ّFarhad Azhir; Mohammad Fayaz
Abstract
It was necessary to detect Technical knowledge for advising culturing various plant species which share in production forage rangelands depend on region condition. Vicia subvillosa species seeds were collected from ranges around road direction Azadshahr city toward Shahrood city, on 1900 meter height ...
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It was necessary to detect Technical knowledge for advising culturing various plant species which share in production forage rangelands depend on region condition. Vicia subvillosa species seeds were collected from ranges around road direction Azadshahr city toward Shahrood city, on 1900 meter height level form sea, and planted. The goal was to introduce the suitable season and method for cultivating this species in rangeland area. Experiment was performed on Telmadare area in Posht-kooh water spreading station with 350 mm. precipitation and semi dry cold climate. Main treatments include autumn and spring, sowing date, and two subsidiary treatments seedling and planting seed, by split plot completely randomize block design in three repetition were compared. Result showed that there was a significant deference between spring and fall date cultivation, and also between two subsidiary seedlings and planting seed. Seed Germination and survival at growing period in fall season (Germination 30.50%, survival 20.97% ) compared to spring (Germination 21.50%, survival 15.33% ) and planting seed (Germination 32.61%, survival 22.39% ) compared to seedling (Germination 21.39%, survival 13.92% ) were preferred. So with Vicia subvillosa cultivation is possible to produce forage in experimental Station case, and similar climatic ecosystem area.
Hesam Ahmady-Birgani; Sadat Feiznia; Hasan Mirnejad; Hassan Ahmadi; Ken Mc Queen; Mohammad Ghorban Pour
Abstract
This study investigates the mineralogy and physico-chemical properties of atmospheric particulates collected at Abadan (southwestern Iran) near the Persian Gulf coast and Urmia (northwestern Iran) during ambient and dust events over 6 months (winter 2011; spring 2012). Particle sizes collected were: ...
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This study investigates the mineralogy and physico-chemical properties of atmospheric particulates collected at Abadan (southwestern Iran) near the Persian Gulf coast and Urmia (northwestern Iran) during ambient and dust events over 6 months (winter 2011; spring 2012). Particle sizes collected were: TSP (total suspended particulates); PM10 (particulates <10µm); and PM2.5 (particulates <2.5µm). Minerals were identified using X-ray diffraction (XRD); particle morphology and composition were examined by scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDX). Major minerals detected are calcite, quartz, clay minerals and gypsum, with relative abundance related to sampling site, collection period, wind direction, sampling head, and total sample amount. The anomalously high calcite content appears a characteristic feature originated from calcareous soils of the region. SEM observations indicated a wide range of particle morphologies over the 1-50 µm size range, with spherical, platy, cubic, elongate and prismatic shapes and rounding from angular to rounded. Energy dispersive X-ray analysis of TSP samples from both sites for non-dusty periods indicated that the sampled mineral suite contained Al, Mg, Na, Cl, P, S, Ca, K, Fe, Ti, and Si, mostly reflecting calcite, quartz, aluminosilicates, clays, gypsum and halite. Additionally, As, Pb, Zn, Mn, Sc, Nd, W, Ce, La, Ba and Ni were detected in TSP, PM10 and PM2.5 samples collected during dust events.
alireza estelaji; ahmad hajalizadeh; masoud heydarvand
Abstract
Community-based management is a process of management involving local beneficiaries actively in all stages of planning and implementing management programs so that each are at the center of decision-making. Since community-based management contributes greatly to the improvement of bridging social capital, ...
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Community-based management is a process of management involving local beneficiaries actively in all stages of planning and implementing management programs so that each are at the center of decision-making. Since community-based management contributes greatly to the improvement of bridging social capital, present study analyzes the effectiveness of co-management for strengthening social capital. The research population consisted of heads of four villages i.e. Ziyaratshah, Deh Reza, Aostam Ababd-e-Alicharak, and Ali Abad Hashtsad Metri, Rigan County, Kerman province. Since community-based management of arid areas was implemented in this region, it was chosen as pilot. Social capital assessment through network analysis and measurement of trust and collaboration ties applying macro level indicators (whole-network) of local beneficiaries’ network was done. Network analysis questionnaire was applied for data gathering and 33 participants were chosen through whole network sampling method and they were interviewed. It was found out that indicators were at medium level prior to project implementation but they showed positive and incremental trend following the implementation of community-based management. Therefore, this project led to trust building and improved cooperation improved among heads and as a result, bridging social capital enhanced.
