Fereshteh Babaei; Ataollah Ebrahimi; Ali Asghar Naghipour; Maryam Haidarian
Abstract
Climate change is one of the main determinants of plant species redistribution and biodiversity loss. This study aims to predict the impacts of climate change on the geographic distribution of Agropyron intermedium in Chaharmahal-va-Bakhtiari province as a part of Central Zagros, Iran. The presence points ...
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Climate change is one of the main determinants of plant species redistribution and biodiversity loss. This study aims to predict the impacts of climate change on the geographic distribution of Agropyron intermedium in Chaharmahal-va-Bakhtiari province as a part of Central Zagros, Iran. The presence points of studied species were recorded from our field surveys in the studied area. In this study, we used the ensemble predictions based on five species distribution models. The future projections were made for the year 2070 with three scenarios SSP126, SSP370, and SSP585, and two general circulation models GFDL-ESM4 and MRI-ESM2-0. According to the results, Random forest model and the generalized boosted model were recognized as the most reliable models for predicting species distribution. The most effective variables in the suitability of the A. intermedium species habitat were, respectively, elevation, Precipitation of wettest month, and slope. According to the finding, about 21.26% of the study area for A. intermedium species have had suitable habitats. The decline of suitable habitats of A. intermedium will be 36.06% to 63.20% under the GFDL-ESM4 general circulation model and 36.69% to 65.17% under MRI- ESM2 general circulation model due to climate change. The results also indicated that climate change will alter the range size of studied species and will probably shift to higher elevations in the future. The results of this study can be used to protect the habitat of the range plant species, as well as its rehabilitation and restoration.
Kourosh Shirani; Reza Naderi Samani
Abstract
The aim of this study is to prioritize effective factors, landslide susceptibility zonation assessment using maximum entropy (MaxEnt) and dempster shafer models in Doab Samsami watershed of Chaharmahal and Bakhtiari province. For this purpose, 15 factor maps affecting landslide occurrence as independent ...
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The aim of this study is to prioritize effective factors, landslide susceptibility zonation assessment using maximum entropy (MaxEnt) and dempster shafer models in Doab Samsami watershed of Chaharmahal and Bakhtiari province. For this purpose, 15 factor maps affecting landslide occurrence as independent variables and landslide distribution map as a dependent variable were prepared and weighted using frequency ratio index (FR) and landslide distribution map in the environment ArcGIS® 10.8 . In order to implementation and validation of models, landslide distribution data were randomly divided into two categories of training and test data in the proportion of 70 and 30%, respectively. Maximum Entropy (MAXENT) and Dempster Shaffer models are performed and landslide susceptibility zonation maps are prepared and each model is divided into five very low to very high. In order to evaluate the classification accuracy and validation of the models, the frequency ratio and seed cell area index (FR&SCAI) and the area under receiver characteristic curve (AUC-ROC) were used, respectively. According to the results of the maximum entropy model, annual precipitation factors, lithology, distance to road and drainage land use are important in landslide occurrence, respectively. According to landslide susceptibility zonation maps in both models, more than 50% of landslides occurred in high and very high susceptibility categories. Finally, the validation results of the models showed that the Demester shafer model with AUC-ROC index of 0.95 and classification accuracy with higher FR & SCAI index, greater efficiency and desirability for zoning, modeling and landslide prediction in the study area.
vahid karimian; Mohsen Farzin
Abstract
In this research, the nutrient value of Zygophyllum eurypterum, Salsola orientalis, and Sanguisorba minor during different growing periods in the winter rangelands of Gachsaran County was considered. For this purpose, sampling was done randomly and with 4 repetitions from the species in different periods ...
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In this research, the nutrient value of Zygophyllum eurypterum, Salsola orientalis, and Sanguisorba minor during different growing periods in the winter rangelands of Gachsaran County was considered. For this purpose, sampling was done randomly and with 4 repetitions from the species in different periods of growth. To determine the quality, crude protein percentage (CP), acid detergent insoluble fiber (ADF), dry matter digestibility (DMD) and metabolizable energy (ME) were evaluated. The results showed that the quality indices in the studied species have significant differences (p<0.05). The highest values of crude protein percentage, dry matter digestibility percentage and metabolic energy (MJ/kg) are 16.91, 60.88 and 8.35, respectively, was observed in S. minor and the lowest values of the indices 7.39, 49.05 and 6.33, respectively, were detected in S. orientalis. Also, the highest amount of ADF was obtained in S. orientalis (45.66%) and the lowest in S. minor (36.16%). The nutrient value of the plants in different growth periods has significant differences (p<0.05). In the growth period, the highest percentage of crude protein (20.87) belongs to the Z. eurypterum, the highest percentage of digestibility (65.92) and the amount of metabolic energy (9.2 Mj/kg) was belonged to the S. minor and the lowest percentage of crude protein (8.65), dry matter digestibility percentage (57.34), and metabolic energy (7.74 Mj/kg) was belonged to the S. orientalis. The highest (36.25%) and the lowest percentage of ADF (31.50%) at this stage belong to S. orientalis and S. minor. In the flowering period, the highest amount of crude protein percentage (17.50), dry matter digestibility percentage (62.50) and metabolic energy (8.62) belong to the S. minor.
