Risk assessment provides the possibility of planning and management to prevent and reduce the Risk of Desertification. The present study is aimed to assess the hazard and Risk of Desertification and to develop management programs in the semi-arid western regions of Golestan Province in Iran. Desertification rate was obtained using the Iranian model of Desertification potential assessment. Since the rating system was considered for the indicators, data analyses were carried out according to the Mann-Whitney test. The Risk of Desertification was calculated based on hazard, elements at Risk and vulnerability assessment maps. The intensity of Desertification was estimated to be medium. Among the factors affecting Desertification, agriculture by the weighted average of 3.22 had the highest effect, followed by soil, vegetation, water and wind erosion criteria by weighted averages of 2.45, 2.32, 2.15 and 1.6 respectively.Desertification Risk assessment results also showed that about 78% of central and northern parts of the region, with the largest population and residential centers, surface and underground water resources, agriculture and horticulture, is confronted with a high to very high degree of Risk. Management plans and control measures, based on Risk values were presented in four activities (with two management priorities under critical and non-critical conditions). For the management program with the largest area. Control measures and strategies such as the establishment of halophytic and xerophytic plants, drainage networks, resilient facilities and infrastructure were proposed. Reducing the Risk of Desertification, could play a crucial role in the sustainable development of drylands and desert ecosystems.

Iran is mostly consisted of arid and semi-arid areas. Rudab region, Sabzevar, is indicative of an area exposed to and affected by the Risk of Desertification. This study accordingly is aimed at assessing the Risk of Desertification using ESAs model, through mapping the Risk of Desertification. Initially, work units’ map was prepared based on which relevant indicators were valued. Then, relevant indices were prepared based on ESAs model using GIS. Finally, ESAI index was calculated for each work unit. After mapping the Risk of Desertification, Desertification damages were evaluated. It was found out that the Risk of Desertification in Rudab can be classified at three classes i.e. class I, II, and III; and subclass III1 covered the biggest surface of the study area i.e.44.48%. Based on Desertification damage map, Rudab region is divided into five classes so that class III covering 35.20 percent of the area is the biggest area. Active sandy dune faces are prone to the highest Risk of Desertification since they entail significant Risk factors and need to be paid due attention for desert greening programs.

About 80 percent of Iran is arid and semi-arid and about 35 percent of this area is susceptible to Desertification hazard. Therefore Desertification assessment and identification of the most important criteria for the assessment of Risk and a basis for development of management plans is essential. This research was conducted in the semi-arid region of Agh-Band in the Golestan province, Iran with an area of 3062.5 km2 aiming at preparation of the Desertification hazard and Risk maps and development of various management plans to control the Desertification. In this study, the IMDPA model and geomorphologic facies were used to evaluate the Desertification hazard. The work units (geomorphologic facies) were defined based on geology and land use maps, satellite images and field surveys. The Risk map was developed with a combination of Desertification hazard intensity and hazard elements and degree of vulnerability maps using the total Risk equation. Desertification management plan was developed based on four management strategies including: no plan, maintains the status quo, avoid the Risk and implement the control measures. The results indicated that soil and vegetation criteria with magnitudes of 2.67 and 2.54 fall into sever Desertification category (III) and other criteria are within medium class (II). The average value of degree of Desertification in the study area was 2.03 (class II).

In many countries, studies to determine the severity of Desertification and providing land plans to implement Desertification. One of the models is modified MEDALUS or Iranian model (IMDPA), has been used in present research in order to investigate Desertification situation in the Tashk region of Fars province. In this research, the modified IMDPA model used with emphasis on the water, soil and agricultural indexes, and indicators for each criterion has been considered in different value. The qualitative values of Desertification indexes placed in four classes as, low, moderate sever and very sever. Among evaluated indexes, Irrigation system and drop level of groundwater have the most effects on Desertification with numerical values 4 and 3.7 respectively. In the other indexes, crop yield and SAR of water have the lowest effects on regional Desertification with numerical value 1 and 1.5 reactively. Analysis of result showed that the intensity of Desertification obtained 2.54 on the entire of region based on 3 indexes and in the base of modified IMDPA model, the regional Desertification intensity came to get medium.

In order to develop a clear and realistic Desertification control plan, identifying and evaluation of processes as well as causes and current status of Desertification are the basic needs of arid zones. In present study, the Desertification assessment of Incheh – broun area in Golestan province was performed using three indicators of ESAs model (soil quality, vegetation cover quality and climate quality). Therefore, the map of each indicator was obtained from the geometric mean of its layers. From the geometric mean of these indicators and by classification of obtained map, the Desertification sensitivity map of the study area (ESAI) was obtained. Finally, the study area was classified in three classes [no sensitive (7. 64%), fragile (14. 41%) and critical (77. 95%)]. The results demonstrated that poor drainage, heavy texture of soil, poor vegetation cover, besides climatic factor are the most important factors of Desertification in the study area causing desert conditions. With regard to the results and in order to prevent the advance of Desertification processes, the biological and mechanical land improvement techniques such as plantation of species resistant to heavy and saline soils and construction of drainage in water logging lands are recommended.

