H. Dialami; J. Givi
Abstract
Abstract Introduction: This research aimed to evaluate the qualitative land suitability for irrigated cultivation of Date Palm (Phoenix dactylifera L. cv Kabkab) using FAO (parametric -the second root formula) and Multi-criteria approaches. The FAO approach has been used by many scholars in different ...
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Abstract Introduction: This research aimed to evaluate the qualitative land suitability for irrigated cultivation of Date Palm (Phoenix dactylifera L. cv Kabkab) using FAO (parametric -the second root formula) and Multi-criteria approaches. The FAO approach has been used by many scholars in different parts of the world and Iran for land suitability assessment. In this approach, the most commonly used method is the parametric method. The FAO approach uses Boolean logic to assess land suitability. This logic has been criticized by a number of land evaluation researchers. Because it does not take into account the continuous nature of the soil variations along the earth's surface and the uncertainty in the measurements. To overcome these shortcomings, the fuzzy analytical hierarchy process (FAHP) was presented to determine the land suitability classes. Land suitability should be determined based on a fuzzy analytical hierarchy process, in which, unlike the Boolean logic, unequal importance of different land characteristics and continuity of soil variations are considered. Materials and Methods: The studied area is located in Kheshet and Komaroj plain, Kazerun County, Fars province, southwestern- Iran; between latitudes 29º 32΄ and 29º 36΄ N and longitudes 51º 20΄ and 51º 22΄ E. Its surface area is 5000 ha. The mean annual rainfall and temperature are 377mm and 23 °C, respectively. The soil temperature and moisture regimes are hyperthermic and xeric, respectively. The physiographic unit is river alluvial plain with a very gently sloping. The entire Kabkab date palm plantation of Fars Province is located in this plain. To fulfill the objectives 10 date palm groves, each with an area of at least 0.5 ha and palm date (Kabkab cultivar) cultivation, aged between 20 and 25 years, identical in soil management and vary soil characteristics were selected. A soil profile was dug randomly in each date palm grove, with dimensions of 1.5 (length), 1(width) and 1.5 (depth) meters and described, using soil profile description (Soil Survey Staff). Soil samples were collected from each horizon. After pre-treatments soil samples were analyzed and some physical and chemical characteristics were measured using standard laboratory methods. The profile site was chosen to have a date palm tree in each of the four corners of the profile. The yield of the four trees in four corners of each profile was measured and their average yield was considered as the yield of the corresponding profile. Meteorological data was collected for a period of 10 year from the nearest synoptic station (Kazerun). Land indices were calculated, using soil and climatic data and FAO (parametric-second root formula) and fuzzy AHP and AHP methods. Weighted average of the climatic and the soil data were used and a land index was calculated for each soil profile. In the fuzzy AHP and AHP methods, relative weight of each of the studied criteria was determined by analytical hierarchy analysis using a pair wise comparison matrix. In the fuzzy AHP method the membership degree for each soil and climatic criteria was determined through an appropriate membership function and finally, land suitability class for each soil profile was determined. Landscape characteristics such as slope, drainage and soil depth were not considered in the land evaluation, because these characteristics did not show any limitation for the date production in the studied area. Finally the accuracy of the methods was compared. Results and Discussion: The results of qualitative land suitability evaluation based on FAO (parametric-second root formula) method showed that about 10 and 90 percent of the studied area were classified as S2 and S3, respectively. Based upon fuzzy AHP method, 100 percent of the studied area was classified as S2 and according to AHP method about 90 and 10 percent of the studied area were in S1 and S2, respectively. According to the results, the suitability classes resulted from AHP method was higher than of the fuzzy AHP and FAO methods. Correlation coefficients between the measured yields and the calculated land indexes showed that the fuzzy AHP method results was more correlated to the measured yield than of the other two methods which indicated that the fuzzy AHP was the most appropriate method for land suitability assessment for Kabkab Date palm plantation compared to the FAO (parametric-second root formula) and AHP methods. Conclusion: According to the results of this research, the fuzzy AHP was the most appropriate method for qualitative land suitability evaluation for Kabkab Date in compared to the other two methods in Fars province, Iran.
Nastaran Esmaeilpourfard; J. Givi; A. Davodian
Abstract
Introduction Due to mining, considerable amounts of heavy metal bearing mineralsare scattered in the atmosphere in the form of dust and make the surrounding air, water and soils polluted.Runoff water movingfrom the mountainstowardsplains may also transport heavy metals from mines to the soils.One type ...
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Introduction Due to mining, considerable amounts of heavy metal bearing mineralsare scattered in the atmosphere in the form of dust and make the surrounding air, water and soils polluted.Runoff water movingfrom the mountainstowardsplains may also transport heavy metals from mines to the soils.One type ofpollutions is contamination withheavy metals.The purpose of the present research has been to investigate the effect of heavy metals of mine on soil, water, plant and dust pollution.
