مجید صادقی نیا

According to extent of rangelands and their role in capturing and storing atmospheric carbon dioxide, the present research has been investigated. Carbon sequestration between two regions under livestock and wildlife grazing in the plain areas of Mehriz in Yazd province. For this purpose, in order to determine the level of steppe desert vegetation in two wildlife and livestock grazing sites, sampling of this dominant plant and soil in each of these areas was done in a systematic random way. Sampling of 30 dominant species was done in simple steppe and after cutting the aerial organs (leaves and stems) and roots, they were weighed. Along with plant sampling in each plot, soil samples were collected to the depth of 50cm   near the plants. In laboratory, the organic carbon percentage of plant and soil samples was determined Data analysis was done in SPSS software. The results showed that aerial biomass carbon sequestration in both wildlife (7.56 kg/ha) and livestock (6.90 kg/ha) sites had a significant increase compared to underground biomass and stem had the highest amount (p<0.01). The amounts of root carbon storage in wildlife and livestock sites were obtained as 3.61 kg/ha and 3.47 kg/ha, respectively. Also, the amounts of carbon sequestration of plant organs in the area under livestock grazing was lower than that of wildlife. In wildlife site, the amounts of carbon storage in aerial, underground and total plant biomass were 7.56 kg/ha, 3.61 kg/ha and 11.17 kg/ha, respectively, while in livestock site was 6.91 kg/ha, 3.47 kg/ha and10.37 kg/ha. About the soil, also a significant decrease in the amount of carbon sequestered in livestock site (6.76 tons/ha)) was observed compared to wildlife site (10.33 tons/ha). So, Therefore, unprincipled and excessive livestock grazing can be introduced as an important factor in reducing carbon sequestration in the region.

The presence of stones and gravel on the soil surface affects the physical properties of the soil, playing an effective role in controlling water and wind erosion. However, while significantly contributing to the protection of soil, desert pavement is less used as a protective element in arid and extra-arid areas. on the other hand, as Iran is advancing its industrial development based on different natural fields, extensive land use changes lead to shallow soil mixing and the soil’s desert pavement, significantly increasing the erodibility of the soil due to the loss of the pavement’s protective shield. Consequently, the intensity of wind erosion and the dust that naturally arises from it will increase in the destroyed lands, leading to an increase in accident risks and personal and financial damages due to the reduction of visibility on highly traveled roads.

Field sampling and laboratory calculations: Thirty points were randomly selected in each plain where the required samples were collected from the desert pavement. Concurrently, the duration of sample collection was also calculated in each plot and transect. Then, the collected samples were transferred to the laboratory and tested separately in terms of granulation. Sediment samples collected from every plot and transect were separated into distinct size classes using the ASTM classification system. These size-separated sediments were then accurately weighed using precision balances. After sieving the samples and determining the weight of particles in different size ranges, the average weight of each sample at thirty specific points was calculated. Finally, the relative abundance, expressed as the percentage frequency of particle weight, was computed for each plot and transect based on the calculated mean weights. The results obtained from each plot and transect were then entered into the SPSS software. Using the least squares and Duncan tests to compare the samples collected from the plots and transects. It should be noted that the two tests are widely used for ranking averages in one-way variance analysis. One-way variance analysis evaluates the effect of a discrete variable with more than two levels on a continuous variable. If the null hypothesis is rejected in terms of significance level, the discrete variable is proved to exert an influence on the continuous variable. In the least squares test method, the average values are compared in binary oppositions, and in Duncan's method, the average values are divided into subgroups based on the specific value of α. The analysis of the results of these two tests shall also be performed in terms of significance level.Sampling time in each plot and transect was compared and evaluated using t-tests. It should be noted that the T-test is commonly used to compare two independent statistical samples, whose results may differ based on the equality/ inequality of the variances. Finally, the optimal method for measuring desert pavement was selected based on the results of the statistical tests and the significance level required for sampling in each plot and transect.Moreover, to compare the desert pavement samples collected from each plot and transect, 30 points were randomly selected in each plain. Then, the sampling of the desert pavement was carried out using a plot with 40x40 cm dimensions and a transect with 60x10 cm dimensions.

The results of Duncan's test revealed that the two categories of plot and transect were placed in the same ranking group, indicating that both methods produce the same results in the measurement of desert pavement. As the duration of collecting samples from each plot and transect was measured concurrently with the sampling, the time of collecting sampling from the plots and transects in different parts of each plain was evaluated and compared via T-Tests using the SPSS software. Moreover, the results of Lyon's test showed that the variances of the two groups ( plot and transect), were not the same, suggesting a significant difference between the time used in the plot and that of the transect. In this regard, the average time for the plot and the transect was found to be 1.64 and 0.83, respectively, indicating that the time spent for conducting the sampling in the transect was lower than that of the plot and that there was a significant difference between the two in this regard.On the other hand, to compare two independent samples of plot and transect, first, the two samples were evaluated using Levene's test, according to which the null hypothesis regarding the equality of the variance rates was rejected as the significance level turned out to be less than 0.05 (Sig> 0.05). The results of the T-test based on the hypothesis regarding the equality of the variance rate were also found to be zero in terms of significance level, indicating that the values found for the plot differ from those of the transaction, and thus the null hypothesis is also rejected in this case. As for the choice of a better sample in terms of the difference in the average value, it can be seen that the obtained value is positive (0.8), suggesting that the plot sampling time is longer than that of the transect. Therefore, it can be argued that collecting sampling from the transact would be less time-consuming than that of the plot, and thus it would be a better choice for measuring the desert pavement. Furthermore, the results showed that in terms of variance level, the two categories of plot and transect differ from each other, indicating a significant difference between the time used in the plot and that of the transect. Accordingly, the average time used in the plot and transact was found to be 1.64 and 0.83, respectively, proving that the time spent in the transect sampling method was lower than that of the plot and that there was a significant difference between the two in this regard.

