بررسی استفاده از مدل ریاضی ‭ANSWERS ‬در پیش بینی روان آب و فرسایش خاک از حوزه های آبخیز کشاورزی استان بوشهر

In recent years a greatly increased emphasis has been placed on improving and maintaining the quality of national water resources. Agencies and individuals from the various levels of government, industry and private life are seeking information concerning the effects that land use, managment and conservation practices might have on the quality and quantity of water both from agricultural and non-agricultural watersheds. Some mathematical models have been developed for calculating run off volumes and predicting eroded soil which ANSWERS model is one of them. ANSWERS, is a deterministic model that uses distributed parameters and is event oriented for simulating hydrologic processes in a watershed. ANSWERS. has been mainly designed for agricultural watershed and is used in different parts of the world. in order to test this model in south of Iran, a 31.5 hactars I 'Ii watershed was selected, Agricultural farms in this watershed have maximum 9,8 and average 1.15 percent slope.The results of this research is as follows: The volume of observed and estimated run off is almost the same and has more then 97 percent coverage. Although peaks of them have a distinict difference. After drawing linear regression between observed and eStimated data , it was shown that correlation through these data was significant at 2 percent. Therefore ANSWERS can be used in those designs which volume of run off is important for us. The estimated eroded soil doesn't adjust with observed one and in some cases, estimated erosion was 3.8 trems more than observed data. Finally, it was observed that ANSWERS had better confidence in simulting medium to high rainfalls than low ones.