Sadegh Dalfardi; Ali Salajegheh; Alireza Moghaddam Nia; Mohammad Danesh Yazdi; Hossein Hashemi
Abstract
Accurate slope map and the governing river network of a river basin are key inputs of hydrologic models. The purpose of this study was to investigate the effectiveness of the PriorityFlow tool in topographic data processing with the aim of improving slope map extraction in the eastern Faryab Basin. PriorityFlow ...
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Accurate slope map and the governing river network of a river basin are key inputs of hydrologic models. The purpose of this study was to investigate the effectiveness of the PriorityFlow tool in topographic data processing with the aim of improving slope map extraction in the eastern Faryab Basin. PriorityFlow is a tool in the R programming environment, which aims to generate the correct slope map and to form a network of continuous pathways that matches the observed river network. To process the digital elevation model and prepare the slope map, three input files were used, including the digital elevation model, the representative map of the watershed and the representative map of the observed river network of the study area. After producing the slope map using this package, the obtained results were compared with the outputs obtained from other traditional tools available in the Parflow hydrological model. Specifically, the river network map related to the two slope maps were extracted by the Parflow model under the condition of very low permeability of the domain surface and compared with the observed river network of the study basin. The results showed that the slope map produced by the PriorityFlow tool has led to the production of a more accurate river network that matches the real river network of the eastern Faryab basin. Also, this software package is able to produce the slope map with enhanced accuracy and based on non-diagonal connections along the cell levels in the digital elevation model of the study area.
Amir Fallahpour; Rasoul Khosravi; Masoud Masoudi; Hassan Moghim
Abstract
Introduction: In the comprehensive and integrated watershed management approach, watershed management has progressed from a mechanical and biological program to a comprehensive and integrated management system, through which we can guarantee human needs for the present and future generations in a reasonable ...
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Introduction: In the comprehensive and integrated watershed management approach, watershed management has progressed from a mechanical and biological program to a comprehensive and integrated management system, through which we can guarantee human needs for the present and future generations in a reasonable way. Despite the fact that there is no doubt about the effectiveness of most watershed projects, the alignment of these projects with the goals of sustainable development needs to be evaluated. Material and Methods: We used IUCN method to assess sustainability of the watershed management plans in Sistan and Tol Heidari watershed of Jahrom County from 2005 to 2021. The most important strength of this method is simultaneous consideration of human and ecosystem factors. For this purpose, using opinion of experts, we determined criteria and indices in two main categories including ecosystem and human welfare. Finally, we selected three criteria and 15 indices for ecosystem section and four criteria and 13 indices for human section to assess watershed sustainability condition. The sustainability assessment of the watershed was performed with and without weighting the indicators and criteria. Results: The final score, according to the stability barometer respectively in the first method, was 66.30 before implementation and 71.33 after implementation. In the second method, the final score of 60.64 and 66.66 which indicates an upward trend in the level of stability and increase in the state of stability. Discussion: The results of the present study show that the watershed projects carried out in the region have been able to bring about a relative improvement in the ecological and economic-social conditions of the region.
Ahmad Azizi; Mohsen Maleki; Masoome sadat Hosseininasab
Abstract
Because ofthe conflicts of interest, the interaction of beneficiaries and natural resource experts inIran hasbeen challenged.This area was studied asthetarget, due totheechologic andsocial condition andconsideringthe existing conflicts. In this study, legal, managerial, exploitation, and social components ...
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Because ofthe conflicts of interest, the interaction of beneficiaries and natural resource experts inIran hasbeen challenged.This area was studied asthetarget, due totheechologic andsocial condition andconsideringthe existing conflicts. In this study, legal, managerial, exploitation, and social components were examined from the perspectives of both experts and beneficiaries. 188 questionnaires were completed with the Snowball Method. The validity of the main variables of questionnaire was greater than 0.7. The Mann-Whitney U-test was used to compare differences between two groups. The results show that in addition to the natural resources conflict in the whole region, in terms of perspective, there is a significant difference between the factors affecting the conflict between the local community and government experts. The most important components for increasing the conflict in this region from the perspective ofstakeholders are the lack oflaws, the presence of non-natives inrangelands and forests, the low presence of women in this natural resources field and according to the experts, lack of land-use conversion, and level of awareness of stakeholders. Land grabbing, Coaling and understory tillage are the most challenging issues in the west of Gilan province.From the managerial point of view, both groups have declared that the most effective way to reduce the conflict is the confinement of forests and pastures, but the participatory management issues was not accepted according to the two groups’ viewpoints. Effective presence of experts in the field, recognizing the livelihood potentials of the region, and encouraging and educating people to know alternative jobs are suitable ways to reduce conflict.
