فصلنامه مطالعات جغرافیایی مناطق خشک
پیاپی 39 (بهار 1399)

In this research, in order to investigate the effect of short and long term observational data on the quality of predicting climate parameters, the LARS-WG6 statistical downscaling model is performed for EC-EARTH model and the optimistic scenario RCP4.5 and the pessimistic scenario RCP8.5. Also the HadGEM2-ES model with the optimistic scenario RCP2.6 and the moderate scenario RCP4.5 and the optimistic scenario RCP8. 5 are investigated. Forecasts are applied on the next three 20-year periods (2021-2040, 2041-2060, 2061-2061). Three daily statistical periods of the Drudzen Dam Synoptic Station including the 30-year period (1988-2017), the 20-year period (1998- 2017) and the 18-year period (1988-2005), were used. The 18-year period was determined by examining the 30-year trend. A fractal based procedure is employed for extracting a complete pattern of repeating weather events including rainfall, minimum and maximum temperatures. The modelchr(chr('39')39chr('39'))s capability in the simulation was measured according to the base period and the accuracy of the anticipations was evaluated using MAD, MSE and RMSE statistical tests. Studying the results clearly shows the effect of time scale changes on the accuracy of predictions. Accordingly the 20 year time period showed the least error, especially for the precipitation parameter. In general, it was revealed that this model predicts minimum and maximum temperatures with high accuracy and the rainfall prediction holds less accuracy. The prediction of models under different scenarios and different time intervals showed an increase in minimum and maximum temperatures. Moreover, the model indicates while the average annual precipitation increases in the coming years, the pattern of precipitation will change. In April, January and December, we will see an increase in precipitation and a decrease will be experienced in February.

Sand dunes are one of the most important and sensitive wind erosion susceptible landforms whose activity varies depending on the severity of the impact of various climatic and terrestrial factors. Long-term monitoring of these factors, along with the mobility status of sand sands in different areas, can have a significant effect on reducing their adverse effects. One of the sensitive areas of wind erosion in northwest of Iran is sand dunes around Manjil city which is considered as a study area in the present study. The main objectives of this study are to investigate the effect of climatic conditions on the mobility of sand flows in this region as well as to predict the effects of climate change on the mobility of sand flows in Manjil. Hourly data related to climatic elements and dust events were used. The results showed that during the period of 1994-1996, the changes of dusty days and the mobility index of the sand flows in this downward region and the relationship between them were positive and significant. Also in the years 1995 to 1999, 2006 and 2008, Manjil has been in extreme danger of desertification and has declined sharply over time. The results also showed that on an annual scale, more than 90% of local winds were flowing at a speed of more than 11 m / s with the dominant northern direction in the study area. Based on the results of the sensitivity analysis, it was found that if the frequency of erosive winds or potential evapotranspiration decreased by at least 10% in the future, the Lancaster index would decrease from 249.9 to 194.6 and their fully active status would decrease. The situation will be more stable. It is also predicted that if these two climatic parameters are reduced by 30% simultaneously, the hills will remain active unless these factors are reduced to 40% simultaneously.

Today, risk management is an important part of the tasks of managers of organizations, institutions and geographical zones. This situation is more urgent in cities and for urban managers because cities are faced with different incidents due to concentration of resources and population, and urban managers seek to manage and control risk events in a way that minimizes damage and casualties. However, they usually do not achieve the desired results because of the numerous risks occurring in these zones, under the influence of different internal and external factors. However, most risk management research has been associated with the executive and economic projects, and its main purpose has been to prevent prolong processes, the increase of finished costs, waste of resources and position, and sometimes unfortunate events or loss of reputation. But with different events of recent years and the resulting financial damages and casualties, this has been on the agenda in cities. The sensitivity of these issues in urban areas is that any kind of risk that could lead to financial damages or casualties can lead to huge political as well as social crises that could cripple the sovereignty and political system. While this is considered quite common in the field of engineering and services, it has not yet been properly reflected in the urban and social contexts. Only experienced executives follow parts of the puzzle of systematic ways of identifying, analyzing, prioritizing and predicting urban risk mitigation measures relying on their own experiences. The process is intensified when there are major disasters and severe losses in which case little or no effect is observed despite high costs, because of hasty actions. This trend has also begun in Mashhad following the recent floods in Gonbad, Shiraz and Lorestan province. In fact, following these events, floods and rivers flooding that may not be of much importance in Mashhad have become the top priority for managers, with a great deal of costs spent in this regard. For this reason, the present study was conducted to systematically investigate the risk management conditions in this city and to determine the priorities while giving appropriate suggestions in this regard.

