14955

13460

كارشناسي ارشد

علوم خاك(مديريت و ارزيابي اراضي)

اصفهان : دانشگاه صنعتي اصفهان

1397

دوازده، 105 ص. : مصور، جدول، نمودار

شمس اله ايوبي، حسين خادمي

محمدرضا عبدي

محمدرضا مصدقي ، منوچهر حيدرپور

1398/06/02

كتابنامه

كشاورزي

مهندسي كشاورزي

1398/06/02

2553713

Effects of Forest to Rainfed Land Use Change Forest to Rainfed Conversion on Soil Erosion and Sediment Processes Using Cesium 137 Technique in Lordegan District NAFISEH SADEQI N sadeqi @ag iut ac ir January 15 2019 Department of Soil Science Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Dr Shamsollah Ayobi ayoubi@cc iut ac ir Dr Hosseyn Khademi hkhademi@cc iut ac ir AbstractSoil erosion and deposition in watersheds are considered environmental concerns andtheir control is important for the conservation of natural resources Conventional soilpractices in uplands and improper land use planning and deforestation induced by humanare the main causes of soil erosion Deforestation as one of the main components of landuse change is considered as the greatest threat to global environmental diversity Whenthe soil plant cover is lost after deforestation it is exposed to climatic parameters andconsequently soil structure becomes unstable due to the decomposition of organic matterand becomes very sensitive to erosion and transportation In order to successfully performsoil conservation programs information about the soil loss throughout the landscape isneeded One of the well known approaches to predict soil loss in midterm is to use 137Csradionuclide with a half life of 30 2 years In this study the soil erosion rate was assessedin two land uses and four slope positions after the conversion of natural forest to drylandfarming in Lordegan district central Iran A dryland hillslope and a natural forest hillslopewere selected In each hillslope soil samples were taken from the depths of 0 10 10 20and 20 50 cm in four landscape positions including summit shoulder backslope andfootslope in three transects 20 m away from each other The activity of 137CS wasdetermined in all the soil samples by a gamma spectrometer Also the magneticsusceptibility of soil samples was measured by a Barrington Dual frequency sensor at twofrequencies 0 46 and 4 6 KHz Moreover some soil physical and chemical propertiesincluding pH EC available phosphorus Pava available potassium total nitrogen TN organic matter OM gravel content bulk density particle size distribution and calciumcarbonate equivalent were measured The results showed that in forest land use thehighest correlation was obtained between 137CS and magnetic susceptibility at high 106

شمس اله ايوبي، حسين خادمي

محمدرضا عبدي

محمدرضا مصدقي ، منوچهر حيدرپور