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Introduction Climate change is one of the greatest challenges of our time to achieve sustainable development. The dangers of global warming and climate change can be recognised and planned for, so efforts should be made to identify the consequences and methods of adaptation to reduce their impact, as trees and plants are sensitive to climate change, heat and moisture stress, and forest ecosystems are affected by these changes. Climate change is one of the greatest challenges of our time to achieve sustainable development. The threats of global warming and climate change can be identified and planned for, so efforts should be made to identify the consequences and methods of adaptation and reduce their impacts because the sensitivity of trees and plants to climate change, heat and moisture stress, forest ecosystems are affected by these changes. Forest degradation due to climate change is a global phenomenon affecting many tree species. One of the major challenges to Iran's natural resources is the degradation of oak forests. The increase in temperature in recent years has lengthened the growing season of Iranian oak, and due to the lack of rainfall, the intensity of water stress on this forest species has increased. Understanding the extent of climate change in the Zagros ecosystem based on standard indicators that show climate change can help managers and planners take action to adapt to conservation and restoration conditions.Materials and Methods In this study, based on the standard indicators established and updated by the World Meteorological Organization, the occurrence of climate change in six sites monitoring the decline of oak trees in Ilam Province, including Sarabeleh, Mala Siah and Dalab Strait, was detected in both north and south directions. The trend slope line, trend slope error and trend significance of the indices in the statistical range P value=0.05 were calculated using ClimPACT software in R program environment. The characteristics of heat, cold, combined, and precipitation indices such as day, number of occurrences, and continuity of the index in the nearest synoptic station to each site were identified, and daily data of minimum temperature, maximum temperature, and precipitation parameters were used between 1987 and 2019. The variations of each index were plotted and analyzed as graphs in the R software environment. Accordingly, the trend slope and significant indices affecting heat stress (hot temperature indices and cold-temperature indices) and water stress were calculated with the software ClimPACT in the R programme environment.Results and Discussion The results of the trend and significance of thermal indicators for climate change detection showed that of the 16 heat indices studied, in Ivan station, 11 indicators showed a significant trend of about 70% and in Ilam 9 indicators showed a significant trend of about 56%.The heat-based temperature indices, especially those based on maximum temperatures, showed a significant change towards warming, while those based on minimum temperatures showed no significant trend. The study of heat waves showed that the northern and northwestern regions of the province were subjected to several periods of heat waves, which occurred with greater frequency and continuity in the northwestern part of the province (Malah Siah and Dolab Strait sites) than in the northern part (Sarab sites) of the province, confirming the emergence of high mountain regions as a result of climate change. Cold-based temperature indices of 8 studied indices in Ivan-e-Sorchrove station, 7 indices were above 87% and Ilam 3 was about 38% the trend was significantThe cold-based temperature indices in Ivan West station show a significant change in the direction of a decrease of frost and cold and their persistence and warming, and in Ilam station the decrease of cold and warming of air after 2008 indicates a decrease of cold and warming. The results of the trend and significance of the combined indices for climate change detection in Ivan West station were 100% and in Ilam station 50% showed significant trend. The combined indices confirm climate change in terms of increase in air temperature due to increase in growing season and increase in trend of change in maximum temperature. The study of the trend and significance of ten precipitation indices related to the frequency and intensity of heavy rainfall and the length of dry and wet periods showed only one index in Ivan-e-West station, which was about 10%. The station Ilam did not show significant changes in the precipitation index.Conclusion It can be concluded that zagros vegetative region in Ilam province has experienced severe thermal changes during 1987-2019 and climate change in the north of Zagros vegetative region is a type of temperature increase that has been extended to the northwestern regions of this region since 2008. The results show that in deterioration sites, in addition to increasing temperature, some precipitation has increased. Therefore, it can be said that the occurrence of climate change phenomenon causes increasing temperature, occurrence of floods, emergence of droughts and creating dust phenomenon, especially from neighboring countries and intensifying it in the country, all of these factors are the starting factors of the decline of Oak Trees in Ilam province. What seems to be important is to take necessary measures to prevent and mitigate the effects of climate change. These two measures can be effective and useful in reducing the effects of flood severity and risk. Therefore, managers and planners of forest ecosystems should have adaptive strategies to climate change in order to maintain and revive their executive plans so that Zagros can survive as a forest ecosystem. Although the occurrence of climate change phenomenon is one of the most important factors of drought and deterioration of Zagros forests, conservation and restoration of oak forest ecosystems can help reduce greenhouse gas emissions and climate change.

