جستجوی مقالات مرتبط با کلیدواژه « Desertification » در نشریات گروه « آبخیزداری، بیابان، محیط زیست، مرتع »

The purpose of this research was to evaluate the intensity of desertification and its impacts on the reduction of vegetation in Shir Ahmad Wildlife refuge in Sabzevar township of Razavi Khorasan Province. To evaluate the intensity of desertification, the ESAs model and the three criteria of climate quality, vegetation and human management were used. The results of this research showed that based on the ESAs model, desertification occurred in the study area during the years 2008 to 2018 and its trend was increasing. Thus, in 2008, 64.9% of Shir Ahmad region is in the severe hazard class and 35.1% of the other lands in the region are in the moderate hazard class. However, in terms of the intensity of desertification and ecological conditions in 2018 about 68.5% of lands are in the severe desertification hazard class and 31.5% are in the moderate hazard class. The results of this research showed that in the last 10 years, the continuation of the drought and changes in climatic parameters along with human activities have been the main causes of the desertification expansion and vegetation reduction in Shir Ahmad Wildlife refuge. Therefore, significant methods should be taken regarding the preservation and sustainability of this area in order to prevent the destruction of plant and animal species. Some of the measures such as reducing the grazing pressure of domestic animals from the pastures, replacing industrial animal husbandry methods instead of the traditional method, implementing land restoration programs and providing fodder for wildlife, will be among the proposed programs for the management and protection of Shir Ahmad Wildlife refuge.

Iran has an area of about 165 million hectares and is located in arid and semi-arid regions. According to the latest data provided by the Natural Resource and Watershed Management Organization, about 110 million hectares of the area of Iran is at risk of desertification. At present, more than 32 million hectares of the country's deserts are more than 32 million hectares, of which over 5.7 million hectares are highly exposed to wind erosion and are considered as dust storm sources. In general, desertification refers to the development in which natural resource areas are confronted with intensification of soil erosion, a reduction of fertility, and exit from the production area. Iran is one of the countries in the world where the desertification rate is high. In order to seriously deal with the phenomenon of desertification and implement desertification plans, desertification activities should be considered as economic activities, while creating a context for the return of investments, it follows the cooperation and participation of the people. A research project was defined and implemented in the Research Institute of Soil Conservation and Watershed Management Research Institute with the aim of applying and developing successful model/models of dealing with desertification and the economic development of desert areas in Iran and the world. In this plan, the most successful models implemented in the world were examined and finally, the economic desertification plan of the Kubuqi desert in Inner Mongolia, which has been successfully implemented in China, was chosen as a model to be examined in some desert of Iran. However, it is not possible to use a single method for all desert areas. Due to the diversity of deserts, including factors of desertification and resource capacity, the use of experience and executive components of successful plans should be customized for the target area. The success of the Kubuqi model, which has been carefully examined in the analysis of management processes, attracts private investors and people’s participation. On the basis of the analysis results, Reza Abad village in Biarjmand city, Shahroud district, Semnan Province was selected as a pilot region to conduct preliminary studies and provide a development model for desert reclamation, which will be discussed in this paper.

Extreme precipitation has a significant impact on the frequency, severity, and duration of natural hazards, such as floods, droughts, and landslides. This has a significant impact on human life, the economy, natural ecosystems, and agriculture (Song et al, 2015: 34). Between 1880 and 2012, there was a 0.85 °C increase in the average global temperature, with a general increase in precipitation in the mid-latitudes of the Northern Hemisphere (IPCC, 2013: 2; Lio et al, 2017: 822). In addition, there is a possibility of a rise in extreme precipitation in the future (Klein Tank et al, 2006: 1), and so far, the reason for these changes and their relationship with the general circulation of the atmosphere have not been considered. The aim of this study is to analyze the trend of changes in extreme precipitation indices in northwestern Iran and its association with the general circulation of the atmosphere.

In order to analyze the changes in extreme precipitation events in northwestern Iran, daily precipitation data was collected from 20 synoptic stations in the region between 1986 and 2010. The region that is being studied encompasses West Azerbaijan, East Azerbaijan, Ardabil, Zanjan, and Kurdistan. In assessing limit events, high quality and reliable long-term climate data with daily (or higher) resolution is required (Clintanak et al., 2009: 9). The first step was to examine the quality control and homogeneity of data. The RClimDex software package, introduced as a standard tool by ETCCDI, was used to perform quality control and evaluate data homogeneity in this research. The Expert Team on Climate Change Detection, Monitoring and Indices (ETCCDMI) introduced 11 indexes to examine changes in precipitation level indices in northwest Iran. RClimDex software calculates these indicators with a significance level of 0.05. This process seeks to establish a standard set of indicators to examine and compare the characteristics of different regions. The software was used to calculate precipitation indices and display the trend and rate of change on a map.

