Mohammad Reza Sayadi; Mehdi Ghorbani; Mohammad Jafari; Hamidreza Keshtkar; Leila Avazpour
Abstract
The objective of this paper is to identify the factors affecting the medicinal plant supply chain in the Nadushan region using a Glaser approach. The research method is applied in terms of purpose and qualitative in terms of method based on grounded theory and Glaser approach (emerging approach); and ...
Read More
The objective of this paper is to identify the factors affecting the medicinal plant supply chain in the Nadushan region using a Glaser approach. The research method is applied in terms of purpose and qualitative in terms of method based on grounded theory and Glaser approach (emerging approach); and it is exploratory based on the nature of the data and the use of inductive philosophy. The study population consisted of experienced local people and managers and experts in the field of the medicinal plant supply chain with more than five years of experience. Participants were selected using purposeful sampling and theoretical judgment. The data collection method was fieldwork, and the data collection tool was in-depth and structured interviews with 30 participants, including native farmers (15), researchers and experts (10), and intermediaries (5) in the field. The grounded theory approach was used to analyze the data and identify the key factors affecting the supply chain. The results identified 9 selective codes and 41 core codes. The factors affecting the supply chain include climate and weather, the region's high potential for medicinal plant cultivation, initial budget and capital, storage conditions, institutional support, policy, medicinal plant production and harvesting management, medicinal plant processing management, and the use of healthy practices in productivity. Therefore, ensuring a sustainable and efficient supply chain is crucial for maintaining the quality, availability, and affordability of medicinal plants.
Golnoosh Savartondrow; Salman Zare; Khaled Ahmadaali; Mohammad Jafari
Abstract
Due to the lack of water in the deserts of Iran and the high rate of evaporation, the establishment of vegetation and their irrigation are associated with many problems. Therefore, in the management programs for the sustainable development of dry and desert areas, it is very necessary to use less water. ...
Read More
Due to the lack of water in the deserts of Iran and the high rate of evaporation, the establishment of vegetation and their irrigation are associated with many problems. Therefore, in the management programs for the sustainable development of dry and desert areas, it is very necessary to use less water. Among these methods, deep subsurface irrigation using PVC pipes can be mentioned. In this study, a hole with a depth and diameter of 50 cm was dug, and then two pipes were mutually placed at a distance of 20 cm from each other on both sides of the pit. After placing the pipes, the pit was filled with soil. The wetting pattern in eight treatments has been examined in terms of the location of the water exit holes, the diameter of the pipe, the number of holes in the upper and lower half of the pipe, as well as the diameter of the holes. The results demonstrated that pipes with a diameter of 12.5 cm and a height of 55 cm, with five double rows of 6 mm holes in the upper half of the pipe at a distance of 3 cm from each other and two holes in the lower half of the tube at a distance of 10 cm from each other, The best depth of wetting pattern is created. The depth of the wetting pattern created in the soil around the plant root as a representative of water use efficiency is very important in the management and correct use of water resources as well as encouraging the plant to take deep roots. .
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 ...
Read More
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.
Reza Erfanzadeh; Mohammad Jafari; Misagh Ghasempour
Abstract
This study aimed to investigate the effect of Juniperus sabina (evergreen) and Berberis integerrima (deciduous) and herbaceous patches on some soil properties (pH, EC, aggregate stability, microbial respiration, organic carbon and nitrogen) in their habitats. In June, when maximum growth of the dominant ...
Read More
This study aimed to investigate the effect of Juniperus sabina (evergreen) and Berberis integerrima (deciduous) and herbaceous patches on some soil properties (pH, EC, aggregate stability, microbial respiration, organic carbon and nitrogen) in their habitats. In June, when maximum growth of the dominant plant species in rangelands of central Alborz was occurred, of each plant patch, 10 patches were randomly selected and soil were collected beneath of the canopy species in each from two depths: 10-0 and 20-10 cm (in total 60 soil samples). Then, soil physico-chemical characteristics were measured in the laboratory. In order to examine the differences between each soil characteristics associated with patches and depths, two-way ANOVA using GLM was applied. In addition, one-way ANOVA and post-hoc tests were used to compare soil characteristics between patches, in each depth separately. The results showed different effect of different patches on the soil characteristics. In upper soil layer, the highest contents of organic matter (4.62%) and aggregate stability (36.08) were observed under J. sabina, while the highest total nitrogen was found under B. integerrima. In deeper soil layer, the highest content of organic matter (5.19%) was found under J. sabina. The highest microbial respiration contents in both depths were observed under herbaceous patch. The variation of other soil characteristics were less pronounced by type of patches. In general, the results of this study cleared that different woody plant species have different effects on soil characteristics, should be mentioned in the rangeland development and improvement projects.
