Mohammad Taghi avand; Saeed Janizadeh; Mohsen Farzin
Abstract
Increasing population and agricultural development need dramatically water resources groundwater resources, therefore, are increasingly being considered, especially in arid and semi-arid regions. Aim of this research is mapping potential of groundwater resources on Yasouj-Sisakht region using data mining ...
Read More
Increasing population and agricultural development need dramatically water resources groundwater resources, therefore, are increasingly being considered, especially in arid and semi-arid regions. Aim of this research is mapping potential of groundwater resources on Yasouj-Sisakht region using data mining method Random Forest (RF) and Generalized Linear Statistical Model (GLM). For this purpose. For this purpose, information layers including slope, slope direction, slope length, aspect, topographic wetness index (TWI), distance from fault, distance from the stream, rainfall, land use, lithology, topographic position index (TPI) and stream power index (SPI) as the main factors influencing groundwater potential were identified and developed in ArcGIS and SAGAGIS software. From the distribution of 263 springs in the area, 70% (253 springs) were used as educational springs and 30% (109 springs) were used as experimental springs. The results showed that the level of underground water with low, medium, high and very high potential in the map of the random forest was 37.78, 22.22, 18.89 and 21.11%, respectively, and in the generalization linear model were 14.49, 32.04, 31.11 and 22.36%, respectively. Moreover, Sensitivity Analysis show that the factors affecting both methods are rainfall, altitude and distance from the fault factors. The accuracy of the data mining models used in this research was also evaluated using a relative performance curve (ROC). The area under curve (AUC) for both RF and GLM models is 92% and 65%, respectively. The accuracy of RF model, therefore, mapping groundwater potential in the study area is more than GLM model.
majid mohammad esmaeili; mohammadreza Mojtahedi; Khironesa Mirnia
Abstract
Flooding is one of the most important environmental stresses that affect the performance of plants. The effects of flooding height on the performance of the two species A.littoralis, J.maritimus were studied. This experiment was carried out the factorial experiment in a completely randomized design with ...
Read More
Flooding is one of the most important environmental stresses that affect the performance of plants. The effects of flooding height on the performance of the two species A.littoralis, J.maritimus were studied. This experiment was carried out the factorial experiment in a completely randomized design with 4 treatments and 8 replications. After 2.5 months of ultimate recovery tests were performed. The number and length of stolons of A. littoralis were counted separately in each treatment. The number and length of rhizome J. maritimus species in each plot (pot) were counted. The total weights of dry matter, shoot dry weight, dry weight of underground organs were measured in each experimental unit. Analysis of variance showed that the effects in controlling the height of flooding on all performance indicators studied (excluding the effects of flooding on root dry weight) of two species A. littoralis and J. maritimus is significant. Comparison of performance indicators A. littoralis species show between the two treatment groups (7 cm below the water level and water treatment) and treatment (treatment without irrigation and 15 cm below the water level) there is a significant difference. Comparison of performance indicators J. maritimus species show a significant difference in the number of rhizome, total length of underground rhizome and dry weight were observed. Comparison of dry pasture species show the highest production of the two types of treatment 7 cm below the water level.
Alireza Eftekhari; Mohamad Jafari; Hossein Arzani; Aliakbar Mehrabi; Mohammad Reza Bihamta; Ehsan Zandi Esfahan; Nadia Kamali
Abstract
Given the role of rangelands in soil conservation and soil fertility, strengthening the soil of rangelands could be achieved by range management plans (RMP). Therefore, in this research, 15 summer rangelands and 16 winter rangelands with RMP were investigated to determine the effects of range management ...
