Evaluating the Impacts of Implemented Watershed Management Project on Vegetal Cover and Sediment Yield in Kakhk Watershed Project

This research was carried out to study the impacts of implemented watershed management project on vegetal cover and sediment yield in Kakhk Watershed Project.

In this research in the first stage characteristics of each predicted mechanical operations from detailed studies of Kakhk watershed were recorded. Also, the soil erosion and vegetation condition of area before performancing watershed operation were determined. The characteristics of each watershed management structures such as situation, number, volume and its siltation were measured. The biological conservation and efficiency were studied via measuring percent of grass cover, the numbers of live bushes and trees per unit area. The soil erosion was measured by applying MPSIAC model. Consequently, the present and preliminary conditions of watershed (in terms of soil erosion and vegetal cover) were compared with each other and project efficiency was determined.

This reseasch revealed that due to Kakhk implemented watershed management project the average vegetation cover and dry forage production increased from 25% and 17 kg to 49% and 89 kg, respectively. The mean efficiency of all mechanical activities is 76 %. The rate of soil erosion decreased from 20 to 10 t ha yr-1.

The data analysis revealed that after 20 years of project implementation, the vegetation factors improved obviously and the amount of soil erosion has fallen by 50 %.