مقالات رزومه دکتر ابوالفضل رنجبر فردویی

Dust storm is one of the desertification and land gegradation consequences especially in arid and hyper-arid regions of the world. Fine particles released from the Earth's surface can be released several kilometers and subsequently over long distances, sometimes even across continents. These particles play a key role in the Earth system by affecting the radiation balance as well as forest and ocean ecosystems. Weather is often considered as the main factor influencing the occurrence of dust storms. Dust storms have increased in recent years mainly due to continued droughts and global warming. Temperature is an important variable in climatilogy in terms of its direct effect on weather variables such as pressure, wind movement, cloud formation and precipitation. Based on previous studies, the increase in temperature along with the decrease in rainfall and the increase in wind speed provide the conditions for the creation of dust storms. In general, the review of the studies conducted in the field of evaluating dust changes and the effect of temperature parameters on it shows that it is possible to conduct these studies from different perspectives and methods. Therefore, it is necessary to find a comprehensive view on dust and factors affecting it by reviewing and evaluating the results of other studies so that the phenomenon can be controlled and managed. The number of dusty days in Khuzestan province is significant and has increased in recent years. The reason for that is its proximity to the great deserts of the neighboring countries. Therefore, this province is one of the challenging areas of the country in the field of dust management and control. The purpose of this study is to evaluate the trend of dust changes and the effect of temperature on this phenomenon. The results of this study help to better understand the phenomenon of dust in Khuzestan province.

In this research, three data groups were used including the monthly average temperature of 13 meteorological stations in the study area, the monthly average land surface temperature (LST), and the monthly average aerosol optical depth (AOD). First, the trend of dust changes was evaluated using the Mann-Kendall test. Then, the relationship between temperature parameters and dust was investigated using the correlation between the AOD in a buffer of 5 km around the selected stationwith temperature parameters including monthly average temperature and average monthly LST in buffers of 5, 10 and 20 km around the selected station.

The evaluation of the average changes in the buffer of 5 km around the selected stations showed that in the months of February, July, December and April, no increasing trend was observed in any of the stations and even in the month of April, there was a decreasing trend in two stations. The trend of AOD changes was increasing with a probability of more than 90% in the months of August, September and November in seven, March in five, October in four, January in three, May in two and June in one station. The correlation results of temperature parameters and AOD showed that a very strong correlation between average LST and AOD has occurred only in the three months of May, June and July in different buffers. There are the highest number of strong correlations in the months of May to August between temperature parameters and AOD. Also, the highest number of very weak correlations occurred in April, March, November, and December. The highest number of very weak and weak correlations are related to air temperature (85 and 47 numbers, respectively). This shows that LST is more important than temperature in evaluating changes in dust intensity in the study area.

According to the results of this research, it can be said that air temperature has a weak correlation with dust, and most of the strong and very strong correlations occurred with the average LST in different buffers, which shows that LST is more important than temperature in evaluating dust intensity changes in the study area. In general, evaluation and monitoring of dust changes can be effective in identifying new dust sources as well as evaluating wind erosion, dust control, and management activities. Therefore, it can be suggested that an online and up-to-date system based on remote sensing and artificial intelligence be designed and presented to evaluate and monitor dust changes. In this case, the management of the dust phenomenon in Iran will be more targeted and the dust sources can be identified faster. On the other hand, one should pay attention to the factors affecting these changes and evaluate their effect on dust.

In this study, drought was investigated on water use efficiency (WUE) in different climates and uses of Tehran province. To calculate the efficiency of water consumption, the products of Gross primary production (GPP), Evapotranspiration (ET) and Palmer drought severity index (PDSI) obtained from the MODIS meter are used. Then the trend of changes in the index of primary gross production, evaporation and transpiration, water consumption efficiency and drought in the period of 2001-2021 using linearity and Mann-Kendall and slope tests, and then the response of water consumption efficiency to drought in different climates and consumptions with Use. It was evaluated from correlation analysis. By dividing annual rainfall into potential evapotranspiration (PET), the Aridity index (AI) was calculated and climate classification was done with the help of this index. The results showed that the indices of evapotranspiration, primary gross production and drought increased by 81.15, 86.86, and 99.99% respectively, and the water consumption efficiency index decreased by 76.24% in this 20-year period. Is. These results were confirmed by the slope test. Examining the relationship between the efficiency of water consumption and drought in different climates and applications showed that in dry climates, agricultural land and bushland had a negative ratio of 91.86 and 78.93, respectively, and pasture consumption had a positive ratio of 51.96. Agricultural lands, pastures and bushland related to semi-arid climate have increased by 85.38, 66.22, and 64.27 percent, respectively, and forest use has decreased by 84.87 percent. In semi-humid climate, respectively, 47.53, 60.48, 73.41% of the study area has a positive relationship in the use of agriculture, pasture and shrub land, and 91.30% of the use of forests has a negative relationship. In the climate, the negative impact of drought has been in 66.04, 61.15 and 50.56 percent of agricultural, pasture and forestry lands. In general, according to the mentioned results, drought has had a negative effect on water consumption in Tehran province, and it can be said that the resistance of the ecosystem against drought is determined by our correlation between drought index and water consumption efficiency.