Classification and provision of Desertification intensity map, as an efficient tool, has an important role in evaluation of environmental capability and prevention of Desertification and reclamation of degraded lands. Therefore, in this research vulnerability assessment of environmental issues to Desertification Risk has been assessed in Abozydabad region using Modify Numerical Taxonomy (MNT) model. Results show that MNT model has high ability to assess Desertification Risk and provision of Desertification intensity map. Weighted average of the quantitative value of Desertification intensity was estimated at 0.54 for all the study area (intense class of Desertification Risk). The obtained results show that %29.5 of the area has high vulnerability and %2.5 of the area has severe vulnerability to Desertification and %68 of the region has moderate vulnerability to Desertification. The obtained results provide better planning for Desertification minimizing in relation to development projects and the balance between development projects and environment can be possible according to priorities and vulnerability hazard zoning of the area.

Nowadays, Desertification as a great problem affects most of the countries in the world, especially developing countries. Desertification phenomenon that occurs in arid, semi-arid and dry semi-wet regions, will reduce the land potential. In this study MEDALUS model was applied for quantitative assessment of Desertification Risk with emphasis on five criterion in Shahroud-Bastam Basin, because of easy style and data accessibility and also compatible with the effective indices on land degradation. For this purpose, first, the study area was divided into five homogeneous units. Then, five criteria including soil quality, climate, vegetation, management, erosion and 13 indicators were used for quantitative evaluation of Desertification in homogeneous units. Index layers for each criterion were prepared using GIS. These indices were ranked in accordance with Modified MEDALUS model. The geometric mean was then calculated and map was produced for each criterion. Land degradation map of each homogeneous unit was prepared using the geometric mean criteria. Finally, from their combination, Desertification susceptibility map produced. According to the results, climatic and erosion criteria with an average weight of 1. 607 and 1. 467, had the most effectiveness on Desertification and vegetation with average weight of 1. 377 had the least effectiveness. As a results, from the total of study area, with area of 7737. 71 km2, 40% (3096. 311 km) is located in the C3 class or extreme critical erosion, that requiring more attention to implement Desertification control programs. Result of this research is a managing tool available for decision-making regarding the selection of priority areas in the fight against Desertification.

Extended abstract Introduction: The growing trend of Desertification is one of Iran's most serious environmental, economic, and social problems, making the identification of the Desertification processes and their causes and intensification an important and necessary task. Therefore, to provide a model for showing the intensity of Desertification and determining the most critical factors involved in Desertification and its prevention, it is necessary to select appropriate criteria and indices.Characterized by a dry climate, low rainfall, unfavorable soil conditions, unprincipled land-use change, and increased wind erosion, Sarakhs city is facing a critical Desertification crisis which has led to severe environmental problems as it is considered the center of wind erosion crisis. Thus, considering the critical environmental and human problems existing in Sarakhs and the strategic position of this city, this study sought to assess the severity of the Risk via the Iranian model IMDPA and calculate and prepare a Desertification Risk map of the region. To this end, all the criteria required by the model were evaluated. As the Desertification Risk maps and the effective indicators of the region's Desertification serve as a suitable and efficient tool for managing Desertification crises, the prioritization of the crisis management program and the type of programs will be determined. Methodology: The Iranian IMDPA method, the geometric mean of nine climatic criteria, and relevant indicators in terms of geology, vegetation, agriculture, water, soil, water and wind erosion, social and economic issues, urban and industrial development were used to assess the severity of Desertification. The scoring of criteria and indicators was performed in work units, which are the faces of subsistence. Risk assessment of Desertification was performed by combining the Risk map of Desertification Risk, hazardous elements, and the degree of environmental vulnerability using a global Risk equation. After identifying the Desertification Risk classes and the natural and human elements across them via expert opinions and field facts, the vulnerability classes of the elements were determined according to the type of class of the Risk severity. To calculate the quantitative value of environmental vulnerability, each element's hazard map and conditions were considered economically and ecologically. Elements at higher Risk were also vulnerable. This evaluation was based on the relevant executive departments' expert opinions according to the regional conditions, which can have different values ​​in different regions. Finally, the product of the Risk classes of Desertification (H) in the classes of hazardous elements (E) and the degree of vulnerability of the elements (V) in the GIS environment of the Risk classes (R) was determined. Results: Lithographic maps, physiography, land use, and satellite images were prepared and integrated with the GIS environment to achieve work units' maps. After combining the maps in the ArcGIS geographic information system environments version 10/2, work units were obtained to be reviewed and corrected. Moreover, land use maps, geology, and surface cover maps were located via Google Earth images to be further adapted to the landforms. Finally, three units, 22 brigades, and 67 geo-biophysical faces were separated in the study area. Based on the criteria's geometric mean and the characteristics of Desertification in the IMDPA model, the numerical value of each of the faces was estimated to be 3, indicating the severe intensity of Desertification in the region. In terms of zoning, the region was classified into low classes with an abundance rate of 0.6, medium classes with an abundance rate of 18.8, severe classes with an abundance rate of 6.9, and very intense classes with an abundance rate of 11.7.Among the factors involved in Desertification, wind erosion criteria, vegetation, agricultural and socio-economic factors had the most significant impact on the intensity of Desertification in the region with an average weight of 3.5. Moreover, the vulnerability and sensitivity of the phenomena showed that low-sensitivity elements covered more than 35% of the area, and sensitive middle-class elements covered more than 64% of the area. Also, the number of Risks was calculated and classified into four categories ranging from low to high via global Risk equation, with their frequency reported to be 11.97%, 26.53%, 46.24%, and 15.26%, respectively. In this regard, it was found that more than 60 percent of western and eastern Sarakhs were on a high and very high-Risk level in terms of Desertification. These areas were home to many agricultural lands. Discussion & Conclusions: According to the study's results, it was found that more than 80% of the whole study area was classified as severe and very severe in terms of Desertification. Furthermore, wind erosion, vegetation, agriculture, and socio-economic criteria had the most significant impact on the region's Desertification process, with their weight value reported to be 3.5 on average. In general, using the Iranian IMDPA model, which is compatible with Iran's climatic and environmental conditions, especially with the study area, helped assess the region's Desertification intensity. Also, considering the use of intensity maps and the existence of hazardous elements and environmental vulnerabilities, the application of the global Risk model indicated the possibility of the development of Desertification in the region. It could be argued that evaluation of hazardous elements, especially the human and economic ones, is a good practice to assess environmental vulnerabilities, a fact that this study attempted to apply appropriately. It should also be noted that a Desertification intensity map alone cannot be a helpful tool for providing a desert crisis management program. While the region could be at a high Risk of Desertification,  the Desertification Risk would not be significant due to the lack of endangered elements, and thus, it would not be a priority in the Desert Crisis Management Program. Therefore, in addition to the Desertification intensity map, the endangered and vulnerable elements' map is also of great importance. The novelty of this applied research lies in its assessment of the Desertification intensity and Risk.