Zahra Eslamian; Mehdi Ghorbani; hamed rafiee; tayebe mesbahzadeh
Abstract
In recent years, natural resource economists evaluate and assess the role of natural resources in the welfare of people have put on their agenda. This study, people's willingness to participation in protecting and reviving the desert area NasrAbad, examined the using conditional valuation and tow-dimensional, ...
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In recent years, natural resource economists evaluate and assess the role of natural resources in the welfare of people have put on their agenda. This study, people's willingness to participation in protecting and reviving the desert area NasrAbad, examined the using conditional valuation and tow-dimensional, dual choice questioner. To estimate the willingness to pay logit regression model was used based on the maximum likelihood method, the parameters of the model were estimated. Results suggest that age, occupation, education and horticultural activities, a native of the region, climate change, poor management officials, family income and number of family members, significant positive effect and gender, agricultural activities, overgrazing of livestock , expansion of urban land and Bid a significant negative effect on the bid people are willing to pay. Deontologist people units 0/868 have likely to pay more compared with Cosequentialists people the Marginal effect of these variables to be allocated. the average willingness to pay of the Deontologist and Cosequentialists people in this study to participation in protecting and reviving the deserts of Nasr Abad is estimated to be 32586 and 6524 Rials respectively.
Peyman Amin; Mohammad raza ekhtesasi
Abstract
In the last two decades, the land subsidence, especially in fine-grain plains, cracks emerged in YazdArdakan plain, it is called soil crack. One of the important assumptions in relation to emergence of this phenomenon, withdrawal of water from underground aquifers and decrease the hydro dynamic pressure ...
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In the last two decades, the land subsidence, especially in fine-grain plains, cracks emerged in YazdArdakan plain, it is called soil crack. One of the important assumptions in relation to emergence of this phenomenon, withdrawal of water from underground aquifers and decrease the hydro dynamic pressure and dense sediment. This phenomenon happens in fine-grained sediment and caused damage to building structures, roads, masts. the case study is clay plain lands without desert pavement in East of Yazd. For sampling, 12 samples were taken from three points were selected which one of them in the vicinity of crack and two other points were within 100 meters of side of crack in each point, four profiles were drilled from zero to 120 cm depth. On samples some experiments such as the indicators of changing bulk modulus were measured in different moistures in galvanized metal cube boxes with dimensions of 20 cm, some experiments were done such as Atterberg limit tests, divergence and failure limit. The results showed that liquid limit of the crack’s territory is near to 29 percent and moisture limit of crack is close to 4 percent. the most vertical and horizontal shrinkage in crack soils were 11 and 6 percent respectively. In other words, in per meter depth of sediment, 11 cm subsidence in areas with moisture less than 4 percent is not unexpected. With regard to the specific circumstances of the area, is proposed structural projects, gas lines, water pipes and bridges is not done in these areas.
Mozafar Ansari; Sadat Feiznia; Hassan Ahmadi; MohammadAli Fattahi Ardekani
Abstract
Soil is one of the most vital natural resources in any country. Nowadays, lands are rarely found worldwide without having severe erosion problem. Landslide is one of the soil erosion processes in which a huge volume of soil is washed away. SHETRAN Model was used in this study to assess the landslides ...
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Soil is one of the most vital natural resources in any country. Nowadays, lands are rarely found worldwide without having severe erosion problem. Landslide is one of the soil erosion processes in which a huge volume of soil is washed away. SHETRAN Model was used in this study to assess the landslides being occurred in Zidasht catchment, Taleghan. At the first stage, sediment-water mixed samples were gathered at the outlet of the Catchment for calibration purpose in 2011. To run the model, regions undergoing landslide were identified using GISLIP sub-model. Secondly, after hydrological and sediment production simulations in a sub-model of SHETRAN for the region, calibration was made for spring season. After the calibration process, the model was run again, this time for the regions having landslide (for 418 spots), and in regions where landslide sediments do not pour into water courses, these regions were omitted, the final amount of sediment was calculated using SHETRAN sub-model and the results were compared with the previous studies. The results show that 19.75% of the total sediment belongs to landslides. With regard to the current sediment quantity of about 111248 kg, total sediment in landslides was estimated to be around 120668kg.
mehdi bashiri; Seyede Maedeh Kavousi Davoudi
Abstract
The soil erosion affects watershed health and lead to different negative consequences.Marl is an erosion sensitive rock that due to its special physicochemical characteristics,establishment of vegetation on it is difficult,so,it needs to management.One of the soil improvement methods is dynamic compaction,which ...