The extreme precipitation indices were calculated to determine the regional trend and percentage of stations with positive and negative trends for the studied stations in northwestern Iran. Afterward, a map was created showing the spatial distribution of the slope for each of the indices. All precipitation indexes, except for the maximum growth period index (CDD), are declining according to the results. The probability of precipitation has decreased due to the more stable winter atmosphere in the region from the point of view of general atmospheric circulation. The region's spring atmosphere, similar to that of winter, shows an increase in stability, which will result in less rainfall. In summer, except for the coastal provinces of the Caspian Sea and the coasts of the Oman Sea, the rest of the country has recorded a decrease in rainfall of 1 mm per day. Most parts of the country experienced an increase in atmosphere thickness to 6 meters in autumn in the study area. Autumn in the region is typically stable and barotropic, but the study area is experiencing less rainfall. This study examines the trend of changes in extreme precipitation indices in northwestern Iran and its relation to a large-scale general circulation of the atmosphere. According to the results, 75% of stations in the region are experiencing a decrease in the maximum daily rainfall (RX1day) and 80% are experiencing a decrease in the maximum five-day rainfall (RX5day). While both the very wet (R95P) and ultra-wet (R99P) day indices are experiencing a downward trend, the R95P index is experiencing a more pronounced downward trend. All three indices R10, R20, and R25 have been declining for the past 25 years, but the R10 index has fallen more rapidly than the other two indices. Sarab station has a positive CWD trend alone, while other stations have a negative and decreasing trend of this index. In most stations throughout the region, the CDD index is increasing. In 85% of stations in the region, the PRCPTOT index is decreasing and there is a noticeable increase in rainfall. The SDII index is experiencing a decrease in 60% of the stations in northwestern Iran, while an increase is being observed in 40%. All precipitation indices, except for the CDD index, have a decreasing trend in general. Drawing and analyzing combined difference maps for geopotential height parameters of 500 hPa, relative rotation of 500 hPa, vertical velocity (omega), rainwater and precipitation rate to study the general atmospheric circulation of the region indicates an increase in altitude has led to a 500 hPa increase in climate stability in the study area (northwest of Iran). The study of omega and relative rotation shows that the region is experiencing a decrease in upward currents and positive rotation. The lack of atmospheric moisture load and rainfall in all seasons can be seen in rainfall water difference maps and rates. Precipitation indices and the general circulation model of the region's atmosphere are compared, indicating that the moisture load of the region's atmosphere has decreased, resulting in drought.

Population growth and the excessive use of natural resources have caused significant changes in natural ecosystems, including a decrease in rainfall and an increase in temperature. The potential exists for them to decrease vegetation and increase barren areas. Serious economic, social, and environmental damage can occur in natural ecosystems due to the destruction of land cover and other damages, such as dust storms. Therefore, ecosystem changes are taking place worldwide, both at the temporal and spatial scale, due to human activities and natural factors. So, investigating the amount of land use/cover changes, their effect on dust storms, and predicting these changes for the coming years can be an important step in reducing and controlling unprincipled changes, planning, and optimizing resource. Climate change and human activities, such as drought, human activities, and non-compliance with water rights, have a significant impact on the Hamon wetland area, so that the dry bed of the wetland has become the main sources of dust. This research is focused on investigating the impact of land use changes on dust storms and forecasting land use changes in the Sistan region for the next 20 years.

The impact of land use changes on dust storms in the Sistan region was examined using Markov chain forecasting methods. For this purpose, first of all, the land use maps of 2002, 2011 and 2022 were prepared using satellite images. An anomalous method was used to investigate climatic parameters, including temperature, rainfall, and the number of days with dust, in the next step. To evaluate climatic changes, it is necessary to use a method that shows long-term changes. The anomaly method was employed for this purpose. The values of this index can be either positiveor negative. In order to predict land use changes for the next 20 years, the combination of the maps of 2002 and 2022 for severe drought conditions were used by using Markov chain and Cell models. The Markov model was predicted to generate multiple images. The transfer probability matrix allows for the expression of the probability that any type of land cover will be found in any location in the future. Despite the accuracy of transmission probabilities for each user is unknown, due to the lack of information on the spatial distribution of users, the Markov model does not have any spatial dependence information.  In contrast, to the automatic network, it is an agent that has the ability to change its state based on the application of the law that shows the new state in accordance with the previous state and the state of its neighbors.