Materials and Methods: Gushfil mine is located 3 kilometers southwest of Sepahanshahr, Isfahan. Soil profiles were dug 500 meters apart along three parallel transects, between east of Sepahanshahr and Gushfil mine. The profiles were described and samples were collected from their horizons. Ore, wells, plant and dust were sampled as well. Total concentrations of lead, zinc and cadmium were measured in the samples. To find the origin of polluted dust and soil, lead isotopes contents in the samples were measured and regressional relationships between the ratios of these contents were investigated.
Results and Discussion Sepahanshahr soils are not contaminated by zinc, lead and cadmium, but within a distance of one to two kilometers from the Gushfil mine, the soils are polluted by zinc and lead. Cadmium contamination was not observed in the studied soils. In all of the soils, the heavy metals content varies downwards irregularly. The reason for this variation trend is that the studied soils are alluvial. In different periods of time, alluvium parent materials have been transported by runoff water from the lead and zinc mines towards the alluvial piedmont plain. The studied heavy metals have been distributed irregularly in different horizons of the soils that have been formed in these parent materials. Lead and cadmium concentrations of drinking water in the studied area are much higher than the maximum amount allowed by the World Health Organization. Cadmium content in all trees of the Sepahanshahr urban park and in alfalfa, lead content in olive trees and lead and cadmium concentrations in Holly hock (Althaea officinalis), Spurge (Euphorbiarigida) and Rhizome (Acanthe phylum bracteatum)are higher than dietaryallowance. Significant correlation between heavy metal concentrations reduction in dust samples and increase of distance from the mine expresses that contaminant heavy metals enter the atmosphere due to mine explosions. In dolomitic sandstone rich in sphalerite mineral, the total amounts of lead and zinc are maximum. The maximum amount of cadmium and too much lead and zinc were observed in a shale fragment, sampled from a location of a fault in the mine. Contents of the three metals were less in black and green shales, compared with the other samples. In dolomitic sandstone rich in gallon mineral, the amounts of the three metals are high and its lead content is maximum with respect to other rocks excluding dolomitic sandstone rich in sphalerite mineral. Significant correlation between ratios of lead isotopes contents of the rocks, soil and dust showed that the soils of the alluvial piedmont plain located at the footslope of the western mountains of the studied area have formed in alluvium parent materials originated from western mountains. The studied heavy metals have been transported together with these alluviums from the mine towards the alluvial piedmont plain. The other origin of these metals is the dust which is produced during the Gushfil mine explosions. This dust is translocated towards the Sepahanshahr and makes the surrounding environment of the mine polluted.
Conclusions: Origin of zinc, lead and cadmium in soil, water, plant and dust in the studied area is rocks of Gushfil mine. Transportation of these metals from the mine towards the environment can be explained by two mechanisms: 1) together with runoff water flowing from the western mountains towards the alluvial piedmont plain and 2) in the form of dust which originates from the mine and moves eastwards. The soils are not contaminated with cadmium. With increase of distance from the mine, contamination of lead and zinc decreases in soil and dust in such a way that in the Sepahanshahr soils, pollution of these metals is not observed. The soils located within a distance of 1 to 2 kilometers from the Gushfil mine are contaminated with lead and zinc. Water is polluted with lead and cadmium and the cadmium content of the plants is higher than dietaryallowance.
J. Givi; F. Raeisi; F. Dehghani
Abstract
Purpose of this research was evaluationof organic matter unstability (ripening) of Histosolsof south-west Shahrekord,using humusunstability indices, including ratios of humic acid (HA) to fulvic acid (FA), sum of organic material types, soluble in alkali (AE=FA+HA) to humin fraction (HUM) and also ratio ...
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Purpose of this research was evaluationof organic matter unstability (ripening) of Histosolsof south-west Shahrekord,using humusunstability indices, including ratios of humic acid (HA) to fulvic acid (FA), sum of organic material types, soluble in alkali (AE=FA+HA) to humin fraction (HUM) and also ratio of optical density at 465 (E4)tooptical density at 665 nanometer (E6) of organic matter and its components.The studied area has cool and semi-arid climate. Some of the soils formed in the studied area are Histosols.Five soil profiles were described down to depth of 2 m and soil samples were collected from their different horizons. Chemical fractionation of organic matter to fulvic acid, humic acid and humin was done and the content of each of these three components and the amounts of E4and E6 were measured.In all of the soil profiles, variations of the fulvic acid, humic acid and humin contents are similar to variations of organic matter contents. More than 94 percent of the soil organic matter has changed to humus. Increase of HA/FA with increase of soil depth indicates high degree of polymerization and humification (stability) of organic matter in underlying layers and higher rate of humic material decomposition (unstability) in surface layers. Lower rate of humic material decomposition in underlying layers is due to increase of clay content with increase of soil depth and adsorption of humin by clay particles. E4/E6 of the whole soil also decreased regularly from soil surface towards soil depth. This decrease is another evidence for increase of organic matter stability. Highest organic matter unstability was observed in the profile 5. This profile contains hemic but the others have sapric organic material.