Introduction: Desertification is one of the most significant process of land degradation in all the world, especially in arid and semi-arid regions. In the United Nations Convention to Combat Desertification report (1994), Desertification is land degradation in dry-lands, resulting from various factors, including both climatic variations and human activities. This process is always associated with soil degradation, pollution and reduction of water resources, vegetation and other biological resources in natural and ecological conditions. Therefore, determining the main factors of this process can be very effective in proper land management. This research was conducted with the aim of zoning sensitivity areas to the Desertification intensity based on ESAs model and providing management strategies based on scenario planning in Razavi Khorasan province. Materials and Methods: In this research, five criteria such as climatic quality, soil, vegetation, erosion and management (human activities), and 20 indicators such as soil texture, soil depth, rock fragment, parent Material, vegetation density, fire Risk, rainfall. drought, water and wind erosion, land use change, mining, livestock density in pasture, etc. were used. were used. Scoring and weighting of the indicators was done using a questionnaire and based on the expert opinions of specialists, executive managers and field experiments. The designed questionnaire included 21 questions, that classified in the form of 5 criteria of soil, climate, vegetation, erosion and management, which were distributed among the statistical population in two rounds. Management strategies and policies were also obtained in the Delphi method in the form of expert panels (brainstorming). Results and Discussion: The results showed that the vegetation criteria with indicators such as the reduction of vegetation, the increase in the Risk of fire in pastures and forests due to the continuous droughts of the past two decades and the increase in the intensity of wind and water erosion, with a value of 1. 419, has had the greatest value and importance in expansion the intensity of Desertification. After that, factors such as human activities (management), climate, erosion and soil respectively have had the greatest impact on the sensitivity areas to Desertification in Khorasan Razavi province. In terms of the critical situation, the high percentage of the areas in the northwestern regions such as Quchan and Chenaran township due to the impacts of drought, severe changes in land use and water has become Desertification. In the central, eastern and southern parts due to drought, land use changes, lack of optimal land management and wind erosion, main reason has been the expansion of Desertification. Besides that, all the townships of Khorasan Razavi province have fragile conditions. This issue can be considered as an important and serious warning for the future management of Khorasan Razavi province. Therefore, in order to provide effective ways to deal with the intensity of Desertification, based on the opinion of experts and specialists in the current research, by considering only the priority indicators of each of the criteria, the number of 10 cross matrix of the important indicators of each of the criteria, 20 scenarios, 6 strategies and more than 40 strategies were obtained. So that, by using the suggested strategies could be planned and managed according to regional and local conditions, to reduce the intensity of Desertification. Conclusions: The ESAs model uses four criteria of management, vegetation, soil quality and climate mainly to evaluate areas sensitive to Desertification. So that, in this research, due to the importance of the erosion (water and wind erosion), for zoning map of sensitivity areas to Desertification were used. In order to provide management plans (strategies and policy), to reduce and combat Desertification in Khorasan Razavi province, management strategies such as,-sustainable management of vegetation,-water resources management and watershed management,-soil management,-livestock management and reduction of environmental hazards caused by human activities,-education, promotion and culture and sustainable management. Therefore, in this research, only the important strategies and policy that can provide a comprehensive vision of land management in Khorasan Razavi province, were suggested.