This study examined the impact of land use change on dust in the Sistan region. At first, climatic changes of temperature, rainfall and number of dusty days were investigated and the results showed that the temperature has increased and rainfall has decreased in the Sistan region during the last two decades. The land use maps also showed that in the years when the Hamon wetland has been drained, pastures and dense vegetation have increased and barren lands and salt marshes have decreased. But due to the recent droughts like the year 2022, when a drought has occurred in the region, the use of vegetation and pasture has decreased and barren and salt marshes have increased. These conditions cause an increase in the level of dust in the region. The land use map for severe drought conditions in the next 20 years was predicted using the Markov model.  It showed that in the future, pastures and dense vegetation will decrease, but barren lands and salt marsh areas will increase dramatically. As desertification and wind erosion increase, dust storms will also increase as a result of these conditions. The economic, social, environmental, and health conditions of residents in the region are adversely affected by dust storms. Therefore, proper planning and management can reduce the damages caused by dust storms in the Sistan region.

The excessive use of water and soil resources, especially in arid and semi-arid regions, causes increased soil erosion, followed by the appearance of destructive floods, the emergence of dust, and intensifying the phenomenon of desertification. Therefore, in order to prevent the environmental problems of these areas, there is a need for efficient management of their water and soil resources. The rainwater catchment systems are one of the strong points of dry and desert areas, which have a high ability to develop these areas. This study investigated the effect of rain catchment systems on the physical and chemical characteristics of rainwater catchment systems soil in the Mil Nadir area of Sistan. For this purpose, six soil samples were taken from the rainwater catchment systems and the control area and their physical and chemical properties were measured. The results of this study showed that there is a significant difference of 1% between the average percentage of clay, silt, and sand in the soil of the rainwater catchment systems areas compared to the control area (P<0.01). With the increase in the percentage of clay and silt, the soil texture from class Loamy-sandy in the control area was changed to loamy class in rainwater catchment systems, which caused a 28% increase in soil moisture compared to the control area. In the examination of soil chemical properties, the findings indicate that the amount of acidity, electrical conductivity, sodium, and sodium absorption ratio significantly (P<0.01) in the soil of rainwater catchment systems decreased, but the amount of organic matter, nitrogen, and potassium increased. The effect of rain catchment surface systems has improved the physico-chemical properties of the soil, due to the existing environmental crises and the acceleration of the desertification process in this region. The use of these catchment systems in the Sistan Region provides suitable conditions for improvement. It provides ecological and environmental protection of these areas.

The positive economic and social effectiveness of rangeland restoration projects activates the process of sustainable development and leads local communities to sustainable prosperity. The purpose of this study is to assess the socio-economic and environmental effectiveness of restored rangelands with Atriplex canescens plantation in Mallard county, Tehran province, Iran. The descriptive-analytical research method based on questionnaire was applied within the statistical population including 65 experts, 132 pastoralists and 29 local communities. The selection of samples was random and sample size were determined using Cochran's formula for three groups of experts (55), pastoralists (99) and local communities (27). To determine the validity of the questionnaire, a group of experts were used and Cronbach's alpha coefficient was used to estimate the reliability of the questionnaire. Also, Kruskal-Wallis test was used to compare opinions of the studied statistical societies. The results of the comparison of economic, social and environmental indicators showed that A. canescens plantation had a significant effect on social index and had no effect on the other two indicators. Social- environmental effectiveness of planting A.canescens is related to increasing livestock products and improving the condition of ranching, According to pastoralists, the greatest economic, social and environmental effectiveness from planting A.canescens has been related to increasing livestock products and improving the condition of ranching, increasing the level of public awareness. In general, results of effectiveness planting from the point of view of all three groups are close to each other and they often agree on the effectiveness of planting Atriplex. This alignment in thinking of plantation will lead to success in the implementation of projects and the achievement of goals and perspective,.

 as one of the most critical environmental challenges in recent decades which has engendered environmental pollution worldwide (33, 3, 2), wind erosion occurs due to increased velocity and turbulence of the wind when blown on a cover-free surface (11), inflicting lots of economic and social damage on various sectors.There are several methods used to reduce wind erosion, including biological methods (seeding and planting), mechanical methods, and the methods used for strengthening the surface cover such as the application of different types of mulch (oil, polymer, biological, and mineral mulches) (21). In this regard, mulching should, as a last resort, be able to pass rainwater, penetrate into the ground, and maintain moisture while having sufficient required adhesive strength.Non-petroleum materials have increasingly been used in recent years to improve the stability of buildings, aggrandize the diameter of soil aggregates, and stabilize the soil against wind erosion. However, choosing a material as a soil stabilizer against wind erosion, replacing new mulch instead of oil mulch while considering the aforementioned factors, and taking the biodegradability of the non-petroleum materials into account are other crucially important factors to note in this regard. Therefore, this study sought to investigate the effect of mineral mulch (a combination of CaCl2 and MgCl2) on soil properties.

