فهرست مطالب mahmoud behrouzi

In this study, the quality of the treated wastewater of Kish Island, which is the main source of irrigation for the urban area of Kish, was evaluated. First, samples were taken from 12 water storage points and transferred to the water and wastewater laboratory of Tehran University. The samples were transferred to the Laboratory of Tehran University and the physicochemical parameters include pH, EC, BOD5, COD, TSS, TDS, SAR, phosphate and nitrate, Mg, Ca and Na were measured. The results showed that in green space irrigation tanks, the water is pH and EC are between 0.2 and 1.9, which is lower than the standard; 7 reservoirs including Marjan Park, Hangman, Cactus Pool, Convention Center Pool, Iran Pool, Bagh Rah and Golestan Park Pool have BOD higher than the standard, which is considered a biological hazard for the environment. TSS is higher than the standard in 7 reservoirs, which include Marjan Park, Hangman Park, Cactus Pool, Iran Pool, Bagh Rah and Golestan. According to international standards, the amount of phosphate in water reservoirs is high and requires its management, especially in sewage treatment plants. The highest SAR was in the convention center, North Water Treatment Plant and Golestan Park, but its level in Pavion, Marjan Park, Simorgh and Cactus was less than 4, indicating its desirability for irrigation. But the reservoirs of the convention center and the northern treatment plant require more management, because the long-term use of this wastewater can lead to salting of the soil of Kish Island.

This study aimed to assess the suitability of land for constructing an outdoor sports stadium in Ardebil Province, focusing on the climate.

Weather variables, such as mean temperature, snowfall, and rainfall, along with environmental factors, were considered. The evaluation utilized a combination of Multiple Attribute Decision Making (MADM), Fuzzy Analytic Network Process (FANP), and Geographic Information System (GIS). A separate layer was created for each variable and after determining their weights, overlaying the layers with fuzzing was used to identify optimal lands for sports facilities in Ardebil Province.

The findings indicated that snowy days and average temperature were the most significant factors influencing the selection of land for sports stadium construction in Ardebil Province with fuzzy degrees of 0.241 and 0.163, respectively. Among the environmental criteria, land slope and elevation were the most important factors for selecting land for sports stadium construction in Ardebil Province with fuzzy degrees of 0.294 and 0.166, respectively. The land suitability results revealed that areas in the northern half of Ardebil Province, particularly Moghan Plain, Garmi, Aslandoz, and Beile-Savar, were highly suitable for constructing a sports stadium.

Emissions of particulate matter from car exhaust, tire wear, engine lubricants and street fence wear contain heavy metals, which are dangerous for the urban ecosystem. However, most of the particles are deposited on the canopy and soil of plants, which are absorbed by them. Pollution-resistant species with a high capacity to absorb suspended particles can be used to remove suspended particles from the urban environment. For this reason, in this study, concentrations of heavy metals in the leaves and soil of tree species in Bandar Abbas were measured and evaluated. Also, species with the highest potential for adsorption of heavy metals were identified. 

First, three tree species including Azadirachta indica, Conocarpus and Prosopis juliflora were selected as the dominant plants in Bandar Abbas and in 30 points of the fields with 5 points of the non-polluted environment outside the city (control), and sampled from the surface soil and leaves of these species. After preparing and digesting the samples, the concentration of heavy metals (cadmium, manganese, zinc and lead) emitted from urban traffic was measured using atomic absorption spectrometry in soil and tree leaf samples. Next, the difference in heavy metal concentrations between tree species was analyzed by ANOVA and between soil and leaves and between urban and control environments was analyzed by t-student test. Then, to determine the tree species with high accumulation of heavy metals, two indices of heavy metal accumulation (BCF) and bioaccumulation index (MAI) were used.

The results showed that the pattern of heavy metals in soil and leaves of tree species was Mn> Zn> Pb> Cd. The maximum concentrations of heavy metals in the soil and leaves were detected in Conocarpus, Azadirachta indica and Prosopis juliflora, respectively. Spatially, the highest concentration of heavy metals in the sampling points was related to Imam Hossein Street. However, the minimum concentration of heavy metals was observed in the Persian Gulf Street. The concentrations of Mn and Pb in the soil of plant species were different and their differences were significant at 95% level, but the concentration of Cd and Zn was not different in the soil of tree species. Pb, Mn and Zn concentrations were not different in the shoots of the studied tree species and their differences were not significant at the 95% level. However, the concentration of Cd in the shoots of the species was different and the difference between the species was significant at the 95% level. There was a significant difference in the concentration of heavy metals between soil and leaves at 95 and 99%. Also, the concentration of heavy metals in soil and leaves between urban and control fields was significantly different at 95%. The pattern of the BCF index in all species was Zn> Pb> Mn> Cd and heavy metals had moderate accumulation for tree species. Bioaccumulation index (MAI) showed that Conocarpus had the highest adsorption potential of heavy metals and the lowest adsorption potential was observed in Prosopis juliflora.

