vegetation cover degree decline year by year, the study area northwest shallow depth of groundwater, vegetation cover degree better, however, in the central and eastern regions, the groundwater depth is larger and the vegetation coverage degree is poor. When the depth of local groundwater is 3.3–4.5 m and the phreatic salinity is less than 0.85 g/L, the ecological water level and phreatic salinity are suitable for vegetation growth in the study area. When the depth of local water is less than 3 m, soil salinization occurs in the surface soil near the lake marsh. When the depth of local water was greater than 8.4 m, the phenomenon of soil desertification appeared in some areas of central China.