Investigation effect of the developing salinity water on the quality of irrigation water and soils physicochemical characteristics of pistachio cultivation of Sirjan area

Sirjan area is one of the important agricultural areas in Kerman province. Sirjan-zeidabad plain is the most important area of agriculture in Sirjan city and the most of it is allocated to culture pistachio. In recent three decades, high application of ground waters, continued droughts and serious evaporation caused the decrease of groundwater level that resulted moving salinity water from the Kheirabad salt pan to nearly pistachio lands. The moving salinity water in this area caused the undesirable quality of irrigation water, change of physicochemical characteristics and decreasing pistachio yield. In order to perform this research, first, topographical maps (1:25000) and satellite pictures of area were applied. Then a number of studied points were chosen and samples of soils and waters at any point were sent to library. At next step, regression of relationships between soil and water considering different parameters such as EC, pH, Ca, Mg, Na, Cl and HCO3 was confirmed by using Excel software. Results showed that all parameters of irrigation water, except PH, have direct effect on factors in soil. This subject shows the effects of unknown waters on changing the quality of soil characteristics especially land salinization. The measured parameters volumes, in areas under effect of developing of salinity water, were unusable for cultivation based on FAO standards The pistachio orchards which had no problems of salinity, had economic production. Also, results showed that time has effect on undesirability of irrigation waters. Finally, for every studied area there was a completed questionnaire in order to predict new ways of removing the problems.