Grass is more important coverage plant in world and it's covered most of city's parks of Iran. Grass irrigation water requirement is very high and its irrigation is very difficult under conditions of water scarcity. In arid and semi-arid region of Iran where water scarcity is a high problem, considering of poor quality water is a good option for solving this problem. On the other hand, industrial and densely populated centers in various locations are producing huge amounts of sewage. Poor disposal of these sewages has caused environmental problems in the vicinity of these locations. Getting rid of treated sewage is another matter, because of the health problems. Some researches have shown that the best way for use of wastewater after treatment is in irrigation. With regard to health problems, this is very important to generated minimum contact between the effluent and people. For this purpose, treated secondary municipal wastewater of Isfahan plant was used to five irrigation treatments were design included: furrow irrigation with normal water (evidence), drip irrigation (DI) with wastewater, sub-surface drip irrigation (SDI) in 15 cm depth with wastewater, sub-surface drip irrigation in 30 cm depth with wastewater, furrow irrigation with wastewater. Based on results of this research, value of wastewater biological index included BOD5, nematodes, total coliform, total bacterial and fecal coliform were over than permissible level. In these conditions, application of DI (or SDI) sand filters caused to decreased wastewater pollution index included 54% BOD5, 98.9% total bacterial, 99% total coliform, 99% fecal coliform and 57% nematode. Also, application of SDI system caused to decrease moisture of soil surface, so decreased total coliforms and fecal coliforms in soil surface and aril part plant where the value of these parameters is more than standard level. Wherever in surface drip irrigation and furrow irrigation were showed high value of these parameters in soil surface and in grass, Such that the average of these parameters showed significant difference between these treatments and evidence. Finally the results of this research shows that if it's using of SDI which has a sand filter and injects wastewater below of soil, can be solved environmental pollution in condition of using wastewater in grass irrigation.
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