ارزيابي توان زيست محيطي مناطق خشك و نيمه خشك با استفاده از توانايي هاي سامانه اطلاعات جغرافيايي (مطالعه موردي : حوضه آبخيز بيرجند)

Using the Ability ofGeographic Information System in Evaluation of Environmental Capability in Arid area (Case study: Birjand Auriferous Basin)

Land use management policy and method are two important factors in usage of land by human. In this regard , Evaluation of env ironmental capability would serve as a valuable basis for the best use practice of soil and wat er resources in addition to the reduction in environment consequences of the projects. In the current study, the environmental capability of Birjand, located in the south khorasan province, has bee n evaluated using the delivery method. Result shows that salinity and Alkalinity, under loped soil profile, inappropriate soil texture, low and dispersed precipitations and lack of adequate plant coverage are the most remarkable limitation in agricultural usage of the land in Birjand. By combining the maps of geographical dimensions land slop, altitude suitability and plant coverage, considering ecologic - climatic, population and hydrologic characteristics. Result also shows that a considerable portion of the plan, excluding the central parts, is not suitable agricultural use . Aquatic agric ultural is only possible in the area above the aquifer in the plain area. User Dryland Farming in the range of aquifer and aquifer levels slightly higher than on the upper and plains Trashay range and appli es in areas with deep soil s and user garden area aquifer and valleys and mountainous part of the manifestati on aqueduct. Results also show that only area having slopes of abo ve lOis suitable