Read More
Given the role of rangelands in soil conservation and soil fertility, strengthening the soil of rangelands could be achieved by range management plans (RMP). Therefore, in this research, 15 summer rangelands and 16 winter rangelands with RMP were investigated to determine the effects of range management plans on some soil properties. In each rangeland with RMP and in each vegetation type, three soil profiles were dug and soil samples were collected at two different depths. Beside each rangeland with a RMP, a rangeland with a same vegetation type and without RMP was selected for comparison and sampling was conducted. Organic matter, nitrogen, potassium, and phosphorus were measured in the laboratory. The data from two different range management types were analyzed in an independent sample T test using SPSS software. The results showed that, in summer rangelands, range management plans could increase the amount of some factors like phosphorus, nitrogen, and organic matter, while it had no significant impact on some other factors, including the amount of potassium and increasing the depth of horizon A. However, in the winter rangelands, the plans had no significant effect on strengthening the soil of rangelands and it seems that due to the slow changes of soil in arid areas, more time is needed to make significant changes in the soil.
hamid barghi; Bahman Shafiei; ahmad hajarian
Abstract
The present study was conducted using analytical-descriptive methods with the aim of investigating the limitations and abilities of using the rangelands of Kermanshah province by Dehyar using AHP and SWOT models. The statistical population consisted of experts from the Natural Resources Bureau of 14 ...
Read More
The present study was conducted using analytical-descriptive methods with the aim of investigating the limitations and abilities of using the rangelands of Kermanshah province by Dehyar using AHP and SWOT models. The statistical population consisted of experts from the Natural Resources Bureau of 14 people. The tool used to collect the data was a questionnaire which was designed according to the review of the field of research and individual interviews with the experts of the Natural Resources Bureau of the region. Data collected using SWOT and AHP model have been investigated. The results indicated that the most important points in the field of exploitation of rangelands in Kermanshah province are determining the appropriate season and grazing time in rangelands with a weight score of 0.96, the most important weakness, non-principled exploitation of rangelands with a weight score of 1.04, the most important opportunity , The beginning of activities for preserving rangelands in Kermanshah, such as seeding of rangeland species proportional to climate, soil and ... with a weight score of 1.02, and the most important threat is the lack of precise monitoring and strong management of the unit in maintaining pasture and inter-system coordination with a weight score of 0.80. Also, in the prioritization of strategic factors based on the AHP model, it was observed that the most important non-principle exploitation of rangelands with a weight of 0.289 and then the beginning of conservation activities in Kermanshah, such as seeding of rangeland species proportional to climatic, soil and
Jahanbakhsh Teymuri Majnabadi; Parvin Ramak; vahid karimian
Abstract
The present research aims to investigate the effect of temporal succession on the biological operation of planting Haloxylon persicum on the functional characteristics of rangelands in Khaf County. Three rangelands in which H. persicum planting operations were performed at different ages of 10, 20 and ...
Read More
The present research aims to investigate the effect of temporal succession on the biological operation of planting Haloxylon persicum on the functional characteristics of rangelands in Khaf County. Three rangelands in which H. persicum planting operations were performed at different ages of 10, 20 and 30 years, and the control area were selected. Sampling along 3 transects of 100 meters, located 10 meters apart, were measured and analyzed for each area and a total of 12 transects. Using the function analysis method, three characteristics of stability, infiltration and nutrient cycle were measured using 11 soil surface indexes. The results showed that there is a significant difference between the succession times for biological restoration from the functional point of view (P <0.01). The highest degree of stability and infiltration is related to the H. persicum range of 30 years old and the smallest of it belongs to the control area. There is a significant difference between the biological regeneration time of H. persicum planting and the control area in terms of nutrient cycle index (P <0.01). The highest levels of nutrients are related to the 30-year-old H. persicum, 20-year-old H. persicum, 10-year-old H. persicum, and the control area. In general, the results of the present study indicate positive biologic effects on the characteristics of the rangeland function, and these positive effects are evident in increasing the functional indexes over time.
saeedeh joriz; Meghdad Jourgholami; arash malekian; maryam etehadi
Abstract
Land use changes can significantly affect the hydrology of a forest watershed. Ground cover is important to protect the soil against erosion. Timber harvesting has been changed the canopy cover and forest soil was exposed to the wind and water. Soil compaction and removing the forest floor in the skid ...