Abstract Considering the presence of 274 dusty days in 2021 in Zabol city, Iran, the present study aimed to evaluate the feasibility of using treated sewage effluent (TSE) for dust mitigation with natural methods of increasing land cover. Hence, first of all, the identification of sewage treatment facilities along with the volume and chemical status was carried out and compared to the various national and international legislation. Then, field investigation on land use and land cover, along with literature review on dust origins, sand detachment areas, and sand corridors in the study area will be assisted for optimal area suggestion. Note that, in the present study it was assumed that the application of TSE for wetting the surface to vegetation restoration resulted in wind erosion control in critical foci. The results showed that, so far, a total of 39,000 m3/day could be treated, in the whole study area. The TSE volume calculated based on two scenarios consisting, (1) data obtained from the related organization, and (2) based the capacity of the wastewater plant is 2.8 and 5.1 mcm/year, respectively. Additionally, the study of TSE quality and its comparison to various regulation such as FAO, USEPA, INS, and CWQI indicated the applicability of transforming TSE to 14 km away from the WWT planet daily for rehabilitation of Hammon Hirmand through irrigation of T.stricta to increase the vegetation cover to above 30%.

Although most dust storms, especially those prevailing in Iran, are often regional in nature, But local centers dust, the dust belt and specifically in Iran, played a significant role. One of the origins of local dust in this belt is Yazd city and salt domes northeast of Ardakan. Understanding the characteristics of dust storms is important in terms of type, frequency, location and time of occurrence. Due to the dry climatic conditions and strong and erosive winds on it, the city of Yazd is faced with various dust events every year, which causes significant damage to the economic and biological resources of the city. In addition to climatic parameters and indicators, some indicators reveal that climate change can also affect the course of changes in dust occurrence. In addition to climatic parameters and indicators, some indicators reveal that climate change can also affect the process of change in the occurrence of dust in order to identify these indicators from the software ClimPACT is based on RClimDEX software and runs in R 2.10 software environment. In addition to identifying the trend of dust changes, the purpose of this study is to determine the importance of each factor affecting the occurrence of dust in Yazd. For this purpose, analysis and comparison of different functions of neural network, multilayer perceptron was used and finally the model with the least error rate and the highest correlation coefficient, as the optimal model to investigate the share of climatic factors affecting the occurrence of dust originating around and outside the station was estimated based on the optimal model. The occurrence of internal and external dust (dependent variable) was modeled and analyzed and the most important determining factors in the occurrence of internal and external dust were determined

Introduction: Water depletion in wetlands, due to both natural and unnatural reasons, leads to the extinction and death of living organisms. After successive droughts, if flooding and rehydration occur, their recovery is highly unlikely. According to the Ramsar Agreement, the area of Shadegan Wetland is 537731 hectares and includes freshwater area, tidal zone, Mousa creek, and marginal lands. The freshwater area of the wetland is about 164 thousand hectares based on the Landsat satellite image during flooding and is equivalent to 28% of the total area of the wetland. This wetland is extremely important due to various functions such as flood control, air conditioning, soil erosion control, plant and animal habitat, and providing livelihood. The purpose of this study is to monitor the trend of changes in the freshwater area of the wetland using satellite images and identify the factors affecting changes in its area.Material and methods: Landsat TM, ETM +, and OLI satellite data from 1998 to 2017 were used to monitor the water area of Shadegan Wetland. Various climatic, hydro-climatic, and water management factors were extracted for the study period in the whole watershed. The trend of changes and their relationship with changes in the wetland water area were investigated using the principal component analysis (PCA) method, and the factors that explained the highest variance of water changes were identified and analyzed.Results and discussion: The trend of changes in the water area of Shadegan Wetland was increasing. Data using KMO and Bartlett statistics showed that the studied elements were suitable for changes in water area based on factor analysis. The results of factor analysis showed that five factors played an important role in changing the water area of Shadegan Wetland. In total, five factors were able to explain 88.9% of the variance of the data; the first factor was the temperature, the area under cultivation, the number of earthen dams and drains entering the sugarcane, which explained approximately 36% of the variance. The second factor was the humidity of the basin which explained 15% of the variance. The third factor was the instant discharge’s drought that explained 14.9% of the total variance. The fourth factor was discharge and precipitation with 11.8%, and the fifth factor was wetland moisture, which explained 11.2% of the variance of water area changes.Conclusion: Wetlands that are situated at the foothills of watersheds are affected by the factors in the watershed. In total, five factors were able to explain 88.9% of the variance of the changes. In the first factor, apart from temperature, three factors that result from human activities were the most important: the area under cultivation due to the development of large irrigation projects, use of water sources of Jarahi River, which is the source of 90% of water input to the lagoon and numerous dams, dams upstream of the wetland that prevent the arrival of flood and seasonal runoff, and sugarcane drainage as inlet water to the wetland. In order to manage the wetland, reduction of human activities and utilization of water resources in order to provide the natural water of the wetland should be considered so that the wetland can continue as a living ecosystem.