J. Givi; A. Haghighi
Abstract
Introduction: Land suitability evaluation and land production potential estimation are considered as prerequisites for land use planning. In quantitative land suitability evaluation, land suitability is evaluated based on production per surface area unit. In this kind of evaluation, first, radiation ...
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Introduction: Land suitability evaluation and land production potential estimation are considered as prerequisites for land use planning. In quantitative land suitability evaluation, land suitability is evaluated based on production per surface area unit. In this kind of evaluation, first, radiation thermal production potential is calculated, using different models such as FAO model. This potential is a genetical one which is not under influence of water, soil and management limitations. If soil limitations are exerted in the radiation thermal production potential, land production potential is resulted. The difference between the land production potential and the farmer yield is that the first one is not under influence of management limitation but the second one is under influence of management. Management level is determined based on management index. Canola (Brassica napus) is one of the oil crops which is cultivated in Iran and provides more than 90% of the required oil of the country. This crop is effective in the control of pests, diseases and weeds. Oil of the edible varieties of canola has good quality. After extraction of the oil, the remained meal is full of protein and is appropriate for animal nutrition. The aims of this research have been land production potential prediction and quantitative land suitability evaluation for irrigated canola in the north of Shahrekord. In the present research, for the first time, canola growth requirements were rated for different suitability classes.
Materials and Methods: The studied land with a total surface area of 25 hectares is located north of Shahrekord, in the vicinity of the previous Saman industrial district. The average annual precipitation in the studied area is 370 mm and the mean annual temperature is 13.1 OC. 19 soil profiles were dug and described. Leaf area index, harvest index and canola grain moisture percentage were measured. Farmer yield was also measured for each profile and economic data were collected. Physical and chemical analyses of the soils were done according to the standard laboratory methods. For the first time, canola growth requirements were rated for different suitability classes. In a next step, the measured land characteristics were matched with the canola growth requirements (except climatic requirements) and depending on the limitation level of the land characteristics for canola, a suitability rating was considered for each land property. By using these ratings in the second root and story formulas, soil index was calculated. Radiation-thermal production potential was calculated, using FAO model, considering temperature, solar radiation, leaf area index and harvest index limitations. Land production potential was determined by multiplication of the radiation-thermal production potential and the soil index. Margin yield was calculated by dividing total costs to the price of one kilogram of canola in the market. The limits between quantitative land suitability classes of S1 and S2, S2 and S3 and S3 and N were considered to be 75% of the radiation-thermal production potential, 140% and 90% of the marginal yield, respectively. Management index was calculated by dividing the farmer yield to the land production potential. Management index of 0.75 and 0.50 was considered respectively to be the limits between management levels of high and intermediate and intermediate and low. To evaluate the accuracy of the used methods, the correlation between the land production potential and the farmer yield was investigated.
Results and Discussion: Canola radiation-thermal production potential was calculated as 7603 kg. ha.-1; mean land production potentials, using second root and story formulas were predicted respectively, as 3214 and 2291 kg. ha.-1 and mean farmer yield was measured as 1943 kg. ha.-1. Management level was determined as high to intermediate. The marginal yield was calculated as 2025 kg. ha.-1 The results of this study showed that 59 and 6 percent of the land is marginal (S3) and moderated (S2) suitable respectively. 35 percent of them are not suitable (N). Use of the second root formula is more appropriate than story formula as far as land production potential calculation is concerned.
Conclusion: Moderate limitation of slope and carbonate content and moderate to severe limitation of gravels in the soils are the origin of a difference of 4400 to 5300 kg. ha.-1 between the radiation-thermal production potential and the land production potential. A difference of 348 to 1271 kg. ha.-1 between the land production potential and the average farmer yield is due to the high to intermediate management level. Land physical limitations and management level have caused more than 50% of the lands to have marginal suitability and 35% of them become non-suitable.
J. Givi
Abstract
In addition to qualitative and quantitative land suitability evaluation, economical evaluation can be carried out as well, based on net or gross benefit per surface area unit. The present research was done to evaluate land suitability, qualitatively and economically,, by different methods for irrigated ...
