پديد آورندگان :
قنواتي، عزت‌اله نويسنده دانشيار گروه ژيومورفولوژي، دانشگاه خوارزمي , , كرم ، امير نويسنده استاديار گروه ژيومورفولوژي، دانشگاه خوارزمي , , ضياييان ، پرويز نويسنده دانشيار گروه سنجش از دور ، دانشگاه خوارزمي , , منصوريان سميرمي، اسماعيل نويسنده دانشجوي كارشناسي ارشد ژيومورفولوژي، دانشگاه خوارزمي , , بهشتي جاويد ، ابراهيم نويسنده دانشجوي كارشناسي ارشد ژيومورفولوژي، دانشگاه خوارزمي ,
چكيده لاتين :
Introduction
The man, for being able to prevent poverty and the destruction of the land, humans must always behave friendly with nature and the productivity of the land to its productive capacity or potential. In addition to this type of land use should be based on it to be able to make economic and social needs of humanity. The type of exploitation of the land is an important factor.
Erosion and sediment production. The ability to use certain lands for cultivation, such as water, dry farming, etc., prior to exploitation can help to prevent soil loss and reduced efficiency of the land. This causes things much more is planned to determine the land capability Prior to exploitation of the there. In this study, compared the results of the FAO model and parametric models of geomorphologic to determine capability of cultivated land to irrigate. Finally, the best and most efficient models for the region were identified.
Methodology
The study area in southern Isfahan province, the North and North West of the city Semirom, In Vardasht Village, is located in the central part. Methods used to determine the potential for irrigated lands in the study are two types: an Iranian model of FAO and Geomorphological parametric model based on the Analytical Hierarchy Process (AHP). The FAO model, by data collected through field studies and laboratory (Soil, topography and Geomorphological and hydrological data) Land area were classified in six-class limit. These classes are defined in the model so that classes one to three lowest limits for cultivation, and the appropriate classes. The closer we come to the sixth class, will be more restrictions. Data used, the geomorphological model includes seven criteria: Slope, susceptibility to erosion, soil, land units, geology, Height and land use. These data were extracted from satellite images and maps of the region, and then based on the capabilities of each layer; weighting was By Analytical Hierarchy Process model. In the next stage, each of the layers according to their capability for irrigated agriculture are weighting internal (from zero to one). Then in the GIS layers that have a zero weight, are multiplied the weights obtained from the analysis of hierarchical models, and finally output they gathered together. Maps obtained were classified in five classes for irrigated agriculture Capability, very low to very good.
Results and Discussion
FAO in the Iranian model, the output will consist of six classes of the low limit (Two classes for the soil) IIS to the high limit (limit of six classes Topography (VIT)). The output represents the low limit for irrigated agriculture in Lowland area, which is mostly utilized for Agriculture being there. These areas are mostly covered by alluvium of old and young, and the depth of soil is suitable for agriculture, no limits for salinity and alkalinity the soil there. Area Rivers are not prone to flooding conditions, and therefore do not cause drainage constraints. Heights area, including mountains and hills are the units that are for pasture. This class is placed in classes with high limits. Map obtained in the parametric model, the ability of land for irrigated agriculture displays the five classes from very low to very good. Due to the most influence Geomorphological factors in this model, this layer is consistent with Geomorphology of the area, in the output map Low slope, as regions are suitable for irrigated agriculture.
Conclusion
In this study, was due to the availability of some of the layers Information, the parametric model is used (such as topographic maps, satellite images and Map of soil) because the land evaluation results in less time and cost will be given to researchers. Therefore, after the capability was calculated by the FAO, Geomorphological parametric model, using Mentioned layers were used for agricultural capability. Agricultural capability Maps combining the two models showed that these outputs have rated 86% overlapping. The high percentage of overlapping shows that parametric model, this model has good efficiency and can be used in similar situations.