ِAli Tavili; S. Motahareh Hosseini; Mohammad Jafari; Ali Golkarian
Abstract
MAXENT model was used to evaluate the probability of Dorema ammoniacum development in rangelands of Southern Khorassan. Presence data of D. ammoniacum was recorded based on field survey and GPS application. Nine environmental information layers were used to model potential habitat of the understudy species. ...
Read More
MAXENT model was used to evaluate the probability of Dorema ammoniacum development in rangelands of Southern Khorassan. Presence data of D. ammoniacum was recorded based on field survey and GPS application. Nine environmental information layers were used to model potential habitat of the understudy species. Relationship between species presence and environmental parameters was determined using maximum entropy. Map of species distribution was achieved. Results showed that the probability of D. ammoniacum is higher in regions with the following environmental characteristics; elevation of 1017-1933 m, average temperature of 13.96 to 15.17 ºC, average precipitation of 112- 131 mm, slope of 0-14% and LST range between -4 to 10 ºC. An AUC of 92 demonstrated that MAXENT is a suitable model for prediction of D. ammoniacum distribution and potential habitat.
Rezaali Domehri Vasati Kolaei; Mohammad Jafari; Hossein Arzani; Seyed Akbar Javadi; Mahmood Arabkhedri
Abstract
The purpose of this study was to compare the condition and management of rangeland before and after replacing the soil condition assessment method in the soil factor of the four-factor method in order to determine the most appropriate rangeland condition method. Rangeland status assessment was performed ...
Read More
The purpose of this study was to compare the condition and management of rangeland before and after replacing the soil condition assessment method in the soil factor of the four-factor method in order to determine the most appropriate rangeland condition method. Rangeland status assessment was performed for both conditions in Poshtkuh rangelands of Mazandaran and then the status, rangeland management methods and their management and improvement programs were proposed and compared with each other. The results of rangeland condition assessment before replacing the soil condition assessment method in soil factor showed that rangelands had poor and very poor condition with a negative tendency and artificial rangeland management method and rehabilitation programs, mulching and seeding were proposed. The results of rangeland condition assessment after replacing the soil condition assessment method in the soil factor showed that the rangeland condition was in the middle and poor class, for which natural and artificial rangeland management methods were proposed, respectively. For the natural rangeland method, periodic-delayed and periodic-rest grazing systems were proposed based on the average status of the rangeland, and the breeding programs of the artificial rangeland method have not changed and are the same as the previous method. The results of comparative statistical analysis showed that there was a significant difference between the mean score of soil factor before and after replacement in the 95% confidence interval, . This method can be used as a method based on quantitative-qualitative evaluation to identify the functional and structural characteristics of ecosystems.
Setareh Bagheri; Reza Tamartash; Mohammad Jafari; Mohammad Reza Tatian; Arash Malekian
Abstract
Plain ecosystem is highly vulnerable to environmental changes, and drought is the most famous ecosystem change driver that is difficult to identify after its occurrence. In this research, to study the slope of vegetation changes against drought, the NDVI index of MODIS images and the SPI index from 2001 ...
Read More
Plain ecosystem is highly vulnerable to environmental changes, and drought is the most famous ecosystem change driver that is difficult to identify after its occurrence. In this research, to study the slope of vegetation changes against drought, the NDVI index of MODIS images and the SPI index from 2001 to 2016 were used and the map of vegetation changes against drought with five drought stress classes included very low classes, Low, moderate, high and very high, so that a suitable assessment of the drought can be made at specified time scales. The results of slope pattern of spatial change of vegetation against drought showed that across the plain vegetation changes have declined, and from east to west of Qazvin plain, the slope of vegetation changes and land susceptibility to drought have been reduced. So that the most percentage of area in a one-month drought related to the drought class is very low, but in droughts of 3, 6, 9, 12, 24 and 48 months, the highest percent of the area belonged to moderate and high drought classes. The results of this study, the determination of the level of vegetation changes in against drought in the past years and prediction of these changes in the future years, can be used in the planning and optimal use of resources, control changes in the future.
