Journal of Food, Agriculture & Environment, Vol.7 (2), April 2009 843 Evan region qualitative soil evaluation for wheat, barley, alfalfa and maize M. Behzad 1 , M. Albaji 1* , P. Papan 2 and S. Boroomand Nasab 1 1 Department of Irrigation and Drainage, Faculty of Water Sciences Eng., Shahid Chamran University, P. Code 61357-43311, Ahwaz, Iran. 2 KWPA, Golestan road, P.Code 61335-137, Ahwaz, Iran. *e-mail: m_albaji2000@yahoo.co.uk Received 12 January 2009, accepted 9 April 2009. Abstract An area suitability assessment for crop production requires a considerable effort, which can provide necessary information for optimum land use. Agricultural land use has benefited significantly from the use of suitability systems in recent years, and these systems have jointly showed their capabilities in the evaluation and assessment of suitable sites for a variety of crops. Due to the current lack of any proper land management practices for Evan region in Iran, a land suitability evaluation study for key productions of the region was carried out. By using the semi-detailed soil studies and physiologic requirements of crops, qualitative evaluation was carried out by means of simple limitation and parametric methods. The index obtained for barley, wheat and alfalfa was higher in comparison to that developed for maize. Limiting factors in crops yield along with climatic variables included carbonate contents, soil texture and soil depth. From the two types of methods used, parametric methods produced more realistic results in respect to the existing conditions of the region. Key words: Land suitability evaluation, parametric methods (Storie and Square Root Method), simple limitation methods, land series, wheat, alfalfa, maize, barley. www.world-food.net Journal of Food, Agriculture & Environment Vol.7 (2) : 843-851. 2009 WFL Publisher Science and Technology Meri-Rastilantie 3 B, FI-00980 Helsinki, Finland e-mail: info@world-food.net Introduction Considering the rapid growth of the world population, which is in turn a limiting factor to the arable lands around the world, the dire need for effective and efficient application of the croplands have been felt more than ever. Sustainable agriculture would be achieved if lands be categorized and utilized based upon their different uses 8 . Qualitative evaluation of the land suitability consists of determination of the land use for particular applications regardless of yield fulfillment and socio-economic issues 7, 8 . In this view, FAO (Food and Agriculture Organization) took a stride in its Soils Bulletins by introducing various methodologies based upon the above framework 7-10 . In their research in the Province of Ben Slimane, Morocco, Briza et al. 5 carried out a qualitative land evaluation for crop production and fruit-bearing trees under rainfed and irrigated conditions. By the use of the parametric method, they showed that much of the croplands of the region were in critical conditions, the most limiting factors of which including lime content, soil texture and soil depth. The main crops of the area were wheat, barley, pea, bean and onion 5 . Ljusa and Pajovic 17 investigated the land suitability for rainfed agriculture in the province of Larache, Morocco. The study area was characterized by crops, which were separated into three groups as food crops (maize, sugarcane, chickpea, potato, tomato, green pepper, onion, sunflower and wheat), fodder crops (barley, sorghum and alfalfa) and tree crops (citrus and olive), all with different agricultural management. The methodology used for the evaluation refers to the Sys et al. 21 parametric method based on land evaluation framework for rainfed agriculture. The main step of this methodology was matching land characteristics against crop needs, giving in that way suitability rating for each land characteristic. After suitability analysis for rainfed agriculture, all crops could be separated into two groups; the first one where there are crops good for this kind of agriculture and the second one can’t grow without good moisture condition. The first group includes the main part of the different crops: maize suitable in the whole agricultural part; sugarcane suitable in the northern and southern reliefs; potato suitable in the southern reliefs; sunflower suitable in the northern and southern reliefs; wheat suitable in the northern reliefs and in the valley; barley suitable only in the northern reliefs; citrus suitable in small parts in the northern and southern reliefs and olives suitable in the valley and in the southern reliefs. For almost all crops any kind of irrigation is necessary for increasing suitability class. Other crops like chicken pea, tomato, green pepper, onion, sorghum and alfalfa belong to group of crops, which are not recommended for rainfed agriculture. Bienvenue et al. 3 conducted land evaluation of Thies Region, Senegal, for crops such as maize, sorghum, pea, sesame, etc. The evaluation showed that the northern part of the region contained suitable (S1) or relatively suitable (S2) lands for all the crops under study while in northwest part along the shoreline the croplands were unsuitable (N1 and N2) which was due to the domination of sandy soils. The study also indicated that from 60,387 ha of the studied lands, 12,522 ha were highly suitable (S1) for all the crops, 31,540 ha relatively suitable (S1) and 16,325 ha totally unsuitable (N1 and N2) 3 . Breda et al. 4 using parametric (Square Root) method conducted