Read More
Land use changes can significantly affect the hydrology of a forest watershed. Ground cover is important to protect the soil against erosion. Timber harvesting has been changed the canopy cover and forest soil was exposed to the wind and water. Soil compaction and removing the forest floor in the skid trails was reduced the capacity of water absorption in mineral soils and thus reduced water infiltration, increased runoff, which caused to soil erosion. In order to measure the rate of sediments in two slopes and to study the effect of skid trails on the amount of sediments, the plot-level study was carried out in the Gorazbon district in Kheyrud forest in the control area and skid trail after skidding operations in the sample plot. The results showed that the most sediment value was 1.938 g. liter-1 in the skid trail with a 20-40 percent slope in the autumn and the lowest deposition was 0.103 g. liter-1 in the control area with a slope of 20-40 percent in the autumn. Type of Coverage (skid trail and control area), the season and the interactions between the cover and the season statistically have significant effect on the sediment yield, but the slope and the interactions between the slope and cover, as well as the interactions between the slope and season have no statistically significant effect on the sediment yield. Duncan’s test showed that there was a yield statistically significant difference between sediment yeild in different seasons and the autumn had the highest sediment
mahbube hoseini; Ali Golkarian
Abstract
Resource management governing as one of the most valuable nature resource of watersheds with the involvement of local beneficiary to participatory management of water resources, one of the requirements of the water security program. So we considered social network analysis as an approach to analyzing ...
Read More
Resource management governing as one of the most valuable nature resource of watersheds with the involvement of local beneficiary to participatory management of water resources, one of the requirements of the water security program. So we considered social network analysis as an approach to analyzing the relationship between local stakeholders for sustainable management of water resources. The purpose of this study is study social network of local stakeholders using social network analysis in watershed of Kharve Olya of Neyshabur city. This study has been made based on trust and participant links and using quantitative and mathematical indicators in network macro-level (density, concentration, links reciprocity, transferability of links, the average geodesic distance). The results show that social capital degree based on trust and participant links was strong and stability and balance of network is evaluated at the upper limit that indicates a high level of mutual trust and participant among the local stakeholders. Also the correlation between trust and participant links based on QAP index was 66% and upward average. Results of mean geodesic distance index based on trust and participant link trust indicate trust and participant flow rate is from moderate to high degree. The results can be argued that high levels of social capital and unity among people lead to increase trust and participant flow rate among stakeholders so we can accomplish successful governing of water resources at the less expense and time.
somayeh dehdari; mehdi riasati; farhad fahkri; Morteza pozesh shirazi
Abstract
Understanding potential and capabilities in desert areas and Identification and introduction of plants compatible with those conditions, it is very important to modify hard and brittle conditions and forage production. In this study, to identify and introduce suitable pasture species for planting and ...
Read More
Understanding potential and capabilities in desert areas and Identification and introduction of plants compatible with those conditions, it is very important to modify hard and brittle conditions and forage production. In this study, to identify and introduce suitable pasture species for planting and establishment with the aim of restoring vegetation in Bushehr Province, the species of Cenchrus cilliaris, Cymbopogon oliveri, Panicum turgidum and Sporobolus arabicus were used. For this purpose, during the spring of 1394, the seeds of the studied species were collected and cultivated in the second half of 1395. The traits included altitude, percentage of viability, canopy percentage and forage production in year and plant deployment rate. Data collected in a randomized complete block design were analyzed by SAS software and the means of the collected samples were compared with Duncan multi-domain test. Results showed that there was a significant difference between the species in the measured factors. The species P. turgidum, C. oliveri and C. cilliaris were respectively identified as the best species in the climate conditions of the Dashti district in Kaki. S. arabicus specie in some traits, it could have a significant statistical significance but was not meaningful in terms of deployment and compatibility.
moslem dehdari far; Mohammad Faraji; Mohammad Salehi veisi; Jahangir Ehsani
Abstract
Data on the resistance of rocks to erosion and weathering and their voluntary ratings are key information in erosion and sediment studies. Despite the importance, rock resistance to weathering is not well studied in Iran and the conducted studies are more qualitative rather than quantitative. In this ...
