حمیدرضا عباسی

The phenomenon of dust storms has become a global environmental challenge. As a natural disaster, it has significantly affected Khuzestan province due to its geographical location and proximity to vast desert areas. This study aims to examine land management strategies to mitigate dust production in the southeastern dust source of Ahvaz by implementing effective land management techniques to control wind erosion in this region.

To conduct this research, ecological land resources—including climate, geology, soil properties, land use, vegetation cover, wind erosion, and agricultural and livestock conditions were analyzed using satellite imagery and extensive field surveys. By overlaying maps, the dust source area was classified into ecologically homogeneous units (work units). Based on the physical and chemical properties of the soil, the vegetative potential for biological stabilization was determined according to the ecological requirements of native plant species. Soil samples were collected from 106 points at three depths, and soil erodibility was assessed using a wind tunnel. A wind erosion sensitivity map was then generated to prioritize the stabilization of work units. The characteristics of erosive winds were analyzed using hourly wind speed and direction data from 21 meteorological stations. After creating a database of ecological resources in a GIS environment, the vegetative potential of the work units was evaluated using soil properties. Subsequently, specific stabilization projects were proposed for each work unit.

The findings of this study indicate that the stabilization strategy was planned systematically, considering the ecosystem type, and dust control projects were designed based on land use classifications. The land use distribution of the dust source area includes 37% rangelands, 10% bare lands, 11% dried wetlands, 24% rainfed agriculture, and 13% irrigated agriculture. The proposed projects included biological measures such as shrub planting, afforestation, roadside tree planting, and living windbreaks along farm edges, as well as management strategies such as soil moistening, leaching, irrigation, grazing control, construction of non-living windbreaks, and rainwater harvesting techniques. Analysis of the energy trend of erosive winds over the past decade revealed no significant changes. Instead, the activation of dust sources was attributed to land use changes, precipitation patterns, and drought occurrences.

The lack of water allocation to downstream ecosystems, combined with the construction of large dams and multiple watershed management structures in upstream areas, has led to the transformation of wetlands and sedimentary plains into major dust sources and has contributed to surface soil salinization. Restoring flood capacity in these areas was achieved through the construction of water supply channels to meet the water demands of biological stabilization projects and facilitate the moistening of wind erosion-sensitive units. Overall, the implementation of these projects demonstrated that this ecosystem restoration-based approach, with a focus on wind erosion-prone lands, can serve as an effective model for stabilizing the country’s dust source areas.

Salinity, caused by the accumulation of water-soluble salts in soil, is a major limiting factor for plant growth and development. A significant portion of Iran's soils are saline, which can severely restrict the cultivation of various poplar species. Therefore, determining the salinity tolerance of different poplar species can provide valuable guidance for poplar plantations in saline areas. This study investigates the morphological, physiological, and biochemical responses of Populus nigra L. clone “62/154” to varying levels of salinity stress. This high-yielding clone is widely used in poplar plantations across Iran. A pot study was conducted under controlled conditions using a completely randomized design to assess the morphological, physiological, and biochemical responses of this poplar clone to different salinity stress levels (0, 50, 100, 150, and 200 mM). Poplar cuttings were collected from the Alborz Research Center in Karaj, Iran, and planted in pots filled with clay-loam soil. The pots were placed outdoors during the experiment. The cuttings were initially irrigated with fresh water for three months before saline water (NaCl) was applied. After six weeks of salinity treatment, we measured survival rates, growth parameters, biomass production, relative water content (RWC) of leaves, macro- and micronutrient concentrations in plant tissues (leaf, stem, and root), and several physiological parameters (proline and sugar contents, malondialdehyde concentration, and enzyme activities). Data were analyzed using one-way analysis of variance to identify significant differences due to salinity treatment, with means separated by Tukey’s HSD test. The results indicated that poplar plants subjected to low salt stress (50 mM NaCl) exhibited no significant differences compared to control plants regarding survival, growth, biomass production, or physiological and biochemical parameters. However, at higher NaCl levels (100, 150, and 200 mM), soil salinity significantly reduced survival rates, growth parameters, biomass production, leaf RWC, and concentrations of nitrogen (N) and potassium (K) in plant tissues. Additionally, calcium (Ca) concentrations in roots and leaves decreased alongside magnesium (Mg) levels in leaves. Conversely, higher salinity increased leaf physiological parameters (proline and soluble sugar content), activity of antioxidant enzymes (CAT and POD), malondialdehyde concentration, as well as sodium (Na) and chloride (Cl) concentrations in plant tissues. Notably, phosphorus (P), iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) concentrations in roots and leaves also increased compared to control and 50 mM NaCl treatments. The most pronounced changes occurred at 150 and 200 mM NaCl. Overall, high salt levels (150 and 200 mM) led to a marked decrease in survival rates, growth, and biomass production along with significant morphophysiological and biochemical changes in the poplar plants. After six weeks of exposure to these salinity levels, survival rates dropped by nearly half. The observed decreases in survival rates, growth parameters, biomass production, changes in physiological parameters, nutrient absorption and accumulation in plant tissues—as well as higher accumulation of proline and sodium/chlorine elements—indicate that P. nigra clone 62/154 is salt-sensitive. Therefore, it is crucial to consider soil salinity levels and the sensitivity of this poplar clone when planning poplar plantation programs. Keywords: Black poplar, growth parameter, nutrients, proline, soil salinity.