Farhad Hasani Dorabad; Naser Mashhadi; AmirReza Keshtkar
Abstract
The desert environment is aeolian, being dominated by the wind. The dynamics of wind erosion are driven by both natural processes, including climate and its fluctuations, and human activity. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving ...
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The desert environment is aeolian, being dominated by the wind. The dynamics of wind erosion are driven by both natural processes, including climate and its fluctuations, and human activity. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. The aim of current research is to evaluate the spatio-temporal dynamics of the aeolian process based on the sand dunes morphology and the analysis of the spatial correlation between wind erosion dynamics and climate fluctuations. Based on meteorological, remote sensing and field observations data, the impacts of climate fluctuations on the temporal and spatial changes of the aeolian process were evaluated according to the indicator of the creation and expansion of sand dunes .MODIS remote sensing data was used to study the sand dunes morphology. The temperature, precipitation, wind speed and other meteorological data used in this study were all derived from two synoptic stations of Qom and Kashan. The analysis of the elongation and form of the sand dunes as the wind direction indicator showed that the studied area is affected by the winds region of the Qom (northwest and west). The results of climate studies showed that over the last 27 years, the region has a rising temperature trend, while the average precipitation in the region has decreased in the same period. The relationship between drought conditions and aeolian process showed that the region experienced severe drought conditions more than normal or abnormally dry conditions during 1369 to 1395.
Negar Tayebzadeh Moghadam; Bahram Malekmohammadi
Abstract
The response of water balance components as indicators of hydrological performance to stimuli such as land use change is of strategic importance. In this study, the effect of land use change on water balance components was evaluated, focusing on the relationships and change of the main indicators of ...
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The response of water balance components as indicators of hydrological performance to stimuli such as land use change is of strategic importance. In this study, the effect of land use change on water balance components was evaluated, focusing on the relationships and change of the main indicators of water yield and sediment yield. Based on this, the Markov chain model was used to predict land use in 2040. Also, the American soil and water assessment tool was developed as a base model for evaluating and estimating hydrological indicators in the Taleghan Watershed as a mountainous watershed with structural heterogeneity. The results of model showed that the increase of settlements and urban development in Taleghan watershed will result in increased runoff, increased water yield and sediment yield indicators, and more sedimentation. Land use change leads to an increase of sediment yield by 11 times until 2040. The conversion of pastures to barren lands is the most important land use change that can increase sediment yield. Also, the increase of barren lands will be the reason for the reduction of evapotranspiration in some sub-basins of this watershed. Increasing rainfall and decreasing soil permeability will increase surface runoff, and as a result, soil erosion and sediment yield will increase. In this study, exactly the sub-basins that had the highest quantitative amount of predicted water yield index also had the highest quantitative amount of sediment yield index and increased sedimentation. In this research, it was determined that land use change as a type of structural change in the land will have visible effects on the functions and hydrological responses of the watershed.
Ahmad Godarzi; Soheilasadat Hashemi; Behnaz Attaeian
Abstract
The purpose of this research was investigation of soil physicochemical and particle distribution in three agricultures, rangeland and forest park land use in two surface (0-15 cm) and subsurface (15-30 cm) depths in Oshtorninan city on the Lorestan province. Soil sampling was done in 45 points in three ...
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The purpose of this research was investigation of soil physicochemical and particle distribution in three agricultures, rangeland and forest park land use in two surface (0-15 cm) and subsurface (15-30 cm) depths in Oshtorninan city on the Lorestan province. Soil sampling was done in 45 points in three land use. Some soil physico-chemical properties were determined in laboratory. This experiment was arranged in a factorial manner. The results showed that the change of rangeland use to agriculture has resulted in a decrease in clay content, cation exchange capacity, soil carbon, nitrogen and soil particle size. Changing the land use of pasture to forest park has led to an increase in the amount of clay, silt and soil acidity. Mean comparison showed that there was no significant difference between bulk density and electrical conductivity in the three land uses (p ≤ 0.01). Analysis of the data showed that the soil cation exchange capacity, organic carbon, clay and silt content in three land uses and two depths were significantly different (p ≤ 0.01). Land use factor also showed a significant different on soil sand and lime percentage (p ≤ 0.01). The soil granulation did not change with the conversion of the rangeland in to a forest. Increased organic carbon and soil clay content could be the reason for this. In general, land use change from pasture to agriculture similar to other research is unfavorable, but land use change to forest park has improved clay content, cation exchange capacity and soil organic carbon.
Ahmad Gillvare; Gholamreza Zehtabian; Hassan Khosravi; Hossein Azarnivand; Salman Zare
Abstract
Due to the importance of vegetation cover in these areas, the aim of this study was to investigate the effect of drought, on vegetation of HablehRood watershed.Initially, NDVI index obtained from MODIS sensor was used to study vegetation cover and then SPI index based on rainfall data of two basins in ...