Read More
Data on the resistance of rocks to erosion and weathering and their voluntary ratings are key information in erosion and sediment studies. Despite the importance, rock resistance to weathering is not well studied in Iran and the conducted studies are more qualitative rather than quantitative. In this study rock mass resistances of Asmari formation (limestone) and Fars formations including Mishian (marl limestone), Aghajari (Calcareous sandstone) and Gachsaran (anhydrite) were assessed using rock mass rating (RMR) method in Behbahan, Gachsaran, Deylam and Dehdasht regions. ANOVA and Tukey,s analysis of resistances of 81 collected rock samples showed there were significant differences (P<0.05) between geological formations in term of rock resistance. According to RMR rating, rock mass resistances were in order of Asmari limestone> Mishan limestone> Aghajari calcareous sandstone> Gachsaran anhydrite. Results also indicated there were no significant differences between rock resistances of Fars formations but rock resistance of Fars formations differed significantly from Asmari formation.
Roholah Zeynivand; Majid Ajorlo; Ali Ariapour
Abstract
This study aimed to investigate the effects of livestock grazing intensities (lenient, moderate, heavy and no-grazing) on herbaceous plant species composition and diversity (grasses and forbs) in understory of Quercus spp. and Pistacia spp. forest in Kebirkouh Mountain, Darehshahr city, Ilam Province, ...
Read More
This study aimed to investigate the effects of livestock grazing intensities (lenient, moderate, heavy and no-grazing) on herbaceous plant species composition and diversity (grasses and forbs) in understory of Quercus spp. and Pistacia spp. forest in Kebirkouh Mountain, Darehshahr city, Ilam Province, Iran. Vegetation sampling was carried out with randomized-systematic method at flowering time of the dominant plant species in April 2017. Within each quadrat, number of species, name of plants, density, life form and palatability class were recorded for herbaceous plants. Species diversity with the Simpson’s and Shannon-Weiner indices, species richness with Margalef and Menhinick indexes, and evenness with Peet and Sheldon indices were calculated in Ecological Methodology software version 6.1.4. The highest value of Simpson index for grasses and forbs was 0.972 (moderate grazing) and 96.95 (exclosure). Also, the highest value of Shannon index for grasses and forbs was 4.51 (heavy grazing) and 4.56 (heavy grazing), respectively. The highest richness of grasses and forbs was observed in grazed area with moderate intensity and no-grazing area, respectively. In the area without grazing, the richness of forbs was 4.4 and 2.75 according to Margalef and Menhinick indexes. The values of the Margalef and Menhinick richness indexes for grasses in grazed area with a moderate intensity were18 and 15 percent higher than the grazed area with heavy intensity. Peet and Sheldon evenness indexes were the highest for grasses and forbs in heavily grazed area and the lowest for grasses in the moderate grazing intensity and for forbs in the exclosure.
Hossein Sarvi sadrabad; Iman Islami
Abstract
Water is one of the major sources of development in countries and one of the greatest challenges of the present century, which can be the source of many of the positive and negative developments in the world, and in fact destruction of water resources is the destruction of the foundations of development. ...
Read More
Water is one of the major sources of development in countries and one of the greatest challenges of the present century, which can be the source of many of the positive and negative developments in the world, and in fact destruction of water resources is the destruction of the foundations of development. Researches has shown that improved management of conservation, exploitation and distribution of water resources is possible by reducing Governmental Entrepreneurship and stakeholders' participation and community participation through participatory management. Accordingly, social network analysis is considered as an approach to analyzing the relationships of local stakeholders for sustainable water resources management. The purpose of this research is to survey social network of local stakeholders using social network analysis in Sadr Abad village in Nodoushan catchment of Yazd. This research has been done on the basis of two connections of trust and participation using network level and subgroup level indicators. The results indicate that the degree of cohesion and social capital is moderate, and the stability and equilibrium of the network is also high, which indicates the high level of transmission in the relationships of trust and participation. Also, the correlation between the two connection of trust and participation, based on the QAP index, is 64 percent and it is appropriate and high level. Water management network in Sadrabad has the potential of greater cohesion and social capital, that prerequisite of it is to utilize the appropriate state of trust to increase participation.
Esmaeil Sheidai Karkaj; isa jafari; roghayeh jahdi
Abstract
Fires are one of the most important factors affecting natural ecosystems. This study was done in order to investigate the effects of fire on soil chemical properties, soil seed bank and vegetation cover in Yeke Bermagh, Highland ranegelands in the southern part of Golestan National Park. After determination ...