Raziyeh Dehghani; Mohammad Jafari; Mohammad Ali Zare Chahouki; Salman Zare; ِAli Tavili; Babak Moteshrezadeh
Abstract
The use of biochar as a soil amendment is one of the new methods to improve soil properties and increase plant yield. In this study, in order to evaluate the effect of adding natural biochar on soil properties and yield of Pamirian winterfat (Eurotia ceratoides) plant, an experiment in a completely randomized ...
Read More
The use of biochar as a soil amendment is one of the new methods to improve soil properties and increase plant yield. In this study, in order to evaluate the effect of adding natural biochar on soil properties and yield of Pamirian winterfat (Eurotia ceratoides) plant, an experiment in a completely randomized design were performed with 11 treatments by different levels of biochar (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10% by weight) and three replications in greenhouse conditions. After the end of the growing season, some physical and chemical properties of the soil (pH, EC, organic matter (%), lime, bulk deisty, particle density, and porosity percentage), germination percentage, and yield of E. ceratoides were measured. In all the studied traits of the soil (except for the particle density), and the characteristics of the E. ceratoides plant, the statistical difference between the various levels of biochar was significant (a = 0.01). Adding different levels of biochar increased pH, ECy, soil porosity percentage, soil organic matter, whereas decrased bulk density, lime percentage, clay percentage, sand, and silt.
Shiva Eyvazi; Sasan Babaei Kafaki; Mohammad Jafari; Mohammad Tahmoures
Abstract
Water, soil, pasture, forest, etc. are a valuable divine deposit for the people of any society and the national wealth of that society, which not only should be tried to preserve and protect these national assets, but should By adopting principled, technical, and regenerative exploitation policies, it ...
Read More
Water, soil, pasture, forest, etc. are a valuable divine deposit for the people of any society and the national wealth of that society, which not only should be tried to preserve and protect these national assets, but should By adopting principled, technical, and regenerative exploitation policies, it passed on these most precious sources of life to future generations. With the increasing power of technologies in the exploitation of natural resources, the environmental-environmental balance in recent centuries has been disturbed to the detriment of nature, which has created miserable and sometimes irreparable conditions and is referred to as the crisis of natural resources and the environment. It becomes. Today, the international community sees the solution to this dilemma as protecting the environment, and in doing so, wants to know how it can draw on religious teachings in this important matter. The mentioned research seeks to answer this question by descriptive-analytical method. The results show that in order to get rid of the current environmental crisis, we must refer to moral principles and religious texts, especially Islam, because the basis of the crisis in renewable natural resources is the moral crisis among humans and attention to the fundamental values of Islam. Due to its divine and moral support, it plays a key role in the sustainability and protection of the environment and renewable natural resources.
Mohsen Asadollahi; Mohammad Jafari; vahid sayare; Ali esmaeili; Mohammad Tahmoures
Abstract
Wind erosion is one of the most important aspects of land degradation in arid and semi-arid regions, which 20% of land area of the world has been influenced by wind erosion. The wind increases the desertification process by displacing sand dunes. Therefore, the stabilizition and preventing the moving ...
Read More
Wind erosion is one of the most important aspects of land degradation in arid and semi-arid regions, which 20% of land area of the world has been influenced by wind erosion. The wind increases the desertification process by displacing sand dunes. Therefore, the stabilizition and preventing the moving sands is essential. A strategy to combat this phenomenon is to reduce wind speed or to increase surface cover and soil resistance against erosion winds. The application of mulch or soil cover is one of the methods widely used to stabilize moving sands. For this purpose, a study was done at the Research Station International Desert Research Centre in Kashan city. The main purpose of this study was to investigate the effect of Multivariate biopolymer treatment at three concentrations (15%, 30% and 60%) on the moisture content of three sand depths (first depth of 0-5 cm, second depth of 5-10 cm and depth of third 10-20 cm), and study this mulch Compared with levels without mulch on the sand. Results showed soil moisture retention in Mulching compared to the control treatment, and statistically, there was significant differences between different depths of soil moisture Mulching compared to the control treatment and in between the first, second and third depths, the first depth had the highest increase in moisture holding compared to the Control treatment.
Shahram Yousefi Khanghah; Hossein Azarnivand; Mohammad Ali Zare Chahouki; Mohammad Jafari; Hamidreza Naseri
Abstract
The establishment of vegetation is the best way to manage degraded and at risk of degradation lands. Considering that the planting in arid lands is very costly because of ecological restrictions, so experts are looking for methods that increase the percentage of the seedlings establishment and reduce ...
