A. Salajegheh; A. Fathabadi; M. Mahdavi
Volume 62, Issue 1 , June 2009
Abstract
Rainfall-runoff is one of complex hydrological processes that is affected by a variety of physical and hydrological factors. In this study statistical method ARMAX model, neural network, neuro-fuzzy (ANFIS subtractive clustering and grid partition) and two hybrid models of this methods were used to simulate ...
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Rainfall-runoff is one of complex hydrological processes that is affected by a variety of physical and hydrological factors. In this study statistical method ARMAX model, neural network, neuro-fuzzy (ANFIS subtractive clustering and grid partition) and two hybrid models of this methods were used to simulate rainfall-runoff and prediction of streamflow. In each method optimum structure was determined then, streamflow forecasted using the best model. The results showed that hybrid methods have better application than single models and artificial intelligent has better application than linear ARMAX model due to nonlinearity of rainfall-runoff process. In this study all methods showed relatively suitable application but ANFIS method with subtractive clustering is suggested for modeling rainfall-runoff and streamflow prediction.
Abdolmotalleb Rezaei; Seyyed Mahmoud Hosseini; Ali Asadi
Abstract
Social network analysis used to study the relationship between stakeholders and actors in natural resource management has become a scientific approach. The purpose of this study was analysis of Information Exchange Network among organizations engage in the sustainable management of natural resources. ...
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Social network analysis used to study the relationship between stakeholders and actors in natural resource management has become a scientific approach. The purpose of this study was analysis of Information Exchange Network among organizations engage in the sustainable management of natural resources. Results of Social Network Analysis revealed that there is weak Relationship among organizations about information exchange in sustainable natural resource management and access to information in this network is very hard and there is medium communication potential among organizations. Also in information network of the organizations, Agricultural organization had high power in the whole network. University, Agricultural organization and Research Center for Agriculture and Natural Resources have important role in facilitating of information exchange. Analysis of regularity process and its relationship with information exchange network revealed that forests, range and watershed management organization has more power than other organizations.
Amin Zoratipour
Abstract
Abstract
Estimation of fine suspended load rivers is important in designing reserves, transition volume ofsediment, and estimating lake pollution. Thus, some methods are needed for determining damagescaused by sedimentations in environment and determining its effects on the watersheds. There aremany ...
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Abstract
Estimation of fine suspended load rivers is important in designing reserves, transition volume ofsediment, and estimating lake pollution. Thus, some methods are needed for determining damagescaused by sedimentations in environment and determining its effects on the watersheds. There aremany methods for estimating suspended load, one of these methods that solves the problems ofsediment discharge and can predict it is using Neuro fuzzy or ANFIS (Adaptive Network FuzzyInference System), and ANN (Artificial Neural Network) methods. These make a function betweensediment and simultaneous discharge by use of different algorithms. The goal of this research iscomparing the effectiveness of Neuro fuzzy, neural network artificial and statistical methods forestimating suspended load river in Glinak station of Taleghan Basin. It was found out thatsuspended load estimations of Nero fuzzy method with MAE 1006 ton/day, and correlationefficiency (R) 77%, RMSE 2621 ton/day and Nash-Sutcliff error (NS) 0.51 is better than NeuralNetwork Artificial and Statistical methods and Artificial Neural Network method rather thanStatistical Method are more proper. Also, contracting both neural networks artificial to fuzzy lawscan be illustrated better than other methods, variation of sediment Load River. One more merit ofthis method is that it is not sensitive to few errors in early statistical data and this fact enables betterestimation of neural network model in comparison with statistical model. Finally, Neuro fuzzymethod works better as the percent of train data to test data increases.
Amin Zarratipour; marjan firoozinejad; Khalil Delfan Hasanzadeh
Abstract
Abstract The phenomenon of climate change and global warming and its impact on different ecosystems Needed extensive studies. For this purpose, was done Study of the efficiency of thermal bands and land use changes in determining the surface temperature index using a separate window algorithm in the ...