 The study area covered the sand dunes of the Rigboland desert located in Aran and Bidgol city, Isfahan. The mineral mulch used in the study was a stabilizing solution obtained from the evaporation of the brine of Iran’s central desert in the Khorobiabank region, known as the SS400 soil stabilizing solution (27). Chemical analysis of the solution indicated that it contained 30% CaCl2, 15% MgCl2, 5% NaCl, KCl, Ca (NO3) 2, and 50% water whose pH ranged between 5 and 6, with an average specific gravity of 1.5 g / cm3.On the other hand, in March 2012, mulch was sprayed directly to the natural field with three replications on three mounds of incomplete Barkhan-type sand dunes in Rigboland Aran and Bidgol regions to evaluate the influence of mineral mulch on soil’s chemical properties (Figure 4). To this end, samples of aeolian deposits were collected from three different depths of the hills in the study area with three replications (0-5 cm for the first replication with and without mulch; 5-10 cm for the second replication; and 10-20 cm for the third replication) prior to performing mulching. Finally, some samples were collected once more at the end of the experiment in May 2014 from the same three depths. It should be noted that 15,000 liters of mulch were applied per hectare.

 The results of paired T-test performed on the characteristics of different soil depths suggested that the mulched aeolian deposits did not differ significantly in both control and treatment groups in terms of N, CaSO4.2H2O, P, Cl, and OM characteristics in at all the depths studies (P> 0.01). However, the application of mineral mulch significantly increased the EC, pH, Ca, K, and CaCO3 at all depths, and N and Mg at the first and second depths (P <0.01).Mulches with different compositions and origins may increase or decrease the root's ability to absorb elements. In this regard, the current study found that mineral mulch significantly increased the soil’s pH (P <0.01), which could be justified if the Na and CaCO3 added to aeolian deposits as a result of applying such a mulch are taken into account.Furthermore, hydrolysis of Na and the dissolution of CaCO3 which eventually lead to the formation of hydroxyl anions could be regarded as the main cause of such an increase in the aeolian deposits’ pH under treatment mulch. Moreover, the comparison of the deposits’ pH made as a result of sampling with and without mulch revealed that the deposits’ pH would be higher if they are sampled with mulch, which can be justified according to the explanations provided above. On the other hand, some studies have reported that the aeolian deposits’ PH increased when treated with mulch (17), which is consistent with the results obtained in this study. However, the finding does not correspond with the results reported by some researchers (20 and 4).The significant increase in EC capability at different depths of the treatment group compared to those of the control group clearly confirms the influence of mulch on increasing the soil’s EC. Moreover, examining the soil’s EC capability at the evaluated depths showed a decreasing trend caused by the washing and transfer of the mulch-included solutes to lower depths, where the rate of ion transfer decreased with an increase in the soil’s depth.Also, mineral mulching significantly increased the soil’s K (P <0.01), which could be justified by considering the type and the origin of the mulch used, taking into account the fact that the initial solution was prepared by using the materials collected from the study area contained high amount potassium, a limited portion of which still remained active even after it was extracted from the solution (what remained from the solution afterward was used as mulch), causing a significant change in the amount of potassium in the soil. This finding is consistent with the results reported by some researchers (10, 13, and 14) who argued that mulch increased P and K in the soil.

 Considering the findings of this study in terms of the influence of mulch on the aeolian deposits’ componential elements and important chemical properties, including the deposits’ response, electrical conductivity, sodium absorption ratio, and the percentage of the exchanged sodium, all of which showed an increasing trend that led to salinization and alkalization of the deposits, and consequently to physiological dryness, and taking into account the fact that the mulch exerted no influence on the percentage of the aeolian deposits’ organic matter as the most important and effective factor in improving the physical, chemical, and biological conditions of the deposits, it could be argued that the mulch used in this study had no positive effect on the aeolian deposits studied. Therefore, this mulch is not recommended for stabilizing sand dunes and controlling dust.