Read More
The establishment of vegetation is the best way to manage degraded and at risk of degradation lands. Considering that the planting in arid lands is very costly because of ecological restrictions, so experts are looking for methods that increase the percentage of the seedlings establishment and reduce the cost of planting, in this regard the correct use of amendments is very important. The study area is located in Nazarabad City in southwest of Alborz province. In this study, the amendments including mineral biochar, arbuscular mycorrhiza fungi and acrylic resin polymer each in four levels were used at the base of Nitraria schoberi seedlings. The soil characteristics of the area was determined at the start of planting. After one year with counting the number of live seedlings, the percentage of establishment for each treatment was calculated. Economical estimates were calculated based on cost-benefit and calculated separately for each treatment. The results showed that there was a significant difference at the 5% level between the amendments and the control. Mycorrhizae had the highest (70%) and the control and biochar 4 treatments had the least (40%) percent of establishment. Economically, mycorrhizal 2, polymer 2 and biochar 1 treatments were the most optimal treatments for each amendment, respectively. The used amendments had different effects on the establishment of seedlings, so that the percentage of establishment increased with increasing level of mycorrhiza use, but with increasing level of polymer and biochar use, negative effects were observed and the percentage of seedling establishment decreased.
maede nasry; Mohammad Jafari; Hossein Azarnivand; Hamed Rafiee
Abstract
This study aims to examine the role and value of local community awareness of the economic value of carbon sequestration as an important rangeland ecosystem services in order to increase the participation of local community for conservation of rangeland. In order to explain the role and value of awareness ...
Read More
This study aims to examine the role and value of local community awareness of the economic value of carbon sequestration as an important rangeland ecosystem services in order to increase the participation of local community for conservation of rangeland. In order to explain the role and value of awareness in increasing the participation of people in both experimental and control groups, Contingent Valuation Method and dichotomous choice – double bounded format was used and willingness of local communities to pay to preserve pastures were measured. The results showed in two separate groups have a significant difference in terms of willingness to pay for conservation of rangeland, that the difference between the willingness to pay represents the exact value of awareness in increasing willingness to pay for conservation of pasture. In the experimental group, the average willingness to pay was 89410.84 Rials and in the control group average, the average willingness to pay was 32560.88 Rials. The difference between the average willingness of people to pay in two groups is the equivalent of 57039.12 Rials. The average willingness of people to pay each year in the village of test and control group respectively is 2587230.6 and 1657100.05 Rials. The proposed knowledge up to local communities in the Malard County of the carbon sequestration process as well as the role and its position in relation to the welfare of local communities, especially with regard to the beginning of the implementation of the International Generalized Carbon Sequestration in the county take priority.
Saeed Pourheadari; Hassan Ahmadi; ِAbolfazl Moeini; Sadat Feiznia; Mohammad Jafari
Abstract
Due to physical and chemical composition and lack of vegetation cover and therefore less organic matter, Marlons formations are the most sensitive formations to erosion, so that by removing the particles of the soil and transporting their to the lower regions, cause different forms of erosions. Due to ...
Read More
Due to physical and chemical composition and lack of vegetation cover and therefore less organic matter, Marlons formations are the most sensitive formations to erosion, so that by removing the particles of the soil and transporting their to the lower regions, cause different forms of erosions. Due to the physical and chemical properties of marls, the study area has caused various types of erosion in the basin and downstream urban areas has been affected followed by mudflows resulting from their erosion and sedimentation. In this research, 35 soil samples were taken from the different work units to determine the physical and chemical characteristics and also to study the soil losses using a rain simulator. Along to this, 5 samples from particular marl units of the area was taken and transferred to the laboratory for mineralogical experiments. The K method in the global erosion equation was used to evaluate the degradability of detached materials that according to this method, the highest value of k is related to forms with a coefficient of 70%, and the least of which is the surface and rainfall erosion form with a coefficient of 25%. Also, due to the fact that there were 4 units of work with attached materials, the stripy method was used to evaluate their erodibility.
Mahroo Dehbozorgi; Mohammad Jafari; Arash Malekian; Gholamreza Zehtabian; seyed rashid fallah shamsi
Abstract
In Iran, due to arid and semi-arid weather conditions the optimal use of limited water and soil resources has a particular importance. Land degradation is the result of incorrect policies in land management, which is a prominent example in the Bakhtegan watershed. Human factors, as well as climate changes ...