Conocarpus, by absorbing pollutants from urban traffic, purifies the polluted air of Bandar Abbas; However, Prosopis juliflora, which is one of the migratory trees in the city of Bandar Abbas, with strong and deep roots, dries up the surface and groundwater of the region. On the other hand, its potential to absorb urban air pollutants is weak. Therefore, despite their resistance to drought and heat, Conocarpus trees have a high potential to purify urban pollution and can replace Prosopis juliflora.

Ardebil plain is one of the flood points that requires the understanding of the flood potential. In this study, the flooding potential of Ardebil plain was performed using environmental parameters, observations of flood points and lack of floods and prediction algorithms were made including random forest and logistics regression. Independent parameters include DEM, Slope, Aspect, Distance from waterway, distance from dam, runoff accumulation, land use, landforms and indexes Topographic Position Index (TPI), Modified Catchment Area (MCA), Terrain Ruggedness Index (TRI), Topographic Wetness Index (TWI) and Stream Power Index (SPI) Indices. The Roc-AUC assessment results showed that the RF and LR model were validated by 0.99 and 0.98, and it shows that random forest models and logistics regression have the ability to predict and prepare a flood sensitivity map in Ardebil plain. The output of parameters effective in flooding showed that the marginal areas located around the central plain of Ardabil have less flood-flooding potential than the central areas. The results also showed that by moving from the southwest of the plain to its northeast, the grade of floods increased. This increase in flooding potential around the main drainage of the plain is greater than elsewhere.

Controlling industrial pollution sources in order to protect the environment is one of the management strategies in the path of achieving sustainable development, which requires predicting the concentration of pollutants in a specific radius of the chimney and mathematical models can be similar. Air pollution is one of the most important environmental problems in industrial areas and its release from the chimney and its distribution in the atmosphere of any area causes serious damage to the ecosystem of adjacent lands. In point pollution sources such as chimneys of industries and refineries, the spread of pollutants depends on factors such as physicochemical properties of the emitted material, chimney characteristics, meteorological conditions and surface topology.
In the present study, in order to achieve this approach in the middle mountain plain of Tabriz, the concentration of pollutants emitted from 20 chimneys of Tabriz oil refinery with AERMOD model for a radius of 10 km was predicted. In this study, using meteorological data, land use layer, digital elevation model and chimney characteristics, distribution and concentration of pollutants from the chimneys of Tabriz oil refinery including SO2, NO2, CO and PM2.5 was predicted using the AERMOD model. The AERMOD model is a permanent state distribution model that can be used to determine the concentration of various pollutants in urban and suburban areas. The AERMOD model has two modules including AERMET and AERMAP. The AERMET module is related to the preparation of meteorological and land use data files and the AERMAP module is related to the characteristics of the chimney, pollutants and the digital elevation model. AERMET module data include wind direction and speed, cloud cover, relative humidity and surface air temperature (2 meters above the ground) in a period of one hour, which is in the range of meteorological data of Tabriz Synoptic Station in the interval Estimated time from 2010 to 2020. Using the information provided in the two modules, the distribution of pollutants from the chimneys were calculated using the AERMOD model.
Annual wind rose plot showed that the dominant wind is from the east and the first-degree wind is from the west. The results of the model prediction showed that the concentration of CO 8h was 0.5 to 20 ug/m3; The concentrations of SO2 and NO2 1h were between 5 and 100 ug/m3, and the concentration of PM2.5 24h was between 0.5 and 10 ug/m3, which were less than standard emit. East winds transfer pollutants to the northern of the Sahand, southwest of the oil refinery, and accumulate at altitudes of less than 1500 meters. The highest concentration of atmospheric pollutants is in Kheljan city in the southwest of Tabriz oil refinery and prevailing winds have caused the pollutants to move away from Tabriz plain and not have much impact on the environmental ecosystem of Tabriz plain. Pollutants under the influence of prevailing winds, have accumulated in the northern foothills of Sahand and in the southwestern part of Tabriz oil refinery and their maximum limit is in the range of 1450 to 1500 meters, but from this level (1500 m altitude) onwards, as the altitude of the place increases, the concentration of air pollutants decreases. Due to the establishment of the boundary layer, the maximum concentration of air pollutants is at an altitude of 1450 to 1500 meters in the southern foothills, from which the concentration of gases and suspended particles from the chimney is reduced.
In the mid-mountain plain of Tabriz, the concentration of pollutants leaving the chimneys of the oil refinery is less than the standard limit and does not have much effect on various ecologies and ecosystems. Due to the presence of prevailing east winds, the maximum concentration of gaseous pollutants and particulate matter in the northern foothills of Sahand and in the ambient air of Khaljan urban settlement and the wind has caused pollutants from the city of Tabriz, which is located east of the oil refinery. It is moving away and flowing to the southern mountains, and in the metropolis of Tabriz, these pollutants are very low.