Land degradation is manifested by a significant decrease in biological productivity of land, as a result of natural events or improper human activities. The unfortunate consequences of this degradation are threats to food security, economic well-being and environmental problems caused by the reduction of the exploitation potential of water, soil and plants. The aim of present research is to compare and measure the state of land degradation based on two global GLASOD and Iranian IMDPA models. The great plain of Yazd-Ardakan located in central Iran was selected as the research area. The land unit map of area was prepared. The severity of land degradation was investigated based on the GLASOD and IMDPA models in each of the land units. Accuracy assessment and comparison of both models’ performance were done by calculating overall accuracy and kappa coefficient, as well as non-parametric tests of Spearman and Mann-Kendall, and the significance of the results were confirmed. The comparison of accuracy assessment results showed that the IMDPA production map matched the actual data on the ground by 82%, while this match in the map obtained by GLASOD model was 69%. According to the IMDPA and GLASOD models, desertification was progressing strongly in 33% and 12% of the region, respectively. The intensity of desertification in the moderate class was approaching the severe class, and if there is no proper management to control and prevent the desertification process in the region, in not-so-distant future, the area of land with severe desertification will increase. In general, the lack of soil surface cover is the main factor in increasing the intensity of desertification in the Yazd-Ardakan plain. This issue is result of combination of natural factors and destructive human factors in the region, which has significant effects on increasing the desertification process and soil degradation.

Soil salinity is a major cause of desertification. It can be caused by several factors including and not limited to improper irrigation, low irrigation water quality, saline groundwaters, saline geological formations, and improper land management. Since direct measurement of soil salinity is costly and time-intensive, the main purpose of this research is verifying whether satellite remote sensing data can be used as a proxy to estimate soil salinity.

In the present study, soil salinity changes in Torbat Heydariyeh city of Khorasan Razavi province were investigated using MODIS satellite data in the period of 2005, 2010, 2015 and 2020. We used a combination of MODIS visual images band 4 and 6 to produce the salinity index. In order to evaluate the alternative indices and the effect of salinity on other environmental variables, the correlation between salinity, altitude, slope and EVI (Enhanced Vegetation Index) was also examined. To prepare the ground truth map in 2020, a field sampling was conducted in late June of 2020 from the top 0-5 cm of soil surface in a random sampling design from 80 points. Soil salinity was determined in saturated extract. The obtained salinity values were compared with the equivalent values in the 2020 salinity map based on the kappa index to determine the accuracy of the calculations.

Although the salinity level in the region is not very high, but the trend of change indicates an increase in salinity in the region, mainly in the southern and central parts and parts of the north of the region. In terms of topography, most of the area is flat with minor elevations in the middle and northern section. Soil salinity is believed to be correlated with the topography of a region. Salts tend to accumulate more in the lowlands and highlands become saline only if their parent formation is saline. To investigate the effect of this factor on soil salinity distribution in Torbat-e Heydarieh, an accurate digital altitude map of 12.5 meters resolution from the ALOS satellite was used. The correlation between salinity, altitude and slope was evaluated at different times. However, this relationship was not significant in any of the studied periods. But the interesting point was the higher correlation between salinity and altitude, which seems reasonable considering the distribution of evaporitic and Marine formations in the plain areas. We did not obtain significant changes in vegetation in the region between 2005 and 2020. If one would divide the EVI index results into three cover classes, 60% of the area would be classified as without coverage or with very poor cover (2235 square kilometers), 20% as medium (745 square kilometers) and high (745 square kilometers), respectively. Most of the vegetation of the region is scattered in the northern plains on the alluvial sediments. Accordingly, ​​approximately 60% (2235 square kilometers) of the total areas fell in the class of no salinity (0-0.17), 35% (1304 square kilometers) in light salinity (0.17-1.2) and only 5% of the area (186 square kilometers) in the extreme class (more than 0.2). To confirm the validity of the salinity index, the salinity measured in the field was compared with the corresponding values ​​from the produced map and the kappa coefficient was equal to 0.65%, indicating the validity of the measurements performed. However, the correlation between different parameters and salinity showed no correlation with slope, altitude and EVI, which is conceivable due to the scattered vegetation of the area. Interestingly, the values ​​of height and slope correlations were higher than vegetation. It seems that the severe lack of vegetation and the accumulation of evaporative formations in a few spots have led to a lack of correlation between these factors.

