10867

10009

كارشناسي ارشد

بيابان زدايي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده منابع طبيعي

1394

يازده، 93ص.: مصور

رضا جعفري

سعيد سلطاني كوپايي

1394/10/19

سعيد پورمنافي، رضا مدرس

مهندسي منابع طبيعي

ID10009

94 Mapping sensitive areas to land degradation based on satellite data at regional scale Hadi Eskandari Damaneh Email address hadi eskandari@na iut ac ir Department of Natural resources Iran Isfahan 84156 83111 Isfahan University of Technology Degree MSc Language Farsi Supervisor Reza Jafari E mail reza jafari@cc iut ac irAbstractland degradation is considered as potential or actual production loss as a result of natural or humanfactors In this study a monitoring system was used for mapping land degradation at a regional scale Isfahan province which uses four indices including vegetation cover rain use efficiency RUE surface runoff and soil erosion Vegetation was estimated using 16 day data of Normalized DifferenceVegetation Index NDVI of MODIS sensor MOD13A2 and rain use efficiency was estimated by theratio between Net Primary Productions NPP acquired from MODIS sensor data MOD17A3 toannual rainfall Surface runoff was estimated based on Soil Conservation Service SCS of Americamodel using precipitation vegetation land cover and soil data Soil erosion as one of the mostimportant features of land degradation was modeled and calculated using surface flow vegetation soildigital maps and digital elevation model DEM Then the 4 indicators were combined to identify theareas with the highest degradation potential in Isfahan province The results showed that given thateach indicator is of particular importance in the description of land degradation it is worth while tocombine the vegetation rainfall use efficiency runoff and erosion factors to determine the areas inwhich the degradation takes place The results showed that areas with low degradation risk weredistributed through out the province and covered about 10 of the province also areas with mediumdegradation risk comprised most of the province area about 88 The highest degradation wasobserved in the western part of the province Fereydunshahr county covering that about 2 of thestudy area This region is characterized by Zagros Mountains with high rainfall The vegetation in thisarea is almost in good condition but the extreme exploitation of the vegetation and also due to steepslopes in the region has reduced the ability of vegetation to conserve soil from erosion Overall Theresults of this study showed that remote sensing technology can be used as an effective tool in landdegradation assessment and monitoring The reason is that it can provide calibrated objective repeatable and cost effective information for broad regions Therefore the satellite derived four factor method used in this study has high capability in land degradation studies and can be applied toother similar arid and semi aid environments Keywords land degradation RUE MODIS NDVI NPP Isfahan

رضا جعفري

سعيد سلطاني كوپايي

سعيد پورمنافي، رضا مدرس