In this research, patterning of rainstorm (more than 10 mm) was conducted by instability indices in Ahvaz. At first, rainfall data from 2000 to 2015 was extracted and statistically examined. Instability indices for rainy days were calculated by the Skew-T diagram. Then, patterning was done by using hierarchical clustering, Ward method, and Euclidean distance. As the sample, one day was selected from each cluster and was synoptically analyzed. The results revealed 60 rainstorms for the respective period. More rainstorms occurred in January and December. Autumn and winter had the most frequent days of rainstorm, while it did not occur in the summer. The results of classification divided rainstorms into 4 patterns and more days were in the fourth class, while the least was in the second class. In the second and fourth classes, instability indices were severe and could predict possible rainstorms, but the first and third classes couldn’t predict because synoptic systems caused the occurrence of the rainstorm. In the second and fourth classes, rainstorms were convectional. The synoptic analysis showed that every time rainstorm occurred in Ahvaz, a deep trough at 500 hPa was formed in the East Mediterranean and the area was in front of it. Also, at sea level pressure, a low-pressure system formed in Iraq and winds got humid by passing through the Persian Gulf and entered into the atmosphere of Ahvaz. Due to the unstable atmosphere, the air would rise to heights causing rainstorm.

The mangrove ecosystem in the coastal desert and sedimentary islands northwest of Qeshm Island off the coast of the Persian Gulf is exposed to industrial pollution, urban effluents and oil pollution. Considering the fact that pollution can affect the ecosystems, any increase in the concentration of metals such as cadmium, lead, zinc, and copper may damage coastal ecosystems. On the other hand, the role of mangrove (as a coastal ecosystem) in accumulating heavy metals can be identified by measuring its transfer coefficient. However, as the heavy metal contamination in Qeshm mangrove ecosystem has still remained unknown, this study sought to identify and evaluate heavy metal pollution in the mangrove ecosystem of the Qeshm coast and to examine the ability of contaminants to accumulate in mangrove by calculating their transfer rate.

At First, ten mangrove stations were identified using Google Earth images. Next, mangrove sediments and leaf were sampled six times in 2019, which were then were encoded in plastic bags and transferred to the laboratory. Finally, the concentrations of heavy metals including zinc, lead, copper, and cadmium were measured using an atomic absorption spectrometer. Moreover, indicators such as CF, BCF, MAI, PLI, RI, and mPELq were used to assess the pollution of mangrove ecosystem in Qeshm.

According to study’s results, the heavy metals’ pattern was found to be Pb> Zn> Cu> Cd in the mangrove forest ecosystem’s sediments and leaves. Furthermore, the maximum and minimum concentration of zinc metal in mangrove’s sediments and leaves were found in stations 1 and 9, respectively. Moreover, while the maximum concentration of lead and cadmium belonged to the coastal station 1, their minimum values were found stations 8 and 5, respectively, both of which are located in the inland sediments of the mangrove ecosystem. Also, the maximum and minimum copper concentrations were identified in stations 2 and 10, respectively.On the other hand, the investigation of Qeshm mangrove ecosystem’ pollution revealed that while cadmium and zinc metals had moderate pollution coefficients, lead and copper metals possessed significant pollution coefficients. Moreover, the accumulation of heavy metals in mangroves were more than 1 in cadmium. However, the amount varied from 0.9 to 1 in zinc, lead, and copper. In general, it could be argued that mangroves can store and accumulate heavy metals in their organs. On the other hand, the MAI index is higher in coastal areas than in sedimentary islands. In fact, while heavy metals are highly accumulated in coastal areas’ mangroves, they are much less accumulated in sedimentary islands. Also, the PLI value is over 1in the whole mangrove ecosystem of the Qeshm island, indicating the island’s polluted state, whose maximum and minimum values belong to the coastal areas and sedimentary islands, respectively. Furthermore, the analysis of ecological risk (RI index) suggested moderate and low ecological risks in coastal areas and sedimentary islands of the Qeshm mangrove ecosystem, respectively. Also, examining the potential hazard level’s coefficient in the Qeshm Mangroveforest ecosystem (mPELq) showed that coastal areas and sedimentary islands had moderate and low pollution risks, respectively.