Maintaining soil structure and stability is essential, especially in arid and semi-arid regions with poor soil structural stability. Destruction of soil and its crust can cause wind erosion and desertification. The objective of this study was to investigate the effect of using hydrogel nanocomposite mulch on the stabilization of sand surfaces. A wind tunnel test was used to evaluate the erodibility of samples treated with different amounts of hydrogel nanocomposite. The compressive strength of the samples was measured by a manual penetrometer. The prepared nanocomposites were examined using scanning electron microscopy (FE-SEM), infrared spectroscopy (FTIR), and X-ray diffraction (XRD) images. The results of the wind tunnel showed that the addition of hydrogel nanocomposite to the samples improved the soil erosion rate by 100% at a speed of 15 m/s compared to the control sample. Bonding between sand particles by spraying hydrogel nanocomposites improves the erodibility of sand. Measurement of mechanical strength of treated samples after 30 days showed that the resistance of the crust increased with increasing the amount of nanocellulose in the composite, which can be expressed due to the increased surface area of the nanoparticle and the possibility of further bonding of the nanocomposite polymer bed with sand particles. While the crust diameter showed no significant difference with increasing concentration and the sample treated with nanocomposites containing 3% nanoparticles was thicker compared to other samples.

One of the new and unique sections, especially in internal studies, is the quantitative examination of unevenness. The scientific and quantitative study of topographic position has always been one of the topics that have received little attention in domestic research. So, classification and identification of different morphometrically distinct regions are necessary. Thus, the present study aims to classify landforms in the northwest of Fars province, Kharestan region and investigate its factors affecting. In this regard, the Topographic Position Index (TPI) method was used in the first stage to classify landforms, followed by the CORINE method to determine erosion risk classes. Additionally, Landsat 8 satellite images from June 2017 were used to determine the normalized differential vegetation index (NDVI). The next step was to determine the relationship between different types of landforms and terrestrial factors such as height, slope, slope direction, topographic wetness index (TWI), Terrain Ruggedness Index (TRI) and NDVI. Finally, the status of different landforms was determined based on erosion risk classes. Results showed ten different types of landforms existed within the study area. Small plains (1.18%) were the lowest in the study area, while waterways (27.71%) and high peaks (27.48%) were the highest. The TWI was significantly correlated with landform classes at 95% level. Most of the region (91.71%) had NDVI classes of 0.1 to 0.3. Stream and u-shaped valleys were found to have higher NDVI values. Real erosion risk was classified into three classes: low, medium, and high with areas of 31.14, 31.11, and 37.78%. There were 44, 57, and 59% erosion levels in the low, medium, and high erosion classes, respectively.

More than 40% of the global lands are covered by arid and semi-arid areas, a quarter of which is covered with dunes, On the hand, wind erosion contributes by approximately 60% to desertification. therefore, additives or stabilizers are used to control wind erosion and decrease its adverse consequences.Soil stabilization refers to process whereby a product is added to the soil to improve its properties. stabilizing agents are typically classified into traditional and non-traditional types. Hydrogel as a non- traditional stabilizer is a hydrophilic polymer with a three-dimensional network. In recent years, researchers have developed a series of polymers to be used for various purposes, including the enhancement of soil properties. In this regard, this study sought to investigate the applicability and effectiveness of co-acrylamide acrylic acid hydrogel and determine its optimal concentration as a stabilizer of sand surfaces. To achieve the optimal concentration, a completely random experiment design was performed in the SPSS environment with three repetitions for all three concentrations of 0.5, 1, and 2%.

