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Abdolhamid Nazari, Hossein Sadin, Ogholgol Khorrami,
Volume 2, Issue 3 (10-2015)

Vulnerability to natural hazards is one of the most important issues of villages in Iran. Iran is listed in the first ten accident-prone countries in the world. It annually imposes many damages on villages through natural disasters such as earthquakes, floods, etc. To tackle the problem, an important attempt was applied during the recent decades is the policy of resettlement. The mentioned policy has been followed in forms of movement, integration and aggregation of villages. As spatial foundation and location of settlements are mostly based on natural environmental factors, then before any attempt, or before any dislocation of the villages, ecological potential of the new place needs to be evaluated. However, as dislocations resulted from unpredicted events such as flood are associated with emergency conditions and would be done very quickly; there is not enough time for evaluation before the action. In result, conducting such plans, unlike their positive impacts on service-delivery, cannot be quite welcomed due to ignoring the ecological and environmental factors which need to be considered before any actions. Therefore, such plans can create some negative consequences and be considered as non-successful plans.

       One of the projects that have been implemented in connection with this issue in Golestan province is dislocating and integrating flooded villages on Kalaleh County during 2001 to 2006. Based on the mentioned plan, twelve villages which were located at higher section of Gorgan Roud and were aggregated and located at a new site named “PishKamar”. These villages were flood-damaged. Such a site was urgently constructed based on a top-down approach, urban-based patterns and without considering the needs and ideas of stakeholders. So, such a plan needs to be evaluated and assessed against some normal and standard criteria. As such mistakes can be repeated elsewhere, recognizing the pros and cons of such plans would be a good guide and experience for the next projects. The present paper aims to evaluate the ecological potential, physical design of the site as well as measuring the levels of PishKamar site resident’s satisfaction.

      This study is a kind of the ex-post facto evaluation and its methodology is descriptive – analytical. To do that, we have considered a four-steps ecological potential of the site using Makhdom’s model. We also have used the 1:50000 topography maps, 1:250000 geological maps, 1:100000 land-use maps and 1:100000 soil fertility and capacity. All layers were transferred into ArcGIS environment, for more analysis. Data collection was based on surveying, interview and questionnaire. The statistical sample include 1350 households heads resided at the studied site, of them 200 persons were randomly selected for data collection purposes(According to Cochran AWT IMAGE  in the formula, standard deviation was 36%, test statistical was 1.96 and α was equal to 0.05). The results of the first stage of our study indicated that based on 330 primary integrated cells and overlaying the maps, there would exist 13 homogenous ecological units. In addition, a significant proportion of the Makhdom indicators used to assess indices was confirmed by chi-square test. Accordingly, 67% of cells in class I with good ecological potential and 8/28% of the cells in the appropriate ecological class II and only 2.4 percent were in class 3 to be inappropriate ecologically. Thus, of total 13 units, 11 units with an area equivalent to 127 hectares were classified as class I and II, and environmental units with an area of three hectares in third class were inappropriate. Therefore, the studied site was evaluated as a good site in terms of ecological conditions.

     In addition, evaluation of residents' satisfaction mapping site in terms of compliance with the ecological conditions and the physical texture design which was based on systemic approach of sustainable development indicators was revealed that the maximum satisfaction of residents was related to house orientation and strength of buildings, road network design and architecture patterns.But the dimensions of environmental issues including soil resistance as a result of landslides, climate harmony with the architecture and the wind direction has not completely been considered. Totally, of 11 evaluated criteria, people were satisfied with 6 of them and disappointed with another 5 criteria. It was confirmed by T-test.