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Abstract The phenomenon of climate change and global warming and its impact on different ecosystems Needed extensive studies. For this purpose, was done Study of the efficiency of thermal bands and land use changes in determining the surface temperature index using a separate window algorithm in the Bandar-e Emam Khomeyni of Khuzestan province by Landsat 8 satellite imagery. Based on this, was used vegetation index (NDVI) for band ratio between the red and near infrared bands to prepare the LST map and were used four seasonal images in 2016-2017 years. The results of the comparison of the two thermal bands showed that the thermal bond 11 is higher accuracy than the thermal bond 10 (RMSE = 3.6 for the band 11 and RMSE = 4.4 for the band 10) because the wavelength of it is higher. Also, the estimation of the comparison of satellite imagery data with ground truth showed a high accuracy (R2 =0.9). Comparing the temperature of the users was determined that the industrial and urban areas more effective on increasing LST than the vegetation and water areas. Base on bands ratio between near and red infrared bands showed that the vegetation index decreased with increasing temperature. So, the lowest amount of vegetation was estimated in August (-0.42) and the highest was in October (0.35).
Gholm Reaza Rahi; A Kaviyan; K Soleimani; H Pourghasemi
Abstract
Creating a gully is a reaction to the geomorphologic conditions, this type of erosion extends over a wide range of environments, and the threshold of topography is related to the slope and drainage level and Controls the position and expansion of gullies in different uses. The slop-area equation as a ...
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Creating a gully is a reaction to the geomorphologic conditions, this type of erosion extends over a wide range of environments, and the threshold of topography is related to the slope and drainage level and Controls the position and expansion of gullies in different uses. The slop-area equation as a relationship between the slope and the upstream area of the watershed in any area will in part help predict gully erosion. The above relationship has been influenced by several factors including environmental conditions (climate, lithology, soil type), the type of land use, and the type of effective mechanisms for the creation and expansion of the gully (surface flow, sub-surface flow, dissolation, and piping), and the type of method used for extraction of slope - area is located. And this is the simplest formula used by two parameters to predict gully erosion. The results show that the value of the relationship between -0.233 and -0.205 was obtained. The equation for agricultural use was equal to Y = 5.7426X-0.205and for the pasture use equal to Y = 10.653X-0.233. In this equation, the power can be close but the coefficient of the equation is different. Gully erosion of the whole hinterland (farmland, agriculture) is expanding. The threshold of topography indicates a negative relationship between land area and slop in different kind of agricultural and rangeland. By reducing the slope, more area is needed for the development and expansion of the gully, and most of the gully is due to surface runoff.
Davood Hasanabadi; Ahmad Haj-Alizadeh; Masood Heidarvand
Abstract
Social capital is one of the main factors for local sustainable development and social empowerment. The objective of present research is social capital assessment to achieve local sustainable development in Se-Qaleh city, Sarayan district in South Khorasan province, where the international RFLDL project ...
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Social capital is one of the main factors for local sustainable development and social empowerment. The objective of present research is social capital assessment to achieve local sustainable development in Se-Qaleh city, Sarayan district in South Khorasan province, where the international RFLDL project was implemented. In this research, the level of trust and cooperation ties in the stakeholder’s network was assessed in two stages i.e. before and after implementing the RFLDL project using network analysis questionnaires based on observation and interview with all stakeholders and also through the measurement of network analysis indicators including; density, reciprocity, transitivity and average of geodesic distance. The results of this study show the amount of trust and cooperation or social capital before implanting the RFLDL project was in moderate status but it increased post project implementation. The rate of trust and cooperation exchanges among people after implementing the project grew higher than before. Implementing this project as well enhanced the unity among the people.
Morteza Dehghani; Hosein Ghasemi; Arash Malekian
Abstract
Nowadays, watershed management practices are undertaken based on selective criteria and/or a specific purpose such as a decrease in flood risk, soil erosion and the like. In this respect,fuzzy logic has the ability to manage a wide range of options for decision making. This researchaimed to use the fuzzy ...
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Nowadays, watershed management practices are undertaken based on selective criteria and/or a specific purpose such as a decrease in flood risk, soil erosion and the like. In this respect,fuzzy logic has the ability to manage a wide range of options for decision making. This researchaimed to use the fuzzy logic theory to priorities watershed management practices consideringtime and budget constraints in catchments with high sediment production and flood risk. Thisresearch was carried out in the Foorg watershed of Darmian town with an area of 11137 ha. Allparameters related to soil erosion and flood risk were determined using the standard methods.Fuzzy score for each mentioned factor was then determined. Finally watershed managementpractices using the fuzzy theory and GIS were prioritized.