Recognized as the hosts of a wide variety of formative processes, deserts represent vital ecosystems within Iran's natural landscape. On the other hand, wind erosion exerts particularly significant influence on such arid regions, playing a key role in shaping the environment while posing serious environmental risks. Moreover, wind-driven movement of active and semi-active sand dunes decreases the comfort levels for local inhabitants, putting agricultural lands, settlements, and transportation routes at risks. Consequently, studying the dynamic behavior and variability of wind-driven sediments, especially in arid and desert regions, is of great importance. While UAVs (Unmanned Aerial Vehicles) may not fully replace traditional methods of spatial data collection, their unique capabilities allow them to be integral to the map-making process, offering more economical alternatives. Analyzing statistical summaries within the study timeframe facilitates an understanding of the spatial and temporal patterns of the sand dunes. As with many natural phenomena, wind erosion and sand dune dynamics can be complex and elusive; therefore, the investigation of their various impacts requires the application of contemporary methods such as statistical analysis. In this regard, this study mainly sought to develop a conceptual framework that outlines the patterns of sand features in the study area and elaborates on their interrelationships.

This study was conducted in an area covering approximately 200 hectares of sand dunes in the southern region of Mezinan Kalate, located in western Sabzevar city. The area features various sand formations, including Nebkha and Barkhan. To analyze the spatial patterns of the complications observed, the exact locations of such complications were identified, followed by an assessment of their distribution patterns. The paired univariate function (g(r)) was then employed to investigate the distribution patterns of different complications and their impacts on similar types. Additionally, the bivariate pairwise correlation function (g12(r)) was utilized to explore the interactions among various complications in the study area. Initially, a general assessment of the region was conducted through a field visit, followed by aerial photography using a drone to collect the required data regarding the complications from the study area. After analyzing the images, an orthophoto was generated. Then, a point map was created for spatial locations via ArcGIS 10.2, detailing the distribution of sand dunes and vegetation within the study area. Furthermore, the Kolmogorov-Smirnov test was applied to evaluate the normality of the statistical data. Finally, data processing and spatial analysis were carried out using the Programita software, which involved univariate and bivariate correlation functions, along with O-ring functions. The software employed a Monte Carlo simulation with 199 repetitions, achieving a 95% confidence level and a 5% significance level for the random distribution of the two species investigated.

The diagram illustrating the distribution pattern of sand dunes employs the O-ring function, utilizing the g(r) function values to analyze the spatial arrangement of the dunes. Findings from the application of this univariate function indicated that Barkhans did not display a significant spatial pattern. The finding is supported by the O(r) function, reaffirming that the spatial arrangement of Barkhans lacks any significance. The results of the g(r) function in examining the spatial pattern of Nebkhas via univariate functions revealed that within distances ranging from zero to 270 meters, the spatial pattern of the species was characterized by cumulative or clustered shape, and that no significant pattern was detected beyond 270 meters. Similarly, the results of O(r) function suggested that the spatial arrangement of Nebkhas formed clusters within the 0 to 270 meters range, with no significant pattern being observed beyond 250 meters. Additionally, the results obtained from the bivariate function g12(r) showed a negative correlation between these two elements up to about 500 meters, demonstrating their opposing influences on each other's formation and distribution. This finding is consistent with the distribution map of the two elements. The bivariate function O12(r) was also used to validate the results found in g12(r), yielding consistent outcomes with those derived from the pairwise correlation analysis.