Mostafa Karampour, Mohammad Saligheh, Meysam Toulabi Nejad, Zahra Zarei Choghabaki,
Volume 3, Issue 1 (4-2016)

In issues related to air pollution, the thickness of the boundary layer is known as the depth of the mixed layer because the pollution on the ground surface is mixed in this entire layer through turbulence processes. In most cases, the boundary of the area is clearly visible on big industrial cities. The depth of the mixed layer has an important effect in the concentration of air pollution which is dependent on the intensity and duration of solar radiation and wind speed. Usually after 2 to 3 hours from the time of maximum solar radiation, air temperature near the earth's surface reaches its maximum value. At this time convection of heat is formed in the air near the earth surface and transfers the heat from the surface to higher altitudes. These vertical movements will cause atmospheric turbulence and increase in instability. This is when the growth of the mixed layer reaches to its highest level. After sunset, night temperature inversion occurs near the surface. This temperature inversion is due to the rapid cooling of the Earth's surface. In such condition, the cold air layer is near the earth's surface and the warm air layer sits on top of it and air is in a stable condition.  As a result, the accumulation of contamination, if there are sources of pollutants, will increase in the earth's near-surface layer. If the conditions remain steady during the day, the mixed layer will not have much growth and as a result, contamination in the shallow layer near the surface of the Earth reduces solar radiation.

Each year, thousands of gaseous pollutants and particulate matter are emitted in the metropolitan area of Tehran and due to the geographical and climatic conditions of Tehran, temperature inversion phenomenon is not something unexpected. By formation of the inversion layer, these pollutants will remain near the earth's surface for a long time which in turn will be the cause of a lot of heart and respiratory problems. Therefore, identifying the characteristics of this layer on polluted days is of particular importance to the health of the residents of this city.

In this research, the study area is Tehran which is in the foothills of the southern Alborz and between longitudes 51 ° 2 'to 51 degrees 36' east and latitude 35 degrees 34 minutes and 35 degrees 50 minutes northern. The height of the northernmost point of this city is 1800 and up to 1200 meters in the center and 1050 meters in the south.

To conduct this research, inversion data including temperature, wind, atmospheric pressure and humidity and vertical navigation radiosonde data at the Mehrabad weather station from January to 29 December 2013, were taken from the Meteorological Organization of country. Then the statistics of daily vertical scroll of atmosphere above the Mehrabad synoptic station was received from the University of Wyoming. Also, the hourly data of air pollutants including gaseous pollutants CO, N2O, O3, SO2 and particulate matter (PM10) were prepared from the air quality control center (AQCC) for the stations Aghdasiyeh, Geophysics, Poonak, Rey and District 11.

After receiving information about the vertical scroll of the atmosphere in Mehrabad station, in order to have a closer examination of the vertical profiles of potential temperature changes in the lower atmosphere, using daily data from the radiosonde to obtain potential temperature changes in height were measured. Then, in order to identify the days with high pollution levels (the unhealthy condition for sensitive groups) and days with good conditions, so that all stations under study were the same, based on a standard index of air pollution Table 1 was developed. In the end, 4 days with critical inversion of potential temperature, including two polluted days (February 6th and August 16th) and two clean days (9 February and 5 June) were detected. Then according to the proposed method of Hefter, the approximate height of the boundary layer was calculated for these 4 days.

In this study, it was observed that the boundary layer height in contaminated cold season of the year reached 1,200 meters in the morning hours while in the afternoon in the cold samples, it grew to 1900 meters. In the warmer months based on the height of critical inversion layer in the selected days it reached more than 6,000 meters. In pure samples of warm and cold seasons, the boundary layer height had significant growth to the extent that in the cold sample of the year it reached to 2,100 meters in the morning and 2,600 meters in the afternoon. On June 5, which is intended to represent the clean and pure heating season, boundary layer height was of 5300 meters in the morning hours which shows a 4,000-meters increase in comparison to its polluted counterpart. The point to be noted is that since the active track of potential temperature can be considered as a measure of air stability, in the critical inversion, for the case of polluted samples of morning hours that were irradiated with inversion, active track of the potential temperature was very high in them. Thus on days with radiated inversion (polluted days) we can say that border of boundary layer was based on the inverted layer. Also the methods used in these types of inversions are more efficient for the determining height of the boundary layer.