Plot and transect methods were compared and evaluated in order to choose the most suitable method for measuring desert pavement. The results of the one-way analysis of variance showed that the sampling method may affect the weight frequency of the collected samples. Then, the average percentage of the frequency rates obtained for the plot and the transact were compared and ranked in binary oppositions using the LSD and DUNCAN tests. The results indicated that both sampling methods exert the same influence on the frequency percentage of the samples. Then the plot and transect methods were compared in terms of sampling time and level. Accordingly, as for the time spent on sampling, the samples were collected in a shorter time from the transect than from the plot. Moreover, it was found that the transect demanded a smaller area (0.06 square meters) for sampling than the one demanded by the plot (0.16 square meters). Therefore, it can be concluded that the transect method is more suitable for sampling the desert pavement in terms of area and time. Finally, it could be argued that the results of this study proved the high efficiency of the software in terms of the spatial resolution of the images and the average size of the riverbed sediments, which can significantly contribute to future development. Therefore, the abovementioned methods can be used as new methods in the study of desert pavement in a large area.

   The increasing trend of land destruction in many parts of the world is a serious threat to humanity. Desertification, which is one of the manifestations of this destruction, has affected most of the countries. What is certain is that today the phenomenon of land degradation and desertification in the world and especially in Iran is progressing rapidly and every day it is taking over more areas. The intended method in this research includes the laboratory use of 10 micron bentonite clay through a wind tunnel and determining its hardness by preparing a suspension on the surface of the windy sand; also using different percentages of this clay along with the cultivation of seedlings of Nitraria schoberi, which is resistant to salinity and dehydration. This method is of interest and can be a suitable moisture absorber for storing soil moisture and plant establishment, and also a good alternative to oil mulches that are harmful to the environment. Considering the importance of the problem of dust phenomenon as well as the crisis of drought and lack of water in Sajzi region of Isfahan city, the aim of this research is to establish vegetation cover in critical areas where there is no possibility of fighting except oil mulch or it is difficult to do so. More specifically, the experiment is done by using 10-micron bentonite clay in the pit of Nitraria schoberi seedling cultivation and sprinkling it on the surfaces of the harvesting and transportation area, while reducing the frequency of irrigation and reducing the amount of wind erosion.

In this research, which investigates the use of processed bentonite clay in moisture storage to control soil erosion, by adding this material to the soil, its ability to control wind erosion was investigated in the form of statistical analysis. Bentonite clay can be used with less volume and longer shelf life to control desertification. The 10-micron bentonite clay used in this research is homogeneous in water and can be used to control wind erosion on the soil surface; it reduces water consumption, increases seed germination and increases crop yield. Vegetation can be an effective factor in increasing the roughness of the soil surface and reducing the wind speed. The higher the density of vegetation and the longer its duration on the soil surface, the greater its role in preserving and maintaining the soil.

Effect of bentonite treatments on moisture content In the field experiments, a randomized complete block design was implemented, in which 10-micron bentonite with percentages of 2, 4, 6, 8 and control were used in the cultivation pits with the symbol of Nitraria schoberi seedling cultivation. Also, in 7 time stages of irrigation stress after cultivation (6 periods of alternating irrigation with intervals of 18 and 32 days) and the last irrigation period with an interval of 54 days, the soil sampling of the cultivation pits was done with an auger, and after being transferred to the laboratory, the percentage of moisture was determined. In this experiment, the effect of bentonite on the moisture level at the depths of 0-10 and 10-20 was statistically significant at the level of 1%. The results of comparing the averages showed that in the first stage of sampling to determine the percentage of moisture in the depths of 0-10 and 10-20 cm, with the increase of bentonite, the amount of soil moisture increased significantly. The highest percentage of soil moisture was observed in treatment 8 and the lowest in the control treatment. The amount of soil cell resistance According to the results of variance analysis of the data, the effect of bentonite treatments on soil hardness and erosion was significant at the level of 1 and 5%. Speed 5.7 was obtained in the bentonite treatment of 4 grams per liter and the lowest amount was obtained in the control treatment. In speeds 11 and 28, the highest soil cell resistance was observed in the treatment of 4 grams of bentonite and the lowest amount was observed in the control treatment.