Water resources management is essential in countries, such as Iran, with arid and semi-arid climates due to global climate change and population growth. Knowledge of hydrogeological droughts and effective factors on groundwater drawdown is essential in providing management solutions for these vital resources. Therefore, the purpose of this study was to analyze the trend of groundwater variations and assessment of groundwater shortage in the Karkheh Watershed using the SPEI, SDI and GRI drought indices in an eleven -year statistical period (2006-2017). The results indicated that in most of the study areas, there was a correlation between the SPEI and SDI indices. The mean values of the GRI index in the study area of Karkheh watershed area show weak drought for the Sanghar, Nahavand, Sahneh, Hersam, Khorramabad, Tuyserkan, Asadabad, Malayer, Biston-Dinavar, Mian Rahan and Hassanabad-Qala-e-Shian areas. A more severe drought with the drought indices of -1.08, -1.13, -1.21, -1.23, -1.25, -1.31 and -1.35 was determined for Chaghloundi, Kuhdasht, Kangavar, Islamabad Gharb, Ravansar-Sanjabi, Kermanshah and Mahidasht respectively. These indicates a decrease in the water level elevation and an increase in the depth to the groundwater in these areas. The GRI drought index is more visible during the ten-year statistical period in the east, west and center of the Karkheh Catchment Area; while in the last years of this period, the central areas of the catchment had been affected by more severe droughts, which may be confirmed by the SPI zoning map. Although in most cases climatic drought, and consequently hydrological drought had caused the depletion of groundwater level in the basin, the results of comparison between the two types of drought indicated the effectiveness of other factors such as exploitation of the groundwater resources. Therefore, it is necessary to establish an integrated management for the sustainability of groundwater resources, especially in the agricultural sector, as well as reforming the management of traditional groundwater abstraction systems, before meteorological droughts and subsequent surface water shortages affect groundwater levels.

Extreme rainfall as one of the rainfall effects is one of the most critical climatic phenomena that has many spatial and temporal changes. Knowledge of its potential in each climatic region requires a lot of planning, especially in water resource management. The aim of this study is to determine the temporal and spatial variations of Iranian rainfall during different periods. In order grid data of precipitation with spatial resolution of 15 × 15 were used for 50 years (1962-2011). Then, the data were divided into 5 periods of 10 years and for each of the periods, the spatial distribution of frequency, mean, coefficient of variation and trend were mapped and analyzed. Therefore, the best criteria for choosing days with extreme rainfall, the 95th percentile threshold, and covering 50 percent of the total area of the country with a continuation of at least two days is appropriate. The results of this study showed that the highest frequency and average rainfall in all periods were initially related to the Caspian coastline and then to the North-West and West parts, especially the western slopes of Zagros. Also, the results of the analysis of the periods showed that the third period (1360-1366) has the highest frequency of extreme precipitation events and the highest coefficient of variability (above 200%) is related to the first decade (1340-1349) in a zone with an area of 58.4%, the largest of which is found in the central and southeastern parts of the country.