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The soil erosion affects watershed health and lead to different negative consequences.Marl is an erosion sensitive rock that due to its special physicochemical characteristics,establishment of vegetation on it is difficult,so,it needs to management.One of the soil improvement methods is dynamic compaction,which applies using devices such as rollers.Also,adding pozzolan is another method for soil improvement to modify its physical and mechanical properties.Because the pozzolan in the presence of water,show adhesive properties in a stable and non-solvent form.Therefore,this study tried to evaluate the roles of soil compaction(using rollers having weights of 0,20,25,30and35Kgs)and adding natural pozzolan(in values of 0,50,100,150and200g/m2)in the taftan-pumice type on marl stabilization in Islam-Qaleh region of Razavi-Khorasan.A factorial experimental design done with3replications and totally75field plots with an area equal to30*30centimeters exposed to a rainfall with a10minutes duration and0/8Mm per minute intensity with a slope of15/5°.The results of statistical analysis in the95%confidence level showed that considering runoff,sediment load and sediment concentration variables together,the main effects of soil compaction and pozzolan treatments are significant(sig.=0/000)but their interaction effect isn’t significant(sig.=0/780).Soil compaction treatment has an increasing and significant effect(sig.=0/000)on runoff and sediment production. But the pozzolan treatment showed decreasing and significant effect (sig.=0/000) on sediment and no significant effect (sig.=0/709) on runoff. Also, the interaction effect of 2 treatments on runoff and sediment was not significant. Therefore, the soil compaction due to degradation of surface sealing and marls structure is not suitable, but according to low price and availability of natural pozzolan, for marls stabilization operations, is suggested as an economic and appropriate option.
hamid hosseyni marandi; mohammad mahdavi; hasan ahmadi; baharak motamed vaziri; abdolali adelpour
Abstract
Abstract Common causes for groundwater quantity and quality changes are infiltration through the seasonal floodwater, effects of the artificial recharge projects and adjacent aquifers, and groundwater extraction for deferent uses. However, recognizing the impact of their contributions to these changes ...
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Abstract Common causes for groundwater quantity and quality changes are infiltration through the seasonal floodwater, effects of the artificial recharge projects and adjacent aquifers, and groundwater extraction for deferent uses. However, recognizing the impact of their contributions to these changes can be often challenging. Still, to understand the changes, monitoring groundwater level and several chemical factors are taken into consideration. Certain problems of course can complicate the analysis of the observations; for instance, insufficient data and manually prepared and measurement intervals can degrade the accuracy of such observations. In this paper, device-measured daily time series of Electrical Conductivity (EC), Temperature (T) and Groundwater Head (GH) are analyzed. The main purpose is to evaluate the groundwater changes and its relation to the processes on the aquifer surface in an arid region. Two wells (PZ2 and W20) with 1,200m distance from each other selected and installed a sensitive device for recording the groundwater level, temperature and salinity fluctuations. Time series of changes from December 2012 to July 2013, were analyzed. Groundwater head in PZ2 showed a decline but in W20 showed a minor rise. Salinity variations were different and were 15.3mS/cm in PZ2 and 1.7mS/cm in W20. The backdrop of increased salinity in the surface layers of groundwater in PZ2 identified and showing a correlation between groundwater head and salinity fluctuation with 83.5% R squire.
shahla dehghan pir; omonabin bazrafshan; arashk hlizadeh
Abstract
Ground water depletion and water shortage are two problems in Hormozgan province which have occurred due to the irregular use and inappropriate management of demand and supply of water in agricultural sector. This research explored the balance of agriculture virtual water trade (imports and exports of ...
