تاثير انواع كودهاي حيواني بر تغييرات كوتاه مدت نيتروژن معدني، نيتروژن آلي محلول و آمينواسيدهاي محلول خاك

چكيده انگليسي :

The effect of manure types on short term changes of inorganic nitrogen dissolved organic nitrogen and soluble amino acid in soil Maryam Barjas m barjas@ag iut ac ir January 2 2019 Department of Soil Science College of Agriculture Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Dr Farshid Nourbakhsh farshid@cc iut ac irAbstract Water and fertilizers are two major inputs in agroecosystems that determine the crop growth rate and theiryields In developing countries continual depletion of available soil nutrient resulted in decreasing theirfertility Under such a condition chemical fertilization is the most effective and rapid way to compensatefor the lost nutrients Soil and water pollution due to extreme usage of chemical fertilizers and the greaterattention of human to the food security and environmental health have led to an increase in theapplication of organic sources of plant nutrients The organic amendments are thought to bring about lessenvironmental risks Organic fertilizers not only supply plant available nutrient such as nitrogen but alsothe reclaim the physical and chemical conditions of soil which make an overall better situation for plantgrowth Number of factors are involved in determining the chemical composition of the organicamendments and that is why they do not possess a constant composition The source of the organicamendment and duration of application are major factors influencing the rate at which nutrients would besupplied to the plants The objectives of this study was to identify the biochemical and biological changesof a calcareous soil following application of cow sheep and poultry feces during a short incubation underlaboratory conditions For this purpose a soil sample was collected from Lavark research station andtreated with the animal feces at the rate of 10 g C kg 1 soil separately and an control treatment with noapplication was also considered The amended soils as well as the control soil were moistened to 50 ofwater holding capacity and incubated at 25 C During the incubation the soils were destructivelysampled at 0 1 3 5 7 11 14 18 22 30 37 50 days and net N mineralization net ammonification netnitrification soluble organic N and amino acid concentrations were determined Analysis of variance mean separation followed by discriminant and regression analysis were performed The effects of fecestype time and their interaction were significant Among the treatments poultry feces caused the greatestrates of net N mineralization ammonification and nitrifications Both cow feces receiving two differentprotein diet consistently resulted in N immobilization in soil Discrimination analysis revealed thatpoultry feces are simply separated from the other amendments Significant correlation was observedbetween net N mineralization and nitrification Soluble organic N was also correlated with amino acidconcentration in soil Regardless of the feces type the greatest concentration of the amino acid weredetected early in the incubation and decreased drastically with time Soluble organic N did not followedthe trend of amino acid Cow feces resulted in net immobilization while application of sheep and poultryfeces caused net N mineralization and nitrification Key WordsFresh feces Time Nitrogen Pure Nitrogen Mineralization Dissolved Organic Nitrogen Soluble AminoAcid 58

برجاس، مريم

تاثير انواع كودهاي حيواني بر تغييرات كوتاه مدت نيتروژن معدني، نيتروژن آلي محلول و آمينواسيدهاي محلول خاك

فضولات , زمان , نيتروژن , معدني شدن خالص نيتروژن , غلظت كل آمينواسيدها , نيتروژن آلي محلول