Tahereh Sadeghi Shahrakht; Mohammad Jankju; Mansour Mesdaghi
Abstract
Rangeland shrubs may provide mechanical facilitation on their understory plants, by protecting themagainst the livestock grazing. However, such a facilitation effect may vary depending on the rangelandutilization rate. In a field research, mechanical facilitation of rangeland shrubs was compared in ahighly ...
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Rangeland shrubs may provide mechanical facilitation on their understory plants, by protecting themagainst the livestock grazing. However, such a facilitation effect may vary depending on the rangelandutilization rate. In a field research, mechanical facilitation of rangeland shrubs was compared in ahighly grazed, a moderately grazed and an enclosure site; in an arid rangeland, Kakhak, Gonabad,Iran, during spring to summer 2011. Twenty line transects were established in various directions andslope aspects. Forage production was measured by clipping method within the paired plots, i.e. underthe canopy of nursing shrubs and their nearby open areas. In the enclosure site, forage production wassimilar under the canopy of shrubs and in open areas, whereas in the highly and moderately grazedsites there were more forage under the canopies. These results indicate increases in mechanicalfacilitation of rangeland shrubs by increasing the grazing intensity. The mechanical facilitation wasalso varied depending on the life forms of understory species. In the enclosure, the greatest facilitationwas on annual forbs, whereas in the highly grazed site it was on perennial grasses. Results of thisstudy show important role of rangeland shrubs on preserving understory forage plant against theintense livestock grazing.
Alirostam Khanizadeh; Reza Erfanzadeh; Reza Siahmansur
Abstract
The aim of this study was to quantify the response of Bromus tomentellus, Hordeum bulbosum and Agropyron trichophorum to continuous grazing of sheep in semi-arid rangelands of Lorestan. In two areas, grazed and ungrazed, 4 transects of 200 meters were established and 10 random points were selected along ...
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The aim of this study was to quantify the response of Bromus tomentellus, Hordeum bulbosum and Agropyron trichophorum to continuous grazing of sheep in semi-arid rangelands of Lorestan. In two areas, grazed and ungrazed, 4 transects of 200 meters were established and 10 random points were selected along of each transect and at each point the nearest plant considered for further study. Morphological traits of each selected plant were measured i.e. height, internode distance, root length, root weight, production and mass. After reviewing the data normalization, the averages between grazed and ungrazed were compared by non-paired t-test. The effect of livestock grazing on height, shoot internode, length and root weight, biomass and yield of H. bulbosum and A. trichophorum were significant. The mean weight of H. bulbosum in the ungrazed and grazed areas was 117.1 gr and 16.1 gr, respectively, and the height of A. trichophorum was 525.1 mm in the ungrazed and 334.7 mm in the grazed areas, respectively. Grazing of livestock had no significant effect on the height and internode distance of B. tomentellus (p>0.05). Animal grazing significantly increased root length of 58.35 mm in B. tomentellus. In general, the results of this study showed that different species of plants exposed different reactions and trade-off against grazing depending on the type of plant species. Knowledge about of the morphological changes of plant species against grazing can greatly help us for the management of sustainable grazing in the rangelands.
M Ghorbani; A.A Mehrabi; M Servati; A.A Nazari Samani
Volume 63, Issue 1 , June 2010, , Pages 75-88
Abstract
Nowadays, population growth and on the other hand resources limitations astonish authorities. Population changes cause variation in economic activities and land use changes. As a whole, overusing, improper land use and human disturbances over natural resources make environmental imbalances worse. In ...
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Nowadays, population growth and on the other hand resources limitations astonish authorities. Population changes cause variation in economic activities and land use changes. As a whole, overusing, improper land use and human disturbances over natural resources make environmental imbalances worse. In recent decades, we have seen land use changes in Taleghan basin. Land use changes were produced by many factors, e.g. in abandoned lands, some parts of the region have been converted to residential areas and constructions. Since one century before, because of vicinity to population centers like Tehran and upland condition, this region has been a suitable place for recreation of travelers. Also one of the most important factors has been changed in population which has occurred in Taleghan. So that the statistical information shows substantial decrease in villages population in Taleghan. Similar to the, other regions in Iran, landuse changes especially in rangelands, is an important subject in Taleghan too. This paper tries to illustrate the relationship between population and land use changes in the given region of study and to detect the land use changes in a 15-year period. For determining the landuse, we used geographic information system and statistical methods, remote sensing also landSat images for 1987 and 2001 together. Population size were gained and analyzed for computing the population growth rate. According to what we concluded, in abandoned lands in given region of study the growth rate was positive and in other word, it increased and for other land uses this rate was negative together with negative increasing in all villages, therefore the population decreased. The villages of this region according to their magnitude of reduction in population growth and abandoned lands are: Gateh deh, Narian, Noviz oliya, Dizan, Jovestan, garab, Orazan, Nesa Bala, Mehran, Khachireh, Drapy. Thus, great number of settlers during these years migrated and the population decreased and following this trend, great area of rangelands (37.88%) which has already converted to rain-fed lands, has emerged in the form of abandoned lands in this region. In Gateh deh village, the area of rangelands had the maximum reduction and on the contrary, abandoned lands had the maximum amount of growth. Finally, it could be inferred that, there is a logical relationship between population growth and the area of abandoned lands.