Today, the phenomenon of wind erosion and its consequences is considered as one of the processes of land degradation in arid and semi-arid regions. The preliminary economic assessment of the use of 10-micron bentonite clay instead of other moisture absorbents in maintaining moisture and reducing irrigation frequency shows that this material is easier to access and the cost of its preparation is much lower. The positive effect of bentonite in reducing soil erosion can be due to the fact that bentonite is a clay mineral from the montmorionite family with expansion properties that is created by the weathering of volcanic ash. Also, due to its unique properties, it can be used in increasing the pulp index of the source soils. According to the results of this research, bentonite mineral can be effective in controlling the internal erosion of materials, so that the amount of erosion decreases with the increase of bentonite percentage. The results of this research on the reduction of erosion rate by increasing the bentonite percentage of the soil are consistent with the results of the research of Zumardian and Khushkho (2013). The results of this research showed that according to the method applied in random complete blocks, different treatments of bentonite had an effect on the moisture level and also on the hardness and erosion of the soil in the wind tunnel and shear vane stage. The effectiveness of the soil depends on the amount of bentonite used, the amount of moisture and wind speed, so with the increase in the amount of bentonite in the soil, the hardness and moisture of the soil increased as well.

The distribution and establishment of plant species are influenced by various environmental conditions. Calligonum bungei, a species of the genus Calligonum, is widely distributed in arid and semi-arid climates in Iran. This research aimed to investigate the environmental conditions governing the distribution of Calligonum bungei in the desert rangelands of Kerman province. The study focused on identifying different types of Calligonum bungei habitats, assessing canopy cover, density, and associated species, and examining the influence of environmental factors, such as climate, topography, and soil, on the species' distribution.

Four representative areas in Kerman province were selected to represent the dominant types of Calligonum bungei habitats. Geomorphological types were identified using satellite images and field visits. Environmental factors, including climate, topography, soil properties, and characteristics specific to the species (density, canopy cover, associated species), were evaluated in each habitat type. Vegetation studies were conducted along 300-meter transects, with plot sizes determined based on vegetation type and distribution (100 square meters). A total of 40 plots (10 plots per studied area) were investigated. Canopy cover was determined by measuring two perpendicular diameters of the plant canopy. Principal component analysis (PCA) using PC-ORD software was employed to analyze the relationship between environmental factors and species establishment in the study areas.

The results showed that Calligonum bungei was present in the altitude range of 1400-1750 meters, slopes ranging from 1% to 18.4%, and in all directions. The average annual rainfall in the areas varied from 55.5 to 163.4 mm, while the average annual temperature ranged from 16.7 to 26.4 degrees Celsius. The minimum and maximum absolute temperatures recorded were between -20.8 and 48.8 degrees Celsius, respectively. The average annual humidity ranged from 29.6% to 42.5%, and the length of the dry season varied from 8 to 12 months per year. Soil analysis revealed shallow soil with sandy-loamy to sandy-loamy texture, sand content between 67% and 84%, lime content between 8.5% and 20%, carbon content between 0.1% and 1.35%, nitrogen content between 0.0% and 0.7%, absorbable phosphorus between 9.5 and 13.5 milliequivalents, absorbable potassium between 200 and 217.5 milliequivalents, salinity between 0.36 and 1.02 decisimians, and pH values between 7.8 and 8.09. In terms of vegetation, Calligonum bungei was observed to be scattered in all studied areas, with densities ranging from 10 to 280 plants per hectare and canopy cover varying from 0.1% to 5.7%.

The principal component analysis revealed that the first component (annual temperature, humidity, sand, and silt) explained 46.9% of the variation, the second component (altitude, slope, annual rainfall, phosphorus, lime, and potassium) explained 35.3%, and the third component (clay, nitrogen, and salinity) explained 17.8%. Environmental factors influencing the establishment of Calligonum bungei varied among the studied areas. In Anar and Kerman regions, increasing sand content and decreasing annual temperature, humidity, and silt were significant factors. In the Bam region, increasing phosphorus and potassium content and decreasing altitude, slope, annual rainfall, and lime were influential. In the Jiroft region, reducing sand content and increasing annual temperature, humidity, and silt played a role. Overall, these findings indicate that the identified environmental factors act as limiting factors for the establishment of Calligonum bungei in the study areas.