Read More
Fires are one of the most important factors affecting natural ecosystems. This study was done in order to investigate the effects of fire on soil chemical properties, soil seed bank and vegetation cover in Yeke Bermagh, Highland ranegelands in the southern part of Golestan National Park. After determination of control and burned area, sampling was done with 5 transects and 5 plots. Vegetation cover, density and production were recorded in each site. One plot was chosen for analysis of soil chemical properties and soil seed bank along transects. Sampling for seed soil bank determination was accomplished in two depths, 0-5 cm and 5-10 cm. In order to distinguish the differences between the two depths in each site, the independent t-test, and pair t-test were used. Comparison of soil properties in the two control and burned areas showed that pH, potassium, nitrogen, phosphors, carbon, EC and CEC in the burned area was more than control area. According to the results the amount of richness and diversity of seed bank in the control area was higher than the burned area. Furthermore, richness and diversity in the first depth was more than the second depth, in both areas.
Morteza Saberi; vahid karimian; Hamid Niknahad Gharemakhar
Abstract
Many regular visits were done to investigate the phenological stages of the plant in Zabol and Saravan habitats. Plant cover of the species was investigated by plot with 4 square meter along to 4 transect with 200 meters. To investigate their physicochemical properties of soil, soil sample were taken ...
Read More
Many regular visits were done to investigate the phenological stages of the plant in Zabol and Saravan habitats. Plant cover of the species was investigated by plot with 4 square meter along to 4 transect with 200 meters. To investigate their physicochemical properties of soil, soil sample were taken from 0-30 cm depth under the species and area without species. Forage quality index was analyzed by 4 replication on three phenological stages (vegetative, flowering and maturity stages). Results indicated that the first leaves of the species were initiated in March and August is the end of growing period. The average of canopy cover and density of Citrullus colocynthis had significant difference in the two regions (P<0.01). The rooting depth of this species was 207 and 123 centimeters in Zabol and Saravan habitats, respectively. The results showed that the electrical conductivity, carbon and organic matter under the studied species were significantly higher than the control area. The results of soil analysis under the species of two habitats also showed that sand, silt, acidity, lime and organic carbon content were significant at 5% level (p <0.05) and organic matter was significant at 1% level (p <0.01). Also, the average of sand, acidity, organic creatinine and organic matter of Zabol habitat was higher than Saravan, but the amount of silt and lime in the plant cover was higher in Saravan than that of Zabol.
Delaram Ziaei; Rafat Zare Bidaki; Aliasghar Besalatpour
Abstract
Knowing the amount of runoff and sediment generated from different lands is an important step in land use management. Since it is not always possible to measure these values, modeling parameters, will be a way to achieve watershed comprehensive management. Beheshtabad watershed in Chaharmahal & Bakhtiari ...
Read More
Knowing the amount of runoff and sediment generated from different lands is an important step in land use management. Since it is not always possible to measure these values, modeling parameters, will be a way to achieve watershed comprehensive management. Beheshtabad watershed in Chaharmahal & Bakhtiari province with different land uses such as range land, agriculture, gardens and urban area is an important part of Northern Karun Basin. In order to simulate the amount of runoff and sediment generated in different land uses, SWAT model was used. Discharge and sediment data of weather and hydrometric stations located in the area was used for sensitivity analyses and then to calibrate and validate model by SUFI-2 algorithm. NS and R² coefficients obtained for runoff calibration are respectively 0.69, 0.71 and for runoff validation are 0.65, 0.67 and for sediment are 0.72, 0.73 in calibration, and 0.66, 0.71 in validation, that confirmed model ability to accurately estimate of flow, runoff and sediment in the study area. The results showed that dry farming lands with average runoff and sediment of 190 mm, 24.5 tons per hectare per year respectively, has the highest and gardens with an average of 80 mm runoff has the lowest sediment yield of 1.63 tons per hectare in the year.
Feridon Ghadimi; Pegah Javadi Sharif
Abstract
The mixing of freshwater and salty water in saline playas, high dissolution of calcareous stones, agricultural activities, industrial effluents and municipal and rural waste landfills are the most important sources of groundwater threats that threat human health. In this study, 46 water samples were ...