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Ground water depletion and water shortage are two problems in Hormozgan province which have occurred due to the irregular use and inappropriate management of demand and supply of water in agricultural sector. This research explored the balance of agriculture virtual water trade (imports and exports of virtual water) and its value in two catchments with different climate in north (Baraftab catchment in Hajiabad) and east (Payab-E Roodan catchment) of Hormozgan province. Based on the results, most of the volume of virtual water in northern catchment is related to wheat and Palm fruit with the amounts of 14 and 0.18 million cubic meters, respectively. Most of the volume of virtual water in the eastern catchment of province is related to Palm fruit (0.8 million cubic meters) and citrus (0.6 million cubic meters) and most of the volume of imported virtual water is related to wheat and rice. Also, Baraftab and Payab catchments are the exporter and importer of virtual water, respectively so that the amount of the balance of trade of virtual water in two mentioned catchments are -11.94 and 17.83, respectively. 64% and 67 % of fresh water in two Baraftab and Payab catchments is consumed to produce the agricultural products. The amount of water self-sufficiency index of virtual water is 86% and 81% and the amount of water shortage index is 66% and 69% in Baraftab and Payab catchments, respectively. These results reveal the severe water shortage in these two catchments.
shahrebanoo rahmani; Ataollah Ebrahimi; alireza davoudian
Abstract
In this study, three methods were evaluated for vegetation mapping. For remote sensing method, in addition to IRS data of LISSIII, Ddigital Elevation Model (DEM) and Normalized Difference Vegetation Index (NDVI) were used for classification of 14 classes of land covers mostly vegetation types using a ...
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In this study, three methods were evaluated for vegetation mapping. For remote sensing method, in addition to IRS data of LISSIII, Ddigital Elevation Model (DEM) and Normalized Difference Vegetation Index (NDVI) were used for classification of 14 classes of land covers mostly vegetation types using a maximum likelihood algorithm. After comparing of produced vegetation maps, overall accuracy and Kappa index were 82% and 79.43% respectively when only the IRS were used. Whereas, the overall accuracy and Kappa index were increased to 93% and 90.63% respectively, when ancillary data of DEM and NDVI were added. Slope, slope direction, elevation above sea level, annual precipitation, temperature, and sun radiation were selected as the main physiographic after a broad literature review. Then the relationship between of these six factors with vegetation types was evaluated. so a multivariate logistic regression was used to draw vegetation map of the study area based on the sixth independent variables. The result showed a predicted vegetation map of 47.08% accuracy.Finally, in the morphological method, relationship between three maps of lithology, undulating form of geomorphology and faces with vegetation/land cover were determined using a neural network synthetic approach and predict vegetation map was drawn as the output. The accuracy of resulted map was 39.1%. Comparison of accuracy of vegetation mapping by three methods of RS, physiographic and geomorphological methods revealed that RS method of vegetation/land cover mapping is significantly promising due to a meaningfully higher accuracy even without using ancillary data such as DEM and NDVI in this method.
Omid Rahmati; Aliakbar Nazari Samani; Nariman Mahmoodi; bahram choubin
Abstract
One of the techniques to eliminate groundwater resources crisis is to carry out artificial recharge projects, which cause infiltration of water from the surface into the aquifer and balance of the water table. An appropriate site selection for artificial recharge is one of the most important steps in ...
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One of the techniques to eliminate groundwater resources crisis is to carry out artificial recharge projects, which cause infiltration of water from the surface into the aquifer and balance of the water table. An appropriate site selection for artificial recharge is one of the most important steps in implementation of these projects, itself. In this study, capability of gridding technique and AHP method was evaluated for zonation of artificial recharge potential. Accordingly, a grid, with cell size 0.1 km2, was defined for rangelands of Chamshor watershed and geological parameters, slope, thickness of unsaturated layer, electrical conductivity and transmissivity were selected for entry into the model. Finally, potential zonation map of artificial recharge project, using gridding technique, Analytical Hierarchy Process (AHP) and weighting linear combination methods were produced for implementation of artificial recharge. In order to assess the model, the project of artificial recharge in the study area was used which has had a successful performance on balancing the water table level, reducing destructive floods and increasing vegetation. Finally, the accuracy of the gridding technique and AHP method was 87.5 percent. In conclusion, the zonation of artificial recharge potential which was obtained by gridding technique and AHP method was reliable and it is recommended to be used in the site selection of flood spreading systems to be able to carry out artificial recharge projects.
