study of qualitative land suitability classification of major field crops in Tavabe Arsaenjan plains Fars province.

Land evaluation which considering soil and climatic characteristic will caused optimum usage of water ,soil and capital. The aim of this study is evaluation and determination of land qualitative suitability for major crops in the study area. The area covers about 20000 hectares, located in 60 kilometers of East of shiraz. Climate data of the area of study was optaind from the nearest synoptic station (Jhan Abad). The studid sites were selected based on semi- detailed soil survey report of Tavabe Arsaenjan plain. A profile was dug in each soil unit and horaizons of that profile were discripted. A soil sample was taken from each horizon for physical and chemical analysis. According to the soil taxonomy (2006) the soil were classified in three order ( Entisols, Inceptisols and Alfisols). Five main crops including wheat, barley, maize, cowpea and suger beet were selected for evaluation. After data collection, climatic, landscape and soil requirements of selected crops were determined.The parametric method (Storie and Square root method) were used to determine land suitability classes according to FAO system. Climatic data and land charateristics of the study area were compared with climatic and crop requirements respectively and the land suitability class was attributed according to the less favorable characteristics. Result of climatic suitability classification based on different methods showed that climatic class of area studied was moderately suitable(S2) for plantiny wheat, barley and maiz.The results also showed that a large portion of the area studied could be classified as moderatly suitable class.Considering the existing limitations, the studied area was classified from moderatly suitable(S2) to not suitable (N) for the selected crops based on the parametric method. The climatic conditions of the area studied was suitable for suger beet, however determination of the final class of this area depends on soil limitations such as percente of surface and subsurface stone and gravel, land slope and the amount of lime. According to the parametric method, the studied area was classified from (S1) to(N) for suger beet.