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Due to the importance of vegetation cover in these areas, the aim of this study was to investigate the effect of drought, on vegetation of HablehRood watershed.Initially, NDVI index obtained from MODIS sensor was used to study vegetation cover and then SPI index based on rainfall data of two basins in two arid and semi-humid climates was used for drought assessment (2001-2018) using image processing methods. The results showed that during this 18-year period, 53% of the region had droughts on average. Also during the period 2001-2003, drought was more severe than other periods (2003-2018). In addition, the highest vegetation index occurred in 2005, indicating that vegetation was affected by rainfall fluctuations in the region. The correlation matrix between the three indices indicated that NDVI had the same correlation with SPI and annual rainfall. The results of this correlation in dry and semi-humid climates showed that the correlation was 0.38 and 0.25, respectively. These results indicate that this relationship is positive and robust in different climates of a region؟. On the other hand, drought class is mainly located in dry and semi-humid climates, with 55.55% and 50% in relatively normal drought class, respectively. Based on the above, it can be concluded that using remote sensing data can monitor the response of semi-humid and dry arid ecosystems to climate change. The study also showed that arid and semi-arid regions are highly susceptible to climate change and human anomalies. Therefore, the destruction of these lands will have many environmental and economic consequences.
Zahra Noori; Arash Malekian
Abstract
Groundwater is important water resource supply, especially in arid and semi- arid regions. Increased utilization of the ground water aquifer leads to significant reduction in the storage of reservoirs. This study evaluates the hydrogeological drought in Garmsar plain using Groundwater Resource Index ...
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Groundwater is important water resource supply, especially in arid and semi- arid regions. Increased utilization of the ground water aquifer leads to significant reduction in the storage of reservoirs. This study evaluates the hydrogeological drought in Garmsar plain using Groundwater Resource Index (GRI). First, we used 17 piezometric wells data over 2001-2011 statistical period to calculate GRI in the beginning, middle and end of the period. So, we used different interpolation method including geostatiscal method ordinary kriging (OK), simple kriging (SK) and deterministic methods including inverse distance weighting (IDW) to prepare the maps over three periods. The mean absolute error (MAE) and root mean square error (RMSE) indices were used to evaluate the accuracy of simple kriging, ordinary kriging and IDW classification based on the drought maps. The results showed that the values of MAE and RMSE criteria for simple Kriging is better than the other methods and indicates the suitability of this method for zoning GRI. According to the results, the most severe hydrogeological drought in Garmsar plain was at the end of 2011, that 91.16 % of the study area was suffered from severe drought. SPI was used for considering the effects of meteorological drought in the time scale of 3, 6, 9, 12, 24 and 48 months on groundwater. The correlation between SPI and GRI showed long-term timescale of 48 monthly has the greatest correlation with groundwater level.
Maryam NAEIMI; Parvane Ashouri; Farhad Khaksarian; Samira Zandifar; Masoud Mohammad aliha
Abstract
Degradation of the Earth's biodiversity has resulted in damage that in many cases is irreparable to humans. The purpose of the present study is to determine the boundaries and environment of the proprietary and medicinal species of Kozal Damavandi (Diplotaenia damavandica Mozaffarian, Hedge & Lamond). ...
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Degradation of the Earth's biodiversity has resulted in damage that in many cases is irreparable to humans. The purpose of the present study is to determine the boundaries and environment of the proprietary and medicinal species of Kozal Damavandi (Diplotaenia damavandica Mozaffarian, Hedge & Lamond). This plant has received a lot of attention due to the presence of special effective compounds that have therapeutic effects on most skin complications. For this purpose, a habitat map was first prepared with local visits and previous reports. Then, its environment including physiography, accompanying species, lithology, soil and water resources characteristics were studied. The results showed that this plant species grows at the altitude of 2400 to 3600 meters above sea level, with a slope of above 60% and an altitude of above 35ᵒ 40’. Lithological study of the habitat area in dense areas shows the thick green tuffs, Jeirood foundation, shale, and dark sandstone. Also, in terms of soil science, there were significant differences between the examined parameters of K, P, and SO4, while regarding the water resources the significant parameters are Cl and NO3. Investigating the deterioration of vegetation also showed that the highest coverage density in the region was in 2014. The results of the present study will be used to determine the limiting factors of the habitat and to investigate the possibility of the growth of this exclusive species.
Naser Mashahadi
Abstract
The dynamics of human activities threaten the sustainability of global life-support systems. Analyze of anthropogenic transformation data play a central role in environmental problems evaluation. This study aims to analyze human activities in watershed. Studies and analyzes revealed that the anthropogenic ...
