Evaluating the Groundwater Status of Mehran Plain and Factors Affecting the Quantity of these Resources

With increasing the population growth, the extraction of these resources has increased and these natural resoursees have faced with serious threat. Therefore, the aim of this study is investigating the groundwater status and effective factors on the quality of Mehran plain resources. For this purpose, data of 23 piezometric wells during the years 1337-1373 in Mehran plain aquifer were used and groundwater hydrograph for the plain was plotted. In order to investigating the relationship between land use and groundwater, land use map changes was prepared during three periods of 1994, 2004 and 2014 using satellite images of TM and  ETM+ of Landsat satellite in Mehran region. Supervised Classification Method and Maximum Likelihood Method were used to images classification. The results showed that during this period, the size of agricultural land, residential areas, very poor pastures, and impoverished lands have been increased and in contrast, the size of poor pastures were reduced. The results showed that groundwater level decreased about 16.9 meters during this period as well as a direct relationship between ground water level decreasing and the expansion of residential areas and agricultural lands. The increase of agricultural land use and consequently the increasing of exploitation wells have led to overexploitation and falling of ground water level in this plain. In addition, another factor in reducing the groundwater level in the aquifer of the region is the trend of rainfall changes in the region.