تعیین شاخص مطلوبیت زیستگاه (HSI) رودخانه ای اردک سرسبز (Anas platyrhynchos) در رودخانه زاینده رود

Riverine habitats, perhaps one of the best habitats for different species of birds, especially ducks like mallards. so assessment of the suitability indices of riverine habitats for wildlife species biodiversity is important. the zayanderood river was a safe winter habitat for mallard (anas platyrhynchos) witch droughts have made irreversible effects on this habitat suitability.this study was carried out between 88 to 89. the study area was upstream region of the river from the nazhvan bridge to 33pol bridge. each indicator is calculated using hep and the total utility of reef geometric mean was calculated. the results showed that the total utility of the numerical equivalent of 48/0 indicating the serious threats in this region. due to the drought caused the river, in order to keep the tensions in the region necessary actions should be taken and finally recommendations for improvement the habitat must be used.