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The dynamics of human activities threaten the sustainability of global life-support systems. Analyze of anthropogenic transformation data play a central role in environmental problems evaluation. This study aims to analyze human activities in watershed. Studies and analyzes revealed that the anthropogenic transformation variables include the type, intensity and trend. Spatial and temporal patterns of the type of activity (land use), intensity and human intervention were studied using satellite images and field observation. The classification and land use map were done in two phases: The functional phase included the main land uses including agriculture, rangeland, urban and water resources, and the activity phase included ten types of land use. The study of the human interventions intensity in land use units was carried out based on the temporal extension of agricultural land development (agricultural land use), the rangeland condition assessment (rangeland land use) and the area extent of under influence (urban area and water resources). The results of land use studies identified that Rangeland lands cover 77.2 percent and agriculture, urban area and water resources land uses accounted for 21.5, 1.1 and 0.2 percent, respectively. The results of the intervention trend indicated that the trend continues from normal conditions to the replacement by technogenous structures. This trend has revealed growth of agricultural activity in rangeland and as well as the tremendous loss in cropland in uneven urban and industrial growth. The results of the study show the compatibility between the three variables of anthropogenic transformation; ie, the type, intensity and trend.
Roghaye Shad; Mehdi Ghorbani; Khaled Ahmadaali; Aliakbar Nazari Samani; Maryam Yazdanparast
Abstract
Land use changes in countries like Iran, which is facing space limitations, should be thoughtful and in accordance with proper planning, just like water consumption. On the other hand, the inherent dynamism of human beings and their needs has made the way and extent of land use change over time. Therefore, ...
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Land use changes in countries like Iran, which is facing space limitations, should be thoughtful and in accordance with proper planning, just like water consumption. On the other hand, the inherent dynamism of human beings and their needs has made the way and extent of land use change over time. Therefore, the aim of this research is the dynamic modeling of land use changes based on the human-environmental system in Taleghan watershed. For this purpose, land use maps for the years 1994, 1999, 2002, 2009, 2014, 2019 were classified into six classes of pasture, forest, agricultural land, barren land, residential land, and water using Landsat satellite time series images. After the validation of the maps and the detection of changes, under the three scenarios of current economic growth, rapid economic growth and sustainable development, simulation was carried out until 1435 using dynamic system modeling. The results of detecting land use changes during the period show that the trend of changes in agricultural lands, pastures, forests, has been decreasing, and barren lands and residential areas have always had an increasing trend during the survey period. The results of the simulation show that among the three scenarios examined, the sustainable development scenario of coordination between the amount of land utilization and meeting the needs of the community and economic growth has been acceptable. Therefore, it can be concluded that the sustainable development scenario is an important basis for land use planning in the coming years in order to reduce the destruction of natural resources and maintain a stable state in it, and this scenario will bring favorable economic growth in the future.
Shahbaz Mehrabi; Mohammad Reza Yazdani; Mehdi Ghorbani
Abstract
Prevention is the most appropriate way to deal with natural hazards. And resilience means maintaining the structure and function of the socio-ecological system in the face of unexpected events, one of the important branches of prevention. Chaharmahal va Bakhtiari province, due to its specific geographical ...
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Prevention is the most appropriate way to deal with natural hazards. And resilience means maintaining the structure and function of the socio-ecological system in the face of unexpected events, one of the important branches of prevention. Chaharmahal va Bakhtiari province, due to its specific geographical location, faces numerous environmental hazards annually. Therefore, in this study, the status of resilience in the face of environmental hazards in the governing system of this province was investigated. AHP method was used for this purpose. In the AHP process, based on the pairwise comparison of criteria and sub-criteria, the degree of association between both criteria and sub-criteria is compared and scores between 1-9 are assigned. The research data was analyzed based on Delphi method and hierarchical decision making process. The results showed that according to expert’s evaluation of resilience of socio-ecological systems of Chaharmahal va Bakhtiari province against climate change (4.51), drought (2.09) and soil erosion (2.02) were ranked first to third respectively. Because of this, climate change has attracted the attention of experts who have shifted the rainfall to snow ratio over the past two decades. So that from 70% snow and 30% rain, to 70% rain and 30% snow. However, much of the economic activity and livelihoods in the province depend on snow reserves.
Hossein Arzani; Esmaeil Alizadeh; Setareh bagheri; Mohammad Jafari
Abstract
Rangelands played an effective role in the country's economic and political development prior to its dependence on oil and its derivatives. Therefore, paying attention to the environmental and social stresses brought to these ecosystems highlights the need to use new technologies to diversify production ...
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Rangelands played an effective role in the country's economic and political development prior to its dependence on oil and its derivatives. Therefore, paying attention to the environmental and social stresses brought to these ecosystems highlights the need to use new technologies to diversify production sources and reduce costs. This study was conducted at the Taleghan range station with the aim of financially evaluating electric fences to encourage pastoralists to use this technology in rangelands. For this purpose, the income from the fencing project was investigated. The financial evaluation of the electric fencing project and the time period for its capital return in 2016 was done using the equations of net present value, benefit-cost ratio, internal rate of return, and net present value criterion at different discount rates. The total fixed and current costs of this project were equal to 330 million rials. The income from animal meat production, medicinal plants, the added value of electricity production, the income from the replacement of shepherds, and the net income were equal to 73%, 23%, 7.5%, 103%, and 120% respectively. The criterion of net present value at different discount rates was equal to 127%. Considering the economic nature of fencing technology and the existence of economic benefits resulting from it in the form of a wide spectrum of ecosystem services for the beneficiaries of rangelands, the importance of promoting the use of new technologies in rangelands to maintain and support the production chain of rangelands is highlighted.
