Fatemeh Einloo; Mohammad Reza Ekhtesasi; Mehdi Ghorbani; Parviz Abdinejad; Reza Anjomshoaa
Abstract
One of the integrated water resources management requirements based on participatory management planning is identification and analysis of key stakeholders. Identifying structural aspects of organizational stakeholder's network can be evaluated using social network analysis and their position and role ...
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One of the integrated water resources management requirements based on participatory management planning is identification and analysis of key stakeholders. Identifying structural aspects of organizational stakeholder's network can be evaluated using social network analysis and their position and role for inter-organizational integration and coordination in water resources management can be determined. In this study, using social network analysis method, stakeholders related to participatory governance of Abhar plain water resources, including 20 organizational stakeholders were analyzed and policy indicators were evaluated at the level of the network of organizational stakeholders. Indices of density, size, reciprocity, transitivity, centralization and geodesic distance in network of relationships at the macro level, core-peripheral index in the middle scale and centrality indicators at the micro scale of network were examined. Rate of network density index is moderate and according to index of reciprocity, moderate amount of bilateral and reciprocal relations among organizational actors, cohesion and organizational capital are assessed as moderate. According to transitivity index, stability and balance of information exchange network is low. Analysis of core-periphery index of stakeholder's network shows a higher density of links and greater organizational cohesion among central organizations compared to peripheral subgroup and amount of information exchange between central and peripheral subgroups was evaluated as moderate. Based on centrality indicators, geometric position of each actor in network was determined. For decision-making, planning, policy-making and participatory governance of water resources in Abhar Plain, key and effective organizations and political forces, as well as organizations with low power and marginalized, were identified.
Soheila Pouyan; Mohammad Zare; Mohammad Reza Ekhtesasi
Abstract
Dust event is one of the common and destructive phenomenon in arid and desert regions. This phenomenon has negative impacts on human life and environment. Dust storms, in addition to soil loss, can cause and aggravate health problems, food production reduction, economical damages into the industrial, ...
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Dust event is one of the common and destructive phenomenon in arid and desert regions. This phenomenon has negative impacts on human life and environment. Dust storms, in addition to soil loss, can cause and aggravate health problems, food production reduction, economical damages into the industrial, agricultural and communication sections. Therefore, accurate investigative of this phenomenon is necessary. The aim of this research was regional analysis of dust storm index (DSI) in 44 meteorological stations of Iran. At first stage, the dust storm index for each station was calculated using hourly dust data. Next, monthly averages of dust storm index (DSI) were used for regional analysis using linear moments approach. Based on regional analysis, the study area is divided to six homogeneous dust storm index regions. Pearson Type III (PE3) and Generalized Logistic (GLO) distribution models were the best regional distribution models for 1, 4, 5, 6 homogeneous regions, and 2, 3 homogeneous regions, respectively. Estimation of the dust storm index and its regional analysis can be used in many environmental studies, decision making and management processes in relation to combating desertification and dust storms.
hamide afkhami; azam habibi pour; mohammad reza ekhtesasi
Abstract
Evaporation is considered one of the key climatic variables, especially in arid regions and evaporation losses is one of the important issues in irrigation and water resources management in these areas. Therefore, it is important being aware of the amount of evaporation and its modeling, as one of the ...
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Evaporation is considered one of the key climatic variables, especially in arid regions and evaporation losses is one of the important issues in irrigation and water resources management in these areas. Therefore, it is important being aware of the amount of evaporation and its modeling, as one of the most important hydrological variables in agricultural research and water and soil conservation. In recent decades, artificial intelligence techniques have proven high capability and flexibility to estimate and predict nonlinear phenomena. In this study, three important data mining techniques including Artificial Neural Network, Active Neuro-Fuzzy Inference System and Regression Decision Tree were used for predicting evaporation. For this purpose, 8 climatic variables (Minimum average temperature, average maximum temperature, average temperature, sunshine hours, wind speed, wind direction, relative humidity and evaporation averages) were employed in this study. The results showed three models are able to predict evaporation for 12 months after. Finally among the used models, ANN showed better performance with coefficient efficiency of 0.97 and RMSE of 5.1and ME of 0.48. Also, The results showed that there is not significant difference in simulation results to predict the evaporation between two scenario, original data and normalized data.
