ارزیابی پایداری حوزه آبخیز بر اساس مدل HELP (مطالعه موردی: حوزه آبخیز بهشت گمشده، استان فارس)

In order to achieve a sustainable development approach that guarantees the preservation and survival of watersheds, evaluation of the sustainability of watershed using watershed sustainability Indexes it seems necessary. The aim of this research was the evaluation of the sustainability of Beheshte Gomshodeh watershed Using watershed sustainability index (WSI) in the period of ten years (2006 to 2016). The UNESCO – HELP demonstration was proposed an integrated watershed sustainability index (WSI), based on four  criteria of  hydrologic (quantity and quality), environmental, life, water policy issues and  three parameters of pressure, state, response were used in order to achieve low, medium, and high levels of basin sustainability. The results showed that the pressure parameter with the score of 0.7812 and the response parameter with the score of 0.5312 had the highest and lowest scores for the assessment of the watershed sustainability.Also the results showed that the criteria of quantity hydrology with the score of 0.25 and the environment with the score of 1 are the most and least priorities for management.The value obtained for WSI was 0.6665, which represents an intermediate level of basin sustainability Which pays more attention to the region's sustainability level.