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In addition to qualitative and quantitative land suitability evaluation, economical evaluation can be carried out as well, based on net or gross benefit per surface area unit. The present research was done to evaluate land suitability, qualitatively and economically,, by different methods for irrigated maize, wheat, potato and barley in Shahrekord area. In this regards, qualitative land suitability class was determined by matching land characteristics with the studied crops growth requirements, using simple limitation method and ALES program. Economical land suitability evaluation was carried out, using "internal rate of return", "gross profit", "net present value" and "benefit/cost ratio" methods which are included in the ALES program. The results showed that qualitative suitability class in all of the studied land units for irrigated maize, wheat and barley is S2 and for irrigated potato in 73% of the units is S2 and in 27% of them is S3. As the "net present value" method is used, % 73 and % 27 of the land units are classified as S2 and S1, respectively for all of the studied crops. For wheat and maize, all of the land units are classified as S1, as gross profit, benefit/cost ratio and internal rate of return methods are used. For potato and barley, using gross profit and internal rate of return methods, % 73 and % 27 of the land units are classified as S2 and S1, respectively and as the benefit/cost ratio method is used, economical land suitability class in all of the land units is S1.
J. Givi; A. Abedi
Abstract
Economical profit is one of the important factors, persuading farmers to plant a specific crop. So, in addition to qualitative and quantitative land suitability evaluation, economical one can be carried out as well, based on net or gross profit per surface area unit. The present research was done to ...
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Economical profit is one of the important factors, persuading farmers to plant a specific crop. So, in addition to qualitative and quantitative land suitability evaluation, economical one can be carried out as well, based on net or gross profit per surface area unit. The present research was done to evaluate land suitability, economically, by different methods for maize around Shahrekord city. In this regards, economical land suitability evaluation was carried out, using "internal rate of return", "gross profit", "net present value" and "benefit/cost ratio" methods. These methods are included in the ALES program. For model making in this program, a data base, including soil units, land characteristics, maize growth requirements, yield, discount rate, constant and variable costs and return of one weight unit of maize was established and then economical land suitability classes were determined. The results showed that as the "net present value" method is used, most of the land units are classified as S2. As the other three methods are used, all of the land units are classified as S1. Economical suitability class, determined based on "gross profit" method, without using ALES program, in 40% of the land units is S2 and in 60% of them is S1. The results of the economical land suitability classification, based on "net present value" method, using ALES program, is more in agreement with the results of qualitative land suitability classification of the study area that in a previous research, was done based on just physical land characteristics.
J. Givi
Abstract
Optimal land utilization is important because of land degradation due to incorrect use and ever-increasing need for increasing yield per surface area unit. For this optimal use, crop specific land suitability evaluation is essential. The aim of this research was qualitative land suitability evaluation ...
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Optimal land utilization is important because of land degradation due to incorrect use and ever-increasing need for increasing yield per surface area unit. For this optimal use, crop specific land suitability evaluation is essential. The aim of this research was qualitative land suitability evaluation for maize production in Shahrekord area and validation of the applied land suitability evaluation methods. In this regards, land suitability class was determined by matching land characteristics with maize growth requirements, using parametric method and ALES program. For model making in ALES program, simple limitation method was used, a data base including soil units, land characteristics and maize growth requirements was established in the program and then land characteristics were matched with the maize growth requirements. The results showed that as the square root formula of parametric method and the ALES program are used, most of the land units are classified as S2c. As the storie formula of the parametric method is used, because of multiplication of the suitability ratings and not due to land characteristics limitations, most of the land units are classified as S3c. The most important limiting factors for irrigated maize production in the study area are average minimum temperature and mean ratio of sunshine hours to day length of the growing cycle. In some of the land units, soil pH is considered as limiting factor as well.
J. Givi; M.R. Nouri
Abstract
Proper use of agricultural lands is essential because of fast growing population and water stress which occurs in arid and semi-arid regions. In this regards, land suitability evaluation and land production potential prediction are two important prerequisites for land use planning. This research was ...
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Proper use of agricultural lands is essential because of fast growing population and water stress which occurs in arid and semi-arid regions. In this regards, land suitability evaluation and land production potential prediction are two important prerequisites for land use planning. This research was done to compare FAO and Wageningen models which were used in land production potential prediction for irrigated maize and to determine management level around Shahrekord city. For this purpose, first, radiation thermal production potential for irrigated maize was estimated, using FAO and Wageningen models. Then, land production potential was calculated by multiplication of soil index and radiation thermal production potential. Soil index, indicating the extent of soil limitations effective in production reduction, was calculated by the Storie and the second root formulaes. The potential, obtained by the FAO model is higher, compared with that calculated by Wageningen model. This difference is due to difference in calculation method and different forms of the models. The results showed that the land production potential is higher than the observed yield. Management level of the farmers is the origin of this difference. By using two methods, it was proved that management level in most of the land units is high. Determination coefficients of correlation analysis between land production potential and observed yield were obtained as 0.7383 and 0.7850, using FAO model, and as 0.7385 and 0.7775, using Wageningen model, respectively as Storie and second root formulas were used for calculation of soil index. This means that the land production potential and the observed yield have a significant correlation and accuracy of the used methods for estimation of land production potential is acceptable. Factors that increase the determination coefficient are discussed as well.