Collected from the Siyazgeh desert in northern Isfahan province, Iran, the samples of sand dunes used in this study. To investigate the efficiency of the chemical additives used in this study on the sandy soil’s properties, the polymer was used at three levels (0.5, 1, and 2%) with 3 replications. Accordingly, metal trays with 100 × 30 × 2 cm dimensions were used to administer the wind erosion test and determine the threshold of friction velocity. Then, the control tray and the treatments were tested under different wind velocities (the comparison of the samples’ weight before and after the wind tunnel test showed a weight loss). Finally, the effect of polymers on anti-wind erosion ability was studied in terms of compressive strength, abrasion resistance, impact resistance, and crust diameter.

Determination of wind friction velocityThe effect of three different concentration solutions on the shear strength suggested that all three treatments were resistant to maximum wind velocity (15 m/s, duration time was 20 min) and they didn’t lose weight. On the other hand, the control treatment showed 5 m/s for the threshold of friction velocity.Treatments ResistanceThe results of variance analysis showed that there was a significant difference between the treatments (sig <0.05) and compressive strength in different concentrations, and that increased compared to the control sample. While treatment 3 had the highest resistance (1.61±0.18), no significant difference was found between treatments 1 and 2 (Figure 1).As shown in Figure 2, treatments 3 and 1 had the highest and lower resistance against the sanding (46.67±5.19 and 8.67±0.96), respectively.The samples treated with 2% polymer revealed the highest sheer resistance (5±0.56) (Figure 3). As shown in Figure 4, only treatment 3 was impact resistant.   As shown in Figure 5 most crust diameter revealed in the sample treated with 2% polymer (15.63±1.74).

Considering the results of this study, it could be argued that composite concentration plays a key role in the influence of polymer adsorption on the soil’s particles. on the other hand, it was found that the sand’s strength and stiffness increased with an increase in the concentration of the polymer solutions, which could be justified by an increase occurred in the interaction between sand particles and additive.

Soil erosion is the most important factor in damaging and decreasing the productivity of agricultural soils. Moreover, as the transfer of sediments rich in nutrients through the soil leads to soil erosion and in turn to the decrease in the dams’ reservoirs’ storage capacity, bringing about adverse economic and eco-environmental consequences such as damage to land resources and decrease in land productivity, soil erosion is regarded as a serious problem in the world. Therefore, estimation of the soil erosion risk is necessary for preserving agricultural lands and achieving sustainable management of watersheds.

This study investigated the potential and actual erosion risk in Kharestan region, using CIRINE model together with GIS and RS. The parameters are presented as four separate indices. The model consists of the following steps. First, soil texture, depth, and the percentage of stones and pebbles determine the soil’s erodibility map. Second, Fournier and Bagnouls-Gaussen aridity indices which are calculated based on meteorological data would be used to form the erosivity layer. Third, slope classes would be identified according to the DEM of the study area, and then the potential soil erosion risk (PSER) layer is produced through the overlaying of soil erodibility, erosivity, and slope layers. Fourth, the LULC layer is formed based on the Landsat ETM7 images. Finally, the LULC and the PSER layers are combined to identify the actual soil erosion risk (ASER).

The study’s findings indicated that there existed 5 types of soil textures in Kharestan region, including Silty clay, clay lomy, silty clay lomy, sandy lomy, and lomy. It was also found that 75.28% of the study area included clay silty (14.36%), clay loamy and silty loamy clay (60%), and 24.71% of the region comprised of sandy loam and loamy texture. Moreover, three classes were observed for the soil depth of the area, including over 75 cm (60.54%), 25-75 cm (5.92), and below 25 cm (33.53). The findings also indicated that 88.42% of the area was covered with over 10% pebbles, while the rest of the area comprised of below 10% pebbles (plains and hills). In terms of erodibility as a function of soil texture, depth, and percentage of pebbles, 39.24% of the study area was covered by highly erodible soils, while 32.26% of the area was covered by low and 28.48% of it was covered by moderately erodible soil, respectively. In total, about 68% of the study area was erodible. The Modified Fournier Index (MFI) was classified in two classes, the highest value of which was observed in the study area’s class 3, indicating a moderate rainfall. In addition, the Bagnouls-Gaussen Aridity index (BGI) was classified into two classes, with its highest value found in Class 3, suggesting the dryness of the area. Comprised of MFI and BGI, soil erosivity index showed that 60.47% of the region had been located in medium erosivity class and 39.55% of the area had been located in low erosivity class. In terms of potential soil erosion risk, 29.125% of the study area was located in low class, 29.8% in moderate class, and 41.7% in high class. The slope map extracted from the study areas’ DEM showed that 68.38 % of the area was located at slope class of below 15% and 31.62 % of the area was located at slope class of over 15%. The actual soil erosion risk was extracted from the overlap of the potential soil erosion risk and vegetation. Surface vegetation was classified into fully protected (8.71%) and unprotected areas (91.69%). The outcome was a map depicting non-erosion, and, low, moderate, and high actual soil erosion risk in the study area. In terms of actual soil erosion risk, 31.14% of the study area were found to be in low class, 31.11% in medium class, and 37.78% in high class areas. The areas high erosion risk areas within the potential erosion risk map were reduced from 41.07% to 37.78% in actual soil erosion risk map after overlapping the vegetation layer.