Golnaz Kheradmand; Ali Ariapour; Hamidreza Mehrabi
Abstract
Honey bee husbandry is one of the multipurpose uses of rangelands that it affects by biotic and abiotic factors that investigated in this study for Sarab-Sefid rangeland of Borujerd County. To evaluation of honey bee husbandry suitability used FAO model include four main model plant cover, weather, topography ...
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Honey bee husbandry is one of the multipurpose uses of rangelands that it affects by biotic and abiotic factors that investigated in this study for Sarab-Sefid rangeland of Borujerd County. To evaluation of honey bee husbandry suitability used FAO model include four main model plant cover, weather, topography and distance. Four categories used such as S1 (Suitable), S2 (medium Suitable), S3 (low Suitable) and N (None Suitable). Results show that there is no suitable in April for honey bee husbandry in any part of the area. Also according to mountainous and cold weather in spring and summer subsequently short time to plants growth and according to more grasses families of plants whole area was not in class S1. Honey bee husbandry model in April-May it falls in S3 and N classes with 1152.67 (19.66%) and 4711.76 (80.43%) hec respectively. In May-June months 883.42 (15.06%), 2002.86 (34.15%) and 2978.15 (50.79%) hec falls in S2, S3 and N classes respectively. This result was obtained for June-July so that 799.81 (15.06%), 2437.79 41.57%) and 2626.81 (43.37%) hec falls in S2, S3 and N classes respectively and for July-August-September 799.81 (15.06%) hec in S2 class, 2554.54 (43.56%) hec in S3 and 2509.65 (41.38%) hec fall in N class. Consequently, best time to honey bee husbandry is May to September months.
M. H. Davoudi
Volume 62, Issue 2 , October 2009, , Pages 231-245
Abstract
Stabilization of river terraces and natural soil slopes in rangelands by means of tree roots as a reinforcement agent is an environmental adopted method which needs to be developed. In this research a series of tests was carried out on soil blocks containing willow roots and without roots using a large ...
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Stabilization of river terraces and natural soil slopes in rangelands by means of tree roots as a reinforcement agent is an environmental adopted method which needs to be developed. In this research a series of tests was carried out on soil blocks containing willow roots and without roots using a large scale in situ direct shear test apparatus. The results were analyzed based on direct shear theory to calculate the cohesion and internal friction angle of rooted and non-rooted soil. The results reveal that in spite of a slight decrease of 8% in the internal friction angle, the appearance cohesion of lean clay soils increase significantly up to 130%. The results of this research are presented in forms of linear and logarithmic relations between increased shear strength and root density at different depths of soil.
Hamidreza Moradi; Alireza Sepahvand; Parviz Abdolmaleki
Abstract
More than 30% of Iran's land is formed from mountainous areas. So each year, landslides cause damages to structures, residential areas and forests, creating sedimentation, muddy floods and finally deposit the sediments in reservoir dams. Therefore, for preventing of this damages and expressing the sensitivity ...