Read More
In Iran, due to arid and semi-arid weather conditions the optimal use of limited water and soil resources has a particular importance. Land degradation is the result of incorrect policies in land management, which is a prominent example in the Bakhtegan watershed. Human factors, as well as climate changes and the phenomenon of drought in recent years, have caused the area to be severely degraded in terms of water and soil resources and the life of Bakhtegan wetland has been subject to destruction. In this study, it was tried to identify natural and ecological factors as well as human parameters affecting the destruction and vulnerability of the area using fuzzy classification method and hierarchical analysis method (AHP) as well as the capabilities of GIS modeling, the data from the criteria and effective layers have been used and the level of vulnerability and land degradation has been determined. According to the results of the research, the level of land degradation and instability in the area has a large extent (48% of the area), However, the level of vulnerability in the central and downstream regions of the watershed and often in areas affected by human factors such as high population density, consumption of water in the agricultural sector, improper management of land use in the region, as well as dams and dike construction, has been increased. It was also concluded that human parameters have a more significant role in the degradation and vulnerability of the region compared to ecological and environmental factors.
Saeedeh Khaghani; Hossein Azarnivand; Mohammad Jafari; Abdollah Mollafilabi; Ali tavili
Abstract
This experiment was conducted as a split-plot factorial based on a randomized complete block design with three replications in the medicinal plants' farm of Islamic Azad University in 2017. In this experiment, water stress was considered as the main factor in four levels of irrigation including 100%, ...
Read More
This experiment was conducted as a split-plot factorial based on a randomized complete block design with three replications in the medicinal plants' farm of Islamic Azad University in 2017. In this experiment, water stress was considered as the main factor in four levels of irrigation including 100%, 75%, 50% and 25% of the plant water requirement in the main plots. In addition, the application of different levels of zeolite (including no application of zeolite, two, four, six tons per hectare), as well as application of salicylic acid at two levels (0.5 and 1 mM) were considered as secondary factors in the form of factorial on subsidiary plots. The results showed that the effect of different levels of water stress on the traits such as plant height, number of lateral branches, plant wet weight, leaf area index, number of flowers in inflorescence was significant at 1% and on plant dry weight was significant at 5%. Salicylic acid application was also significant on some traits such as flower number in inflorescence, leaf area and dry weight at the probability level of 1%, and on plant volume and wet weight at 5% level. In addition, the effect of different levels of zeolite application was significant on plant height, number of lateral branches, wet weight, dry weight, leaf area index, number of flower in inflorescence at 1% level.
Shima Javadi; Gholamreza Zehtabian; Mohammad Jafari; Hassan Khosravi; Azam Abolhasani
Abstract
The reduction of soil quality and health due to the lack of proper management or land use change in arid and semi-arid regions of Iran has become a major challenge, which affects the nutritional properties of the soil. Regarding to the importance of nutrients in plant growth, the aim of this study was ...
Read More
The reduction of soil quality and health due to the lack of proper management or land use change in arid and semi-arid regions of Iran has become a major challenge, which affects the nutritional properties of the soil. Regarding to the importance of nutrients in plant growth, the aim of this study was investigation and comparison of soil nutrients under different agricultural land uses in Eshtehard region. At first, different maps of region including soil map, elevation and land use maps were prepared using ArcGIS 9.3. Five land uses including garden lands, monoculture lands, multiple cropping lands, fallow lands and rangelands were recognized as the treatments. After sampling the soil, nutrients including N, Ca, Mg, K, P were measured in two depths of 0-30 cm and 30-60 cm. In addition, the amount of ESP, as a destructive factor, was assessed in order to determine the corrective or destructive role of different land uses. The results of statistical analysis of data using SPSS software showed that there was a significant difference between nutrients average. In addition, the results showed that rangelands and garden lands had the corrective role in surface and deep layers respectively and monoculture lands had destructive role in the deep layer. Follow lands had the most destructive role in both surface and deep layers. Generally, garden lands, rangeland and multiple cropping lands were determined as the most desirable treatments and follow lands and monoculture lands were determined as the most undesirable treatments.
sadegh hoseinniaee; Hossein Azarnivand; Mohammad Jafari; Mohammad Ali Zare Chahouki
Abstract
Haloxylon is one of the resistant plants in desert areas, which has always been considered by researchers and practitioners since controlling sandy soils as one of the solutions to erosion and sand fixation by biological methods. In this study was conducted in forest plantations eshtehard, Bases of haloxylon ...