Soil erodibility depends primarily on the structural stability of the soil (and hence its resistance to particle detachment by rain-splash or runoff) and its ability to absorb rainfall. As soils with medium to fine texture have low infiltration rates, the are less transferred when exposed to high velocity of runoff water. Moreover, in shallow soils, the rate of erosion increases due to lower potentials for water holding water and higher overland flow. The study’s findings also indicated that the areas with moderate–high erosion risk are located in northern, southeastern, western, and northwestern parts of the region, where the soil and water preservation practices should be focused. Thus, protection and restoration of vegetation in the Kharestan is highly important for the preservation of water and water resources. In the southern, central, and eastern parts of the region, the slope is generally slight and the soil is shallow. However, due to the mountainous nature of the region and the low involvement of human activities, the erosion risks lie in low-class areas. Considering the application erodibility, erosivity, slope and surface coverage, the use of CORINE model for determining the potential and actual erosion risk maps could well show different erosion classes in Kharestan region. Moreover, the study’s findings confirm the application of the CORINE model in natural resource lands. The study suggested that together with GIS and RS techniques, the CORINE model possesses great potential for producing useful and inexpensive erosion risk information in Iran with low data and in relatively short time.

Vegetation is one of the essential factors in structure and function of terrestrial ecosystem and it is one of the principal loops in water-soil-plant-atmosphere continuum. Several studies have demonstrated that vegetation covers are sensitive to alteration of climatic, edaphic, topographic and human activities. Thus, alteration in vegetation and its relation with the mentioned factors are important of high importance. In order to investigation of vegetation changes and its effective factors, the current study was conducted in Kharestan region placed in Fars province, Iran. In this regard, the images obtained from ETM Landsat 7 (2000-2017) and meteorological data gained from local and 17 regional meteorological stations were used. Using these images, temporal and spatial changes NDVI and NDVI anomaly were studied. A supervised classification method was used to extract land use map. Finally, the relationship of NDVI with climatic, topographic and anthropogenic factors was investigated. Relationship between NDVI and climatic and topographic factors was estimated using GWR and OLS methods, respectively. Generally, temporal variations showed a slow increasing trend in NDVI value. NDVI anomaly was mostly negative before 2008 but it turned to positive after 2009. NDVI spatial distribution showed an increasing tendency from north toward center and continued to south-west of the study area. The study shows that the vegetation cover change was caused by both natural factors and human activities. NDVI increased in agricultural and pasture lands. Also, natural vegetation has been affected by climatic factors more than irrigated vegetation (agricultural and gardens). Furthermore, vegetation variation influenced by topographic factors likes height, slope and aspect. Also, with an altitude over than 2500 m, NDVI showed a decreasing trend, on slopes lower than 5° it increased. NDVI values in north and east directions were higher than in southern aspects. The overall trend indicates an increase in temperature and a decrease in precipitation during the study period. The maximum positive and negative correlation between mean annual precipitation and NDVI using ordinary least squares method were 0.93 and 0.83, respectively. Also the maximum negative and positive correlation between NDVI and temperature were 0.65 and 0.5, respectively. The highest local R2 values between NDVI with precipitation and temperature were 0.45 and 0.44, respectively, which was observed in the central parts of the region. According to the obtained results through the present study, it can be stated that environmental factors like precipitation, altitude, slope and aspect are the Influential factors controlling vegetation in Kharestan (Fars province, Iran).