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More than 30% of Iran's land is formed from mountainous areas. So each year, landslides cause damages to structures, residential areas and forests, creating sedimentation, muddy floods and finally deposit the sediments in reservoir dams. Therefore, for preventing of this damages and expressing the sensitivity rate of hillslopes, landslide hazard zonation is considered in prone areas. The purpose of this study is to determine the optimal structure of artificial neural network with different numbers of input factors for the landslide hazard zonation in the Haraz Watershed. First, the number of optimal epochs was determined to prevent network overlearning with trial and error method. Then, 14 neurons were determined in the hidden layer. Finally, the number of neurons was changed from 1 to 9 in the input layer. According to the obtained results, with increasing the number of neurons in the input layer, efficiency of Artificial Neural Network improved for landslide susceptibility mapping. In this research, nine neurons in the input layer, 14 neurons in the hidden layer and one neuron in the output layer were selected as the optimal structure. Root Mean Square Error and Descriptive Coefficient (R2) were equal to 0.051 and 0.962, respectively and the accuracy of landslide hazard zonation map was equal to 92.3%. Meanwhile, the results showed that about 35.14, 26.73, 14.59, 9.88, and 13.63 percent of all studied areas are located in stable, low, moderate, high and extremely hazardous areas, respectively.
Behzad Rayegani; Gholamreza Zehtabian; Hossein Azarnivand; Seyed Jamalodin Khajedin; Seyed Kazem Alavipanah
Abstract
Arid and semi-arid areas, due to the sensitive, have variable ecosystems, so continuous assessment and monitoring of the environment is required for most of managerial and adjustment practices. Vegetation is one of the most important assessment tools and used as a criterion for evaluation and monitoring ...
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Arid and semi-arid areas, due to the sensitive, have variable ecosystems, so continuous assessment and monitoring of the environment is required for most of managerial and adjustment practices. Vegetation is one of the most important assessment tools and used as a criterion for evaluation and monitoring of ecosystem functions. In this study, for the first time in the country, we have evaluated status of vegetation in a desert area by the method provided by the Land Degradation Assessment in Aridlands as one of the last instruction of the vegetation status assessment. The model uses 16 different indicators to assess vegetation status: Total Bare Soil; Bare Spots; Litter cover or Surface organic matter; Vegetation Vigour; Proportion of perennial species; Proportion of Useful Species; Proportion of each vegetation strata; Species that decrease with grazing pressure; Species that increase with grazing pressure; Poisonous plants; Alien Invasive or proliferous weed species; Pest damage; Damage due to diseases; Bush /shrub encroachment; Utilization (Deforestation); Biomass decline. After running the model in the desert rangelands of East and compared the results with the reality, we found this model at least for the desert area, have very good performance.
Gholam Ali Heshmati; Diana Askarizadeh; Rahim Forouzeh
Abstract
In order to determine the diet of Dalagh sheep, winter rangeland of Gomishan plain was selected. After delineating of the grazingland territory, rangeland condition and plant combination was determined by Range Value method and range trend was obtained by Trend Balance method. Time of bite-count record ...
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In order to determine the diet of Dalagh sheep, winter rangeland of Gomishan plain was selected. After delineating of the grazingland territory, rangeland condition and plant combination was determined by Range Value method and range trend was obtained by Trend Balance method. Time of bite-count record was done in morning and afternoon in a five-day period; first week of November (1389) and last week of April (1390). The diet selection of sheep was evaluated by direct vision method and comparison of the diet in two record periods was done by T-test and one way ANOVA method. Result showed that the most selection of sheep was Aeluropus littoralis (36/6% in a.m. & 33/3% in p.m.) and the minimum also was Halocnemum strobilaceum (1/01% in a.m. & 0/23% in p.m.) in first record. Lastly, the most selection of sheep was Hordeum marinum (42/99% in a.m. & 59/76% in p.m.) and the minimum also was Salicornia herbaceae (2/04% in a.m. & 4/16% in p.m.) Moreover, there is not any significant difference between grazing periods. Although shrub is the most species in the study area, diet selection of sheep was grasses form. It was for their growing phenology period that this time, grasses are palatable than halophytes shrubs.
Mohammadali Keyani; Bahador Zarei
Abstract
Good governance, by providing space for participatory processes, is a good platform for strengthening civil society alongside government and the private sector in governing countries. Meanwhile, NGOs, as an important part of civil society, are trying to fill government loopholes in geographical areas. ...
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Good governance, by providing space for participatory processes, is a good platform for strengthening civil society alongside government and the private sector in governing countries. Meanwhile, NGOs, as an important part of civil society, are trying to fill government loopholes in geographical areas. In the discussion of non-governmental organizations, we can point to their importance as one of the key players for achieving good governance in the context of promoting social capital. The present study, which is a descriptive-comparative study, compares the components of good governance (with those of accountability, transparency, accountability and rule of law) by non-governmental organizations and local governments in Iran. The sample size of the study was 296 people (157 members of NGOs and 140 members of local government) who were selected through available sampling and snowball. The results showed that the NGOs have performed better than the local government in achieving the components of good governance. The components of good governance were significantly related to the control indicators of poverty, corruption, and the elimination of discrimination and inequality, which is a great goal to be achieved through the active performance of non-governmental organizations.