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.
Alireza Motevali; Ali Talebi; Mehrdad Safaei; Mohammadreza Ekhtesasi
Abstract
Landslide is one of the most important geological phenomena in northern slopes of Iran (Alborz) which causes considerable damages gradually. In the last few years, due to unfavorable changes in land uses and increasing degradation of pastures, forests and farmlands as well as implementation of inappropriate ...
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Landslide is one of the most important geological phenomena in northern slopes of Iran (Alborz) which causes considerable damages gradually. In the last few years, due to unfavorable changes in land uses and increasing degradation of pastures, forests and farmlands as well as implementation of inappropriate development projects in areas prone to landslides, geology formation prone to landsliding, rainfall rate and steep slopes, the occurance of this destructive phenomenon has constantly increased. In this research, landslides which occurred around Sari-Kiasar road were investigated using physically based models i.e. SINMAP and SHALSTAB and the stability map of the region was determined applying these models. First, the physical and mechanical properties of soils in 13 points were measured and evaluated by 56 landslide points. The results of field studies, laboratory samples, running models and data analysis showed that these models (SINMAP and SHALSTAB) have success rate equal to 87.3 % and 69.5%, respectively for predicting the slope instability in ChaharDonge region. This means that the SINMAP model has more efficiency than SHALSTAB model for slope stability analysis.
mohamadreza fazelpour aghdaei; hosein maleki nezhad; mohammad reza ekhtesasi; jalal barkhordari; Asghar Zarea Chahooki
Abstract
Given the widespread distribution of flood water spreading areas and variety of main effective parameters in their design and implementation, assessment of the performance of system components located in different areas of the country is necessary so that optimal patterns can be achieved. This research ...
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Given the widespread distribution of flood water spreading areas and variety of main effective parameters in their design and implementation, assessment of the performance of system components located in different areas of the country is necessary so that optimal patterns can be achieved. This research was done to assess the impact of the flood water spreading projects on soil characteristics in Yazd (Bafg, Herat and Mehriz flood spreading projects). To this end, in the first to the third spreading basin of projects and three a control sites were selected. Then, 99 soil samples in profiles were collected at five depths and physical and chemical properties were studied in the laboratory. Statistical analysis was performed by independent t-test. The results showed physical and chemical properties of soil is not significantly different from controls in Bafgh flood water spreading projects. In Herat, some parameters such as Electrical Conductivity, pH, Calcium and Potassium in the limited depths was significantly different but in Mehriz, most chemical parameters showed significant difference and decreasing trend. The results showed water infiltration and leaching of soil in the Mehriz area was more than others, while less in Herat and the least in Bafg.
Asghar Mosleh arany; Hamid Azimzadeh; Mohammad Reza Ekhtesasi; Neda imantalab; Ali Dolati
Abstract
This study aimed to investigate morphological changes of Capparis deciduas and C. spinosa and their effects on nebkha formation. In order to examine the morphological changes of these plants, nine C. spinosa nebkhas of varying ages were randomly selected and size and number of adventitious roots, number ...
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This study aimed to investigate morphological changes of Capparis deciduas and C. spinosa and their effects on nebkha formation. In order to examine the morphological changes of these plants, nine C. spinosa nebkhas of varying ages were randomly selected and size and number of adventitious roots, number of shoot and buds were counted. Results showed that the dead and green parts of C. spinosa in nebkha were significantly more than control plants. These showed that nebkha in C. spinosa stimulated growth by increasing bud and shoot at first and then there was a steady mortality when the volume of nebkhas increased. In C. deciduas, nebkha caused stimulation of adventitious roots in buried shoots. Increasing nebkha volume did not increased the number of shoots and buds in C. decidua. Control plants did not produce adventitious roots. Formation of nebkha in C. decidua happened in two ways. In the first, C. decidua plants in middle age produced root stock in base of stems. Root stocks continued to grow, trap sand, and form nebkha. Root stock in nebkha produced adventitious root. In consecutive years root stocks continued to grow, trap sand, and form larger nebkha. In contrast, growth of main stems stopped and they were finally dried. C. decidua also formed nebkha like C. spinosa in the second way. It is concluded that C. decidua stimulated better adaptive morphological changes compared to C. spinosa in facing nebkh formation.