Ali Asghar Naghipour; Maedeh Sharifi; Ataollah Ebrahimi; Elham Ghesareh Ardestani; Sina Nabizadeh
Abstract
Fire is one of the important ecological factors that affect the dynamics of rangeland vegetation. In recent decades, the incidence of wildfires in semi-steppe rangelands has increased significantly, challenging the adaptive capacity of plants for post-fire regeneration. In the present study, the germination ...
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Fire is one of the important ecological factors that affect the dynamics of rangeland vegetation. In recent decades, the incidence of wildfires in semi-steppe rangelands has increased significantly, challenging the adaptive capacity of plants for post-fire regeneration. In the present study, the germination response of eight annual and perennial herbaceous species of semi-steppe rangelands of Chaharmahal va Bakhtiari province to fire products treatments including heat (60, 80 and 100° C), smoke, ash, and the combined effect of heat and smoke treatments were investigated. Also, percentage cover change of studied species, one year after the fire were measured in the field. The results showed that the germination of seeds of eight studied plant species showed a significant positive or negative reaction to at least one of the fire product treatments. Combined treatment of smoke and 60° C caused a significant increase in the mean germination percentage of Heteranthelium piliferum. This treatment also significantly reduced the mean germination time of Cousinia cylindracea. Ash treatment also increased the mean germination percentage of Alyssum linifolium and Stachys lavandulifolia. Vegetation sampling results also showed that among the eight species studied, H. piliferum and Taeniatherum crinitum were fire adapted and six species were tolerant. The results of this study can be used as a potential factor to understand the dynamics of vegetation and restoration of degraded rangelands.
Fatemeh Ebrahimi Meymand; Hasan Ramezanpour; Nafiseh Yaghmaeian; Kamran Eftekhari
Abstract
In recent years, the use of digital soil mapping (DSM) based on machine learning algorithms with the aim of preparing soil maps has become widespread with the basis of soil class prediction with the help of modeling the relationships between them and environmental variables. One of this method's challenges ...
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In recent years, the use of digital soil mapping (DSM) based on machine learning algorithms with the aim of preparing soil maps has become widespread with the basis of soil class prediction with the help of modeling the relationships between them and environmental variables. One of this method's challenges is the imbalanced nature of soil distribution in landscape, which leads to overfitting and underfitting of classes, and as a result, reduces the accuracy of many used models. This study was conducted to evaluate the ability of two machine learning algorithms, including random forests and support vector machines, for the digital mapping of soil classes with an imbalanced data set. This study was conducted on 95 soil profile classes at the family level, in 4000 hectares of land in the Honam sub-basin, Lorestan province. The issue of imbalance in soil classes was investigated by using six data sets, including the original soil data set and five data sets created by several resampling approaches including two manual classifications and three over-sampling, under-sampling, and Synthetic Minority Over-Sampling Techniques in the R software. The results showed that despite the low values of overall accuracy, the Geographical distribution of soils with high frequency in the study area in digital soil map obtained from the random forest and the original data set as well as Synthetic Minority Over-Sampling Technique, with conventional soil map of study area is significant. Therefore, the low observation number of other soil classes and as a result incorrect training of models can be considered as one of the main reasons for the low accuracy of the used models.
Meisam Alizadeh; Shafagh Rastgar; Jamshid Ghorbani
Abstract
The positive economic and social effectiveness of rangeland restoration projects activates the process of sustainable development and leads local communities to sustainable prosperity. The purpose of this study is to assess the socio-economic and environmental effectiveness of restored rangelands with ...
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The positive economic and social effectiveness of rangeland restoration projects activates the process of sustainable development and leads local communities to sustainable prosperity. The purpose of this study is to assess the socio-economic and environmental effectiveness of restored rangelands with Atriplex canescens plantation in Mallard county, Tehran province, Iran. The descriptive-analytical research method based on questionnaire was applied within the statistical population including 65 experts, 132 pastoralists and 29 local communities. The selection of samples was random and sample size were determined using Cochran's formula for three groups of experts (55), pastoralists (99) and local communities (27). To determine the validity of the questionnaire, a group of experts were used and Cronbach's alpha coefficient was used to estimate the reliability of the questionnaire. Also, Kruskal-Wallis test was used to compare opinions of the studied statistical societies. The results of the comparison of economic, social and environmental indicators showed that A. canescens plantation had a significant effect on social index and had no effect on the other two indicators. Social- environmental effectiveness of planting A.canescens is related to increasing livestock products and improving the condition of ranching, According to pastoralists, the greatest economic, social and environmental effectiveness from planting A.canescens has been related to increasing livestock products and improving the condition of ranching, increasing the level of public awareness. In general, results of effectiveness planting from the point of view of all three groups are close to each other and they often agree on the effectiveness of planting Atriplex. This alignment in thinking of plantation will lead to success in the implementation of projects and the achievement of goals and perspective,.