Gavkhuni wetland has faced numerous changes in its dry and humid surface due to some climatic and human factors in recent decades. This study aims to investigate the role of drought in producing and intensifying dust phenomena in the center and surrounding areas of Gavkhuni wetland. The physical changes of the wetland are first determined using remote sensing and GIS techniques. Then, the number of days with dust is identified using data measured at selected synoptic stations. Results showed that the wetland had its highest moisture level about 89% of the surface of water in 1993, and then there was a gradual decline each year since 1993. It has been more dried so that the wetland water level was less than 10% in 2013 and has been completely dried from 2013 to 2019. The results of the Lancaster index indicate most of the sand dunes in this area have been activated during the study period. Correlation analysis for annual and seasonal dust days at stations around wetland do not show a significant relationship with wetland drying condition in most of the stations. It is statistically significant for Isfahan station in spring and summer at 1%, and in autumn at 5%. However, since the direction of the Isfahan station storms is from west to east in spring and autumn, and the Gavkhuni wetland is located in the east of Isfahan, the relationship cannot be accepted. This relationship is significant for Shahreza station in summer and Aghda station in autumn at a 5% level. The directions of dust storms are from east to west towards Shahreza in summer, and from west to east towards Aqda in autumn. Therefore, increasing the trend of dust production in these two regions and seasons, considering the positive and significant correlation coefficient could be due to the dry surfaces of wetland in recent years.

The study of the temperature mechanism and temperature advection along with the thickness layer and its effect on the rainfall level of an area is one of the most important subjects in the field of atmospheric science. The present study was carried out with the aim of studying the temperature advection and recognition of thickness layer in relation to spring rainfall in Iran. For this purpose, a daily rainfall database with a spatial resolution of 15 × 15 km2 was used in the period 1961–2013. After extraction of precipitation days, the corresponding pressure data was extracted using the programming capabilities in the Grades environment, and with the help of cluster analysis, representative days and spring weather patterns were identified in the Matlab environment. To determine the day of precipitation, three criteria of daily rainfall of 1 mm or more, minimum two-day continuity, and minimum 50% coverage were considered. Sea level pressure maps of 700 and 500 hPa were extracted along with temperature advection and thickness of the atmosphere. The results showed that five effective patterns were identified on Iran's spring general rainfall mechanism. The strongest amount of temperature advection from the Siberian high pressure occurred in the eastern and north-eastern parts of the country and reduced to the west and south of its intensity. Generally, from the east to the west and from the north to the south, there was a milder temperature advection during spring rainfalls in Iran. In addition, the most severe temperature advection occurred at sea level due to high-pressure thermal systems. At higher altitudes and higher levels, the temperature advection had a milder state than the sea level, and reduced the severity of the temperature advection due to the dynamic situation of the atmosphere, especially the blocking systemand Mediterranean deep trough.

Wetlands are an integral part of the semi-arid and arid ecosystems, which are inundated during major floodings and are transformed into sources of particulate matter during drought. This phase of their life cycle is very disturbing as they affect breathing in downwind areas and result in many pulmonary diseases. Thus their management is very challenging. As the Mansuriyeh Wetland (MW) is transformed into a dust source when dry, and threatens the City of Ahvaz with dust storms in the lean years, and this is mainly caused by an eradication of the vegetative corer, it was decided to survey the area when the MW was brimmed with floodwater. This was achieved benefiting from the images collected by the Landsat TM, ETM+ and DLI during the June of 1988 through the same month in 2017, and the rainfall data provided by the National Meteorological Organization. Analysis of the information was carried out in three steps: preprocessing, preprocessing and post preprocessing using the support vector machine (SVM) along with the ENVIs software. Likewise the image were classificed into the inundated areas the land covered with vegetation, water and the bare land. Truthfulness of the image was validated through Google Earth employing the total accuracy and the kappa procedures. The percentage of the area covered by each class was determined through the GIS zooning. The area contributing water to the MW was determined as its watershed, the rain-gauging network was plotted on the maps, and the mean annual precipitation of the entire watershed was calculated and drought occurrence and its intensity were determined using the standard precipitation index (SPI): the R2 for this item was 0.6. Therefore, variation of the MW as a dependent variable is related to the drought as an independent variable. Thus drought is 60% responsible for dust formation. Other variables, namely numerous small earth banks, oil well drilling installation and agricultural activities may also contribute to dust formation. Variations in the extent of the bare area and its relationship with the dust formation indicated that 80% of the MW had dried during the previous10 years. Moreover, up to 100% of the area had been entirely without a vegetative cover in some of those years. Salinity of a fine- grained soil, also made it a potential source of dust storms that invaded the Ahvaz Metropolis.