Hamed Haidari, Dariush Yarahmadi , Mostafa Karampour,
Volume 7, Issue 3 (11-2020)

Dust phenomenon is one of the climatic fronts that is often formed in the dry and desert regions of the world, and is known as a natural hazard. Occurrence of walnuts causes dust, damage to the environment and the occurrence and exacerbation of respiratory, cardiac, air traffic and threats of tourism, agriculture and so on. Also, in the health section of the compounds in calcium dust, more than 2.5 g of it causes the appearance of kidney stones, and blood vessels. Iron causes swelling of the conjunctiva and retinal inflammation, as well as the syndrome. Magnesium causes depression, depression and dizziness of the individual. Short-term breathing of aluminum leads to coughing and irritation of the lungs and prolonged breathing causes damage to the lungs. In recent years, the identification of dust source areas has attracted the attention of researchers in numerous studies, and have introduced various areas around the world as the main source of generous production. The country of Iran, and in particular the Western and Southwestern logic of Iran, is constantly experiencing the phenomenon of dust and its problems. In the west of Iran, desert areas are located in the deserts of southern Iraq, Saudi Arabia and far away from Syria and North Africa. The geographic location of the southwestern part of Iran and its proximity to these deserts have led to a frequent occurrence of the phenomenon of dwarfs, which are different throughout the year.
In this research, two categories of data were used: the first group is data on climatic elements or unstable elements.
The annual climatic layers of the region were used for a 30-year statistical period of 2016- 2016. Measurement data on the temperature of surface temperature was obtained from a MODIS sensor in a 17-year statistical period (2000-2016). The second group of data layers and information on the ground factors or factors were stable. The layers of these variables included:
  1. The digital elevation layer of the area with a precision spacing of 30 meters from this layer was used as the elevation layer of the area.
    2. The slope of the region, in percent, which is the layer derivative of the digital elevation model and derived from the same specifications of the DEM layer.
    3. The surface layer of the surface layer that was taken from the MODIS surface coating product
    4. Layer of vegetation on the surface of the earth, which was also taken from the 1 kilogram MODIS vegetation cover
    5. Soil layer that was prepared by the country's water and soil organization
 The method of conducting analytical and statistical research in which the main objective is the determination of areas conducive to the formation or expansion of dust cores. In this regard, the establishment of land-based and climate databases is the first stage of work, after forming the required databases, the formation of information layers These data are in the GIS environment. In order to form these layers, the interpolated models in GIS were used and the optimal model was selected in such a way that less error values ​​were obtained. After forming the existing layers, we classified and weighed each layer based on the AHP weighting algorithm. Finally, due to the assigned weights, the overlaying of the weights of the layers in the GIS environment was obtained and finally a potential capability map of the formation of local dust collectors in Lorestan province was obtained.
 The rainfall factor is the most important and most important factor in determining the areas susceptible to becoming dusty. The weight of this factor in determining and identifying areas susceptible to dusty cores was equal to 239%. Vegetation factor, which was prepared using the NDVI indicator of the MODIS product, was the second factor in the development of dust-prone areas with a weight of 199.99. Relative humidity factor is the third factor or component that influences the determination of suitable areas to become the local focus of dust. The weight of this factor is equal to 0.15. The wind speed factor is in the fourth place in terms of determining the areas susceptible to dust. The relative weight of this factor is estimated at 116.0. As shown in Table 14, slope and elevation factors are the least important factors that can play a role in the production and development of dusty centers. The weight of these factors in identifying areas susceptible to formation of dusts is 0.024 and 032.2, 0 is detected. The calculated incompatibility index for this weighing is as high as 4.8, as shown in Table 15, which indicates that the contradiction between the offered weights of indices relative to each other is less than the allowed threshold (12).
 Neutbay expressed the highest concentration of areas susceptible to dust mites in the eastern region, especially the northeast of the province, which includes the cities of Azna and Aligudarz. There are also parts of this category in the southern regions of the study area, including the cities of Poldokhtar and Rumshagan. In the central regions of the province as well as in the northwest of the province including the Khorramabad, Delfan, Dynasty and Dorood districts this class is not observed. In the southern parts of the city of Kohdasht, small parts of the floor of the potential centers of dust are also observed. This flooring has the most risk of becoming a dusty focus. The power source of many of the province's dusty incidents can also be said to be areas where some of them are currently potential sources of dust. Since they have played a major role in the identification and detection of these areas, rainfall and vegetation cover, these areas are exactly in line with parts of the province, which, firstly, have a mean rainfall of less than 250 mm, and the density of vegetation is less than 2 / 0 (NDVI index), which represents a very poor vegetation and, in fact, a lack of viable vegetation. In terms of land use, these areas, or inferior land, or very rangelands, are very weak.