The findings obtained from the spatial analysis of sand dunes and Nebkha indicated that the distribution of sand dunes in this area was intricate, while the arrangement of Nebkhas remained inconsistent. Together, these factors adversely impacted the formation and development of both phenomena. This situation may arise from the phenomena’s similar requirements for the establishment, specifically the availability of sand. It may also be driven by the presence of certain favorable environmental conditions.

Dust is one of the environmental issues that affect air quality and pollution, human health, soil fertility, and many social and environmental aspects of society. Wind erosion and sand dune movement have adverse environmental consequences. Identifying factors affecting sand mobility and predicting their condition in the future is necessary to control the wind erosion process. The purpose of this study is to identify and monitor the sources of dust and quicksand in the Jolfa, ShushQom and Gildir areas.

Analyzing wind climate data, identifying the sources of fine dust production, measuring and monitoring the production of dust and wind deposits were done using the RDD index. Also, the threshold speed and intensity of wind erosion were measured using a wind tunnel device. In order to investigate the effect of climate change, especially wind and rain, on the activity of sands and to predict the possibility of movement of sand dunes and sand dunes and the dust caused by them, Lancaster's global method was used.

The results of the Lancaster index showed that 10% of the statistical years were in an active state, which corresponded to the years 1996, 2000 and 2001. Whereas, the immobility of sand dunes (inactive) according to the Lancaster index has accounted for about 26% of the statistical years; 65% of the time in 2020, sand dunes were in an active or sand-moving state at the top of the dunes. The lands of the Jolfa micropollution center are mainly formed by the type of gravelly and sloping fan-shaped debris, and the soils of ShushQom and Gildir micropollution center are mainly a combination of mountains, hilly plains and flood plains. The results of wind tunnel tests on soil samples collected from the land surface of the Jolfa region showed that the erosion threshold of the collected sample is 8 m s-1.

According to the results of this research, abandoned rain fields, poor pastures, dry river beds and seasonal stream, etc., in the presence of environmental factors and accompanied by adverse climatic factors, are potential sources of dust and fine dust production, but the said lands in East Azarbaijan province are scattered and in certain conditions and times, they can produce a significant amount of fine dust.

The implementation of the forest restoration plan in the northern region of Iran has led to an increase in efforts to enhance wood production through the cultivation of poplar seedling. Particularly, poplar trees hold a significant position among wood producers due to their distinctive features. The key consideration revolves around identifying suitable and cost-effective lands for planting fast-growing species. Purpose of this study focuses on assessing the land suitability for poplar (Populus nigra L.), a prevalent forest species in the country, through a quantitative land evaluation method based on the FAO approach.
The research gathered and classified the edaphic and climatic requirements of poplar tree by utilizing various library resources, data from the soil laboratory of the Research Institute of Forests and Ranglands, and field survey (Soil Profiles). The climatic and soil characteristics were quantitatively classified into five categories: highly suitable (S1), moderately suitable (S2), low/critically suitable (S3), The Quantitative Classification of soil and climate properties was done in five classes: suitable (S1), moderate suitability (S2), low or critical suitability (S3), currently not suitable (N1) and permanent not suitable (N2). For validation, a quantitative assessment of land suitability for poplar cultivation was performed across six soil types, including Nowshahr forest brown, Nowshahr gray brown pedzolic rich in organic matter, Chamestan alluvial regosol, Chamestan Rendezina, Chalous  Pseudogley , and Karaj alluvial cambisol, using a parametric method (second root).
Results indicate that spruce thrives in wet and semi-humid regions in a dry-type manner, with ideal conditions found in areas receiving 1500-1800 mm of rainfall. In drier, semi-arid zones, irrigation is essential for meeting water requirements. Optimal growth temperatures for spruce range from 11-16 degrees Celsius in moderate climates. Poplar flourishes in soils with a light to medium texture, granular or cubic structure, good to fast drainage, and low underground water levels with adequate calcium and magnesium cations.
The study showed that the most suitable soils for poplars have a light to medium texture with a granular or crumb structure, with adequate drainage, the absence of high groundwater and the sufficient amount of calcium and magnesium cations in the soil. Soils with incomplete drainage and heavy texture do not provide suitable conditions for poplar plantations. In terms of quantitative evaluation, Mollic Udifluvents soils with medium texture had the highest score for poplar plantations.

