Showing 5 results for Land Suitability Evaluation
S. Ayoubi, A. Jalalian, J. Givi,
Volume 5, Issue 1 (4-2001)
Abstract
Qualitative land suitability evaluation is based on the physical parameters affecting the yield agricultural crops. The socio-economic factors are not considered in such evaluations. This study was carried out to assess the qualitative land suitability for irrigated wheat, barley, maize and rice in northern Baraan. Five soil series and 25 different phases were first delineated. Land utilization types commonly practiced in the region with intermediate input levels were considered. Physical requirements of the crops were determined and ranked using the available information. FAO framework and the proposed method of Sys were used for the evaluation. Qualitative evaluation was carried out according to both simple limitation and parametric methods by comparing land and climatic characteristics with crop requirements.
It was shown that in addition to climatic factors, soil salinity, drainage and some soil physical properties such as texture, gravel and lime are the most limiting factors. Land physical suitability for rice production was very low in most land units. The results from physical evaluation by parametric method were very close to those from the simple limitation approach.
J. Mohammadi, J. Givi,
Volume 5, Issue 1 (4-2001)
Abstract
This study aims to evaluate land suitability for irrigated wheat in Falavarjan region (Isfahan) using the theory of fuzzy sets. This method differs from the usual land evaluation procedures in its use of weight for different land characteristics and in its method of determining land suitability index. The results were compared with those from parametric land evaluation method. The correlation between land indices and observed yield was higher for the fuzzy set method (r=0.35) as compared to the parametric method (r=0.14). The higher relationship given by the fuzzy set method illustrates its potential usefulness and applicability to land evaluation.
S. Ayoubi, J. Givi, A. Jalalian, A. M. Amini,
Volume 6, Issue 3 (10-2002)
Abstract
In quantitative land suitability evaluation, economic aspects land evaluation such as impact of environmental physical factors on crop production and the amount of yield per surface unit are considered. The purpose of this research was to study quantitative land suitability of northern Baraan area located in eastern Isfahan. The study was a continuation of the previously accomplished qualitative land suitability evaluation of the area. The economic studies include economic data collection, matching inputs and outputs and gross margins analysis.
Radiation-thermal production potential of the crops was calculated based on plant physiology and temperature (FAO model), which was 10.45, 10.11, 13.64 and 11.93 ton/ha for wheat, barley, maize and rice, respectively. Radiation-thermal production potential, observed and marginal yields and the results of the qualitative land evaluation were used to perform quantitative land evalution and to determine the corresponding suitability classes. The predicted yield in different land units varies between 1.64 and 9.17 ton/ha for wheat, 1.81 and 9 ton/ha for barley, 2.06 and 9.42 ton/ha for maize and 2.35 and 7.14 ton/ha for rice. Presence of significant statistical correlation between the observed and the predicted yield values reveals the validity of the evaluation methods used. The results from quantitative land evaluation show that most of the land units are slightly to moderately suitable for wheat, barley, maize and rice, while a few are not. The best land utilization type in each land unit can be selected through a combined consideration of quantitative land evaluation results, benefitability of each land unit and impact of the land use on the soil. Rice cultivation is not recommended in the study area, because of its adverse effect on soil physical properties and soil drainage.
A. Jalalian, M. Rostaminia, S.h. Ayoubi, A.m. Amini,
Volume 11, Issue 42 (1-2008)
Abstract
Extension of cultivation areas becomes gradually impossible due to ever-increasing population growth and urban area development in Iran. Therefore, it is very important to use the existing cultivated lands more efficiently. Land suitability evaluation makes the sustainable use of the lands feasible. The objective of this study was qualitative, quantitative and economic suitability evaluation of irrigated croplands for wheat, maize and sesame in Mehran plain, Ilam Province. Soil survey in the field, laboratory analysis of the soil samples, qualitative, quantitative and economic evaluation were different successive stages of this research. In qualitative evaluation, climatic, topographic and soil suitability classes were determined according to the degree of the matching with plant requirements, by parametric (square root) method. Quantitative and economic evaluations were done based on observed, potential and marginal yield analysis. Results of the qualitative land evaluation showed that most of the land units were classified moderately suitable for given crops because of soil limitations. Qualitatively, most of the land units were classified in the same classes as, or in lower classes than quantitative suitability classes for wheat and maize production, due to high management level at the farms. Whereas quantitative classes of sesame were determined lower than qualitative classes induced by low management level for this crop. Economic land suitability classification showed that the wheat production was the most economic land utilization type. Results of the economic assessment suggested that the cultivation of wheat in rotation with sesame would produce the most income for different units and could be increased in future using improvement in management level in the study area for sesame cultivation.
I. Esfandiarpour Boroujeni, Y. Safari,
Volume 18, Issue 67 (6-2014)
Abstract
Comparison of the land suitability variations among the soil map units in viewpoint of pedodiversity indices may provide a good assessment of the soil mapping precision. The main objective of this study was to assess the significance of functional pedodiversity thorough two detailed map units for irrigated wheat and potato for class and subclass levels of suitability in the Faradonbeh plain, using Shannon and Simpson indices. First, soil samples at 35 and 47 sampling sites in the D and E map units, respectively, were collected from the depths of 0-25, 25-50, 50-75 and 75-100 cm. Then, the qualitative land suitability class and subclass of all sampling points for each studied land use, was evaluated based on simple limitation method. Although both indices showed higher values in the subclass level of suitability, but the average functional pedodiversity of the studied map units, indicate a significant difference (95% confidence level), just in this suitability level. It was observed that the significance of the pedodiversity indices is not influenced by the land use type or the analyzed diversity index. Hence, as a supplementary procedure to study the intra-unit variation of the soil maps, use of diversity indices may provide some worthwhile information
