Estimation of Actual Evapotranspiration and its Spatial Relation with Landuse, Using GIS Techniques Case study: Meshkinshahr area

Considering the importance of evapotranspiration in hydrologic cycle and its various applications in different sciences, calculating amount of actual evapotranspiration is very important. Case study area is the Meshkinshahr in Ardebil province. In this research first, using satellite images of Landsat/ETM +, NDVI maps and landuse was extracted. Then, using meteorological stations statistics in the neighboring Meshkinshahr amount of reference evapotranspiration was calculated with Blanney-Kridel method. We then interpolated these values was extended them to the surface. In the next step by using Brunsell and Gillies method and at the base of NDVI, vegetation fraction values were calculated. Finally, based on the Allen method, vegetation fraction layer multiplied by reference evapotranspiration layer and actual evapotranspiration map was extracted. Spatial analysis using GIS show high actual evapotranspiration take place in good pastures and lowest in urban land.