Fatemeh Salari; Mehdi Ghorbani; Arash Malekian
Abstract
Water resources local governance can is one of the most influential collaborative approach in the water resources management. Social monitoring of local stakeholders plays an important role in planning, resources management and water efficient governance. Therefore to achieve this goal, social network ...
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Water resources local governance can is one of the most influential collaborative approach in the water resources management. Social monitoring of local stakeholders plays an important role in planning, resources management and water efficient governance. Therefore to achieve this goal, social network analysis has been considered as an approach of analysis of the relationship among local stakeholders, in order to sustainable management of water resources. This study aims to social monitoring in local stakeholders network using social network analysis in Razin watershed located in Kermanshah province. This work based on social network analysis approach as method with emphasis on trust and collaboration ties and quantitative and mathematical indicators on the macro-level of local stakeholders network (Density, Centralization, Reciprocity and Geodesic Distances). The results showed that the level of social capital in the village has been measured weak. The degree of reciprocity indicator for trust and collaboration ties and the stability of network is weak. Also the level of correlation between trust and collaboration is 37 percent. The results of the mean geodesic distance on the basis of trust and collaboration ties showed that circulation velocity of trust and collaboration is moderate to low. Can be concluded on the basis of the results, weak social capital and low union between stakeholders, makes reduce circulation of trust and collaboration and therefore local governance of water resources in the region is challenged
Reza Bagheri; Mehdi Ghorbani; Shahram Khalighi Sigaroudi; Amir Alambeigi
Abstract
Water deficit caused by climate change due to the extent and magnitude of the social and economic damages it causes, is one of the most dangerous natural disasters that causes irreparable damage to the agricultural and water resources of the country. In other words, it has devastating effects on the ...
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Water deficit caused by climate change due to the extent and magnitude of the social and economic damages it causes, is one of the most dangerous natural disasters that causes irreparable damage to the agricultural and water resources of the country. In other words, it has devastating effects on the productive, economic, social and environmental sectors. The purpose of this study was to analyze the components of resilience and present a model of resilience of the local community in the face of climate change. The statistical population of the study consisted of rural community of Nodushan watershed which was used for sample size of Cochran formula and 100 people were surveyed based on a researcher-made questionnaire. The Resilience Component Analysis Questionnaire was used. Data were analyzed using SPSS25 and LISREL8.8 software. To investigate the fit of the resilience component measurement model, the data was analyzed used LISREL software. The results showed that among the resiliency indices, the indicators of "local networks" and "financial and infrastructure" with 91 percent and 84 percent path coefficients were better than other indices, respectively. "Compatible management status" and "risk-taking" with 10 percent and 8 percent path coefficients, respectively, are not appropriate. Also, results showed that the goodness-of-fit indices had values and confirmed the resilience dimension measurement model with the data. Therefore, it can be acknowledged that the results of this study can in actions and can be effective in promoting and adopting climate change crisis mitigation mechanisms to create resilience in the local community.
somaie dehdary; zohreh kuhansani; fatemeh shojaee; ruhangiz kazemi
Abstract
To evaluate the effect of zeolite on the growth of plants in drought conditions. Cymbopogonolivieri, Medicago sativa, Medicagoscutellata in three zeolite levels (2 g, 4 g and zero in a kilogram potting soil) with 15 repetitions was considered. After ensuring the germination of plants, 7-day irrigation ...
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To evaluate the effect of zeolite on the growth of plants in drought conditions. Cymbopogonolivieri, Medicago sativa, Medicagoscutellata in three zeolite levels (2 g, 4 g and zero in a kilogram potting soil) with 15 repetitions was considered. After ensuring the germination of plants, 7-day irrigation tension was applied to them. It was found out that following the first tension, the effect of zeolite in improving viability and mitigation of drought tension will appear and it is observed that in 20% and 40% Zeolite treatments, the percentage of viability and germination of plants is much more in comparison with control group. Gradually, following applying tensions, the average number of remaining saplings decreased in control treatments. The highest percentage of residual base, the whole plant length, stem fresh weight, and dry weight of zeolite was observed in Cymbopogonolivieri in the treatment of 40%. More traits such as stem length, fresh weight, dry weight and fresh weight roots in the treatment of 40% zeolite in Medicagoscutellata species improved. The highest root weight was observed in Medicago sativa using 40% zeolite. No significant difference was detected in terms of wet root length in three plant species.
