QE20 : Evaluatin of nitrate and phosphate concentrations in the groundwater of Gorgan plain
Thesis > Central Library of Shahrood University > Geosciences > MSc > 2008
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Abstarct: The Gorganrood basin is one of major catchment areas in golestan province which its area is about 1/141/480 hectars. Most of arable lands in gorgan plain are irrigated by surfacewater and groundwater resources of this basin. In this study , it is tried to recognize the critical points of the basi from and concentration point of view. To carry out this investigation , the selected sampling points in alluvial and hard rock aquifers have been evenly distributed. According to extent of the study area , 191 samples from shallow and deep wells were collected and for all samples the values of EC and pH measured in situ . Also the concentration of and were measured in laboratory. The obtained results show that in both shallow and deep aquifers in the south part which the recharging flows enter to the basin , the quality of water is high while toward center and north of the area the quality of water is destroyed . The values of pH in wet and dry periods range between 6.8 and 9. from Aliabad to Minoodasht , where the basin is recharged by a number of streams , the concentration of ranges from 0.04 to 0.11. It is necessary to mention that there is no pollution in the whole area. In the south , east and north east of the region , where there is a number of recharging rivers , the concentration of in the deep wells is relatively little wich ranges between 2 and 29.2. In the center and north of the study area , where there is no recharging streams and the soli is saline , the quality of water is very low and high concentrations of are observed . according to and maps and aquifer properties, it may be concluded that the concentrations of these ions (particularly ) are in accordance with aquifer properties. such that in regions which the values of transmissivity , hydraulic gradient , and depth of water table are low, the pollution of is observed
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