Wind erosion is one of the destructive phenomena that cause environmental changes, changes in the quality of the weather threatens public health, and other economic and social issues in regions with dry and semi-dry climates. Using wind tunnels, the effect of wind velocity and soil properties, as well as the particle transport process, can be investigated under controlled conditions. Ries and Fister estimated the amount of wind erosion in the Ebro basin using a portable wind tunnel in 2009. To evaluate the rate of soil loss, three sample locations were assessed, and the results showed that the areas with unchanged ground surface had the lowest amount of wind erosion. The phenomenon of dust storms in Khuzestan province has had an increasing trend in terms of frequency and continuity in recent years. Considering the issue's importance, the present study was conducted to determine the threshold erosion velocity and erodibility of soils taken from the dust storm centers of Mahshahr, Omidiyeh, and Hendijan, using a wind erosion measurement device.

The dust centers of Mahshahr-Omidiyeh-Hendijan are located between 30°12'28" to 30°50'57" north latitude and 48°47'45" to 49°41'41" east longitude and have expanded between Mahshahr and Omidiyeh and Hendijan. Using the land unit map, maps from the Geological Survey Organization, and field studies, 32 points were identified in the Mahshahr, Omidiyeh, and Hendijan centers, representing various land units differentiated in the soil map. Finally, ten average points were selected. Samples taken from the soil surface inside the wind tunnel were tested. First wind thereshold velocity, Then the wind erosion rate was measured at speeds of 15, 20, 25, and 30 (m/s) for two minutes, and finally, the wind erosion rate of the sample points was obtained. The median diameter and mean diameter of the particles were determined using Gradistat software to determine the erodibility of the sample particles according to the Chepil theory (Table 2).

 the amount of wind erosion increases at wind speeds of 15, 20, 25, and 30 (m/s) over two minutes. Under these conditions, higher wind speeds intensify soil loss and lead to an increase in the rate of wind erosion. The wind erosion threshold varies from 6 to 17 (m/s). The minimum wind threshold velocity is related to the Jarahi-Mahshahr sedimentary plain, which is sensitive to wind erosion at a threshold speed of 6 meters per second and the total amount of wind erosion rate of 12160 (gr/m2.min). The total amount of erosion rate ranged from 360 to 21860 (gr/m2.min) and the highest erosion rate was related to alluviums and alluvial cones in the shape of the Hendijan anticline. the erosion potential of soils taken from dust centers in Khuzestan province is high, and the dominant particle diameter of the soil is 0.5-0.15 (mm) and 0.05-0.1 (mm), which are susceptible to wind erosion. Therefore, all samples collected from dust centers in Khuzestan province are sensitive to wind erosion

   Locating areas sensitive to wind erosion is one of the important solutions for stabilization. Given the importance of the issue, this study has focused on estimating the erosion potential and threshold velocity in the dust centers of Mahshahr, Omidiyeh, and Hendijan. The results of measuring the erosion rate using a wind tunnel device showed that the soil in these areas has a high erosion potential, and the erosion rate increases significantly with increasing wind speed. The minimum of the wind threshold velocity for sedimentary plains in jarahi-Mahshahr region, located in the northwest center, which indicates the high sensitivity of the soil in the area to wind erosion. The highest amount of wind erosion rate was related to alluvial fans and alluvial cone in the shape of the Hendijan anticlin. The fan-shaped alluviums deposited by the temporary rivers at the foot of the anticline mountains east of Hendijan, because the materials transported by the temporary rivers are mostly fine-grained and marls, so the amount of gravel in these alluviums is low and for this reason, the erosion susceptibility of these soils is very high and they should be stabilized in the early stages. These results are consistent with the results of Abbasi, which led to the preparation of a map of land sensitivity to wind erosion in this center. Studies related to particle size distribution showed the high sensitivity of the samples to wind erosion. Since the dominant diameter of all particles in the samples was in the range of 0.5-0.15 and 0.1-0.05 (mm), the potential for erosion susceptibility of all samples in the study area is high. However, in this theory, only one factor has been used to determine the potential for soil erosion and other effective parameters in erosion susceptibility have not been considered, so it is not possible to rely solely on this theory to estimate erosion.