The loss of vegetation and the prevalence of decay in Artemisia habitats due to climate change and management factors necessitate the need to focus on a conservation approach in the management of these ecosystems. In this regard, the effect of the conservation approach (exclosure with a history of 30 years) on the structural components of vegetation, soil characteristics, and values of numerical indicators of species diversity in the Artemisia habitats of the Dehno-Bardsir region was investigated. For this purpose, vegetation sampling was performed during the growing season of 2013 inside 45 two-square-meter plots located along three transects of 150 meters, inside and outside the enclosed area. Within each plot, the percentage of canopy cover of species was estimated and the number of their bases was counted based on the percentage of canopy cover of species, indices of species diversity were calculated. Along each of the transects, a composite soil sample was taken from a depth of 0-30, and their physical and chemical properties were measured. Based on the results, in terms of canopy cover percentage, only in the case of Stipa arabica, there was a significant difference between enclosed and non-enclosed areas. In terms of the number of bases per hectare, there was only a significant difference between Zygophyllum atriplicoides and Stipa arabica, and in terms of presence only between Artemisia sieberi, Stipa arabica, and Zygophyllum atriplicoides, there was a significant difference inside and outside the enclosure. In sum, the exclosure will cause Stipa arabica to dominate the area. There was no significant difference between soil properties (percentage of clay, silt, and sand, electrical conductivity, acidity of saturated mud, amount of lime, calcium, magnesium, and sodium) in the two places. The amount of species richness in the enclosure area (with 21 species) was higher than in the grazing area (with 16 species). The values of Simpson and Shannon-Weiner indices also indicate no difference between the two places for evenness and heterogeneity of vegetation. What is certain is that the results of three decades of exclosure showed that the process of vegetation change in the valleys of arid regions is slow. Applying a conservation approach in such ecosystems will be effective in the long run.

Pollinators that feed on insect-pollinated plants have an important role in the food chain. Because pollinator insects have the potential to raise the value of agricultural crops and are very helpful in the nitrogen stabilization and the prevention of pest invasions. The present study mainly investigated the contribution of three services of insect pollination in rangeland along with the valuation of the services. In the study, to calculate the share of each service, cutting and weighing methods (for forage production) and engineering economics methods (replacement cost and Transfer of Benefits) were used to calculate the economic value in 2017. These services include increased yield of agricultural supply, upgraded nitrogen fixation by nitrogen fixing plants in rangelands, and reduction of plant pests and diseases by pollinator insects. Each service value was anticipated to be 15.31%, 48.9% and 35.78% of the overall of insect pollination, respectively. Besides, the extent of pollinator insects services value per hectare and the whole rangeland ecosystem was 62.37$ and 649096.5$, respectively. Consequently, following the outcome of the present study, preservation of insect pollination services is considerable to sustain and keep food security, sustainable agricultural development, sustainable employment, and protection of natural, environmental ecosystems and the environment, especially rangelands. Thus, insect pollinator services were regarded significant by policy makers and managers.

Plant community’s classification provides an organization framework for design of future studies of the Functional features of communities or systems and the relationship between species and the environment of the studied region and since the plant species growing in an area are affected by environmental and biological factors on these regions, Therefore, identification and classification of vegetation distribution and climatic, soil and geomorphometry properties are necessary. In this research, vegetation Sampling was done by random-systematic method to place plots along four transects. In each plot, vegetation Cover information (name of plant species and percentage cover) was recorded, and at the beginning and end of each transect was digging the soil profile. Then, climatic and geomorphometry data were extracted. In order clustering regions based on climatic, soil, geomorphometry factors, was used hierarchical method and to calculate distance between clusters was used Ward's method. The results of regional clustering based on environmental factors showed that these results correspond with reality and areas with a zero percentage coverage of Artemisia sieberi in a cluster and areas with a moderate to high level of A. sieberi were found in other clusters. Generally, it can be concluded that there is a relationship between the environmental factors and the distribution pattern of the plants.

Barkhan is one of the most common forms of sand dunes and the influx of sands in the form of Barkhan hills is considered as one of the most important environmental hazards in most parts of Iran, which will cause a decrease in the quality and quantity of groundwater, reduce soil fertility and increase the susceptibility of lands to erosion and landslides. Therefore, their comprehensive identification is very important. The aim of this study was to investigate the granulometric characteristics of Ardakan Barkhans in different heights. In 2016 the study area was identified using Satellite Images and Google Earth software, then, with a field visit to Ardakan region, sampling was done from 6 Barkhan at two different heights.In the next step in the laboratory, granulometric operations were performed on the samples. Then, by performing independent t-test, the significance of the difference of each variable was investigated. The results showed that the highest frequency of samples in the windward slope is related to sands with a size of 250 to 500 microns by 54.68% and in the leeward slope with a size of 125 to 250 microns by 51.97%. Also, the variables of mean diameter, skewness and sorting in the range of 0-2 meters of windward and leeward wind have a significant difference at the level of 95% and no significant difference was observed between the two slops in the Kurtosis variable. Also, it was found that in the range of 2-4 m of Barkhan hills, there is no significant difference between the variables of sorting and Kurtosis on both slopes of the windward and leeward. In this range, a significant difference was observed between the two variables of mean diameter and skewness at the level of 5%. The results show that the ratio of homogeneity of sand grain dimensions in the windward and leeward is different.