The results of soil salinity estimation in Torbat Heydarieh showed that remote sensing data is a viable alternative to direct soil salinity measurements. However, soil salinity did not correlate with other environmental factors including vegetation cover, altitude and slope gradient. Therefore, these factors cannot help us as proxies of soil salinity in these arid areas. According to the accuracy of the salinity index, it can be used to monitor salinity in the region. These results can help land managers to deal with salinity and ultimately desertification.

Desertification is a problem that is currently affecting many countries in the world, including Iran. This problem is seen not only in arid and semi-arid areas, but also parts of semi-humid areas. The purpose of this study is to investigate and zoning the intensity of desertification using the modified Medalus Model and hierarchical clustering method in the Baqous Plain of Sabzevar. For this purpose, effective criteria in desertification including climate, vegetation, soil, erosion, and selection management, and the geometric mean of the indicators were calculated. Data layers indicators related to each criterion were prepared using the GIS system. This information was scored based on the Medalus method and from the geometric mean of the indicators of each criterion, the final map of the status of each criterion was prepared and from the geometric mean of the criteria, the current map of the desertification of the region was prepared. Results showed that the criteria of vegetation, climate, and erosion were more effective than other factors in desertification of the region and high sensitivity and critical type was matched with the poverty of vegetation and the dryness of the climate, and work units 1 and 2 have the largest area of desertification types with high intensity. The results also showed that 21% of the study area is in the high sensitivity zone, 28% in the high and critical sensitivity zone, 17% in the low sensitivity zone, 28% in the low and critical sensitivity zone, and 6% in low sensitivity zone to erosion. 55.6% of the results of modified Modalus Model were obtained by significant clustering methods. According to the spatial distribution map of desertification intensity extracted from the model, it can be used as an auxiliary tool against desertification and prevent excessive destruction of the region in the future.

Desertification has been considered as a serious threat to arid, semi-arid and even semi-humid climate in recent decades and it is a major obstacle to sustainable global development, so monitoring its changes is urgent. Using remote sensing and GIS is one of the cost-effective, often free and accessible method to monitor changes in these areas. In this study, change vector analysis method was used for evaluation and analysis of desertification change in a part of Ghalehganj county in south of Kerman province. For this purpose, Landsat 8 image bands in two time periods of 2014 (first period) and 2020 period (second period) for March and April was used in Google Earth Engine. Image pre-processing were applied and averaging was done separately for both periods which was followed by calculation of EVI and BSI indices. For the next step, using these two indicators and the change vector analysis method in the GIS software, the magnitude and direction of desertification change trends were determined. The results of the present research indicated the dominance of the reclamation process in the region during the years studied and the overall results indicate that development of cultivated lands and land use change have the greatest impact on monitoring indicators and desertification trends in the region. Thus, degradation of lands around residential areas are witnessed and on the other hand, there is a significant relationship between agricultural activities and rehabilitation areas in the region.

Wind erosion causes land degradation in arid and semiarid regions and is a serious challenge for sustainable production and farmland management.  Therefore, it is necessary to identify the factors affecting wind erosion and wind erosion potential in each area and use them in planning. Wind erosion conditions exist mainly in arid and semi-arid climates of Iran (large parts of the central and eastern regions) at the same time and in today's situation, it has intensified due to improper management.

In this research, in order to determine and estimate the wind erosion potential of Chahdashi region of Nehbandan city of South Khorasan province, IRIFR.2 model and capabilities and facilities of ArcGIS10.3 software have been used. Given that the IRIFR model calculates wind erosion potential in geomorphological facies, in this research, geomorphological facies of the region were identified using basic maps including topography, DEM, geology, vegetation, land use and field visits,. IRIFR.2 model is introduced to estimate erosion of arable lands. This model enables the user to estimate the wind erosion potential of the field according to the questionnaire, seeing the effects and signs on the soil and field surface. To determine the amount of wind erosion of agricultural lands In IRIFR. 2 model, 9 factors including sedimentology of soil texture or land sediment, topography and location of the studied lands, wind speed and continuity of strong or erosive winds, roughness or the degree of unevenness of soil surface, impact soil compressive strength and turbulence, soil moisture and irrigation conditions, salt content and type of salts in soil and irrigation water, density of vegetation and straw remaining over the ground surface, and farm management (planting patterns, presence of windbreaks around the field, crop rotation) were examined. The score of each factor was determined and the score of these factors was added together.The deposition potential was then determined. After calculating the amount of erosion, the classification of erosion intensity was determined and finally the sediment potential and erosion intensity were mapped in each facie.