Dr Bromand Salahi, Mrs Mahnaz Saber, Dr Abbas Mofidi,
Volume 9, Issue 4 (3-2023)

evapotranspiration is one of the most important components in water balance and management. In this research, to evaluate the effects of climate change on the amount of potential evapotranspiration in the southern part of the Aras River Basin using the downscaled data of the GFDL-ESM2M model in the CORDEX dynamic downscale under the RCP8.5 scenario during the period of 2021-2050 and its comparison. It is treated with the values ​​of the base period (1985-2005). Data with a horizontal resolution of 22 x 22 km from the GFDL-ESM2M model were used in this research. The findings of the research showed that the minimum and maximum temperature and, accordingly, the ETp of the future period will increase compared to the base period in all six studied stations of Aras Basin (Ardebil, Ahar, Jolfa, Khoi, Mako and Pars-Abad). The value of this minimum temperature increase is estimated between 1.4 and 3.8 ºC and for the maximum temperature between 1.7 and 2.2ºC. The range of annual ETp increase varies from 133 mm to 189 mm. In the monthly ETp scale of all stations from January to July with an increase between 3.9 and 1.64 mm and from August to December with a decrease of 0.7 to 38.2 mm. Estimating the increase of ETp in the future period in the basin, especially in the months of spring, which is very important in terms of water demand, requires special attention to the possibility of this estimated increase in the planning of the water and energy sector.
Nazanin Salimi , Marzban Faramarzi, Dr Mohsen Tavakoli, Dr Hasan Fathizad,
Volume 10, Issue 3 (9-2023)

In recent years, groundwater discharge is more than recharge, resulting in a drop-down in groundwater levels. Rangeland and forest are considered the main recharge areas of groundwater, while the most uses of these resources are done in agricultural areas. The main goal of this research is to use machine learning algorithms including random forest and Shannon's entropy function to model groundwater resources in a semi-arid rangeland in western Iran. Therefore, the layers of slope degree, slope aspect, elevation, distance from the fault, the shape of the slope, distance from the waterway, distance from the road, rainfall, lithology, and land use were prepared. After determining the weight of the parameters using Shannon's entropy function and then determining their classes, the final map of the areas with the potential of groundwater resources was modeled from the combination of the weight of the parameters and their classes. In addition, R 3.5.1 software and the randomForest package were used to run the random forest (RF) model. In this research, k-fold cross-validation was used to validate the models. Moreover, the statistical indices of MAE, RMSE, and R2 were used to evaluate the efficiency of the RF model and Shannon's entropy for finding the potential of underground water resources. The results showed that the RF model with accuracy (RMSE: 3.41, MAE: 2.85, R² = 0.825) has higher accuracy than Shannon's entropy model with accuracy (R² = 0.727, RMSE: 4.36, MAE: 3.34). The findings of the random forest model showed that most of the studied area has medium potential (26954.2 ha) and a very small area (205.61 ha) has no groundwater potential. On the other hand, the results of Shannon's entropy model showed that most of the studied area has medium potential (24633.05 ha) and a very small area (1502.1 ha) has no groundwater potential.

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