Wetlands ecosystem is regarded as one of nature and tourism aspects. These ecosystems are of special ecological properties and unique biodiversity due to specific climate and ground conditions. Gandoman wetland is one of important wetlands and rich ecosystems in Chahar-mahal and Bakhtiari. Not considering the wetland environmental conditions has caused some problems and challenges. One of problems can be mentioned as entering the agricultural wastewater into the wetland leading to the heavy metal contamination. Sediments are important as the most basic absorbent of contaminants. Thus, the current study has been conducted to measure such heavy metals as lead, cadmium, copper and zinc within sediments of wetland entrance and exit. 24 sediment samples have been taken from the entrance of Gavkosh and Ghale-Armani and exit of Ashkoft-Zoleikha in summer and fall in 2018. After specifying the amounts of elements in the sediments, in order to determine the contamination intensity, Muller Geoaccumulation Index was used and National Oceanic and Atmospheric Administration (NOAA), Interim Sediment Quality Guidelines (ISQGs) and Ontario Ministry of Environment Screening Level Guidelines (Canada environment standard) were applied to assess the limit of element contamination. Results of Muller Geoaccumulation Index indicated that the wetland sediments are in the moderate-high range of Cadmium but lead, copper and zinc are in the non-contaminated level. Results of sediment elements’ mean comparisons indicated two indices of ISQGs and Canada environment standard showed the amount of Cadmium higher than the specified limit but other elements are not contaminated. Results of t-test confirmed the results of sediment quality standards indices.

Biodiversity is one of the important concepts in ecology and vegetation management, and plays an important role in the health, production, and evaluation of ecosystems. Species diversity is a major part of biodiversity and one of the most important parameters of ecosystem changes. In this research, the data of the rangeland evaluation different climate zones of Isfahan province were used in five range sites of Alavijeh, Charmshahr, Khondab, Kalahroud and Mouteh to study the variations of the diversity and richness of species with production in the steppe rangelands. The sampling was done on random -systematic and the density and percent of vegetation conopy of each species along the transects using constant plots and production are also estimated by double measurement using the coating. The diversity numerical indices were calculated using Excel, PAST, Ecological Methodology and PRIMER softwares. In order to investigate the relationship and presentation of the model between species diversity indices with parameters (production, density, and canopy cover percentage) from pearson correlation analysis and multivariate regression analysis were used in spss software. The results from the correlation analysis mirror the significant correlation between some species diversity indices and vegetation parameters. The results from the correlation analysis show mirror the significant correlation between some species diversity indices and plant cover parameters. The correlation coefficient of different indices of biodiversity in different regions with density of 0.76 to 0.98, vegetation percentage is 0.74 to 0.92 and production is 0.71 to 0.92. Also, the results from the multivariate regression analysis reflect the effect of the density, vegetation of herbaceous broadleaf (%), and total Coverage on the production. In the rangelands under study, Menhinickchr('39')s richness index was able to justify 13.1% of the changes of herbaceous broadleaf productions. Among the species diversity indices, Hill’s index N2, Simpson index, and McIntosh index and among the evenness indices, Camargochr('39')s index and Shannon-Wiener’s index had the most connection with production and they can justify its changes.

In the 3 last decades, there were efforts to consider the economic value of ecosystems in the framework of virtual markets, in order to have a better recognition and protection toward them. Therefore, the authors of current study tried to use conditional valuation and mutual 2-dimensional technique, since they have a good knowledge about the valuable services of forest ecosystem of Sheikh mousa in Babol city. 157 questionnaires were distributed among the population (eastern banpey region in Babol) in 2017-2018 period. The factors effective on propensity to pay to stakeholders based on Protective valuation scheme had been investigated. In addition, sampling was performed according to Michel & Carson’s method. The current study is quantitative and results were analyzed in maple 18, shazam 11 & excel 2016 software. The consistency and reliability of information resulted from logit pattern showed that proposed price, age, not being the head of family, visiting the area and environmental ethics are the main effective factors on the propensity to payment for protecting the forest ecosystem of sheikh mousa region. In addition, the annual propensity toward individual payment is equal to 7892.92 Rials (1.87 dollars), and the overall protective value of mentioned ecosystem is more than 2276 million Rials (66096 dollars). In addition, the minimum voluntary investment (available capital) to protect the forest ecosystem of sheikh mousa, from the preference perspective of stakeholders of related society is around 1289 million Rials. According to the obtained results, it can be argued that protecting from this forest ecosystem because of its valuable services from stakeholders perspective is very important. Therefore it is suggested that by establishment of NGO and workshops in the city by corresponding authorities, the environmental ethics and tendencies of people toward protection of such ecosystem get changed. In addition, performing more studies about other applications and services of these type of ecosystems is proposed, in order to have a higher and better understanding in public community and responsible managers about these ecosystems.

Attention to rangeland ecosystems is important because rangeland ecosystems have significant impacts on human agriculture and food security and also have various functions that would not be possible for humans to live without. Therefore, the purpose of the present study is to estimate the conservation value and investigate the contribution and ranking of selected Sheikh Moussa rangeland ecosystem services through people's preferences in the form of Choice Modeling (CE). For the next study, the most important Sheikh Moussa rangeland services, including biodiversity, medicinal plants, ecotourism and artefacts, have been identified through field survey and ecosystem services separation. In order to investigate the preferences of the individuals, 170 questionnaires were distributed among the population of the Eastern Bandipur district in the 2017. The results of the present study showed that individuals' annual Willingness To Pay (WTP) to improve the status of the desired ecosystem services amounted to 66692.29 Rials ($ 2.55) and the total value of services rendered was 2667 million Rials ($ 8219.09). The results show that the variables of income, being the head of household and visiting the area are the most important factors affecting the willingness to pay. Based on the values obtained, the priority of the people of the region is to focus more on biodiversity services. Also, the value obtained by the selection test method was able to provide the contribution of each function according to Lancaster's theory. Consequently, ..