This applied study was carried out in a descriptive and analytical method. The required data were obtained through two researcher-made questionnaires. In the first stage, the main sample was asked to identify the main risk factors in urban areas, especially Mashhad. In the second stage, with 10% participation of the first sample, the factors collected in the first stage were prioritized and scored. The validity and reliability of the questionnaires used in this study were determined by experts in the field and was finally used in practice with the expertschr('39') approval and a score of 0.83 in the Cronbachchr('39')s alpha model. The population of the study consisted of all researchers and scholars working in the field of management, policy making and urban planning, of whom 200 individuals who were willing to participate in the study were selected and completed the questionnaires. Five-point Likert scale was also used to quantify responses. The collected data were evaluated through descriptive and inferential statistics using SPSS software, after which factors exacerbating and moderating urban risks were identified using risk prioritization technique and multi-criteria decision making method. Questionnaires were also administered along with face-to-face interviews.

The purpose of this study was to identify and prioritize some of the major risks of Mashhad metropolitan areas. To this end, a list of the risks of both human and natural groups was first prepared. Accordingly, a review of the related literature was carried out to complete and modify the list with the help of experts. After eliminating the unlikely risks or those with low effects, the priority number was calculated and identified for each risk area using expert opinions. The results showed 30 potential risks for Mashhad. After prioritizing human and natural risks, they were ranked by priority in a descending order through assigning a specific value to each in order to make policy making and planning of executive programs possible. Accordingly, risks which were given 20% of the highest scores were considered significant. In the meantime, risks with a probability rating of 8 and more were identified as critical hazards. According to these results, air pollution, rainfall and street runoff, as well as water pollution and shortage were ranked first to third with scores of 392, 192 and 180, respectively. Given that these events are quite different in terms of their occurrence and severity and fall into four categories of avoidance, transfer, control and acceptance in the urban risk management system, seven different strategies were proposed to prevent or reduce the damage caused by their occurrence. According to the financial and executive evaluations, empowerment of citizens and benefiting from the alternatives and options received the highest score among the suggested strategies. Accordingly, if the priorities identified in this study are taken into account and a systematic approach is followed, peoplechr('39')s trust and confidence in managers and administrators of urban affairs will be increased along with their participation in the process, while reducing damages of the potential risks. Overall, seven strategies were introduced in order of priority to deal with the prioritized risks in the present study the most prominent of which were empowerment of citizens and taking advantage of alternatives as well as options.

The circulation of dust suspended in the air is among the most significant environmental problems in the various regions of the world. However, the primary source of the dust present in the atmosphere is fine-grained particles and These tiny particles are more frequent in arid and semi-arid areas. The Tabas Masina Playa in Iran is one of the regions prone to dust production due to warm and dry climate and free of vegetation and on the other hand due to its exposure to the “Wind of 120 days”; and the Tabas Masina is one of the regions with high levels of dust where is exposed to the Sistsn, s“Wind of 120 days”. This research aims to study the role of this Playa on the dust of this region. For this purpose, sampling from the dusts of the dry lake of Tabas Masina and the Sistan Region was performed. These deposits were studied in terms of Granulometry, Morphoscopy, and Calcimetry. XRD tests revealed that Quartz and Calcite minerals were found in all samples. Also, the XRF test, the amounts of mineral compounds in all samples of Silica, Aluminum Oxide, Volatile Gases, and Calcium Oxide were higher in comparison to other mineral compounds.Based on these experiments the type of sediments and also mineral compounds were same in two areas. According to the Granulometry results of the deposits, about 59.6 percent was Fine Sand and considering that fine-grained particles can ascend to a considerable height and distance some kilometers from their origin, they have the potential to travel to the Sistan Region. Using the HYSPLIT Lagrangian model, dust particles direction was tracked. After routing dust particles, Tabas Masina Playa was identified as one of dust formation centers in Sistan plain.

Today along with the growing urban population, consumption rates of energy carriers and, especially, urban electricity are increasing. In long run, this issue can cause problems in provision of such urban infrastructure. Therefore, making necessary arrangements for optimal provision of urban electricity is a significant priority for urban planners. At the same time, solar energy is one of the main options facing major areas of Iran such as Sistan, mainly due to its unique features such as cleanliness and long-term cost-effectiveness. The region of Sistan with its important geographical situation including great sunshine and high temperature and its border location which is suitable for exporting electricity to its neighboring countries is in favorable conditions for such investment. The purpose of this study is to make a comparative evaluation on the six major cities of Sistan in terms of utility of solar panel deployment and the amount of the produced electricity. Hence, Metenorm7.2 software was used to collect climatic data and 4.6.3.PVSYST software was also used to simulate the final generation energy of the solar panels and to estimate its total revenue. The findings of the study indicate that among the studied cities in Sistan in terms of solar panels for electricity generation (assuming the establishment of 1 kW power plants), the city of Mohammad Abad with an annual energy production of 1644 kW and an area of 6.5 sq2, is in a better condition than other cities, assuming a constant inflation of 0.1 and a guaranteed purchase rate of 9317 Rials per kWh, generating a revenue of over 15 million Tomans/ unit/ year which in turn, can naturally a significant income for urban households