bahram amiri; nahid takin; hosien gharah daghi; behrouz rasouli
Abstract
In this study, a new and valuable forage source was introduced with combination and silage of alfa-alfa, Halocnemum and Mesquite via chemical, gas production and in vivo methods. To perform this research, first the right amounts of the species were collected. Then they were cut by chopper to the dimensions ...
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In this study, a new and valuable forage source was introduced with combination and silage of alfa-alfa, Halocnemum and Mesquite via chemical, gas production and in vivo methods. To perform this research, first the right amounts of the species were collected. Then they were cut by chopper to the dimensions of less than 5 cm. Then, Halocnemum, mesquite fruit, alfalfa and molasses were silaged according to dry matter weight in 4 treatments with three replications in a RCBD. These treatments include: 50H-10K-30U-10M, 50H-20K-20U-10M, 50H-30K-10U-10M, 30H-30K-30U-10M. At the end of experiment (28 d) the amounts of silage qualitative factors were measured using standard methods suggested by AOAC. 3 Ghashghaee yearlong sheep (45+2.5 kg) and 3 Toodeh siah yearlong goats(30 +2.5 kg) used in a split-plot scheme with 3 replications for estimation of silage consumption. According to the results, 50H-20K-20U-10M and 50H-10K-30U-10M treatmentshave the most digestibility at 12 hours of incubation. Study of silage nutritional value by gas production methods indicated that 50H-20K-20U-10M treatment has the greatest amount of DOM, OMD. DMD and ME were consumed more by the livestock. Therefore, we can recommend it as an appropriate combination with economic and feeding benefits.
D Talebpoor Asl; S Khezry
Volume 63, Issue 3 , December 2010, , Pages 341-358
Abstract
The Mahabad River Watershed has been exposed to severe erosion as a result of landuse change. The aim of this study is to quantify the amount of sediment yield and the relationship between land use change and slope. Different sources such as geologic and topographic maps, satellite images, hydrometric ...
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The Mahabad River Watershed has been exposed to severe erosion as a result of landuse change. The aim of this study is to quantify the amount of sediment yield and the relationship between land use change and slope. Different sources such as geologic and topographic maps, satellite images, hydrometric as well as meteorological data were used to extract and gather the information needed for this research. Six factors including altitude, slope, precipitation, rock erodibility, time of concentration and land use were specified as the most effective factors. The overlapping of the six factors maps resulted in the preparation of sediment delivery potential map. The distribution maps prepared on each of these parameters and their overlaps have shown that areas with more severe slopes are categorized as highly susceptible to erosion. However, in areas with resistant rocks, change of land use has been the determining factor. Comparison of water and sediment discharge data of 1996-97 with 2001-02(similar annual water volume) showed that the sediment yield has increased. Studying land use map prepared using satellite imagery of 1987 and 1998 showed that land use of the area has severely changed from pasture to dryland farming. This factor has also caused the intensification of mass movement recently occurred in the area. Landuse is the only parameter modified by human, and it is the only one which can be quickly and effectively changed. Hence, it seems that the upstream areas in the south and southwest of the basin with low concentration time, steep slope, high erodibility, high amount of precipitation, and the landuse of forest and pasture mixture as well as alluvial terraces with fine and granular sediments are the most sensitive areas which need protecting and control measures.
Maryam Khosravi; Ali Salajegheh; Mohammad Mahdavi; Mohsen Mohseni Saravi
Abstract
It is necessary to use empirical models for estimating of instantaneous peak discharge because of deficit of gauging stations in the country. Hence, at present study, two models including Artificial Neural Networks and nonlinear multivariate regression were used to predict peak discharge in Taleghan ...