Industries like steel, along with wealth generation and economic development, create many environmental problems, such as air, water, and soil pollution and waste generation. Since environmental protection is considered one of the pillars of sustainable development, solutions should be adopted that minimize environmental hazards, and promote the existing industry towards sustainable development. . The purpose of this research is to evaluate and manage the environmental risk of Ardakan Steel and Melting Company using the EFMEA method.

Firstly, with the field visit of Ardakan Steel and Melting Company, were identified all hazards and environmental aspects and calculated using EFMEA method. Then, the data were analyzed using SPSS software. Regarding corrective actions, a secondary evaluation was performed. Finally, the mean of initial RPN and secondary RPN were analyzed and compared by t-test.

In this study, 316 environmental risk factors were identified, of which 39 were at low risk, 139 were at medium level and 138 were high risk. Also, the comparison of the means from the two evaluations showed that the average of initial data decreased from 1466.45 to 1248.16 in the secondary data.

The results of this study showed that by choosing the right method and planning and providing preventive and corrective strategies, the environmental hazards of the industries could be significantly reduced.

Assessing and monitoring rangelands in arid regions are important and essential tasks in order to manage the desired regions. Nowadays, satellite images are used as an approximately economical and fast way to study the vegetation in a variety of scales. This research aims to estimate the coverage percent using the digital data given by ETM+ Landsat satellite. In late May and early June 2018, the vegetation was measured in Ardakan plain, Yazd province, Iran. Information was obtained by 320 plots in 40 transects and also, the satellite images in terms of sampling time were downloaded and processed in USGS website. 16 indices involving NDVI, NIR, MSI, SS, IR1, MIRV1, NVI, TVI, RAI, SAVI, LWC, PD322, PD321, PD312, PD311 and IR2 were estimated. Through estimating the indices and extracting the values in order to conduct index-based predictions, six data mining models of Artificial Neural Network (ANN), the K Nearest Neighbor (KNN), Gaussian Process (GP), Linear Regression (LR), Support Vector Machine (SVM) and Decision Tree (DT M5) have been applied. Model assessment results indicated high vegetation estimate efficiency based on the indices but the model KNN with Root Mean Square Error (RMSE= 2.520) and Coefficient of determination (R2= 0.94) and (RMSE= 2.872 and R2= 0.96) had the highest accuracy in the training and data sets, respectively. As well, to determine the weight and importance of parameters, and to estimate the coverage percent, the weighing process were conducted based on support vector machine. Weighing results indicated that the KNN model and the Simple Subtraction (SS) index had higher weight and importance in terms of vegetation percent.

Rangelands are natural ecosystems having large genetic resources. Since plant vegetation is the bed of life on earth and changes under the influence of surrounding environmental elements, using environmental element can highly contribute to estimate vegetation percent more accurately. Two effective elements which can contribute to estimate the vegetation distribution are climatic elements and geomorphometric. Nowadays, one of new techniques which have attracted much attention to estimate vegetation percent is machine learning process which is able to establish a relationship between various variables of environmental conditions with the least costs and workforce. Therefore, in this study, geomorphometric and climatic elements and data mining techniques have been applied to address the vegetation percent.

The studied region is a part of Yazd-Ardakan plain and Nadoshan region. Sampling and measuring vegetation percent have been carried out in using transects and plots. In order to extract the geomorphometric elements, digital elevation models and SAGA software were utilized and also, seven meteorological stations were regarded to achieve the climatic elements. In the current research, to investigate the impact of different climatic and geomorphometric elements on vegetation percent estimate, data mining models such as artificial neural network, the nearest neighbor, support vector machine, decision tree, Gaussian process and linear regression were used.
Artificial neural network: is one of computational models which can determine the relationships between inputs and outputs of one physical system and a network of connected nodes even if they are complicated and nonlinear.
The nearest neighbor: involves selecting a certain number of data vectors and random sampling from the set-in order to simulate the time interval followed by a certain period.
Support vector machine: is an efficient learning system based on theory of optimization applying the inductive principle of structural error minimization which leads to a total optimum response.
Decision tree: is a method to estimate the discrete functions which are strong against the confused data and are capable to learn the terminology with two different fields.
Gaussian process: is a random one consisted of random values in each point in a time or location domain so that each random variable has a normal distribution.
Linear regression: is applied to model the value of a dependent quantitative variable based on a linear relationship with one or more independent variables.
To assess the models and compare the results, such assessment criteria as RMSE, correlation coefficient and coefficient of determination have been used. Here, to weigh the input parameters of support vector machine algorithm, normal vector coefficients related to a linear support vector machine were specified as the weights.