In the study area, 22 facies were identified and the facies of Rig-e-Danehriz plain, with the code 3-3-2 and with 29.5%, have the highest percentage of area and the area of agricultural lands, rangelands and uncovered lands were respectively 0.33, 99.03 and 0.64% of the available rangeland plants of 13 plant types. Erosion intensity class in different facies varies from very high to very low. Field visiting showed that areas with very low erosion have high rock cover. In fact, there is no soil for erosion in these areas. Accordingly, Arable lands have less potential for erosion than other work units. The results of the quality status map of the wind erosion intensity of this model showed 5 classes, of which 8.3% of the area is in the very low class, 28.6% in the low class, and 57.5% in the middle class. Vegetation, surface gravel and hardened clay surface prevent wind erosion in these areas, 1.8% in high class and 3.8% in very high class, which mostly includes active sand dunes. The highest erosion intensity score is related to the landuse of ripple and silk hills with facies code 1-3-3 and with a total score of 9 factors equal to 107, Qualitatively, it is related to the severity of erosion and covers 3.8% of the area. Also, the lowest score of wind erosion intensity belongs to stone outcrop unit with 1-1-1 facies code and total score of 3.8, which is qualitatively characterized by very low erosion intensity and the area of this unit covers 1.5% of the area. Agricultural lands are in the low erosion intensity class in terms of erosion potential with 3.2 tons per hectare per year.

According to IRIFR.2 model, the main factors contributing to wind erosion in Chahdashi area are environmental factors because environmental factors (wind condition and vegetation) with the highest scores were identified as the main factor in most work units. The wind erosion potential of the studied area in all facies is more than the soil potential of the region (due to climatic and edaphic soil conditions), wind speeds more than 4 m/s and also the lack of vegetation and in some facies the presence of soil particles sensitive to erosion, are the most important reasons for wind erosion in the region. The rate of erosion in the hill facies is 86.3 tons per hectare, which is the highest among the geomorphological facies of the region. Due to the favorable conditions for wind erosion, especially the lack of adhesion between soil particles, this facies has a deposition rate of more than 6000 tons per square kilometer per year.

Desertification is an important issue in many countries around the world, including those which are located in arid and semi-arid regions. Land degradation in arid and semi-arid regions provides the conditions for desertification due to climate change and human activities. In other words, desertification is a process which leads to the destruction of the land and its resources. Nowadays, it is necessary to know the exact criteria and indicators affecting the occurrence of desertification in order to provide a model to show the severity of degradation and determine the most important factors affecting it. Therefore, using Multi-Criteria Decision-Making (MCDM) methods and recognizing internal and external factors (strengths, weaknesses, opportunities and threats) to identify and evaluate the process of desertification and land degradation enable one to obtain the best options and plan appropriately for desertification management for its management. This study aims to provide solutions for desertification management in Yazd-Ardakan plain based on SWOT model.

The study area is Yazd-Ardakan plain, which is located in the central part of the central plateau of Iran. In this plain, due to environmental conditions, resources must be managed and used in such a way that the resources available are not destroyed. The purpose of this study is to provide desertification management solutions in Yazd-Ardakan plain based on SWOT model. For this purpose, internal and external factors affecting the desertification process in the plain were determined by Delphi method and summarized by SWOT model. Also, desertification control strategies were presented and Strengths, Weaknesses, Opportunities and Threats (SWOT) were examined. After internal and external factors were identified and the final score of these factors was obtained, using the quadratic matrix of internal and external factors, the desired solutions were selected from the proposed solutions.

The results showed that the final score of internal and external factors affecting desertification is 2.65 and 1.96, respectively. Therefore, the best strategies to control desertification in the Yazd-Ardakan plain are to deal with threats. However, due to the nature of desertification and the complexity of this phenomenon, it is important to pay attention to all solutions. In other words, using all of the solutions can guarantee the control of desertification in this region. Regarding the strengths and weaknesses of Yazd-Ardakan plain in relation to the control of desertification phenomenon, it can be said that the strengths have a relative advantage over the weaknesses, which is evidenced by the sum of internal factors (2.65). Having said that, the advantage is not great and the weaknesses of the region have a high score and show their high importance along with their strengths. The arid climate of the region and successive droughts,wind erosion centers in the region along with traditional agriculture with high water consumption and low efficiency, the concentration of environmental polluting industries and insufficient control over them have made it difficult to revive the desert despite the strengths of the region. Therefore, in order to determine desertification control strategies, it is very important to pay enough attention to the weaknesses along with the strengths. The close scoring of most of the internal factors of the region in relation to the phenomenon of desertification illustrates this well.