REZA SHAHBAZI; Sadat Feiznia; Razieh Lak; Hasan Ahmadi
Abstract
Study of surface sediments of southern Khuzestan plain in Shadegan marshes surroundings was made to understand the nature of the sediments, their classification and determining the most effective physical and chemical characteristics of sediments change. Samples were taken from 27 points inside the work ...
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Study of surface sediments of southern Khuzestan plain in Shadegan marshes surroundings was made to understand the nature of the sediments, their classification and determining the most effective physical and chemical characteristics of sediments change. Samples were taken from 27 points inside the work units. The chemical characteristics of sediment samples containing calcium carbonate, calcium sulfate, sodium chloride, sodium, magnesium, calcium, electrical conductivity, pH and sodium absorption ratio, was measured. After removal all carbonates and evaporates materials, the portion of carbonates-evaporates and terrigenous parts, was specified. Granulometry for terrigenous part was done for terrigenous materials. The new method of classification was performed for these fine sediments containing solutes, which considers the portion of the chemical and terrigenous parts, was performed. In order to specify the most effective factors and variables in the sediment variability, factor analysis and cluster analysis were used consequently. Classification results showed that the sediments are marl, with similar components with Iran tertiary marls. Two main factors, the components of the new classification and the chemical characteristics were controlled sediments variability, while the chemical characteristics had more effective roles. According to the results of cluster analysis, Sodium was the most effective variable which its value varies up to more than 20 in different work units. The results of this study show that the use of the new method of classification together with statistical analysis led to extract more details from flat and broad playa and sabkha environments.
mahdieh salehi; Hossein Arzani; ِAli Tavili; Mahdi Ghorbani
Abstract
Rrecently, rangeland multiple use has been found to be one of the primary solutions to alleviate livestock grazing pressure while improving stakeholder's welfare and per capita income and sustainable management and development. Beekeeping in rangeland as a profitable approach and one of multiple use ...
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Rrecently, rangeland multiple use has been found to be one of the primary solutions to alleviate livestock grazing pressure while improving stakeholder's welfare and per capita income and sustainable management and development. Beekeeping in rangeland as a profitable approach and one of multiple use components in upper Taleghan basin and Saman Orfi of Narian, Dizan and Mehran were studied. The present study was aimed to determine beekeeping suitability as well as ecological and social issues. According to permanent standards and resource sites priority for comprising of these Samans Orfi reserves 4 criteria to be considered such as vegetation,environmental, physical and social issues.These criteria are included overall 14 sub criteria. So Multi-Criteria Decision Making Methods (MCDM) has used because of problem complexity. The hierarchical formed in the 4 levels that is purpose, criteria, sub criteria and options. One of the criteria were qualitative. For accessing logical results, we benefit specialist cooperation. The results showed that social problem are more important than the other criteria in priority. Also, final results of Analytical Hierarchy Process (AHP) indicated that Saman Orfi Narian, and Mehran and Dizin were fall into first to third priorities respectively.
Reza midipour; Reza Erfanzadeh; Marzban Faramarzi
Abstract
Intensive livestock grazing is one of the most important destructive factors in rangelands that leads to decrease of diversity and causes disappearance of sensitive plants. On the other hand, considering the scales in assessment of diversity is very importance to study the variability of plant diversity ...
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Intensive livestock grazing is one of the most important destructive factors in rangelands that leads to decrease of diversity and causes disappearance of sensitive plants. On the other hand, considering the scales in assessment of diversity is very importance to study the variability of plant diversity patterns in different scales. Therefore, current study aimed to investigate the impact of livestock grazing on diversity components in different scales using additive partitioning methods in western country rangelands in the Ilam province. Sampling was carried out in 40 plots of 4m2 in 8 rangeland sites including 4 exclosures and 4 grazing sites. Based on additive partitioning diversity methods, the total diversity was partitioned into additively components within and among samples. The results showed that diversity among sites (β2) had the highest contribution of total diversity that indicated the importance of this scale for conservation practices, and it was due to the variation of composition between sites. In addition, the results represented that exclosure in the semi-arid areas can increase diversity at plot scale, while in the regional scales (diversity among sites or β2) livestock grazing leads to increase in diversity. Therefore, exclosure of rangelands does not necessarily lead to increase in diversity. Also, long terms exclosure can lead to increase evenness that resulting in increasing competition among plants, therefore it could decrease plant diversity.