Read More
Haloxylon is one of the resistant plants in desert areas, which has always been considered by researchers and practitioners since controlling sandy soils as one of the solutions to erosion and sand fixation by biological methods. In this study was conducted in forest plantations eshtehard, Bases of haloxylon thate wilting and drying effects are visible, was chosen and pruning them. This factorial experiment based on completely randomized design with four treatments, pruning time (September, October, December, February) and four sub-plots pruning height (Complete pruning, 25 cm, 50 and 75 cm) were implemented. Before applying pruning, for homogeneous and the same size the bases, Variable height, canopy cove diameter and crown diameter was measured on every base. The end of July condition bases was investigated in terms of Tillering and not tillering. Results showed that pruning stimulates been tillering. Because 97.5 percentage of bases was tillering. Pruning in January from height of 75 cm with 100 tiller hade the greatest number tiller. The lowest tiller regarding of November with 5 tiller. There is no significant difference between treatments in term of tiller diameter, but in general thickest tiller was for pruning in January. Therefore, it can be said that pruning is about 75 centimeters in December as the best pruning time and heigh.
sadat Feiznia; ahmad reza mokhtari; mohammad jaaferi; mohammad javad ghanei bafghi; ziba khodayian
Abstract
Mining and its various stages is one of the important factors in spreading pollution in natural environments. Contaminations may affect soil and water resources and actually enter the food chain due to absorption by plants. Among mineral elements, lead is more important because of its toxic effects. ...
Read More
Mining and its various stages is one of the important factors in spreading pollution in natural environments. Contaminations may affect soil and water resources and actually enter the food chain due to absorption by plants. Among mineral elements, lead is more important because of its toxic effects. In order to investigate distribution of lead in downstream soils of Kushk Lead and Zinc Mine and identify anthropogenic and geogenic natures of pollution spread, a classified random systematic sampling was carried out. Sampling interval was 500 to1500 meters and soils were sampled in 0-5 and 5-30 centimeters depths. A control sample area with similar characteristics was considered in the vicinity of the region. The samples were analyzed by ICP-MASS method and the lead content of the samples was determined. Using Enrichment Factor and Geoaccumulation Index, the extension and severity of pollution are determined and related maps are prepared. Conclusions show that average amounts of lead in topsoil is about 4 times of subsoil and one kilometer far from mine, lead content of soil is more than 290 PPM that is more than permissible amounts. Moreover, the difference between lead content in topsoil and subsoil shows that the contamination in these areas is anthropogenic. Contamination reduces by going further from mine and the highest amount of emission of lead is around the main watercourse.
Salman Zare; Mohammad Jafari; Hassan Ahmadi; Hasan Rouhipour; Reza Khalil Arjomandi
Abstract
In this regard, the present study aimed to evaluate the performance of some of the non-oil mulch to stabilize sand dunes in the Kashan's Rig-boland desert. monthly surveys are conducted in the desert areas. To evaluate the effect of mulch on stabilizing the sand dunes, the effect stabilization index ...
Read More
In this regard, the present study aimed to evaluate the performance of some of the non-oil mulch to stabilize sand dunes in the Kashan's Rig-boland desert. monthly surveys are conducted in the desert areas. To evaluate the effect of mulch on stabilizing the sand dunes, the effect stabilization index was used. The results indicate there is a significant difference between different mulch. The comparison test showed that the highest coefficient effect of stabilization with significant effect done on the biological mulch. After that, however, three other mulches including resins, inorganic and polymer are, respectively had the most significant effectiveness. Although there was not significant difference between these three types of mulches. Biopolymer Mulch with the lowest coefficient of stabilization effect showed significantly different from other mulches. Mulching in the hills with biological mulch, due to tightly crust formation against erosion, removal of sand and dunes almost stopped and hill completely has been stabilized. In this study, used mulches were initially very resistant and feasting the sands dune surface such as resistance crusts which were loss against any tensile and compressive force before mulching practices. . Therefore, different mulches treatments according to their durability and nature of structural have different effectiveness in reducing wind erosion effect. Among the studied mulches, just biological mulch and has usability and is capable for executive pilots.
nasibe ghanbari; hossein azarnivand; hamed joneidi jafari; mohammad jafari
Abstract
This study aimed to effect of converting rangeland to afforestation on carbon and nitrogen storage was done in forested areas of Hassan Abad in Sanandaj. Masses of studied was include Cupressus arizonica, Pinus eldarica, Fraxinus rotundifolia, Robinia psedoacacia and Thuja orientalis whit an average ...