Read More
The mixing of freshwater and salty water in saline playas, high dissolution of calcareous stones, agricultural activities, industrial effluents and municipal and rural waste landfills are the most important sources of groundwater threats that threat human health. In this study, 46 water samples were taken from Arak plain and their physical and chemical variables were determined. Multivariate statistical analysis including stage factor analysis on the physical, chemical and chemical variables of groundwater in Arak aquifer have an important role in distinguishing between different pollutants in the region. The stage factor analysis gave five factors in the hydrochemistry variables of Arak aquifer. In the first factor, the EC, TDS, Cl, SO4, Ca, Mg and Na variables have a natural origin, which is the mixing of saline water from Mighan playa and freshwater aquifer. In the second factor, HCO3 is a natural origin due to the dissolution of limestones in southern Arak and HNO3, originating from humans and as a result of the influence of urban absorption wells and agricultural activities. The origin of the elements in factor three and four, mainly Zn, Cu, Fe and Mn, is mainly due to industrial activities and landfill, and F, is also due to agricultural activities, i.e, the use of phosphate fertilizers. This study also showed that stage factor analysis is a suitable method for separating source of contaminants. Therefore, appropriate measures should be taken by organizations and companies to control human pollution from sources such as Arak municipal wastewater, agricultural and industrial wastewater.
Mehrnoosh Ghadimi
Abstract
Given the time/cost inefficient nature of land mapping for monitoring of the changes in the earth dams’ body across the world, the Radar Interferometry is introduced here as a modern alternative method. In this study, to investigate the changes in the Taleqan dam’s body, we employed the GMTSAR ...
Read More
Given the time/cost inefficient nature of land mapping for monitoring of the changes in the earth dams’ body across the world, the Radar Interferometry is introduced here as a modern alternative method. In this study, to investigate the changes in the Taleqan dam’s body, we employed the GMTSAR software and processed 68 Sentinell- A images taken in the time period of 2014-2018. Additionally, utilizing the radar interferometry in the short range, the time series was determined. The time series results implied that the maximum dam subsidence is 3 mm/y along the line of sight. To justify the changes in the Taleqan dam’s body, some studies were carried out on the rip rap of the dam’s body. The obtained results implied that the changes have been caused by erosion and weathering. Due to undesired diffusion coefficient and low resistance of the stones with external volcanic and reolithic structure, such material collapsed under the influence of atmospheric and temperature factors, leading to displacement in the downstream. The performed investigations implied capability of the radar interferometry in monitoring of the earth dams and critical structures and providing information that can play a vital role in analysis of the dams’ behavior and completion of the precise tools measurements.
mohsen kazemi; sadegh naji; Sadat Feiznia; Hassan Khosravi
Abstract
One of the strategies to achieve sustainable management of lakes and wetlands is change detection of lakes, wetlands and their surrounding landuses during the specific time periods. In this research, the satellite images from 1381 to 1394 applying geometric and atmospheric corrections were used in order ...
Read More
One of the strategies to achieve sustainable management of lakes and wetlands is change detection of lakes, wetlands and their surrounding landuses during the specific time periods. In this research, the satellite images from 1381 to 1394 applying geometric and atmospheric corrections were used in order to monitor the changes of the Maharloo Lake level and its surrounding lands Image subtraction techniques, the principle component analysis (PCA) and fuzzy logic were used for providing the maps of landuse changes and drastically changes. The obtained results of Maharloo landuse changes showed that the lake water level has decreased 78 percent during 1381 to 1394. Reducing the lake water level, the landuses of bare and saline lands increased 46 and 58 percent respectively. The obtained results of the drastic changes showed that 82% of the changes have had the intensity between 50-100 percent. The most intensity of the changes with reduction of 22 percent was related to water body of Maharloo. The reduction of Maharlu Lake water level have different consequences therefore management planning is necessary to prevent its ecosystem degradation and Risks of reduced water levels in recent years.
Abdolhosain Mohammadi; Reza Ghazavi; rohollah Mirzaei; Hamidreza Naseri
Abstract
Rainfall is one of the most important factors affecting vegetation cover. Fluctuation and year-to-year variation of rainfall always affect vegetation cover patterns. The main aim of this study was to investigate and modeling the effects of rainfall changes on the variation of the vegetation cover in ...