It is essential to understand the characteristics of regional winds in order to prevent the effects of wind degradation, which is a significant factor in the degradation of arid and semi-arid land. The main aim of this study was to determine the status of erosive wind and the sand drift potential and its relationship with dust emission areas. Annual wind roses showed prevailing winds from the west, southwest, and northwest. In addition, the annual storm roses showed that the erosive winds were mainly in the west, southwest, and northwest directions. In winter and spring, a multidirectional wind regime is blowing. According to the calculation of the sand drift potential using the Fryberger & Dean equation, wind erosion drift is categorized into the low-to-moderate class, with the resultant sand drift in the southeast direction. Mean quantitative sand discharge rate was 8.9 Ton.m.Yr-1. Based on overlaying vegetation cover, wind velocity, geomorphology, and sand-sea maps, the area with the most potential dust emission was determined. In most areas, dust emissions coincide with wind erosion hot spots. In addition, the variability of wind direction has caused longitudinal sand dunes (Seif and Silk) to form. Therefore, the abrasion of the ground surface by sand drift on the plains with sparse vegetation covers activates the dust emission process in the study area.

This study was conducted in 2020 with the objective of identifying dust source areas and soil susceptibility to wind erosion in the eastern part of Kerman Province, through the integration of field and remote sensing methods. In total, ten study areas covering 3007 square kilometers were identified based on remote sensing and field surveys during the winter of 2020. The dust-prone areas and the determination of the dust event frequency in the past 20 years were established using the optical depth index derived from MODIS Terra and Aqua satellites. To assess soil erodibility, wind erosion threshold velocity, and wind erosion rates, soil samples (17 in total) were measured in a wind tunnel at three wind speed classes: 15, 20, and 25 meters per second. Electrical conductivity (EC) values of soil samples (22 in total) were determined in the laboratory to create a soil salinity map using the kriging method. The results of the vegetation cover index were extended, and the linear relationship between EC was computed using Google Earth Engine and compared with kriging results, indicating significant salinity in the studied areas (EC>16). The analysis of prevailing wind directions and wind regimes based on data from five meteorological stations in the region demonstrated that the Rigān and Nasratābād stations, with transport potential of 561 and 1199 kg m^-1 s^-1, respectively, were classified as high-energy wind zones. Wind speeds of 40 knots (20.57 m/s) were prevalent in these areas. The assessment of soil erodibility revealed that the southern parts had the lowest wind erosion threshold velocity (between 6 to 8 m/s), classifying them as wind erosion-sensitive zones, with an accumulated wind erosion rate of 60 kg/m^2/year across the three wind speed classes. Based on the findings, the study areas are considered significant internal dust source areas, requiring management actions to control dust emissions.

Crusts are a hard layer on surface soil, that is formed by disaggregation– aggregation process in which particles of soil, air, water, and organic matter are connected to each other and classified into different types including physical, chemical, and biological. Chemical crusts like salt crusts are formed due to intense evaporation on the surface of extremely salty soils. Physical crusts are formed raining or through irrigation of agricultural lands and are divided into three categories including structural, erosional, and sedimentary, depending on the process of their formation. The biological crust which is formed by the function of algae, cyanobacteria, mosses, and lichens, and due to their positive protective roles and restoration ability received much attention so far. However, studies on the effects of non-biological crust and their protective role have been considered less. Various effective factors on crust strength have been investigated but land use has been left out. This research has focused on modeling land use effection crust strength, in dust emission sources in the southeast of Ahvaz.

