Study and Determination of Criterias and Decision Trees for Evaluation of Floodwater sprading Projects renewable Natural Resources point of view

Growth of population is the main factor for production of more foods. Aditional food production requires aditional soil and water resources or optuimum use of these resources. generally, soil and water' res~urce are limited, optimum use of these resources are very important. In the most part of Iran, annual precipitation is very low with nonuniform distribution in time, space, intensity and duratin. Mostly, high intensity rains produces strong storms which results high damages. Ground water recharge is very low, and. high ground-water pumping declines the water table in aquifers, and sometimes results subsidence of ground surface. In the arid and semiarid regions, due to high groundwater pumping compare to natural groundwater recharge causes shortage of ground-water storage, and, it has been supposed that these type ofaquifers are' poor with very low storge sufficient, but actually these aquifers with high permeable formation have a high potential to store water. So, optimum use of floods by controlling and spreading of storm water on the land, can change the deserts to green zones and forests with high groundwater storage. The study region with on area of 422. 5 km2 is a part of the Garebaiegan region, which is formed from connection of plains and Jabalbares mountain.this watershed is located at Alluvial fan. The Garebaiegan watershed is located between 530 51' to 54° 13' eastern longtitude and 27° 31' to 280 northern latitude. The other characteristics of this area are as follows: The mean annual precipitation of Fasa climatologic station is 2S43 mm, with minimum and maximum of 16mm and 84.5mm respectively. High groundwater pumping due to climatic situation results decline of groundwater surface and requires the artificial grondwater recharge. So, the main objects of this projecte to prevent the sand flow and fixes the soil particles to prepare a suitable bet for plant growth, extention of forests area, Artificial groundwater rechage produces a safe yield for groundwater pumping. Finally, job production and increasing the people in comes can be considerd as parts of project goals. Flood waters spreading method is implementing in 36 stations of Iran. Evaluating of performance of these station are requested. There is some methods and techniques, for evaluating. For this research decision support system is used. In this system( such as ALESO) land use requirement and land characteristics should be defined. Decision Trees has been drawn to make connection ofLORes and Le_s. " The following LUR's are extracted as main affected factors: 1- Permability 2- Vegatation cover 3 - Soil fertility 4- Ground water 5- Socio-economic