پديد آورنده :
مومني، مسعود
عنوان :
بررسي اثر تغيير كاربري بر هدر رفت كربن آلي ، نيتروژن و فسفر در دو منطقه از حوزه آبخيز كارون شمالي
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
﴿خاكشناسي﴾
محل تحصيل :
اصفهان:دانشگاه صنعتي اصفهان، دانشكده كشاورزي
صفحه شمار :
پانزده، 114، [II] ص.: جدول، مصور، نمودار
يادداشت :
ص. ع. به فارسي و انگليسي
استاد راهنما :
احمد جلاليان، محمود كلباسي
توصيفگر ها :
توپوگرافي , سوليجان
استاد داور :
مجيد افيوني، حميدرضا كريم زاده
تاريخ ورود اطلاعات :
1396/02/30
چكيده فارسي :
به فارسي و انگليسي:قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
Abstract Water erosion is the major cause to reduce soil fertility and productivity and the mainpath for nutrient transport to freshwaters The discharge of total suspended sediments TSS and dissolved nutrients from watersheds into receiving waters can become aserious problem when natural vegetation is replaced by agriculture TSS is by weight themost important aquatic pollutant and also contains large amounts of nutrients and otherpollutants some of which may later be released into the water column of the receivingwaters This study was conducted to investigate land use change and overgrazing effectson soil fertility changes and nutrient losses by surface runoff Two study areas Soolijanin chaharmahal province and Sadatabad in Esfahan province were selected for this study Land use treatments in Soolijan included 1 moderately degraded pasture MDP with 20 25 vegetation cover 2 highly degraded pasture HDP with 5 10 vegetation coverwith native species of Astragalus Sp Anthemis Sp and Erangium Sp and 3 rangelandthat was cultivated for rainfed winter wheat for 8 years and in two last years cultivatedfor rainfed lentil and in Sadatabad included 1 moderately degraded pasture SMDP with 25 30 vegetation cover and 2 high degraded pasture SHDP with 5 10 vegetation cover and native species of Astragalus Sp and Daphne Sp Soil samples werecollected from the depth of 0 10 cm to determine organic carbon OC total andinorganic nitrogen total inorganic and organic phosphorus available phosphorus andsome organic phosphorus fractions A rainfall simulator ran for 2 hours with intensity of60 5 mm hr at 30 slope and runoff samples were collected after 30 60 90 and 120minutes The results showed that the amounts of OC and total nitrogen significantly p 0 05 reduced due to cultivation 54 5 and 41 Also the amount of OC and Nsignificantly decreased due to overgrazing 37 8 and 27 in Soolijan and 41 1 and41 in Sadatabab watersheds respectively Significantly p 0 05 lower amounts oftotal organic P were found following cultivation 23 9 and overgrazing 18 2 and 43 3 in Soolijan and Sadatabad respectively The largest depletion of labile organic P 72 3 and moderately labile organic P 24 3 was observed in rainfed land inSoolijan Overgrazing led to decrease in labile organic P 42 1 and 64 4 moderatelylabile organic P 13 9 and 35 7 and nonlabile organic P including moderately resistantand resistant organic P 12 9 and 44 4 in Soolijan and Sadatabad respectively Muchhigher runoff sediment and nutrient losses were observed under rainfed area HDP andSHDP than those under MDP and SMDP Contribution of particulate phosphorus andnitrogen exported from micro plot via surface runoff was increased by decreasing theplant cover Concentration of total dissolved phosphorus TDP in runoff wassignificantly decreased by increasing in runoff volume TDP and nitrate concentrations inrunoff collected from all land uses were more than the critical levels established byenvironmental authorities to inhibit eutrofication of surface waters Maximum losses ofTDP and dissolved nitrogen in two study areas were observed in HDP 16 4 mg M2 andrainfed land 117 2 mg M2 and SHDP 47 6 and 307 4 mg M2 respectively
استاد راهنما :
احمد جلاليان، محمود كلباسي
استاد داور :
مجيد افيوني، حميدرضا كريم زاده