Evapotranspiration is one of the most important parts of the water cycle (Boegh and Soegaard 2004). Precise prediction of actual evapotranspiration () is essential for various fields, such as agriculture, water resource management, irrigation planning and plant growth modeling. Therefore, accurate determination of actual evapotranspiration has always been a major concern of experts in these fields. Due to the limited number of weather stations and the fact that collecting ground information is both time consuming and expensive, remote sensing and satellite imagerycan be a suitable tool in determination of actual evapotranspiration (Brisco et al., 2014). Satellite productions are usually divided into images with low, medium and high spatial resolution (Rao et al., 2017). Surface energy balance is a method usually used in combination withremotely sensed spatial data for estimation. Information collected from various sources, such as remotely sensedimageries and meteorological data, are used in this method. The present studyinvestigatesspatial distribution on different scales (from field- to regional-) using remotely sensed imagerieswithdifferent spatial and temporal resolution. TheSurface Energy Balance System (SEBS) is one of the most important methods used for the estimation of in remotely sensed images (Ochege et al., 2019). This model needs thermal maps produced using satellite images. Daily maps produced with RS are usually very large, and their pixelsize is usually so large that it can provide the spatial diversity found in the basins with respect to the errors (Mahour et al., 2017).

In order to estimate the actual evapotranspirationin satellite images collected from Zayanderud basin,the effects of Co-Kriging downscaling of surface temperature (LST) were investigated in June 2017 using two different methods.To reach this aim, we first applied a co-kriging downscaling method to a low-power LST product collected from MODIS at 1000 meters. Then based on the results and using the SEBS system, the daily  was obtained from images with average spatial resolution (250 m).In the second method, map produced usinghigh resoultion satellite imageswas downscaled to medium resolution (250 m). For both methods, 250 m resolutionMODIS NDVI products were used as co-variables.Then, validation was performed using Landsat-8 imagery, and land surface temperature was extracted from its thermal bands. SEBS algorithm was used to determine in Landsat 8 30-meter resolutionimagery. Accuracy of measurements wasexamined based on a comparison between down scaledLST and maps (250 meterresolution).

In the present study, mean LST equals 3/312 K (SD = 1.74) and average daily equals 12.5 mm / day (SD = 0.86). In the downscaling phase, the relationship between LST parameters and and vegetation index(as a co-variable)was investigated.Moreover, to investigate the relation betweenhigh resolution variables and NDVI, we re-sampled LST and   variables from a 1000 mresolution to 250 mresolution.In250 mresolution, there is a negative linear relation (r=-0.85) between LST and NDVI, but the relation betweenand NDVI is positive (r = 0.80). Thus, lower LST (> 305k) indicates more vegetation (NDVI >0.3) inthe region, while higher LST results in lower NDVI or lack of vegetation. As a result, more vegetation can be observed in regions with higher(12 mm/day). Results indicated that the difference between average  downscaled-SEBS (12.56 mm/day) and reference  (13.11 mm/day) is negligible. The RMSE between the reference and the downscaled  equaled 1.66 mm/day (r = 0.73), and RMSE between the reference LST and the downscaled LST equaled4.36 K (r = 0.78). Thus,values obtained from two downscaling methods were similar, but the  obtained from downscaled LST showed a higher spatial variation. Therefore, LST has greatly influenced the production of maps using remotely sensing images, and Co-Kriging downscaling has been useful for providing daily  maps with intermediate spatial resolution.

Evapotranspiration downscaling using the co-kriging method is not significantly different from the SEBS product and the results are similar. The results of -SEBS method isalso acceptable, but the  derived from the SEBS algorithm is more variable due to the LST downscaling.

Iran is frequently exposed to local and synoptically dust storm due to the geographical location of Iran. In recent years, dust storm frequencies and intensities have been increased significantly in Iran and especially in Isfahan Province, seriously disrupting human life and affecting the quality of life. This phenomenon is particularly increased in the spring and summer. Climate factors play an important role in dust storms. In this research, spatiotemporal changes of climate factors and dust storms were studied. Therefore, we analyzed climate factors (precipitation, temperature, wind speed and humidity) and dust storms frequency during 1992 to 2016. Poisson regression model was used for statistical modeling of temporal and spatial variations of dust and climatic parameters. According to the models, there was conformity between the results and the predicted values throughout the months. In addition, the results showed that wind speed played a major role in the occurrence of dust storms and had the highest coefficient. The results also showed that most of the dusty days are in the spring and then in the eastern part of the province, which is related to the local centers in the eastern part of the province and summer winds.

