Introduction
Agricultural activities, as a foundation of growth and development and part of the rural development process, guarantee the economic life of many villages in the country. However, in recent years, other products' water scarcity and resource limitations have affected these activities. This issue has severely challenged the sustainability and life of rural settlements.
In this regard, organizing and developing an optimal cropping pattern is necessary to achieve the goals of sustainable agricultural and rural development in Iran. To achieve this goal, the cultivation of crops must be commensurate with the capabilities of production resources, especially water resources.
Therefore, determining the appropriate spatial distribution of agricultural lands for the cultivation of various crops is one of the primary foundations for implementing optimal cropping pattern. Accordingly, the present study seeks to identify suitable spatial zoning for wheat and barley cultivation as the main crops in agricultural lands in traditional Lenjanat regions, which are exposed to a growing water crisis.
Data and Methodology
According to the main purpose of the research, the data obtained from spatial distribution maps of current cropping patterns and spatial distribution of suitable lands for crop cultivation.
This study prepared the suitability maps of the major agricultural products at a distance of 10 km on both sides of Zayandeh Rud River in Lenjanat region using multi-criteria decision-making methods.
Thus, the agronomic-ecological needs of the two major crops in the area (wheat and barley) were determined, and a standard map for each crop was classified using ArcGIS software. Then, the digital layers were combined by allocating the weight obtained from the Analytical Hierarchy Process and the Simple Additive Weighting method. Finally, talent assessment and land zoning was performed in four categories from unsuitable to very suitable for cultivating wheat and barley crops. Using the analytical hierarchy process method and experts' opinions led to high accuracy results.
Results and Discussion
The results of the land suitability map showed that 90.6% of the agricultural lands in the study area are very suitable and relatively suitable for the cultivation of the wheat crop. The northern and eastern regions, located in Falavarjan county and the north part of Mobarakeh county, are the most suitable areas for wheat cultivation. As we move from the north and east to the west of the study area, the capability areas for wheat cultivation decrease. Limiting factors in these areas are unsuitable soil texture, low temperature, shallow soil, high slope, low rainfall and drainage.
As for barley cultivation, a large part of the area, equal to 30635.3 hectares (more than 91%), is very suitable and relatively suitable. In these areas, in the northern and eastern parts of Lenjanat, unsuitable soil texture, shallow soil, high slope and low drainage are the most critical limiting factors for barley cultivation.
A comparison of "spatial distribution of land suitability" with "spatial distribution of cropping pattern" shows that the crops in this study (wheat and barley) have been cultivated in a suitable area in terms of the ecological potential of lands.
Conclusion
The results of this evaluation can be used in the spatial distribution of the optimal cropping pattern to select a suitable cultivation site for these two crops and other existing and alternative crops.
Wheat and barley are the major crops usually used in planning optimal cropping patterns, regardless of the economic issues. Considering suitable spatial distribution for wheat and barley, they should be distributed in such a way with the slightest difference compared to the current cropping pattern. On the other hand, a large area of the Lenjanat region is suitable for cultivating wheat and barley. In addition, an agricultural unit may have different capacities for other crops, so it is necessary to pay attention to the ecological potential of other crops. Wheat and barley should be cultivated in lands which are unsuitable or semi-suitable for other crops.
Accordingly, it is necessary to provide spatial zoning of existing and alternative crops in the Lenjanat area with fewer water requirements and higher economic benefits to be introduced in the optimal cropping pattern.
In this study, only agronomic-ecological criteria and needs with available data were examined due to data limitations in assessing crop suitability. Therefore, completing land suitability maps by considering more evaluation criteria such as evapotranspiration and the amount of water available is recommended.
Also, to have a "spatial distribution of the optimal cropping pattern", paying attention to the ecological potential of the lands, also considering other criteria and priorities such as natural, socio-cultural, economic and political criteria is necessary. So, we can develop a cropping pattern that provides a basis for desirable space dynamics.