The study indicated that data mining models are able to estimate vegetation percent more accurately. Using geomorphometric elements, data mining models have shown that Gaussian process model had the most accuracy in the set of training and test data. As well, in applying the models on climatic data, it has been reported that decision tree had the most accuracy in the set of training and test data to estimate the vegetation percent.
 

Vegetation is controlled by such environmental variables as geomorphometry and climate. The results have indicated that geomorphometric elements are of more impact on vegetation percent prediction as compared to climatic ones. Weighing results showed that such geomorphometric elements as distance to waterway, waterway baseline and elevation and such climatic ones as humidity affecting the vegetation growth rate were of the highest weigh and impact in vegetation percent prediction in the desired region.

Concerns about the inadequacy of environmental quality exist in most cities of Iran. Environmental problems represent one of the most important issues in modern urban areas, alongside their conflicts with the natural environment. The urban environment comprises the three sub-systems of natural environment, socio-economic environment, and human structure. Moreover, quality of life in cities is one of the main elements in urban development. As a consequence, Urban Environment Quality Assessment has been of great importance in urban development planning. Generally, quality of life is an important criterion for meeting the needs of urban citizens and for enabling social and economic services for them as well as ensuring access to such urban amenities as hospitals, parks, etc. This research study aimed to identify and rank the environmental indicators in Kermanshah city though use of a questionnaire, the Delphi technique and factor analysis. This research was descriptive-analytical in terms of its character and objectives, and fro the perspective of data and information collection in a documentary and survey manner. The statistical population of the study comprised environmental experts identifies according to their environmental conditions and the indicators were extracted using the Delphi technique, as a knowledge-gathering method, and questionnaires. The members of the Delphi panel comprised between 10-15 people distributed over two or three rounds based on the agreement of the members of the questionnaire group. With the consent of the members of the Delphi panel, three rounds of questionnaires were distributed and, in each round, some of the indices were eliminated from the total of the questions and the factors that scored highest in each round were selected for the next one. In order to evaluate and analyse the questionnaire data and determine the main factors, a factor analysis method was used in SPSS software. Factor analysis is a method for reducing a large number of quantitative variables into a small number of underlying assumed variables, known as agents, and its main purpose is to reduce the volume of data and to determine the most important variables in the formation of a particular phenomenon. According to the results of the analysis of questionnaires in three rounds of 51 primary indicators extracted from internationally accredited institutions and indices of Iran, and the localization of these indicators for Kermanshah, 15 indicators were selected as final indicators. After analysing the data using the factor analysis method in SPSS software, the results showed that among the 15 final factors, the six following factors relating to air pollution monitoring station density, wastewater treatment, natural disasters, ratio of durable buildings to total buildings, the volume of produced waste, and the density of green spaces were of a high magnitude of one and were selected as the main factors that gave a total of 82.336 variance among the community. The factor of air pollution monitoring station density was allocated as the first factor with the highest variance at 31.046. Thus, it can be concluded that the determination of indicators for assessing the quality of urban environmental conditions is considered as the most important and is the first step in determining the quality of any given urban environment. In addition to studying and studying the urban environment of Kermanshah, this research provides an appropriate basis for developing strategies for urban sustainability with environmental attitudes in order for environmental conditions of Kermanshah to evolve. Of the six final factors, there are four physical-chemical factors that indicate the high sensitivity of this environment and the need for high level officials to increase the quality of this urban environment.

Geomorphological map is one of the main information layers in natural resources studies. So far, various methods have been proposed for the classification and separation of various units and Geomorphological types, most of which are based on qualitative and descriptive information. In this study, the ability of geomorphometry parameters in separation of mountains from pediment and also separation of different types of pediments was investigated. First, ground truth map was prepared using visual interpretation of satellite data and topographic maps. Then the 1000-point sampling grid was designed randomly. Parameters including profile curvature, plan curvature, tangential curvature, cross-sectional curvature, longitudinal curvature, and general curvature were prepared from digital elevation model in the GIS software. Then, their values were extracted at all points of the sampling network. Then, artificial neural network with structure of 13_6_ 4 was used to separate the units. The results showed that the erosion pediment could be separated from epandage using artificial neural network; however, the separation of epandage pediment from covered pediment was not well. For this purpose, to improve network performance, the digital value of Landsat 7 data was added to the previous values. The resolution accuracy of mountain, erosion pediment, epandage pediment, and covered pediment was calculated to be 90, 79, 80, and 76%, respectively.