Leila Avazpour; Mehdi Ghorbani; Hossein Azarnivand; Hamed Rafiee
Abstract
Evaluate non-market functions and services of the environment, including tourism for many reasons, including the recognition and understanding of environmental and ecological benefits by humans, presenting the country's environmental issues to decision makers and planners, adjusting and modifying the ...
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Evaluate non-market functions and services of the environment, including tourism for many reasons, including the recognition and understanding of environmental and ecological benefits by humans, presenting the country's environmental issues to decision makers and planners, adjusting and modifying the set of national calculations such as GDP It is important to nationalize and prevent the indiscriminate destruction and exploitation of natural resources.The purpose of this study is to estimate the economic value of rangeland tourism function of 4 villages of Maneh and Samolghan counties of North Khorasan province, using conditional valuation method. the logit model was estimated using the maximum likelihood method. The required data were collected by completing 133 questionnaires and face-to-face interviews with visitors from all four areas. The sample size was obtained using Cochran's formula and the sampling method used is random sampling. Based on the results of the model used to determine the factors affecting the value of tourism in the region, the variables of marital status, employment status, proposed amount and rangeland attractiveness are significant at 5% probability level and effective factors in the WTP rate of visitors to use rangelands Are studied. the average WTP as input price for each visitor to use the rangelands of the region was 5880 Tomans and the recreational value of each hectare of rangelands in the region was 49556 Tomans per year. the rangelands of the studied villages have significant tourism value, which can help plannersand executives in planning, protection and sustainable use of rangelands in the region.
Nasrin Beiranvand; Alireza Sepahvand; Ali Haghizadeh
Abstract
In this study, five soft computing techniques, GP-PUK, GP-RBF, M5P, REEP Tree and RF were used to predict the SL in Cham Anjir, Bahram Joo, Kaka Reza and Sarab Syed Ali hydrometry stations in Khorramabad, Biranshahr and Alashtar sub-watersheds, Lorestan province. Total data set consists of rain, discharge ...
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In this study, five soft computing techniques, GP-PUK, GP-RBF, M5P, REEP Tree and RF were used to predict the SL in Cham Anjir, Bahram Joo, Kaka Reza and Sarab Syed Ali hydrometry stations in Khorramabad, Biranshahr and Alashtar sub-watersheds, Lorestan province. Total data set consists of rain, discharge and solute load (SL) of three sub-watersheds out of which 70% data used to training and 30% data were used to testing phase. Finally, the models’ accuracy was assessed using three performance evaluation parameters, which were Correlation Coefficient (C.C.), Root Mean Square Error (RMSE) and Maximum Absolute Error (MAE). Results suggest that GP-PUK and GP-RBF models works well than other modeling approaches in estimating the SL in low and high water-periods. The result showed that, In the high-water period, in Cham Anjir, Sarab Said Ali and Kaka Reza stations the GP-RBF model and in the Bahram Joo station the GP-PUK model with the highest C.C and the lowest error were selected the optimal models in estimating the SL. Also, in the low water period, result shown that in Cham Anjir, Sarab Said Ali and Bahram Joo stations the GP-RBF model and in the Kaka Reza station the GP-PUK model were the best models in estimating the SL. Therefore, these models can be used to estimate the solute load of nearby rivers by/without hydrometry station for the management of the quantity and quality of surface water.
ronak ahmadi; Qodratollah Heydari; gholamreza khoshfar
Abstract
The aim of this study was to identify factors influencing participation of landholders in the the rehabilitation and restoration of Choqakadoo rangeland in the city Sarpolzahab province of Kermanshah The aim of the research, applied research methodology, causal correlation. In addition to data processing ...
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The aim of this study was to identify factors influencing participation of landholders in the the rehabilitation and restoration of Choqakadoo rangeland in the city Sarpolzahab province of Kermanshah The aim of the research, applied research methodology, causal correlation. In addition to data processing descriptive statistics and correlation, multiple regression and path analysis method of inferential statistics were used. The results showed that the correlation coefficient attend public hearings, cordial relations with its neighbors, dominating the promoters on technical topics, providing extension services in the field of rehabilitation and restoration of rangeland, over responsibility for part of the program into landholders, membership in local organizations, familiar of landholders with and participate in training courses and promotional programs most of solidarity with the participation of landholders in the rangeland rehabilitation and restoration. Enter regression methods on variables including background indicate that their level of education, the most direct and positive effects (0/281) and the most positive effect and total (0/357) on the participation of landholders, also number of livestock, number of dependents and income are next in priorities. Among the variables including background age and years of exploitation has a negative effect (-0/482 , -0/468) on landholders' participation in the rangeland rehabilitation and restoration. So pay particular attention to these factors can be placed on the agenda of managers and planners and more participation of landholders in areas of rehabilitation and restoration of rangelands, provide in every area.
