environmental impact assessment of hormozgan province (s. iran) by degradation model

environmental impact assessment (ela) today is a planning tool that is used for the prediction of environmental impacts. there are several methods to assess environmental impacts in the world and iran as well. among them system analysis approach using degradation model (makhdoum, 1996) has shown it's effectiveness. degradation model is used at different levels including the basin , catchment area, girds and environmental units. the study area, hormozgan province includes 805 (4x4 cm) ut.m. grids on 13 1:250000 topographic maps sheets. in every grid, degradation coefficients were computed on the basis of degradation model as follows: =d.ci according to the above relation, 20 degradation impacts and their intensities were identified and classified following sit e visit and office works. physiological density was calculated by deviding the population by the areas of farming lands (mille r, 191:)7). in order to detemine the degree of ecological vulnerability, grids were classified into four classes by employing a specified mathematical relation, and considering parameters limitation code (slope, elevation, soil, geological condition, plant coverage and climate) . degradation coefficient were computed by the division of the sum of degradation impacts and physiological density on the ecological vulnerability for every grid. then by sorting these coefficient they were classified into six classes . these values also could show the degree for devolopment of the grid, in a way that the more the values the more is the degradation , which is less prone to development. finaly according to the present situations development priori ties were determined.