Rangeland ecosystems provide a wide range of services such as gas regulation function whose economic value has not been understood. The present study aimed to estimate the economic value of CO2 absorption and oxygen generation services using unit price in Sheikh Musa Rangeland, Mazandaran Province, Iran. In the study area, clipping and weight and photosynthesis methods were applied to estimate dry matter production, CO2 absorption, and oxygen production. Also, Shadow price, Replacement cost, and Social cost methods priced the economic value of gas regulation function differently. Finally, their means were compared and their geometric mean was used as the unit price; then, the economic value of the function was estimated in 2016. Results showed that Sheikh Musa Rangeland ecosystem annually produces 2081.4 t dry matters and 2454 t oxygen and absorbs 7294.15 t CO2. Given the estimated price, the value of CO2 absorption function was found to be 7264.6 million IRR and the economic value of oxygen production was calculated as 3,852 million IRR per year. In overall, the economic value of Sheikh Musa ecosystem was estimated as 11117.4 million IRR (318364 US $) per year and 1.06 million IRR per ha. Given the valuation that shows the minimum value of Sheikh Musa ecosystem and high importance of its gas regulation function, it is recommended to conduct further studies on pricing models for Rangeland ecosystems and to apply environmental management practices for the sake of Rangeland and local health.

Native plant development is one of the ways to restore degraded rangelands. In Dezful, Anchusa strigosa is a medication species which is one of the region’s main exports. Due to habitat degradation of this species by overgrazing and rangeland degradation, by considering ecological demands, its habitat can be developed. The aim of this study was to determine the potential sites for development, according to the criteria of Anchusa strigosa climate, soil and topography using geographic information systems and hierarchical analysis. For this purpose, In 2015, the spatial data for species presence was used as potential locations for growth. Part of the habitat of this species was extracted from studies using ground and the points which were grabbed. The first point map of the field was prepared by visiting the areas and habitats, and then current biophysical information was extracted. For completing the information, from other sources, the ecological demand of species was extracted and combined with ground-based data. The six criteria map were prepared, classified and standardized in ArcGIS®10.1. As the weight of the layers is not identical, to prioritize the areas of potential habitat, analytical hierarchy process (AHP) was used to weight the criteria. The results showed that of total area 464547.3 ha, 31% accounts for good habitat, 38%, average habitat and 7% poor to very poor habitat. The results also showed that the significant dip weight and the minimum weight is most significant measure that shows no inclination and most valuable to the growth of this species. The results can be used to modify the operation of the ranch and mapping of suitable areas for development use.

Known of ecosystem of range details and relation bet ween this details including soil and vegetation, is Necessary for optimum management of ranges. To determine the effect of some soil properties on species distribution of Dorema ammoniacum and Rheum ribes in ranges of Baghedar region, Information of vegetation were harvested with systematic-random method in the form of 40 plots and during 4 transects. After drilling soil profiles in beginning and end of each transect and samples of 0-10 and 110-80 cm, the parameters pH, EC, CaCo3, organic carbon, CaSo4, Co3, Hco3, Cl, So4, Ca, Mg, Na, Fe, Cu and soil classification grain distribution was determined in the laboratory. After Collection of data for Analysis, it was used Principal components analysis method. The results of analysis between soil variables and vegetation show that soil texture, CaCo3, EC, OC, CA, Mg, Cl and Na had more impact on distribution of vegetation types and Dorema ammoniacum and Rheum ribes.

In order to optimum management of ecosystem of range, need details and relation between this details including soil and vegetation known. To determine the effect of some soil properties on species distribution of Eryngium bungei in Baghedar summer Bafgh region, Information of three types of vegetative plants were identified Artemisia aucheri - Eurotia ceratoides, Artemisia aucheri - Eryngium bungei and Artemisia aAucheri - Stipa barbata in the form of 20 plots were harvested for each type in the desert. After drilling 27 soil profiles and samples of 0-30 and 30-60 cm, the parameters pH, EC, CaCo3, organic carbon, CaSo4, gravel and soil classification grain distribution was determined in the laboratory. Analysis of variance showed that clay and CaCo3 in the soil first depth and CaCo3 in the soil second depth in three vegetation types with significant differences are. Principal components analysis on 16 soil variables and percent slope showed that the first principal component included percent slope, clay in the second depth and CaCo3 and sand in the first depth, explain 61% of the variations and the second components included sand in the second depth and electrical conductivity and organic matter in the first depth, explain 38% of the variations. The results show that Eryngium bungei be seen on soil with more clay in lower layer and more CaCo3 and less organic carbon and EC in upper soil layers.

This research was conducted to investigate the relationships between soil (organic matter, potassium, phosphorous, sodium, fine gravel, soil texture, EC, lime, gypsum, nitrogen) and environmental (elevation, slope) factors with distribution of vegetation types in rangelands of Sabzdasht, located in Bafgh, Yazd province at 2012. For this purpose, four vegetation types were selected as follows: Artemisia sieberi; Artemisia sieberi, Stipa barbata, Eurotia ceratoides; Dorema ammoniacum, Artemisia sieberi, Eurotia ceratoides; and Hammada salicornica. Minimal area was determined using nested plots. Afterward, vegetation factors were measured and five soil profiles were dug randomly in minimal area. In each profile, data for depths of 0-10 and 10-80 cm were recorded. Principal component analysis was applied to analyze the data. Results showed that soil texture, potassium, phosphorous, EC and lime had the most impact on variation and distribution of vegetation types.