 Active tectonic studies are one of the most important topics in earth science and their results are widely used for assessing natural hazards and land use development and management plans in populated areas (Pedra et al., 2009, 220).Among these, geomorphic indices have been effective in assessing active teconic in large areas due to their high speed and accuracy (Clare & Pinter, 2002, 154).And are used to understand geomorphic processes, basin uplift velocity, and landform classification (Widget et al., 2017, 42).In tectonic active zones, the drainage network has shown the relationship between surface processes and structural changes (Delkailaw et al. 2006,244).Morphometric parameters are therefore highly efficient in identifying tectonic active zones (Chen et al., 2003, 115).Iran is tectonically active due to its continental convergence belt and 50% of recorded earthquakes occur in the Zagros Zone (Mirzai 1997; 40). The studied basins are located west of Kermanshah province in the Zagros Zone and the Zagros Fault, Zahab - Kandand Fault and Ghasr Shirin - Gilan Gharb Fault are in the range of these basins. These faults are mainly seismic.7.3 Richter Earthquake and Decades An earthquake measuring more than 5 Richter occurred in this area, due to the cities of Gilan West, Cradle, Karrand West, Ghasr Shirin, Sarpolzahab, Azg, Akhaliabad and Javanrood and many more. In the basins of these basins, the assessment of their active tectonic status seems necessary. Therefore, the purpose of this study is to evaluate the active tectonics and its classification in the studied basins.

The present research is based on descriptive-analytical, library methods and calculation of geomorphic and morphometric parameters.The research data include DEM SRTM symmetry, 1: 250000 geological map and 1: 50000 topographic maps.In this study, first using the DEM 30 m area of the catchment area and drainage network of the studied basins were extracted and then the topographic and morphometric characteristics of the basins were calculated.Then the geomorphic parameters of SL, Af, Bs and Hi were calculated (Table 1) and classified according to the classification of Qing et al. (2016) (Table 2).Then, the Active Tectonic Ratio Index (IRAT) was calculated based on (1).The morphometric parameters used in this study include Dd, R, Rh and Hd (Table 3).The degree of tectonic activity was calculated based on Morphometric Parameters (2) presented by Davies (1975) and based on the results, the tectonic activities of the region were divided into five zones with very low to very high activity. Finally, based on the findings of the study and considering the geological conditions of the studied basins, the active tectonic status is determined.

The AF parameter in the studied basins ranged from 23% to 63% (Table 2) and showed low tectonic activity in Gilan West, Zemkan, Flock and Zahab basins, Kafravar and Karrand basins with moderate tectonic activity and Sarpole and Qasr Shirin basins have high tectonic activity.Hypsometric integral parameter values in the studied basins ranged from 0.19 to 0.48, with moderate tectonic activity, low-tectonic activity, Gilan-west, Karand-west and Sar-e Pol basins with low tectonic activity and flock-catchment. And the palaces have very low tectonic activity.The values of SL index in the studied basins varied from 122 to 1569. Accordingly, the Kandar West Basin has moderate tectonic activity, Gilan West and Ghasr Shirin basins have high tectonic activity and Zakkan, Sarpol, Azaleh and Zabab basins have high tectonic activity. . The Bs index values in the studied basins varied from 0.83 to 4.70. According to this index, Qasr Shirin basin has high tectonic activity and other basins have high tectonic activity. IRAT index values in the western basins of Kermanshah province are between 3.25 to 4 and indicate high and very high tectonic activity in the studied basins. The drainage density parameter values of the studied basins are between 2.32 to 4.21 and these values indicate moderate to high tectonic activity. Roughness parameter values of the studied basins vary between 915 and 2169 m.Basins of Qasr Shirin and Karand West based on roughness values have low and moderate tectonic activity respectively and other basins have high tectonic activity.Parameter values of roughness ratio in the studied basins are between 0.016 to 0.059 and accordingly, Zahab basin has moderate tectonic activity and other basins have low tectonic activity.Roughness index in the studied bins show values between 2.73 to 9.02. Based on the values of this parameter, west west basin has moderate tectonic activity and other basins have high tectonic activity.

The results showed that the different lithological and structural features of the basins did not have significant effect on the final result of geomorphic and IRAT indexes and all basins had high to very high tectonic activity conditions.Results of morphometric indices and DAT index reflected the effects of basin lithological diversity on the final result.Also, contrary to the results of geomorphic indices, all basins are classified into two classes of tectonic activity based on morphometric indices of the studied basins are classified into three classes of moderate, high and very high tectonic activity. Finally, it can be stated that the studied basins in west of Kermanshah province are tectonically active based on the results of morphometric and geomorphic parameters. However, the tectonic activity of the basins due to the geological conditions has intensity and weakness and morphometric parameters are able to reflect lithological and structural conditions due to standardization.Therefore, it seems that morphometric parameters in watersheds with high lithological diversity are better able to evaluate active tectonic status.