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It is necessary to use empirical models for estimating of instantaneous peak discharge because of deficit of gauging stations in the country. Hence, at present study, two models including Artificial Neural Networks and nonlinear multivariate regression were used to predict peak discharge in Taleghan watershed. Maximum daily mean discharge and corresponding daily rainfall, one day antecedent and five days antecedent rainfall, sum of five days antecedent rainfall and monthly mean temperature were extracted in Gatehdeh, Mehran, Alizan, Joestan and Gelinak hydrological units and entered into neural network model (from upstream to downstream, respectively). The feed forward network was used with one hidden layer and back-propagation algorithm. Then, the models were trained, validated and tested in three stages. The observed and estimated peak discharges of the models were compared based on RMSE and r. The results showed that neural network has better performance than nonlinear multivariate regression.
Morteza Khodagholi; Razieh Saboohi
Abstract
The genus of Astragalus accounts for 31.4 percent of area of Isfahan Province with Astragalus verus Olivier as a foremost species. This study aimed to investigate the contributing climatic variables to distribution of this species. Moreover, the trends of climatic variables and their influence on the ...
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The genus of Astragalus accounts for 31.4 percent of area of Isfahan Province with Astragalus verus Olivier as a foremost species. This study aimed to investigate the contributing climatic variables to distribution of this species. Moreover, the trends of climatic variables and their influence on the species mortality. In doing so, 56 climatic variables relating to January, March, July, and the entire year were utilized. The Principal Component Analysis was employed to trim down the number of variables and their trends were analyzed using the Mann-Kendall test. The correlation analysis was ultimately used to investigate the association between climatic changes and mortality of Astragalus verus. Results showed that cooling temperature contributed most in the distribution of the species. The trend of temperature also indicated that mean temperature followed an upwards trend in most months of the year. Except Ardestan, Isfahan, Eastern Isfahan, and Kaboutar-Abad, annual precipitation declined but not significantly at the level of 1 and 5 percent. The dried up stands observed in Naeen region was estimated to be around 25 percent where the largest decreasing precipitation and increasing temperature was recorded. This estimate was only around 8 percent in Khansar and Chadegan whose increasing temperature and wind speed as well as decreasing precipitation were compensated by having a good growing potential.
mina bayat; Hossein Arzani; adel jalili; hassan ghalij nia
Abstract
In this study the effects of three important factors: the climatic precipitation, temperature and relative humidity on the amount of canopy cover and forage production in a period of five years (1381-1385) and 1392 in semi-steppe rangelands Reineh and Polur in the Mazandaran province studied. The statistical ...
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In this study the effects of three important factors: the climatic precipitation, temperature and relative humidity on the amount of canopy cover and forage production in a period of five years (1381-1385) and 1392 in semi-steppe rangelands Reineh and Polur in the Mazandaran province studied. The statistical models (simple and multiple regression) to find the relationship between various forms of vegetative cover and annual forage plants using climate variables in different periods of time with Minitab.14 and Excel software was used for data analysis. The results of six years of study in a semi-steppe rangelands Polur and Reineh showed an average canopy cover of 51 percent and the average yield was 372 kg per hectare. The total vegetation cover of Rineh pastures had the most relation with a total rainfall of the growth season and the March and the average temperature. The temperature was more effectively than rainfall in annual yield. And The yield affected by July temperature. The total vegetation cover of polur had not significant relation with climate factors but each of the vegetation form in Different time base had significant relation. The total grazing species yield of plour affected by growth season rainfall. So instead of one year measurement of vegetation cover and production can be estimated the production and vegetation cover fluctuation according to climate parameters. With long-term vegetation cover and production data, can be determined the available forage and pasture capacity to prevent the range degradation.
Mohammad Ali Zare Chahouki; Lyla Khalsi Ahvazi; Hossein Azarnivand; Asghar Zare Chahouki
Abstract
The aim of this study preparation of the predicted soil maps by using kriging and Inverse Distance Weighting methods in east rangeland of Semnan. Sampling was done within each unit of sampling parallel transects and 1 vertical transect with 750m length. Soil samples were taken from 0-20 cm in starting ...
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The aim of this study preparation of the predicted soil maps by using kriging and Inverse Distance Weighting methods in east rangeland of Semnan. Sampling was done within each unit of sampling parallel transects and 1 vertical transect with 750m length. Soil samples were taken from 0-20 cm in starting and ending points of each transect. There were used kriging and Inverse Distance Weighting methods by Gs+ and GIS software to predict clay, sand, lime, EC and available moisture factors. For comparing these methods, cross validation were used by statistical parameters of MAE and MBE. Results showed that kriging method is better than Inverse Distance Weighting method in all factors except clay factor.