In the south-eastern of Ahvaz in Khouzestan province, three land uses including agriculture, agroforestry, and barren land were selected. In order to measure the strength of the surface crust in selected land uses, a handheld penetrometer was used and crust strength was measured in random points in 30 points in each land use. To reduce the influence of other environmental conditions, measurements were done scattered on each land use. Then, to obtain the strength in one point, three measured points were averaged, and finally, 90 measured points were obtained for each. The surface soil moisture of land uses was done by taking soil samples and measuring in the laboratory, and then significant differences between land use groups were tested by analysis of variance. Normality and homogeneity of variances were tested by using the Kolmogrove-Sminov and Levene's tests on soil strength data set. Due to the fact that the soil texture is different in studied land uses and also the soil texture is one of the most important factors affecting the strength of crust in the measured points, the soil texture was extracted from the existing maps. In order to investigate the effect of these two independent factors on the crust strength as well as their interaction, General Linear Modeling (GLM) was chosen to exclude the soil texture effect on crust strength variation and model the land use effects.

Results showed that soil surface moisture does not have a significant difference in land use groups. By using the General linear model, crust strength was modeled. In the first stage, the effect of land use and soil texture were investigated as the most important factors affecting the hardness of the crust and the results showed that land use and soil texture as well as their interactions are effective in changing the hardness of the crust at the level of 95 % and 99 %, respectively. These factors have an effect on the variance of crust hardness, but the main source of variance is land use, and this factor alone explains about 78 % of the crust strength variance, and the model explains 96 % of the variance of the dependent variable and the presented model is significant at the level of 99 %. In order to check the existence of a significant difference in crust strength in studied land uses, Helmert's Contrast and Bonferroni tests were used. The result showed that there is a significant difference in the average crust strength of barren lands with agriculture and agroforestry at the 99 % level, and no significant difference is observed between agriculture and agroforestry. Then, in order to investigate the single factor of land use, the soil texture was considered as covariance, and its effect on the hardness of the crust was removed. The results showed that there is a significant difference in the average hardness of barren land use with agriculture and agroforestry at the level of 99 %. The presented model explains 86 % of the variance of the hardness of the ridge, and among the factors with a significant level, 99 % of the hardness of the crust in a barren land with 70 % partial effect has the largest role in explaining the variance. With the change of land use from agroforestry to barren land, the hardness of the soil surface increases by 50 %, and with changing to agricultural land, it decreases by 14 %.

In agricultural and forestry land uses, with the increase in the traffic of people and heavy machinery, the crust is broken and does not return to its original strength. Based on these results, it can be said that in desert areas, vegetation conservation is not the only way to protect soil from wind erosion, but protecting the crust against traffic and breakage can be an efficient solution that has received less attention. Legal confrontation with land use change and land plowing can be a sustainable solution for these areas. It is suggested that with a general assessment of the surface strength of the crust on bare land, easily can be protected against the wind only with management practices.

The purpose of this study is to clarify the necessity of considering buffer area and its role in natural or man-made ecosystems, with specific functions. Evaluating the direct and indirect destructive consequences of human manipulations, such as high-rise construction in buffer areas and its effects on the central core of this type of ecosystem is very essential. The National Botanical Garden of Iran has other functions such as preserving Iran's important and endemic species and is a source of their reproduction. In addition, as one of the respiratory lungs of Tehran, it plays a key role in air conditioning and educational programs. Based on this, the signs of urban development on different parts of the environment of this garden including water, soil, air, vegetation and wildlife have been investigated in this article. Based on the available information and the results of field survay, the long-term effects of this type of development on the NBGI have had an irreversible effect on the hydrological changes of the underground water resources, and in the future, the survival and sustainability of the NBGI will be affected due to the lack of underground water supply. In addition, reducing the wind and preventing the necessary ventilation and the formation of thermal islands will cause an outbreak of pests and important diseases on plants. Also, the limitation of soil permeability and the damage to aesthetic values of the garden are other negative consequences of this excessive development, which will threaten the sustainable life of the NBGI.

The purpose of this study is to identify the shape of ruggedness, activity, physical-chemical and mineralogical characteristics of sands in Kermanshah province. The results showed that the most important form in the desert lands of the study area is the sand arrow and the degree of activity of the sand dunes is semi-active and most of them are unstable.