Regarding the opportunities and threats in Yazd-Ardakan plain in relation to the control of desertification phenomenon as well as internal factors, it can be said that the advantages of all factors are close, which shows the high importance of all factors. The difference between external and internal factors in the Yazd-Ardakan plain in relation to the phenomenon of desertification is the relative superiority of the negative points of the region over the positive points in relation to desertification, which is evidenced by the total score of external factors. In the case of external factors, as well as internal factors, social and economic issues have shown great importance.The existence of the idea of ​​full preference of industrial and mining activities over environmental protection and the possibility of transferring labor from agriculture to industry and mining scored highest. Therefore, the strategies that can solve these problems can be considered as the most important strategies. The results of this study in choosing a solution to control and manage desertification in the Yazd-Ardakan plain, given the high importance of all internal and external factors, can guarantee desertification control in this region.

Community participation in desertification projects lowers costs and makes projects more effective. Through strategic policies for the restoration, conservation and sustainability of natural resources, the government is implementing programs, and individual, cultural, social and economic factors play an effective role in increasing the participation of villagers in desertification projects. The objective of this study was to study and prioritise factors affecting the participation of villagers in Mohammad Shahkaram area of Zahak city, where desertification projects have been implemented in its northern zone. Data collection tool is a questionnaire. According to Cochran's formula, the number of samples required was 358 questionnaires and for questionnaire reliability, 30 questionnaires for the sample were tested in advance. The analysis of the data was based on descriptive statistics and inferential analysis. Results of the AHP method and multivariate regression analysis showed that the independent entered variables can predict 57% of the variables related to the village participation rs in desertification projects. Among the variables studied, age and work experience of individual factors with a Pearson coefficient of 0.216 and local responsibility from social factors have the highest correlation with participation rate.  Maintaining desertification projects in the region puts in the first rank, and sociocultural index factors have a higher priority than variables dependent on participation in desertification projects than economic index and planning.

Nowadays, desertification and land degradation are among the most important environmental chalenges caused by various factors, including climate variation and human activities, especially in arid and semi-arid regions. Therefore, understanding of the desertification status is essential for future management and planning. In this regard, using remote sensing indicators to prepare basic desertification maps and its monitoring can be efficient. In this study, Topsoil grain size and albedo indices were used as indicators to identify desertification in the center of Khuzestan province. After constructing the above-mentioned indices using Landsat ETM+ sensor image, the values of 411 randomly selected samples on the images were used to construct the Albedo-TGSI feature space model. The correlation between the variables was 0.83. The DDI desertification degree equation is then obtained based on the slope of the fitted line. In the next step, by applying natural break classification on the DDI index, different levels of desertification and the break values ​​were obtained for random samples. These break values ​​are then applied to the whole study area, and finally, the 2018 desertification status map was obtained. Results indicated that about 70% of the study area fell under the severe and high desertification intensities, whereas 18.3%, 8.3% and 4.1% fell under the medium, low and none desertification grades respectively. The accuracy of the produced map with a kappa of 92.1% and an overall accuracy of 94.3% showed that the feature space model is a useful and robust tool for extracting desertification degrees in barren lands or areas with extremely low vegetation coverage.

Desertification is defined as the reduction of the ecological and biological potential of the earth, which occurs both naturally and artificially. This phenomenon is one of the important problems of countries for sustainable development management programs, which is the result of a combination of various environmental, human and climatic factors. Water is recognized as an important and influential factor that is the main source of life and also guarantees the survival of sustainable ecosystems. Since water is more important in arid and semi-arid climates than in other climates, measures should be taken to properly manage water in order to prevent critical conditions in these areas. The purpose of this study is to investigate the status of water criteria to assess desertification. Due to the many effects that water indices have on the development of desert areas, in our study, we used quantitative and qualitative indices of groundwater such as electrical conductivity (EC), sodium absorption ratio (SAR), color (Cl), falling groundwater level and irrigation systems to study and determine the class of desertification intensity in Mehran plain. The IMDPA model was applied to evaluate the desertification situation. The results showed that the indices of decline and irrigation systems with average values of 3.11 and 1.75, respectively, have the greatest impact on the desertification process in the region. According to the groundwater status map in the destruction of resources in the study area, it can be concluded that 32% of the total area is in the low class, 48% in the middle class, and 20% of the total area is in the severe desertification class. In general, water resources management should be a priority for executive agencies to prevent desertification.