Dust is considered as one of the most widespread air pollutants. The objective of the study was to analyze the effect of dust load on the leaf attributes of the nut pistachio tree (Pistacia vera L.) planted in Badrood region (Kashan, central Iran) with a relatively high aeolian dust pollution. Some leaf characteristics including specific leaf area (SLA), relative water content (RWC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), total chlorophyll content (TCC), total soluble sugars (TSS), ascorbic acid (AC) and air pollution tolerance (IPTI) indices were evaluated. Increasing of dust load led to aggravation of state of stress in most of the parameters studied. However, IPTI and AC indices were increased with increasing the dust load. Even though all studied traits were affected by the dust load but RWC, LNC, TCC were amongst those that were less affected and SLA, AC, IPTI, TSS and LPC were more influenced by different quantities of dust load. It may be concluded that the long-term exposer of the plant photosynthetic surfaces to dust particles leads to significant changes in biochemical and biophysical attributes, which can lead to a decrease in pistachio productivity.

Development of tourism activities in desert ecosystems is one of the important strategies for sustainable development in arid and semiarid regions that if proper planning can lead to the development of the economy and infrastructure. Improper management policies are effective directly and indirectly on the destruction of the natural environment and more severely on drylands and deserts. Therefore, eco-friendly policies can be preventing from land degradation. Ecotourism development in arid regions can act as a management strategy in line with the environment and also an alternative policy to combat land degradation, ecosystem survival and optimum utilization of nature. Maranjab area in addition to attractions such as the historic castle, with geomorphological and geological phenomena such as sand dunes, Salt Lake and various forms of wind process, including sites geotourism which is capable of absorbing tourism based nature at the national and regional levels, but has yet to find its place in the country in terms of natural tourism. In this regard, the present study with plan of scenarios of desert tourism development in the form of site selection of salt hotel and safari park can provide the solutions to comply with the conditions of arid ecosystems. Therefore, the principles of this study are basis on recognizing the potential and capacities of Maranjab area and planning and management of desert tourism in the form of developmental scenarios based on the location of safari park and salt hotel.

Maranjab area with the geographical position 51 degrees and 15 minutes to 52 degrees and 8 minutes of east longitude and 34 degrees and 35 minutes to 34 degrees and 5 minutes of north latitude, is located in the city's political boundaries of Aran and Bidgol in Isfahan province. The region covers an area of ​​256 763 hectares, with average elevation about 850 meters. Long-term average annual precipitation in the region is 111.4 mm, and July and January, respectively, with average temperatures of 33.25 and 3.51 degrees Celsius are the warmest and coldest months of the year.
The research is applied and its methodology is based on analysis of spatial and field data in ArcGIS software and analysis of questionnaire data in Expert Choice software. The research process includes the definition of proposed scenarios in the form of salt hotel and safari park, identify of criteria and indicators of each scenario individually and collecting their data, determination of criteria and indicators weight using questionnaires and prioritize them using Analytical Hierarchy Process model, preparation of weighted maps and integrate them according to their weight, and finally zoning of land suitability of study area and priority zones to land allocation for each scenario. Site selection of mentioned scenarios were conducted according to criteria of available, landscape, environmental protection and limitation (risks). By applying the obtained weights of AHP model on layers of criteria and indicators, their weighted maps were prepared. Combination of weighted layers was resulted to layers of land suitability of safari park and salt hotel that in order to determine the location of the suitable zones, the layers were classified into five priorities by natural breaks methods.

In the salt hotel scenario, criteria of available, landscape, environmental protection, limitation and raw materials (salt) were assessed that according to results of AHP model have the weights of 0.495, 0.234, 0.132, 0.094 and 0.044, respectively. Also, the weighted maps of salt hotel scenario showed that digital ranges of distance to roads from 0 to 0.2415, distance to tourism attractions from 0.0158 to 0.1305, distance from residential centers from 0 to 0.1002, landuse from 0 to 0.234, vegetation covers from 0 to 0.0529, geological formations from 0.001 to 0.0137, wind erosion condition from 0.0016 to 0.0135, possibility of surface moisture from 0 to 0.0948 and distance to salt mine from 0 to 0.044 are fluctuate.
In the safari park scenario, criteria of available, landscape, environmental protection, and limitation were evaluated that according to results of AHP model have the weights of 0.418, 0.326, 0.161, and 0.093, respectively. Also, the weighted maps of salt hotel scenario showed that digital ranges of distance to residential centers from 0 to 0.22005, distance to roads from 0 to 0.1299, distance to health centers from 0 to 0.0214, landuse from 0 to 0.2353, vegetation covers from 0 to 0.123, wind erosion condition from 0.002 to 0.0153, distance from marsh areas from 0 to 0.0626, distance from aqueducts from 0 to 0.0223 and distance from mines from 0 to 0.0084 are fluctuate.