This study provides an applied method to estimate the land sensitivity of wind erosion in the Hamoun-e Baringak Sistan, as an ephemeral lake. Due to the wide extent of the sources of dust and sand production in Sistan, finding areas that are prone to wind erosion is of paramount importance in prioritizing stabilization. For this purpose, indices of transport rate (erodibility), soil shear strength, and SAVI were conducted.  To investigate the land erodibility to aeolian transport, 74 graduated pins were embedded randomly in the ephemeral Baringak Lake bed and the aeolian transport rates were measured for the total study period. The shear strength of the soil surface was measured using Torvane. The vegetation canopy density was extracted from digital images using the SAVI index. The results showed that there is a very significant relationship (1%) between soil shear strength and SAVI indices with transport rates. It means that this proposed method may be also applied to estimate land sensitivity in environments instead of threshold friction velocity of wind erosion in the field. Comparison of the results of regression model estimation with transport rates in the field were significant.

Water scarcity and wind erosion are always the two main challenges of Sistan Plain in Eastern Iran. For more than half a century, research and sand fixation programs have been done to stabilize the soil and control sand dunes in this area, but the challenge of dust and sand transport still causes many economic and social problems. Calculation of erosive wind energy based on sand drift potential (DP) using Fryberger and Dean method showed that erosive winds have very high energy environment (DP = 2513 v.u) at Zabol and Zahak climatological stations. Whereas the relationship between wind power and vegetation follows the hysteresis model, the maintenance of sediments by vegetation at high wind energies is not possible or it is difficult. In fact, vegetation can hold sand up to a wind power threshold. Accordingly, the success of stabilizing sediments is not possible into the four erosive corridors (Gorgori-Puzzak, Niyatak, Jazinak and Tasoki-Rig Chah), and no cost should be incurred in this regard. In addition, urbanization and development of infrastructure into corridors should not be done or should be removed. The stabilization approach in the Sistan plain should be centralized on land sensitive area in the Hamoun ephemeral lakes.

In the present study, the phenomenon of dust and the annual and seasonal trends were studied in Golestan province over a period of 18 years (2000-2017). According to the tools and techniques of Remote Sensing and wind dust diagrams, the dust phenomenon was studied. In order to investigate the occurrence of dust, AOD related to MODIS sensor was used. The results show that the highest annual average of AOD (equivalent to 0.321) was indicated in the year 2009 which shows the highest intensity and concentration of dust. Also, in terms of seasonal changes, autumn and winter seasons have a small share of dust concentration. The highest dust concentration in Golestan province is related to summer and especially July. Also, the seasonal wind dust diagrams show that the dust direction is mostly from west and southwest and the role of north winds in dust production is negligible. This result shows that contrary to popular belief that the source of foreign dust in the province is often Turkmenistan, the role of Turkmenistan in the Golestan dust production is small and the dust mass has entered to Iran from the west and from the northern parts of the country to Golestan province.

Recently, Khuzestan province has been faced by dust storms with a higher mass concentrations and longer durations. Providing the water needed to irrigate the seedlings is one of the basic needs. The potential for runoff production at dust sources has been evaluated in the present paper. For this purpose, the volume and depth of runoff were determined based on the area's hydrologic soil group, vegetation cover and land use layers using the US Soil Conservation Organization (SCS-CN) method at the unit level of the studied areas.The results showed that most of the dust centers with an area of 643300 hectares are covered by barren lands with low vegetation and an area of 522,300 hectares is also included in the hydrological soil group C and D. The calculations derived from the amount of runoff generated in the dust center showed that in South East Dust Center of Ahvaz in the November to January quarter per hectare respectively 80, 120 and 95 cubic meters of water can be extracted. It is possible to produce runoff in the Omidieh-Hindijan dust center in December and January from about 60 to a maximum of 160 cubic meters per hectare, in Hoor Al-Azim-Khorramshahr dust center from 30 to about 80 cubic meters per hectare in the second half of the year and in the place of planting projects that the necessary arrangements must be made to manage the use of this possibility).