mahvash gholami; karim soleymani; esmaeil nekoee
Abstract
Landslide is one of the major natural hazards caused financial losses, in lives and destruction of natural resources each year. The aim of this study was comparisons of three models, namely WofE, FR and DSH to the determination of the landslide prone areas in Sari-Kiasar watershed. In the first, 105 ...
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Landslide is one of the major natural hazards caused financial losses, in lives and destruction of natural resources each year. The aim of this study was comparisons of three models, namely WofE, FR and DSH to the determination of the landslide prone areas in Sari-Kiasar watershed. In the first, 105 landslides occurred in the study area were collected based on aerial photographs in the 1:25,000 scale and field studies divided into two group haphazardly to generate training 75% and testing 25% dataset. Then, 17 landslide conditioning factors including geological, geomorphological, hydrological and anthropogenic were prepared to spatial relationship with landslide occurrence in the study area. The most important factors in the occurrence of landslides in the study area were rainfall followed by slope and vegetation. The validation results as a percentage of the cumulative area under the curve (AUC) showed that the success rate of WofE, FR and DSH models are 92.05, 92.05 and 91.31 percent respectively and the prediction rate are 92.72, 92.73 and 85.44 percent respectively. The results show that in terms of the accuracy of the model used to base on success rate, three models are placed in excellent group (0.9 to 1), also in terms of the accuracy of the model used to base on prediction rate, WofE, FR models are placed in excellent group (0.9 to 1) and DSH is placed in good group (0.8 to 0.9). The results showed that the WofE and FR model have a higher prediction accuracy than of DSH model.
leila kashi zenouzi; shahram banjshafee
Abstract
This study aimed to investigate the relationship between expression of soil salinity factors and vegetation cover in Foojerd watershed. To this end, the vegetation types in the region and the formation of relatively homogeneous in terms of soil and topography, soil and vegetation were sampled by a systematic ...
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This study aimed to investigate the relationship between expression of soil salinity factors and vegetation cover in Foojerd watershed. To this end, the vegetation types in the region and the formation of relatively homogeneous in terms of soil and topography, soil and vegetation were sampled by a systematic random sampling. The samples according to the area consists of homogenous units were determined. In each plot characteristics of range species and percentage of vegetation cover were recorded and soil profiles were dug. Depending on the depth of the soil profile and the depth of the roots of the plants were sampled and conductivity, exchangeable sodium, sodium absorption ratio and absorption of sodium in each of the soil samples were measured. Pearson correlation coefficient of salinity and vegetation type and percentage of vegetation cover were calculated using SPSS18.0 software. The results showed that vegetation has a negative correlation with soil salinity factors. Based on analysis of variance and Duncan were revealed that test the type of plant species were depended on soil electrical conductivity and sodium absorption rate and the percentage of canopy cover was affected by soil electrical conductivity and exchangeable sodium content. So soil sodality is the most important limiting factor to grow vegetation in Foojerd watershed.
Ommolbanin Kazemi Gordgi; Hasan Ahmadi; Mohammad Jafari
Abstract
The ultimate aim of any research on the mass movement processes is to prepare zonation map and classify area into different degrees of hazard in order to mitigating related damages. This study was undertaken using F-AHP & GIS within Nekaroud watershed in Mazandaran province. Pairwise comparisons ...
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The ultimate aim of any research on the mass movement processes is to prepare zonation map and classify area into different degrees of hazard in order to mitigating related damages. This study was undertaken using F-AHP & GIS within Nekaroud watershed in Mazandaran province. Pairwise comparisons showed that sub-criteria’s Slope (>30%), elevation (> 1700 m), distance from fault (0-200 meter), distance from river, residual land-use and precipitation (>600 mm) have high weight than others in their group which lead to increasing occurrence of landslides. In the study area much amount of lime stone was found which is effective in reducing landslide. Major parts of central areas of watershed are prone to the most dangerous and high frequency landslides, other parts of watershed classified into medium and a little part is in low danger class.