final map of land suitability of desert tourism in the region Maranjab represented that the salt hotel scenario layer has weight range between 0.3208 and 0.8351 and the safari park scenario layer has weight range between 0.2294 and 0.8351. Also, according to land suitability maps, 959 and 45403 hectares (0.3745 and 17/6828 %) of Maranjab area have very suitable capability as the first priority for allocation to salt hotel and safari park, respectively. The first priority of salt hotel has an area over 345 hectares, which along with the second priority with area of 614 hectares are generally compliance with Erratic Island in Salt Lake. This compatibility is due to the access to roads, landscape, lack of surface moisture and numerous tourism attractions. The first priority of safari park has an area over 16910 hectares, which is generally matches on sandy areas and sand dunes of north of Aran Erg. This conformity is due to the relative proximity of these lands to road and high weight of sand dunes landuse.

The correct management in natural ecosystems is not possible without knowledge of the health in its sectors. Vegetation is the most significant sector in ecosystem that has important role in its health. Resilience is one of the defining features of health vegetation The term resilience was first introduced in the study of ecological systems and demonstrates the ability of the ecosystem to maintain its performance in the face of environmental disorders. A resilience-based system is not only equipped with a disorder adjustment mechanism but also has the potential to benefit from changes in a way that lead to creating an opportunity for development, innovation, and updating. Therefore, when a change occurs, the resilience provides the needed conditions for restarting and reorganization. If this goes beyond disturbing forces, the system will have the power to return to the maximum vegetation density with the least erosion effects, otherwise the system will be vulnerable to the change that was created and could already be controlled. This research was done in part of North east of South Khorasan province (arid climate) with the aim of quantifying vegetative resilience on behalf of ecosystem health in response to drought occurrences and long-term precipitation changes, as environmental disturbances. Therefore first, using daily precipitation data from 15 meteorological stations around the study area, their annual precipitation was extracted and was standardized by Standard Precipitation Index (SPI) over the course of thirty years (1986 - 2015). Then, the SPI index data in 15 stations were interpolated by ArcGIS software based on Inverse Distance Weighted (IDW) method and dry, wet and normal years was estimated in the study region for each year. On the other hand, from archive of satellite images of Landsat 5 and Landsat 7, an image was created for each year in study period, between 15 June and 15 July, with permanent coverage at the best of growth. Following the necessary corrections for satellite images, the average Transformed Normalized Difference Vegetation Index (TNDVI) was obtained of each image by ENVI software. Finally, effected of precipitation changes on mean TNDVI was assessed and vegetation resilience was stabilized whit selected of sever time period samples based on four effective parameters (Amplitude, Malleability, Damping and Hysteresis). Comparison of annual precipitation variations in the thirty-year time series (1986 -2015) indicated two approximate wet and dry periods in study area. The wet period is related to the first fourteen years of the time series (1986-1999) and the dry period is related to the last sixteen years (2000-2015). In this term, severe precipitation incidents with different intensities were occurred in the study area including one case of very intense precipitation (1986), one case of intense precipitation (1991) and two cases of moderate precipitation (1996 and 1992). Also, four drought incidents were occurred including one case of intense drought (2001) and three cases of moderate drought (1987, 2006 and 2008). All precipitations (wet years) are related to the first half and most droughts are related to the second half of the studied period. In this study for fixing of vegetation resilience in study area and for calculating of its parameters, In addition to the thirty-year time series selected sever time sections. in the whole study series (1986 - 2015), maximum of mean TNDVI (49.37 %) was in 1986 (reference), the lowest mean TNDVI (43.58%) was in 2010, The year effect of the decrease precipitation and drought, and mean TNDVI in 2015 was 44.28 %. Amount of parameters amplitude, malleability and damping are respectively 5.79, 0.7 and 5.09, and hysteresis was zero (%). The result of this case showed that the vegetation has moved towards the reference state (Resilience) but has not reached to amount of reference vegetation. The most specific cases for vegetation resilience happened from 1986 to 1996 (wet period) and 2003- 2009 time sector (dry period). In the first time section amount of amplitude and malleability were 0.64 %, damping was zero and hysteresis was 0.25%. The result of this case showed that not only the vegetation was returned to the reference state but also was increased to the reference (Cross reference).So despite the reduced rainfall and occurrence of sever occurrences of drought in dry period, hysteresis parameter (0.05 %) observed in 2003- 2009 time sector too that confirmed clearly vegetation health in study area whit dry climate. Awareness of the health status of the vegetation and its response to long-term precipitation changes and environmental disorders, such as drought occurrence, ensure the success of the managerial plans for renewable natural resources. The present study is the second study on quantifying the vegetation resilience and the first study under dry climatic conditions in Asia (an average annual precipitation of 160 mm) conducted in Iran by calculating four factors related to resilience, and is the first study that has presented the factor hysteresis in the calculations. Despite continuous of difficult condition, the native vegetation of the study area has been able to return the reference state not only by resolving the disorder relatively, but also it has experienced hysteresis stage. A set of quantitative calculations showed despite reduced annual precipitation and drought events, vegetation has been able to maintain its resilience, which indicates the health of the vegetation in the studied ecosystem. With the presence of such amazing protective and consistent mechanisms in the vegetation of arid regions, it is possible to maintain and restore these regions by proper managerial plans.