Read More
This study aimed to effect of converting rangeland to afforestation on carbon and nitrogen storage was done in forested areas of Hassan Abad in Sanandaj. Masses of studied was include Cupressus arizonica, Pinus eldarica, Fraxinus rotundifolia, Robinia psedoacacia and Thuja orientalis whit an average age of 20 years and adjacent rangeland that converting was not created was selected as control. Sampling of soil was done in afforestation mass and control and characteristics of organic carbon, nitrogen, phosphorus, potassium, bulk density, pH, electrical conductivity, percent clay, silt and sand was measured. To compare the effect of forestry corrective operations on carbon sequestration was used independent t-test analysis and to compare the effects of different types of afforestation on soil carbon and nitrogen sequestration rates was used one-way ANOVA. Results shows that Robinia psedoacacia have a significant effect on increase of carbon and nitrogen sequestered and amount of phosphorus and potassium in soil and in total in Robinia psedoacacia mass amount of cabon sequestered and nitrogen stored in soil was calculated 80.62 and 5.42 ton/ha and in control 47.05 and 3.08 ton/ha and Robinia psedoacacia mass cause to increase of soil carbon and nitrogen amount of 71 and 75 percent and lowest amount of carbon and nitrogen was obtained in soil of Cupressus arizonica mass. Stepwise regression results showed that nitrogen, phosphorus and potassium, respectively are most important components affecting in soil of investigated mass.
Fatemeh bahreini; Fatemeh Panahi; Mohammad Jafari; Arash Malekian
Abstract
The complexity of drought phenomenon hinders our full understanding of its impact. Field sampling, Geographic Information Systems, SPI and NDVI, EVI and SAVI indices derived from 16-day interval MODIS images during 2000-2015 were used to better understand the effects of drought on vegetation In recent ...
Read More
The complexity of drought phenomenon hinders our full understanding of its impact. Field sampling, Geographic Information Systems, SPI and NDVI, EVI and SAVI indices derived from 16-day interval MODIS images during 2000-2015 were used to better understand the effects of drought on vegetation In recent study, ground true map was prepared by sampling and field surveys and vegetation cover data was obtained from 32 sampling units in 320 plots over the entire study area. Then, the correlation between field sampling data and vegetation indices was estimated and vegetation cover models were produced for different indices. In this study, precipitation data of 14 stations within and around the study area were used and SPI was calculated at the same time scales with the vegetation indices to study the effect of drought on vegetation. The results showed that NDVI has had the highest correlation coefficient (R2=0.56) amongst the indices so it was selected for vegetation cover percentage mapping. Investigating NDVI rates and drought index in different temporal periods, 9-month SPI was found to have the best correlation with NDVI. On the basis of SPI analysis, it was found that the study area had the most severe drought in 2012 and the best wet condition in 2004. The similar trend was observed in NDVI. The comparison of classified images between 2004 and 2012 (with 42 % changes in poor vegetation) indicates the effect of drought on vegetation in the study area.
Bakhtiar Fattahi; Mohammad Jafari; Soheila Aghabeigi Amin; mahdieh salehi; ayoub karimi; Azad Karami
Abstract
Abstract This study aimed to investigate the effect of different intensities of grazing on soil chemical properties on Gonbad paired basins-Hamadan. The objective of this research was to characterize the impact of sheep grazing intensity on soil chemical behavior on mountainous in Hamadan rangelands ...
Read More
Abstract This study aimed to investigate the effect of different intensities of grazing on soil chemical properties on Gonbad paired basins-Hamadan. The objective of this research was to characterize the impact of sheep grazing intensity on soil chemical behavior on mountainous in Hamadan rangelands (Gonbad paired basins). Grazing intensity was classified as light, moderate and heavy, then the soil samples from the three depths of 0-10, 10-20 and 20-30 cm were collected. The soil data was analyzed via SPSS (ANOVA). Results showed that the soil OC, total N content and organic matter decreased significantly with grazing intensity and they were greatest at the surface and decreased with depth. The amount of Calcium and Magnesium won't be affected by grazing intensity. The decreases in soil OC suggest Carbon storage in the soil of grassland declined as grazing intensity increased. Combined with the decreases in soil TN content, this also means heavy grazing could lead to decreases in soil quality and fertility. Uneven grazing intensity is an inherent feature of a season long-grazing system and there are risks to avoid quality and environmental health.
Khosro Shahbazi; ali salajagheh; mohammad jafari; hassan ahmadi; ali akbar nazari samani; mohammad khosro shahi
Abstract
Negative impacts of gully erosion in marl areas are severe due to improper landuse practices such as irrigation, tillage, overgrazing and degradation of vegetation cover. The objective of this research was to evaluate hydraulic flow thresholds of gully erosion in the agriculture (AG), fair rangeland ...