Ali Golkarian; Abbasali Mohammadian; Abolfazl Abdollahi
Abstract
The first condition for control erosion and improve of watershed with critical status, identify and prioritize areas and catchments with a critical situation. At the time of control activities implementation, this action causes, more considered higher priority areas and conservation programs focus on ...
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The first condition for control erosion and improve of watershed with critical status, identify and prioritize areas and catchments with a critical situation. At the time of control activities implementation, this action causes, more considered higher priority areas and conservation programs focus on such areas. The purpose of this research is priorities for watershed management sub basins of Daryan watershed, using similarity to ideal option (TOPSIS) method. First, in this study, six criteria (population, average production, water resources, agricultural land surface, erosion and formation) to prioritize is selection, and then the weight of each criterion using entropy method was determined. Among the criteria studied population and erosion were the highest and lowest weight respectively. The results showed that among the 38 sub-basins studied, sub basin A10, A’11 and B’7_A’12_C’21 because of high-ranking criteria of population, water resources and agriculture have the highest priority and sub basin C6, C9 and C’7 due to the lower these criteria the lowest priority given to the watershed.
Ali Akbar Nazari Samani; alireza oliaye; sadat feiznia
Abstract
Assessment frequency of springs has become an important issue for land use planning, especially water resource identification and environmental protection.The purpose of this study is to produce a spring occurrence potential map in Bojnourd Basin, based on a logistic regression method using Geographic ...
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Assessment frequency of springs has become an important issue for land use planning, especially water resource identification and environmental protection.The purpose of this study is to produce a spring occurrence potential map in Bojnourd Basin, based on a logistic regression method using Geographic Information System (GIS) and remote sensing (RS). The locations of the springs (359 springs) were determined in the study area. In this study, 14 effective factors including spring were used in the analysis: lineament density, distance to lineament, distance to drainage, drainage density, normalized difference vegetation index (NDVI), profile curvature, tangential curvature, surface rate, vector dispersion, precipitation, elevation, geology, aspect and slope. Binary logistic regression coefficients of the variables by selecting 300 spring randomly. 59 another spring were used for validation that 80.6% of the springs were correctly predicted. The accuracy of the model was measured using ROC curves which showed that accuracy is 86.6 percent which indicates that the model shows high accuracy in the analysis of spring occurrence potential in the study area. The results showed that the distance of lineaments, distance of drainage, drainage density, vegetation index, profile curvature, tangential curvature, vector dispersion, precipitation and slope have the greatest impact on the occurrence of springs. Finally, spring occurrence potential map was divided into four probably classes of very low, low, medium and high. According to the survey results, this method can be used to identify sources of groundwater in karstic zones and has important role in better management of the karstic Basins.
hamed nozari; safar marofi; mahnaz edirsh
Abstract
According to the annual damages of flood in Dez river catchment and the lack of information about water quantity which contribute substantially to the flow of the river in the middle sub-basins, the aim of this study was to determine the contribution of sub-basins flow to total basin flood and to identify ...
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According to the annual damages of flood in Dez river catchment and the lack of information about water quantity which contribute substantially to the flow of the river in the middle sub-basins, the aim of this study was to determine the contribution of sub-basins flow to total basin flood and to identify areas of flooding potential. So, the standard precipitation index was calculated to identify the wettest period in the region. Then, the whole basin was divided into 11 sub-basins and subsequently a rainfall-runoff simulation was carried out by using WMS software. Finally, the contribution of each sub-basin to the outlet flood peak was quantified by successively eliminating sub-basins from the simulation process. The result showed that the Dokouheh sub-basin by decreasing the peak flow (40 percent) is the most effective region in flooding. Then, Hamidabaad with 35 percent and Dez dam with 15 percent are the sub-basins with more flood potential, respectively. In addition, to eliminate the effect of sub-basin area, prioritization was done corresponding to the contribution at the outlet per unit area of sub-basins. Dokouheh with 29 percent, Hamidabaad with 25 percent and Dezful with 15 percent were given first, second, and third rank, respectively