Seyed Majid Reza Hosseini Mofrad; Hassan Ahmadi; Ali Akbar Mehrabi; Baharak Motamedvaziri
Abstract
For this purpose, according to Cochran's equation, from Hashtgerd-Taleghan asphalt road 26 km long and Hashtgerd-Taleghan dirt road 9 km long, road sedimentation was calculated with 17 and 11 samples, respectively, and finally, using statistical relationships, the erosion rate was calculated. And sedimentation ...
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For this purpose, according to Cochran's equation, from Hashtgerd-Taleghan asphalt road 26 km long and Hashtgerd-Taleghan dirt road 9 km long, road sedimentation was calculated with 17 and 11 samples, respectively, and finally, using statistical relationships, the erosion rate was calculated. And sedimentation was estimated in the entire route. By direct measurement of erosion, the total sediments remaining along the route were equal to 17259.32 tons per year, of which 6241.45 tons per year are related to the excavation wall and 11017.87 tons per year are related to the embankment wall. Using the WARSEM model, the total amount of sedimentation from asphalt and dirt roads was estimated as 15172.67 tons per year, equivalent to 52.14 tons per hectare per year, of which 9464.53 tons per year, equivalent to 48.03 tons. Per hectare per year, the contribution of the excavation wall and the embankment wall of the asphalt road is 14.5708 tons per year, which is equivalent to 22.63 tons per hectare per year, the contribution of the excavation wall and the embankment wall of the dirt road. The sensitivity of the WARSEM model for the standardized parameters for the asphalt road showed that the slope and geological factors are important factors in the sedimentation of the embankment wall and the height factor of the embankment wall is a very important parameter in the sedimentation of the embankment wall. The sensitivity of the model on the dirt road according to this score of the parameters was very close to each other.
Khaled Osati; Hamed Joneidi; Nahid Azizi
Abstract
Prediction of rangeland species forage yield is one of the most effective tools for planning and policymaking of natural resources in each country. Climate variables (precipitation and temperature) play an important role in forecasting rangeland species production. In the present study, the forages yields ...
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Prediction of rangeland species forage yield is one of the most effective tools for planning and policymaking of natural resources in each country. Climate variables (precipitation and temperature) play an important role in forecasting rangeland species production. In the present study, the forages yields of some typical species in Ghoosheh rangeland, Semnan, measured using cutting and weighing method. It was evaluated in 30 plots with an area of two square meter, distributed along with two transect lines, for a 10-year period (water year 2005-2006 to 2014-2015), to determine the effects of drought on the forages yield of typical species in the studied areas. In the next step, several drought indices were calculated. The relationship between forages yield of rangeland species and drought indices values investigated to model forages production of study areas via drought indices. According to the values of drought indices SIAP, PNPI and Z-Score, several drought and wet-year periods occurred during the assessed 10-year. The relationship between forages production and drought indices confirmed that the best simple linear regression model for estimating total forages production of studied area was introduced by SIAP and Z-Score indices (RRMSE = 0.1) explaining 53% of production changes at 95% confidence level. The effects of drought and wet-year periods varied among different species so as to the annual production varied greatly for annual species (between 1 and 11% of total annual forages yield) and slightly for perennials and shrubs.
Moselm Rostampour; Effat Akbari; Mohammad Saghari
Abstract
The seed planting depth is one of the most important factors affecting the uniform plant emergence and the success of planting. This research was designed to determine proper seed planting depth for Atriplex canescens . in the nursery of the General Department of Natural Resources and Watershed Management ...
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The seed planting depth is one of the most important factors affecting the uniform plant emergence and the success of planting. This research was designed to determine proper seed planting depth for Atriplex canescens . in the nursery of the General Department of Natural Resources and Watershed Management of South Khorasan , allowing desirable seedlings with better vegetative properties to spend less cost in nurseries can be produced.For this purpose, after the collection and preparation of Atriplex canescens, seeds and pots, 15 seeds were selected and planted at 5 depths: 1, 2, 3, 4 and 5 cm with 5 repetitions. After the planting , the emergence percentage and vegetative traits of the seedling were measured. The data was analyzed by ANOVA and t LSD test. The results showed that with increasing seed planting depth, all the properties of the study were significantly reduced , at a minimum depth of 4 and 5 cm. The highest emergence percentage (34.7 % and 34.3 %) was observed at the depth of 1 and 2 cm and the lowest seedlings emergence percentage was observed at the depths of 4 and 5 cm (2.4 %). Since there is no significant difference between the emergence percentage, vigor index, and seedling stem length and weight, and the moisture content of the Atriplex canescens at the depths of 1 cm and 3 cm, Due to greater seed losses at the soil's surface depth by granivores such as insects and birds, as well as rapid drying of soil due to severe evaporation of water in the pot, A. canescens seed planting is recommended at a depth of 3 cm.