Statistical analysis shows that the long-term occurrence of dust Khuzestan province last 60 years has been faced with the phenomenon of dust. However, dust storms with coverage of more than 50 percent and minimum 2-day duration over the past two decades have become an uninvited guest. Two conditions for the occurrence of dust storms are: the presence of dust, the presence of substrates and the presence of fine particles with a small diameter and a large volume of dust forming the source; and the another synoptic-dynamic conditions as the driving force and the transfer of dust particles from the source regions to other areas. In this regard, the aim of this study is to analyze the general pattern of dust in Khuzestan province in the warm period of the year. For this purpose, data from 20 synoptic stations from the Meteorological Organization have been extracted. Then, by performing cluster analysis, identification of effective patterns on Khuzestan dust has been investigated. The results showed that five patterns were identified in determining the patterns of dust storms in the warm year, including 1) Gang low pressure thermal. 2) Gang Low-pressure, low-pressure Eastern Europe, high-pressure North-East Europe. 3) Gang Low pressure, high pressure in Europe. 4) The massive pressure of Europe, the high pressure of Kazakhstan. 5) Polar warhead high pressure, low pressure, Iceland low pressure. The results showed that the synchronous mechanisms of the dust occurrence in the first to fourth patterns, Gang low pressure thermal, which is formed during the hot season of the year with extreme warmth and heat in southern Asia, played a major role in the dust situation on Khuzestan. By placing high strength Azores in the middle of the atmosphere, the pressure difference conditions between the two high pressure and low-pressure centers have accelerated the flow velocity from higher levels to the lower levels of the atmosphere. Consequently, in conditions of lack of moisture on Khuzestan and through the passage of compressive systems from the ground and areas susceptible to dusty, dust was transported to the Khuzestan area.

In the past decades, some desert wetlands have become critical regions for dust production in the arid and semi-arid regions of the world. Accurate prediction of the number of dusty days (NDDs) in these areas is of great importance. The most popular method for predicting climatic and environmental variables is machine learning (ML). Although it has received more attention for spatial prediction, it has received less attention for the temporal prediction of these variables. This work is the first effort to predict NDDs in the major source of dust production in southeastern Iran using ML models and different feature selection (FS) techniques. For this purpose, monthly data of 21 predictor variables related to the study period (1988–2017) was used to predict the target variable (NDDs). The main aim was to evaluate the support vector machine (SVM), conditional inference random forest (CRF), and stochastic gradient boosting (SGB) models based on three FS algorithms, including Boruta, multivariate adaptive regression splines (MARS), and recursive feature elimination (RFE) techniques in predicting NDDs around the Hamoun wetlands. After analyzing the collinearity effect and removing the independent variables with a Tolerance

In this study, precipitation data for 483 synoptic stations, and the U&V component of wind and HGT data for 4 atmospheric levels were respectively obtained from IRIMO and NCEP/NCAR databases (1961–2013). The precipitation threshold of 1 mm and a minimum prevalence of 50% were the criteria based on which the prevalent precipitation of Iran was identified. Then, vorticity of days corresponding to prevalent winter precipitation was calculated and, by performing cluster analysis, the representative days of vorticity were specified. The results showed that prevalent winter precipitation vorticity in Iran is related to the vorticity patterns of low pressure of Mediterranean-low pressure of Persian Gulf dual-core, low pressure closed of central Iran-high pressure of East Europe, Ural low pressure-Middle East High pressure, Saudi Arabia low pressure-Europe high pressure, and high-pressure belt of Siberia-low pressure of central Iran. At the same time, the most intense vorticity occurred when the climate of Iran was influenced by a massive belt pattern of Siberian high pressure-low pressure of central Iran. However, at the time of prevalent winter precipitation in Iran, an intense vorticity is drawn with the direction of Northeast and Northwest from the center of Iraq to the south of Iran.