High temperature, high irradiance, low water vapour pressure, and lack of precipitation in most months characterize arid ecosystems. Under these conditions, trees such as pistachio suffer drought combined with salinity stress. In order to study the simultaneous effects of salinity and drought stresses on photosynthetic apparatus function in P. khinjuk, seedlings of the species were exposed to osmotic stress induced by a combination of salt and poly ethylene glycol (Ctrl (without any treatment), low osmotic stress (LOS), moderate osmotic stress (MOS) and high osmotic stress (HOS). Chlorophyll fluorescence yields were measured / calculated for the following parameters: F0, Fm, Fv, Fʹm, Fʹ0, Fʹm, Fʹv, Fs, F0 /Fm, Fv/ Fm, Fv/F0, Fʹv /Fʹm, &PhiPSII, ETR and Photoinhib-PSII%. A one way ANOWA showed that all the mentioned parameters were differently reacted to osmotic stress treatments without any visible symptoms of foliar phytotoxicity. The highest decrements or functional alterations in fluorescence parameters (in frame of defense mechanism or inactivation of photosynthetic apparatus) were observed at HOS.

Salinity is one of the major environmental stresses that adversely affect plant growth and metabolism. Salt stress affects plant physiology at both whole-plant and cellular levels through osmotic and ionic stress effects. In order to investigate the effect of different levels of salinity on photosynthetic pigment content and nutrient in Saltwort Plants (Seidlitzia rosmarinus L.)، Experiment was carried out in completely random design (CRD) with 5 replicates. Treatments were composed of: control، 0. 25، 0. 5، 0. 75 and 1% (of dry soil bed’s weight). Indicated results، revealed a strong and negative relationship between increasing salinity intensity and all of measured parameters related to photosynthetic pigments. Chlorophyll fluorescence parameters such as F0، Fm، Fv/Fm، qP and NPQ showed significant changes at high levels of salinity stress (≥0. 70% salt per weight of dried soil). Our results showed a competitive process among the measured nutrients ions. In conclusion، the saltwort (S. rosmarinus) plants tolerate salt stress through accumulating Na+ and Cl- ions different organs and the species is proposed for rehabilitation of saline soils.

Salinity is one of the major environmental stresses that adversely affects plant growth and metabolism. Salt stress affects plant physiology at both whole-plant and cellular levels through osmotic and ionic stress effects. In Iran، orchard crops such as almond are mainly confined to irrigated fields. Irrigated agricultural lands in arid regions، characterized by chronic drought، extreme temperatures، and scarce precipitation، induce accumulation of salt in soils following a combination of sustained evaporative and transpirational water losses. In order to evaluate of physio-biochemical response in almond trees to salinity stress، the present investigation was carried out. One-year old almond seedlings (Mamaei cultivar) were subjected to different salinity treatments: 3، 5، 7، and 10 dS. m-1). Characteristics of photosynthetic pigments (involving، Chl. a، Chl. b، Chl. (a + b) and CIS)، concentration of nutrient elements and some biochemical parameters were measured. Our study revealed a strong and negative relationship between increasing salinity intensity and most of the measured parameters related to photosynthetic pigments. Our results showed a competitive process among the measured nutrients ions (amongst Na+، Cl-، and K+، Ca2+) and soil salt content. In conclusion، the photosynthetic pigment traits، nutrient element contents، and biochemical parameters measured under NaCl treatments indicate that almond seedlings studied can be regarded as salt sensitive.