this study investigated the heavy metal contamination, its accumulation rate, and its transfer from sediments to mangrove leaves. Metal pollution with pollution indices has been studied that cadmium and zinc in the mangrove ecosystem in the coastal desert and sedimentary islands in moderate pollution and lead and copper in the pollution category are significant; However, the transfer rate from sediments to mangrove was high, indicating the ability of the plant to purge the coastal desert ecosystem from pollution. On the other hand, the Ecological and environmental risk indices and the environmental risk probability index suggested low and moderate pollution risks in the mangrove. Generally, it could be said that according to the pollution indicators, the Qeshm island’s mangrove-covered northwestern coastal desert contains higher concentrations of metals than the island’s sedimentary inlands. However, due to the coarser texture of the sediments, and the extensive distribution of coastal mangrove roots, the heavy metals’ transfer rate from sediments to plant organs is higher in these coastal areas than in sedimentary islands, considering the fact that soft sediments in sedimentary islands tend to absorb and accumulate heavy metals. Therefore, the coastal areas of the Qeshm island can be classified within the low pollution category. As mangrove forests possesses a high power transferring contamination from bed sediments to their leaves, they can be used as a new method for purifying the habitats of coastal desert areas, wetlands, and bays.

The North-Caspian Sea Pattern (NCP) is one of the atmospheric phenomena that originates from the pressure fluctuation at the 500 hectopascals level between the North Sea and the Caspian Sea. For the North-Caspian Sea Pattern, a numerical index has been defined, which is calculated based on the geopotential height difference of 500 hectopascals between the North Sea and the Caspian Sea. After the numerical calculation of this index, the output number is positive or negative, and the output of the positive number indicates the negative phase and the output of the negative number indicates the positive phase of this index.

To investigate the relationship between the precipitations of Ardabil province with the North-Caspian Sea Pattern, first the average precipitation, temperature and relative humidity of Ardabil, Parsabad, Khalkhal and Meshgin-Shahr stations during 1987-2015 was prepared from the IRI Meteorological Organization.Then, the data of the North-Caspian Sea Pattern for the period of 1987 to 2005 were prepared and used from the climate research system of East Anglia University. In order to calculate the mentioned index until 2015, statistical equations were used and the numerical amount of NCP index was prepared for the years 1987 to 2015.Then the monthly, seasonal and annual relationship of the North-Caspian sea pattern with the parameters of precipitation, temperature and relative humidity of Iran during a period of 29 years (1987-2015) was investigated with Pearson correlation at 95 and 99% level. In order to model the relationship between precipitation and the NCP model, the forward perceptron artificial neural network model was used.

The results showed that the correlation between monthly, seasonal and annual precipitation in Ardabil with the NCP index is not significant, and relative humidity has no significant relationship with the NCP index, but the temperature in February and July had a significant relationship with the NCP index at the 95% level.The results also showed that the relationship between precipitation and NCP index in Khalkhal is more than Ardabil, which was significant in November and December as well as summer and autumn seasons and the annual average of their relationship was significant at the 95 and 99% level. In November and December (autumn season), the correlation coefficient of precipitation and NCP index was positive, which shows that the amount of precipitation increases as the NCP index becomes positive. The correlation between the NCP index and the precipitation of Mashgin-shahr in January and December was significant and positive at the 95% level. The highest correlation between precipitation and NCP index was observed in Pars-Abad, especially in autumn, and at the 99% level, their correlation was significant and positive; this means that with the positive NCP index, the amount of autumn precipitation in the Moghan Plain will also increase. In order to fit the best artificial neural network model to the data, a regression line was used, and in this model, the R coefficient was 0.98 for the test data, 0.98 for the validation, and as overall, for the mentioned neural network model, its coefficient was equal to 0.98%, which indicates the appropriate fit of the model in predicting the amount of autumn precipitation in Pars Abad.

Moghan Plain, which is located in a flat area, and Sablan Mountains and high altitudes do not have an effect on its climate, are the only Tele-connection patterns that determine its precipitation regime, and this is the reason why the relationship between autumn rains is positive and significant with the NCP index. The positive phase of the North-Caspian sea pattern has been associated with the high Mediterranean trough, so that the studied area is located in front of the trough and the transfer of moisture from the Mediterranean Sea, the Atlantic Ocean and the Black Sea has caused autumn rains in Parsabad. Therefore, in spite of the influence of ENSO and North Atlantic Oscillation patterns on the precipitation of Ardabil province, the North-Caspian Sea pattern also plays an important role in its autumn precipitation, especially in the Moghan plain.