Read More
Negative impacts of gully erosion in marl areas are severe due to improper landuse practices such as irrigation, tillage, overgrazing and degradation of vegetation cover. The objective of this research was to evaluate hydraulic flow thresholds of gully erosion in the agriculture (AG), fair rangeland (FR) and poor rangeland (PR) areas in the Qasre-shirin, Kermanshah, Iran. Nine flumes were performed in the field to determine the critical values of hydraulic parameters including flow discharge, velocity, Froude and Reynolds numbers, Darsi resistance coefficient, shear tension, head-cut dimensions as well as vegetation cover. Results showed that respective critical value of discharge as the gulling thresholds for AG,FR and PR was 1.53, 12.0 and 4.49 li/s indicating significantly higher (p<0.05%) in the FR due to higher vegetation cover. In addition, there were no significant differences for flow disturbance based on Froude number, while the respective value of Rinuldze number in the AG, FR and WR were obtained 3113, 26092 and 9525 significantly higher in the FR. Furthermore, the critical level of shear tension for gully formation in the AG, FR and WR were found 12.12, 14.01 and 9.28 Nm-2, respectively showing significant differences among them. Finally, it is concluded that hydraulic flow parameters as the gully triggering are strongly affected by vegetation cover through landue practices so that higher plant cover in the FR was the key factor resulting in significant enhancement of gully.
seyed akbar javadi; alireza khanarmooyi; Mohammad Jafari
Abstract
The relationship between vegetation and soil properties in Khojier National park, located in Tehran province was investigated. For this purpose, vegetation data was recorded in each plot, based along 3 tansects in each vegetation type. Minimal area method was used for plot size. Density and vegetatin ...
Read More
The relationship between vegetation and soil properties in Khojier National park, located in Tehran province was investigated. For this purpose, vegetation data was recorded in each plot, based along 3 tansects in each vegetation type. Minimal area method was used for plot size. Density and vegetatin cover were determined. TWINSPAN and DCA tests were used to classify vegetation. Soil sample was taken from 0-20cm of soil depth then transferred to laboratory and prepared for analysis including soil texture, percentage of CaCo3, CaSo4, and pH, EC, P, Ca, Ma and N. For analysis of soil properties in relation to vegetation changes, a multivariate analysis method such as canonical correspondence analysis (CCA) was used. These analyzes were conducted using PC-ORD software. Results showed a significant correlation between vegetation and environmental factors. The most important soil properties affecting on vegetation types were gravel, clay, silt, sand, caso4, caco3, pH, EC, K and elevation. Statistical analysis of the results showed that the vegetation types had a significant difference in terms of percentage of Gravel, CaCo3, CaSo4, Sand, Clay.The most important soil properties affecting on vegetation types were gravel, clay, silt, sand, caso4, caco3, pH, EC, K and the height above sea level. Statistical analysis of the results showed that the vegetation types had a significant difference in view of percentage of Gravel, CaCo3, CaSo4, Sand, Clay.
Mohammad Jafari; Hossein Azarnivand; Ahmad Sadeghipour; Nadia Kamali; Ahmad Heidari; Hassan Maddah arefi
Abstract
Global warming and climate change have drawn special attention to soil and its potential for stable carbon sequestration. Soils are the largest stores of carbon in terrestrial carbon cycle and contain about three times more carbon than vegetation cover and two times more than that of atmosphere. Studying ...
Read More
Global warming and climate change have drawn special attention to soil and its potential for stable carbon sequestration. Soils are the largest stores of carbon in terrestrial carbon cycle and contain about three times more carbon than vegetation cover and two times more than that of atmosphere. Studying the effects of grazing on soil carbon storage is important because of the major role soil organic carbon has in production. Grazing is potent for changing the carbon storage of rangeland ecosystems. In this research, the effect of different grazing intensities on carbon sequestration and nitrogen stabilization in pastures cultivated with Atriplex canescens in Shahriar was studied. Soil and plant samplings were done in low, moderate and high grazing intensity areas as well as exclosure, using randomized – systematic method. Soil samples were taken from 0-10, 10-30 and 30-100 Cm depths of 20 soil profiles. In each soil sample, stone percent, bulk density, organic carbon and nitrogen were calculated. Data analysis was done using one – way ANOVA and Duncan test in SPSS 17 software. Results showed that all three grazing intensities have caused significant reduction in carbon and nitrogen of soil.
