3435

3250

كارشناسي ارشد

﴿ خاكشناسي كشاورزي ﴾

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1385

دوازده، 92، [II] ص. : جدول، نمودار

ص. ع: به فارسي و انگليسي

محمود كلباسي، حسين شريعتمداري

مجيد افيوني، اميرحسين خوشگفتار منش

فرشيد نوربخش، جهانگير بري كوپائي

مهندسي كشاورزي

ID3250

به فارسي و انگليسي: قابل رويت در نسخه ديجيتال

Abstract Long term application of P containing fertilizers especially organic fertilizers usuallyincreases the water soluble and soil available P content and at the same time may result in Paccumulation in soil Organic fertilizers also may enhance movement of P in the soil profilethat could result in surface and ground water pollution This study was conducted in Lavarkexperimental site on the field plots that received 3 rates 25 50 and 100 ton ha of soliddairy manure sewage sludge and urban solid waste compost and one rate of chemicalfertilizers 250 Kg ha urea plus 250 Kg ha mono ammonium phosphate for 1 2 3 4 or 5consecutive years to investigate the residual and cumulative effects of organic and chemicalfertilizers on water soluble and bio available P as well as P sorption index of the soil Thedesign of this experiment was split plot in a randomized complete block Fertilizers werespread evenly on each plot and were incorporated into surface 0 30 cm soil Eachtreatment was replicated three times Soil samples were taken from 0 30 cm depth of theplots and analyzed for water soluble bio available P and P sorption index Water solubleand bio available P as well as organic matter content calcium carbonate equivalent pH andEC were determined in the soil samples Average organic matter content of soil increasedas the result of organic fertilizer application The increase was proportional to the rate andwas highest for diary manure and lowest for urban solid compost Both water extractableand bio available P contents of soil increased with the rate of application the nature oforganic fertilizer and the number years of applications with the rate being the mosteffective and the nature of fertilizer the least effective Dairy manure had the largest andsolid waste compost the smallest positive impact on both water soluble and available Pcontent of soil Residual and cumulative effects of chemical fertilizer on water extractableand available P content of soil was generally higher than the effect of the lowest rate butwas much lower than medium or high rates of organic fertilizers Effect of sewage sludgeapplication on available P content of soil was greater than its effect on the water extractableP Phosphorus sorption index was independent of the source of P organic or chemical thenature and the rate of organic fertilizers and was only significantly dependent on thenumber years of fertilizers applications Significant correlation between soil organiccarbon and soluble P r 0 77 and available P r 0 81 were observed

محمود كلباسي، حسين شريعتمداري

مجيد افيوني، اميرحسين خوشگفتار منش

فرشيد نوربخش، جهانگير بري كوپائي