To investigate the effects of dust particles on physiological and yield characteristics of grapevine cv. Bidaneh Safid, a field experiment in randomized complete block design (RCBD) was conducted on 40 plants at the Malayer Grape Research Station, Iran, during 2015-2017. The treatments comprised of: 1) artificial dust (4.3 micron, on average), 2) washing vine by well water, 3) washing vine by soluble-in-water dioctyle solution (dioctyl sulfosuccinate under the brand name dioctyl) one day after spraying artificial dust, 4) washing vine after the occurrence of natural dust storm in the region with no artificial dust applied, and 5) control, dust was not applied and after dust storm vines were not washed. Analysis of variance revealed that dioctyl and dust treatment had the highest and lowest yields of 12 and 4.5 kg/vine, respectively. In addition, dust particles significantly decreased fruit set (by 21.7% as compare to dioctyl treatment), berries per bunch (57 berries per bunch as compared to dioctyl treatment (82 berries/bunch)) and weight of bunch (85 g as compared to dioctyl which was 110 g). Moreover, dust had adverse effects on lengths of shoot (decrease up to 62 cm), leaf dry weight (1.28 to 1.39 g as compared to dioctyl treatment which ranged between 1.45 and 1.55 g) and photosynthetic pigments. (e.g. chlorophyll a reduced by 1.26 mg g-1). In conclusion, washing grapevine with dioctyl and water removed dust from surface of the leaves and dust could not damage the growth and yield of the grapevine.

Floods are environmental phenomena that are in the category of hydrological hazards, but to identify the cause and manage strategies to control them, other environmental sciences such as meteorology, watershed management, etc. must be utilized. Because atmospheric systems play a role in the occurrence of rainfall which in combination with topographic factors, surface topology, land use and morphology of catchments based on the slope and hydraulics of rivers and urban waterways cause flooding. Therefore, in studying the problem of floods, especially in residential areas, a combination of environmental sciences can play an important role in understanding the mechanism and development of urban floods. Also, computer models have been upgraded to simulate the behavior of urban floods. Their approach is based on the conversion of precipitation to runoff, which can be evaluated and validated with results. These models are trusted in estimating the volume and flow of runoff from the flood. The hydraulic behavior of urban floods can be simulated using hydrological models, and the SWMM model has many applications in this field. In this study, we tried to determine the hydraulic behavior of floods by recognizing the patterns of flood generating patterns and estimating the volume and flow of floods in drainage channels of Minab city. The results will be provided to urban planners to improve drainage channels and duct capacity.

In order to identify the weather patterns of floods in Minab, at first the meteorological parameters of the region during a period of 19 years (2000-2018) were prepared by the Meteorological Organization and atmospheric parameters including average annual temperature, minimum and maximum monthly average, 24-hour rainfall, number of monthly rainfall days and number of flood days (rainfall more than 30 mm per day) were presented in the table. Next, from the floods that occurred, two urban flood events were selected and the atmospheric meteorologists of that day at the level of 500 hPa and sea level pressure were extracted from the NCEP / NCAR data center website and mapped in ArcGIS software processing environment. SWMM model was used to estimate runoff caused by urban floods and to model the hydraulic behavior of flood flow in the surface water drainage network of Minab city; in such a way the first the model was calibrated and evaluated with the events of observational floods and after its verification, the outflow from urban sub-basins, water volume in drainage channels, flooding in canals and duct capacity were simulated in urban sub-basins of Minab.

Average annual temperature is 28.7 degrees Celsius and its maximum is in June and July with 38 degrees Celsius and its minimum in December with 19 degrees Celsius. Most of the rainfall in Minab plain occurs in November to March, which peaks in December with 22 mm. Heavy rains start in November and end in March, and in April, heavy rains have occurred once during these years, which has led to urban floods in Minab. In the first pattern, synoptic examination of flood days in Minab showed that the 500-hpa trough in Iran and the low pressure of the Persian Gulf caused floods. In the second model of flood generator, the cold system from Central Iran at the level of 500 hPa and the low pressure system of Iran caused floods on the shores of the Persian Gulf and especially the Minab plain. In this study, two events of rainfall (19/1/2014) and (11/3/2015) were used to calibrate the SWMM model. The third event of 11/12/2015 was used to evaluate the model and to analyze the results. The coefficient of flow and the square of the mean squared error were used. The simulated model is compared with the SWMM model and their differences are not significant, indicating that the model is able to estimate and simulate the hydrological parameters of urban floods. From 100 mm of rainfall in Minab urban area, about 195 million liters of water has been runoff, of which about 189.6 million liters have been wasted as floods.