Read More
Rainfall is one of the most important factors affecting vegetation cover. Fluctuation and year-to-year variation of rainfall always affect vegetation cover patterns. The main aim of this study was to investigate and modeling the effects of rainfall changes on the variation of the vegetation cover in the Meyghan basin in Arak province using MODIS satellite images. NDVI, DVI, RVI and EVI indices were used to manifest vegetation covert variations linear and nonlinear relationship between vegetation cover changes and rainfall investigated simultaneously (May), with one and two month delay (April and March) ) during the statistical period of 2000-2017. The rainfall trend analysis was done using non-parametric Mann-Kendall test. According to the results, the minimum rainfall during the 18-year period was increased. Between vegetation indices, NDVI index showed the maximum and the average incremental trend. Between precipitation and vegetation, third-order non-linear relationship was stronger than linear, quadratic, power, logarithmic and exponential. The maximum correlation between DVI index and rainfall was obtained for synchronous times, while, the maximum correlation was observed between NDVI index and precipitation. The study with two month delay showed that the maximum correlation (0.52) was between the RVI index and precipitation. Vegetation modeling using simultaneous rainfall and delay of up to two months showed that the indices of DVI, RVI and EVI provided the best regression relationship at the same time, while the NDVI index had the best regression relationship with rainfall of two months ago.
Aliakbar Nazari Samani; mahmoud samadi; arash malekian
Abstract
For developing of water resources a lot of different factors (such as: geological structure, faults, joints and geomorphological metrics) are important. This research tried to assess the effects of geomorphology on karstic water resources in central Elburz region. Geomorphometrics indices were prepared ...
Read More
For developing of water resources a lot of different factors (such as: geological structure, faults, joints and geomorphological metrics) are important. This research tried to assess the effects of geomorphology on karstic water resources in central Elburz region. Geomorphometrics indices were prepared in the form of separate layer in GIS and RS and were overlaid on the springs distribution map. To assess the relationship between springs frequency, discharge and geomorphology statistical analysis such as correlation and factor analysis were done. Results indicate a close relation between spring occurrence and hillslope curvature and TPI. Also the Pearson correlation coefficient of elevation and lineament density and drainage density was significant (P<0.01). According to results the discharge of springs are directly related to drainage density and indirectly related to elevation and lineament density. Moreover the fetor analysis on 17 variables revealed that the first six components had Eigen value of more than 1 and 73.5% of total variance was explained by them. Result indicated that for future developing such a geomorphology characteristics can give suitable information of water resources.
roya vazirian; Ali Akbar Karimian; Alireza Afshani; Mohammad-Taghi Dastorani
Abstract
In Collaborative management of arid regions, it is necessary to analyze the social relationships between farmers. The purpose of this study was to evaluate and analyze the social network of farmers in trust links and to participate in irrigation, marketing and cultivation activities in three villages ...
Read More
In Collaborative management of arid regions, it is necessary to analyze the social relationships between farmers. The purpose of this study was to evaluate and analyze the social network of farmers in trust links and to participate in irrigation, marketing and cultivation activities in three villages of Aryan, Hareth Abad and Robat Sarpush in Sabzevar. For this purpose,in the firstusing with qualitative studies of survey approach,direct observation method and target population interview were identified. Then, the quantitative network analysis method, four important indices consist of "density", "reciprocity", "transitivity" and "average geodesic distance" in the links of trust and participation in agricultural activities of the farmers' network were evaluated. According to the results, the density of the four transplants was higher in Aryan village than the other villages, which is indicating more social cohesion in this village. The results of reciprocity and transitivity indexed in the studied links show more balance, equilibrium and stability of the network in Aryan village than the other villages, thus there is more social capital in this village. The average geodetic distance results also indicate the most favorable geodetic distance among the farmers in Aryan village. Increasing the cohesion and solidarity of these villages will speed up the flow of information and exchange, as well as increase social capital in them, and will help people to coordinate and access each other with less cost and time. Therefore, reinforcing trust and social participation is essential for increasing social capital as a necessity for participatory management