Sand dune seas and dune fields or ergs are the results of the wind erosion process in the sedimentation phase, although they are also observed in the transport area. It is crucial to prepare a map of wind sediment dispersion in the country from the point of view of wind erosion, the challenge of fine dust, and the damages caused by their movement. So far, various statistics have been presented on the area of windy sand unevenness of the country. To study the distribution and other features of the country's sandstones, as well as to prepare spatial databases using digital images (Landsat, IRS, and Google Earth database), aerial photographs (1993-2003), and field operations, a new map of their distribution in 20 provinces of the country was determined. The results showed that the area of sand fields in the country is about 4.7 million hectares, which is the highest in Kerman province (1224512 hectares) and the lowest in Tehran province (73 hectares). Yalan or Lut with 1458320, Jazmourian with 566326 and Jan with 477880 hectares are the three largest sand dunes in the country, respectively. There are differences in the area of sands in the country.

Iranchr('39')s location on the arid world belt, the occurrence of climate change and global warming and the increased in human interference have resulted in dust storms phenomenon in the western and southwestern parts of the country, especially in Khuzestan province. The present study has been aimed at investigating the existing water resources of the province for the watering operation of the southeastern dust source of Ahvaz with the first priority for providing A quick solution. Since this site is located within the catchment area of the river of Koopal, to study the discharge rate and its runoff the station of koopal number 3 was selected and its average discharge and rainfall were surveyed during the years 1982 - 12014 and 1982 – 2012 respectively and the soil conservative service method of USA along with GIS and RS tehniques were used.The results showed that the average annual discharge rate of the Koopal River was, 2.49 m 3/s, so that the highest was in winter and the lowest was in summer. On the other hand, the results showed that the studied area from the southeast of Ahwaz can produce an annual runoff volume of 34.14 million cubic meters Which is 31 million cubic meters in fall and winter seasons. Therefore, regarding the annual runoff volume of koopal River and the southeast dust source of Ahwaz, especially in the winter season because of the increasing in the frequency of south-eastern wind as the main cause of dust storms phenomenon, to carry out the operations of watering and restoring vegetation cover with a proper management water usage plan in the upstream of the river.

The purpose of this study was to investigate the characteristics of wind regime and sand transport potential in the Sarakhs Erg, located in the north-eastern corner of Iran. Accordingly, using the data of wind speed and direction (1978-2016) of the Sarakhs synoptic station, the potential of sand transport (DP), Resultant Drift Potential (RDP), Resultant Direction Drift (RDD), and the ratio of RDP/DP were calculated using Fryberger-Dean (1979) method. Also, the characteristics of erosive winds and temporal changes were investigated based on sand transport (DP) potential. The results showed that the dominant wind direction and the sandy wind were northwest. Agricultural lands, especially in the fall season, as well as the sediments of the Tajan Border River, were the sources of wind sediments. In general, wind energy in the Sarakhs region based on the sand transport (DP) potential is put in the low class (DP=193 v.u) with the highest and the lowest in July and November, respectively. On the other hand, sand discharge capacity based on the average sand carrying potential (DP = 193 v.u) for this range was estimated to be about 13.51 m3 in width. Field studies and satellite images showed that sand and nebka zones were two main forms of wind sediments in Sarakhs Erg sediments.

Wind, as a major driving factor on soil erosion in arid and semi-arid areas, needs to be investigated precisely to prevent its undesirable effects. The main purpose of this research was to determine the spatial variability of wind erosivity and sand drift around Urmia Lake. For this aim, the anemometry data of eight synoptic stations adjusted to the Lake were analyzed for the whole period time. Annual wind-roses showed that despite the very high spatial and temporal changes of wind variables (speed and direction), major prevailing winds were blown from the East and West, respectively. Also, annual storm-roses depicted that the erosive winds blew mainly from South and Southwest direction. These winds had a unidirectional regime in summer and spring, while in fall and winter, a multi directional regime was observed. The results of calculated sand drift power by Fryberger and Dean Formula indicated a low to moderate class of wind erosion potential and the final direction of sediment transport was mainly to northeast. According to the Letu-Letu equation, sand transport flux is varied between 0.05 to 0.76 Ton/m/year. Although the windiness of study area is moderate, the Tsoar sand mobility index is less than one, indicating inactive sand dunes. However, due to the low vegetation established on the sand dunes surface, it can be drawn that the role of human factors (especially cattle grazing and trampling) as well as the salinity caused by the drying of the Lake are responsible for this situation.