The result of urban flood modeling in Minab showed that the densely populated areas of Minab city play an important role due to impermeability to urban floods and water retention. Since Hazara Castle sub-basin, Velayat Park, City Center and Sheikhabad do not have enough capacity to transfer runoff during floods. With these conditions, the results of this research can be provided to city planners and designers of surface water conduction systems and urban drainage networks of Minab.

one of the problems that threatens coastal ecology is the entry of urban wastewater into the sea by estuaries. Discharge of wastewater into the four estuaries of Bandar Abbas pollutes the coast of the Persian Gulf, which is a priority for the development of management strategies to reduce the risk of pollution. In order to achieve this approach, the present study measured the physicochemical parameters of water and heavy metals in the sediments of the four estuaries of Bandar Abbas, including Sooro, Goursoozan, Shilat and Nakhle Nakhoda estuaries during four seasons in 2019 and Evaluated by pollution indicators. The results showed that the concentrations of DO, BOD, COD, TSS, Cd, Zn, NO3, PO4, detergent and oils in the four estuaries of Bandar Abbas were higher than the environmental standard. The difference in temporal and spatial distribution of water quality pollutants was significant at the level of 95% and its maximum was in Goursoozan and in terms of time in summer, spring, autumn and winter, respectively. The average pattern of heavy metal concentration in the sediments was Zn> Cu> Pb> Cd which mean concentrations was 103.20, 52.55, 19.95 and 0.611 mg/kg, respectively. The maximum metals were in Goursoozan and the evaluation of metal in sediments with Igeo, CF, mdc and PLI indices showed that Cd, Cu and Pb in four estuaries of Bandar Abbas, in the category of moderate to severe pollution. High concentrations of heavy metals indicated the impact of human activities, including the discharge of wastewater into the estuary.

Desert dust is formed under the influence of special weather and environmental conditions in desert areas and enters the atmosphere. Local hurricanes caused by surface air instability, passing through dry deserts, remove silt and sand particles from the surface and enter the atmosphere. Desert dust physically, in addition to its ecological effects such as lung-heart disease, disruption of the physiological cycle of the plant and erosion of cultural-structural buildings, contains heavy metals that are deposited on the soil surface, water surface and canopy surfaces of plants which cause chemical changes and physiological damage to environmental ecosystems. Heavy metals are generally referred to as a group of metal elements which have a specific gravity greater than 6 g/cm3 and an atomic weight of more than 50 g. The heavy metals that are important from an environmental point of view include: cadmium, arsenic, cobalt, vanadium, zinc, mercury, iron, manganese, nickel, lead, chromium and copper, which are non-degradable in nature. Furthermore, long life expectancy of the heavy metals is also considered as a very important environmental pollutant. Due to the environmental effects of heavy metals on soils, the present study tries to identify the concentration of heavy metals in Khuzestan province. In addition to monitoring the concentration of heavy metals caused by desert dust at a height of 2 meters above the ground, the concentration of metals in surface soil rangelands were measured.

Several location on Khuzestan province were selected for carrying out the experiment which include the rangelands around the cities of Dezful, Shousha, Ahvaz, Abadan, Ramhormoz, Behbahan, Izeh and Shushtar.  A sediment trap was then installed in these selected locations at a height of 2 meters above the ground to trap the fine dusts after each dust storm. The collected fine dust is then transferred to the laboratory to measure the concentration of heavy metals. The heavy metals that were measured in atmospheric particulate matter included lead, zinc, cadmium and manganese.  Moreover, each time the concentration of heavy metals in the atmospheric fine dust deposited in the trap was measured; the soil of the rangeland ecosystem of the same field was also sampled and transferred to the laboratory for heavy metals measurement.  Finally, in order to evaluate and determine the severity of contamination of atmospheric fine dust and rangeland soil with heavy metals, Geo accumulation Index (Igeo) was used.

