نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی سابق کارشناسی ارشد دانشگاه صنعتی اصفهان
2 استاد گروه خاکشناسی دانشکده کشاورزی دانشگاه صنعتی اصفهان
3 دانشیار گروه خاکشناسی دانشکده کشاورزی دانشگاه صنعتی اصفهان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Sewage sludge is widely used as a fertilizer and soil conditioner on agricultural lands. However because of high concentration of soluble salts in sewage sludge, it increases soil salinity. The objective of this study was to evaluate the residual and cumulative effects of sludge application on soil salinity. This study was conducted in Lavark experimental site with four rates (0, 25, 50 and 100 ton.ha-1) of sewage sludge. The plots received one, two, three or four years of sludge applications. Corn (Zea mays) and wheat (Triticum sativum) were planted in the first and second half of each year, respectively. Soil samples were collected at the end of wheat growing season at 20 cm increments to 100 cm depth from each plot. Soil samples were analyzed for EC, OC, Na, K, Mg, Ca, Cl, SO4 and HCO3. Sludge application significantly increased concentration of Na, Ca, K and Mg in the soil depths. Concentration of Cl, SO4 and HCO3 also significantly increased with sludge application. However, the effect of residual sludge application on soil salinity was minimal and because of leaching, soil EC did not reach the critical value that affect most plant growths.
کلیدواژهها [English]