TREND OF SOIL NITRATE CHANGES UNDER IRRIGATION WITH TREATED MUNICIPAL WASTEWATER

Water is one of the renewable resources that play a decisive role in the development of culture and economy of any society. This vital resource has been in short supply worldwide in recent decades due to drought, climate change and increasing population growth, especially in arid-semi-arid regions. The current situation of water in Iran, frequent water and electricity outages, is proof of this claim. One of the management methods to meet the demand for water in agricultural and industrial uses,is the use of unconventional water with the aim of sustainable agricultural development and taking into account its environmental effects and economic efficiency. Because unconventional water resources are of great importance in terms of minerals and nutrients, these types of resources also have a special place in water supply and food production economically (Mojiri, ۲۰۱۱) The richness of municipal wastewater in terms of macro and micro nutrients has caused that during its use as a source of irrigation, the amount of chemical fertilizers on farms to be reduced to an acceptable level (Jaramillo and Restrepo, ۲۰۱۷). Therefore, municipal wastewater has economic value both in terms of water supply to the plant and in terms of supply of nutrients for the plant. Therefore, to prevent possible pollution, the use of this unconventional source of water should be studied from an environmental perspective. Therefore, in this study, the effect of treated municipal effluent as an unconventional source of water and nitrogen supply in alfalfa has been investigated. Also, the accumulation and possible contamination of nitrate in the soil has been quantitatively evaluated.