The results showed that the maximum Pb metal in atmospheric fine dust of Abadan is (40.3 mg / kg), Zn and cadmium in Ahvaz is (365 and 1.72 mg / kg) and manganese in Abadan is ((548 mg) in kilograms). The pattern of heavy metals in the fine dust and rangeland soils of the region was Mn> Zn> Pb> Cd. The maximum concentrations of Pb, Zn, Cd and Mn were observed in the rangeland soil of Abadan station with the mean of 140.3, 450.16, 0.81 and 561 mg / kg, respectively. The concentration of heavy metals in the atmospheric fine dust of the warm period of the year was higher than the cold period of the year. The results of heavy metal concentration in rangeland soil showed that heavy metals in rangeland soils in the west of Khuzestan province were more than its eastern regions and its maximum was in Abadan rangelands and its minimum was in Izeh.Pollution assessment also showed that the western regions of the province are in a very polluted category in terms of Pb, Zn and Cd; But the eastern regions of Khuzestan province were in a slightly polluted category. Therefore, the entry of desert dust into the region is the main reason for the increase and accumulation of heavy metals in the rangelands of western Khuzestan province.

According to the experiment done on different regions of Khuzestan provience, the desert dust that enters Khuzestan province contains high concentration of heavy metals which can lead to many environmental problems. Desert dust mostly enters Khuzestan from the west and settles in western parts of the country which reduce wind speed and affects its ecosystem negatively. Due to the fact that the concentration of heavy metals in atmospheric dust and soils of the western regions is higher than its eastern regions, it can be concluded that dust deposition is the main reason for the increase in heavy metals in the rangelands of western Khuzestan province.

To identify the physicochemical and atmospheric conditions of a dust storm at the Dezful station (As Dezful Regional Representative), at first the frequency of the dust storm phenomena was investigated at the Dezful station in Twenty years (1994 -2013). During three events on June 24, July 21, and July 28, 2018, dust samples were collected with sediment traps and physical condition was performed with X-ray diffraction device and chemical analysis of the elements and heavy metals detected by flame atomic absorption and dust particles were evaluated with the Igeo index. Also, the atmospheric circulation in the middle level of the atmosphere and sea level surface that led to a dust storm was identified by using ECMWF ERA-Interim meteorological data. The distribution of dust particles was detected with aerosol optic depth (AOD), and the pathway of dust particles was examined by the HYSPLIT model. The results represented that frequency of dust storm is an increasing trend which has led to a decrease in horizontal visibility in Dezful. The maximum of dust storm phenomena is in summer time and July; The minimum in the autumn time and January. The mean distribution of dust particles in Dezful showed that PM10 was dominant in the size of the silicate tissue. The elements of dominant were Mn, Zn, Pb, and Cd was 491, 311, 32.9, and 1.41 mg/kg respectively, which indicates moderate to severe contamination compared to the standard level. Among the soluble elements, Ca, K, Na, and Mg had the highest concentrations; the presence of these elements is evidence of their desert dust particles. Tracing and calculation of their backward pathway showed that the alluvial deposits of the Tigris and Euphrates in Iraq were its main focus.

In this study, the effect of climate change on time of wheat cultivation, duration of growth period was investigated in Ardabil region. For adaptation to the phenomenon of climate change, and was developed appropriate crop calendar for wheat cultivation in Ardebil. To achieve this approach, first the occurrence of climate change was analyzed by using statistical downscalling, and the output data of the CanESM2 model using SDSM software under the RCP 4.5 scenario, next the climate parameters of the maximum and minimum temperatures and precipitation were simulated for the future period (2040-2011). Then the time of wheat cultivation was determined according to two temperature and precipitation factors for the base and future periods. The results of calculation of length of growth were obtained using GDD index. Finally, an appropriate agronomic calendar for the future years was determined based on this indicator. The results showed that the temperature is increasing and the average annual temperature in Ardebil will increase from 9.2 to 10.2 ° C and precipitation will be reduced to 15 millimeters. Under the conditions of the future climate, length of Growth period will reduce 20 days relative to the basic period. The time of wheat cultivation will be postponed for 15 days and the suitable time of wheat cultivation will be in the second half of October.

Dust storm is one of the air pollutants in desert areas that have damaging effects on environmental ecosystems. This phenomenon usually happens when severe winds occur in arid areas which are accompanied by the ascent of dust particles to the upper layers of the atmosphere. HYSPLIT model can assist in detecting the path of dust entering the stations. In addition, synoptic patterns play an important role in the occurrence of dust storms; as the atmospheric low-pressure system with a pressure gradient causes dust storms in desert areas. Dust can cause physiological and morphological effects on the plant. The deposition of particles on the leaf surface reduces light and shades on the leaf, which reduces photosynthesis and chlorophyll and stomata conduction in the leaf which has a negative effect on plant growth. The purpose of this study was detection the origin of dust storms at Malayer Plain with the tracing and extraction of generation of synoptic patterns and its effects on vegetative and reproductive traits of grape varieties of white seedless variety.  At first, the dust codes were extracted in a 24-year period (1992 to 2015) and were monthly and annually analyzed. Then the sand rose was plotted by wind rose plot software. In order to identify the synoptic patterns of dust storms in Malayer plain the PCA (Principal Component Analysis) method was used. The HYSPLIT model was used to detect atmospheric dust. In the second part of this study, the effects of dust storms on Malayer plain vineyards were studied during 2015 and 2016 years. The treatments were 1) washing and 2) non-washing grapevine after event of dust storm. Then, chlorophylls a and b, relative water content, leaf fresh and dry weights, length of shoot and internode were measured. Moreover, reproductive traits such as fruit set, number of berry per cluster, weight of cluster, sugar berry and yield were measured.  A total of 459 dusty days were observed during the study period with an annual mean of 19. The statistical analysis indicated a considerable increase in dust storm frequencies in the study area. The total number of dusty days in June accounts for 18.4% of each year, followed by April (15.8%), and May (12.4%). According to sand rose study of Malayer plain, prevailing dust storm blew from West (16% all dust storm) and South (15%) during the year. In the dominant patterns over 500 hPa and sea level pressure, the NCEP/NCAR reanalysis data show that an upper trough over the eastern Mediterranean is reflected in lower surface and accompany with a low-pressure center over Saudi Arabia which associated with the high pressure in Siberia and extending towards the south-east during warm times. This condition led to occurrence of dust storm in Malyer plain. There are two main paths to transfer the dust to the study area: (a) NW-SE which dust particles are transported from the northwestern region of Iraq and eastern Syria (60%) and (b) S-N where the dust particles are transported from central regions of Iraq and an internal source in southwestern of Iran, Khuzestan province (30%) to the Malayer station. Dust particles by deposition on the leaf of the grapevine reduced the chlorophyll a and b, fruit set, cluster weight and grape yield compared to plants washed with water; but dust particles did not impact on length of shoot, relative water content, leaf fresh and dry weight of grapevine. Discussion and The increasing trend of temperature and drought led to disruption of soil and vegetation cover. Additionally, desertification and drought resulted from mistreatment of water resources and climate change contributes to increasing of dust storm sources in the Iraq and West of Iran. The main cause of dust storm events in the spring is the formation of a low-pressure system in the lower atmosphere of the west of Iran with a divergence in upper level of atmosphere (500 hPa) over the deserts of Syria, Iraq and western Iran. Al-Hawizeh/Al-Azim marshes are covered by fine sand which is regarded as the extension of the dust storm source areas in Iraq border. In West Asia, most of dust storm events can be classified into Summer Shomal and Frontal dust storms. Shomal dust storm occurs across Iraq, Kuwait, western part of Khuzestan plain and some parts of Arabian Peninsula. Results of present study showed that main dust storm sources of western parts of Iran are central to northern parts of Iraq, and Eastern and central parts of Iraq and Syria, western parts of Baghdad and dry Al-Howizeh/ Al-Azim marshes. The results revealed that Chlorophylls measures are an important tool to evaluate the effect of air pollutants on plants. Chlorophyll plays an important role in plant metabolism and the reductions in chlorophyll concentration correspond directly to the reduction in plant growth. This study showed that the reduction of grape yield was 13 percent in dusty treatment as compared to control one. It can be concluded that increase of dust load resulted in lower stigma pollen loads. Moreover, dust can form a blockage layer on the stigma which could prevent the germination of pollen grains on the stigma and consequently reduction of fruit set.

In this study, in order to trajectory of dust in Sanandaj, at First, the events of dust storm extracted from the meteorological data in the 24-year period (2013-1990 AD) and was statistically analyzed. Then, one dust events that happened in the warm half of year which Lasted for 10 days selected and dust particles in the atmosphere was trajectory using the model HYSPLIT. In order to investigate the events of dust storms in Sanandaj was used for macro-scale of science synoptic and mesoscale science dynamics. The results showes that the number of dust storms in Sanandaj ascending line and gets more events every year; peak of Dust storms happened in the spring and summer and in May month. Outputs of HYSPLIT Model showed that the dust storm, have entered to atmosphere from the deserts of Syria and northern Iraq and the desert of Saudi Arabia had no role in it. The dust particles at 500, 1000 and 1500 meter had a trajectory from Syria and northern Iraq. The study of 700 hpa geopotential and sea level pressure maps showed that lifting the middle levels of the atmosphere, causing create the ridge and the atmosphere of Iran, Syria and Iraq were under control of Subtropical high pressure (STHP) that causing stabilizing the atmosphere of these regions and this conditions caused create the low-pressure system in the Iran and rising the air.