Global changes in extremes of the climatic variables that have been observed in recent decades can only be accounted anthropogenic, as well as natural changes. Factors are considered, and under enhanced greenhouse gas forcing the frequency of some of these extreme events is likely to change (IPCC, 2007 Alexander et al., 2007). Folland et al. (2001) showed that in some regions both temperature and precipitation extremes have already shown amplified responses to changes in mean values. Extreme climatic events, such as heat waves, floods and droughts, can have strong impact on society and ecosystems and are thus important to study (Moberg and Jones, 2005). Climate change is characterized by variations of climatic variables both in mean and extremes values, as well as in the shape of their statistical distribution (Toreti and Desiato, 2008) and knowledge of climate extremes is important for everyday life and plays a critical role in the development and in the management of emergency situations. Studying climate change using climate extremes is rather complex, and can be tackled using a set of suitable indices describing the extremes of the climatic variables. The Expert Team on climate change detection, monitoring and indices, sponsored by WMO (World Meteorological Organization) Commission for Climatology (CCL) and the Climate Variability and Predictability project (CLIVAR), an international research program started in 1995 in the framework of the World Climate Research Programme, has developed a set of indices (Peterson et al., 2001) that represents a common guideline for regional analysis of climate. It is widely conceived that with the increase of temperature, the water cycling process will be accelerated, which will possibly result in the increase of precipitation amount and intensity. Wang et al. (2008), show that many outputs from Global Climate Models (GCMs) indicate the possibility of substantial increases in the frequency and magnitude of extreme daily precipitation. eneral circulation models (GCMs) are three-dimensional mathematical models based on principles of fluid dynamics, thermodynamics and radiative heat transfer. These are easily capable of simulating or forecasting present-future values of various climatic parameters. Output of GCMs can be used to analyze Extreme climate. For this study high quality time series data of key climate variables (daily rainfall totals and Maximum and minimum temperature) of 27 Synoptic stations were used across Iran from a network of meteorological stations in the country. In order to get a downscaled time series using a weather generator (LARS-WG), the daily precipitation output of HadCM3 GCM, SRES A2 and A1B scenario for 2011-2040 are estimated. The Nine selected precipitation indices of ETCCDMI[1] core climate indices are used to assess changes in precipitation extremes and monitor their trends in Iran in the standard-normal period 1961–1990 and future (2011-2030). Due to the purpose of this study, at first changes in extreme precipitation indices in the standard-normal period is evaluated and its results show annual maximum 1-day precipitation increased in many regions in the East of Iran. Simple measure of daily rainfall intensity (SDII), annual maximum consecutive 5-day precipitation, annual count of days with daily precipitation greater than 10mm (R10mm), annual count of days when rainfall is equal to or greater than 20 mm (R20mm) have increased in the central areas, regions in the north , north east and southern parts of Iran. Similar results are obtained for the R25mm index. The consecutive dry days (CDD) index has generally increased across the west areas, southwest, north, northwest and southeast of Iran and indices of consecutive wet days (CWD) decreased in these areas. Trends of extreme precipitation indices simulated by HadCM3 SRES A2 showing increases RX1Day in North West expect west Azerbaijan Province, central, southwest, north east and coasts of Caspian Sea. Similar results are obtained for the R5mm index expects northeast. There are mixed changes in R10mm across Iran, increasing in west, southwest, coasts of Caspian Sea, Hormozgan and Ardebil provinces, East Azerbaijan, Zanjan and Qazvin provinces. Similar results are obtained for the R20, 25 mm index in northeast, south of Caspian Sea, and some parts in western and central areas. Same as HadCM3 SRES A2 pattern there are mixed changes in R10mm across the region. Positive trends are seen in part of the Isfahan, Markazi, Kuhkilue , Lorestan, Ilam, Chaharmahaland Khozestan provinces and some part of Hormozgan and Kerman and some areas in north west. Similar results are obtained for the R20mm and R25mm index and in west of Yazd to north of Khozestan provinces have increased. Consecutive wet days (CWD) have increased over most of the west of Iran, Khorasn Razavi and Southern Khorasn provinces, In contrast consecutive dry days (CDD) index has generally increased in many parts of the region.
[1]. Expert Team on Climate Change Detection and Monitoring Indices
Tectonic geomorphology is part of Earth Sciences, which deal with study of the interaction of tectonic and geomorphology. In other words it studies the effective tectonic processes in forming and changing the landforms. Geomorphic and morphometric indicators are suitable tools to the morphotectonic analysis for different areas. These indicators are used as the base tool to identify and recognition of tectonic deformation or estimates of the relative instability of tectonic activity in a particular region. Some of geomorphic indicators has been widely used, then the results of research projects are used to obtain comprehensive information about active tectonics. Full assessment of contemporary tectonics and tectonic activities, especially the young tectonic and its hazards need to Full understanding of geomorphologic processes speed and made for this purpose, geomorphological methods play an important role in this context.
This research uses a descriptive-analytical approach, using library studies and aims at determininge the activity of Neotectonic in 7 Watersheds of Tehran metropolis (from west to east: Kan, Vesk, Farahzad, Darakeh, Velenjak, Darband and Darabad). In the first step, using topographic and geological maps of under the studied area, faults, drainage networks and watersheds are identified, then to evaluation the indicators of Mountain Front sinuosity (Smf), the main river sinuosity (S), the drainage watershed asymmetry (Af), rivers density index (D), hypsometric integral (HI), the ratio of the watershed shape (BS), the ratio of valley floor width to valley height (Vf), river longitudinal gradient index (SL) and Index active Tectonic(IAT) have been determined. Survey of these indicators by topographic and geologic maps and Google Earth images of the under studied area using software of Google Earth, Arc GIS and Global Mapper are derived and calculated. In the following, parameters and how they are calculated are given:
-Mountain Front sinuosity is the result from equation (1):
Smf = Lmf / Ls (1)
In the equation (1), Smf is index of sinuosity Mountain Front. Lmf is the front along the foothills and mountains of the specified slope failure and Ls: straight line along the front of the mountain.
- The main river sinuosity index is as follows: S = C / V. In this formula, S is main river sinuosity. C: along of the river. V: valley along of the straight line.
- Rivers density index, drainage density is obtained from the formula:
µ=
Li is length in kilometers of drainage Watershed, A is area in square kilometers, μ is total drainage watershed in terms of kilometers per square kilometer.
- Hypsometric integral is an indicator which represents the distribution of surface heights variation from equation (2) is obtained:
HI= H - Hmin / H max – H min (2)
In this equation Hi is hypsometric integral, Hmin and Hmax respectively are the minimum and maximum height and H is the height of watershed.
- The ratio of width to height of the valley floor is another geomorphologic parameters to investigate the tectonic forces in the region .This index is obtained from the equation (3):
VF = (3)
VF, represents the relationship of the valley floor width to valley height, VFW: the valley, Eld and Erd to the height of the left and right and Esc is valley floor elevation valley.
- The ratio of the area ratio of the area and the equation (4) is obtained:
BS= Bl / BW (4)
-BS; the shape of the watershed; Bl; length dividers watershed of water to the bottom of the watershed outlet and BW: width of the flat portion of the watershed.
-The longitudinal gradient index (SL) for a range of drainage path is calculated and determined by the relationship: SL = (ΔH / Δ L) * L. In this regard, SL: the longitudinal gradient index, ΔH: height difference between two points measured, ΔL: during the interval and L: total length of the specified channel to assess where the index to the highest point of the canal.
The classification provided for indicators Sl, Smf, Vf, Bs, Af by Homduni et al (2008), this indicator is obtained based on the amount of 1, 2, 3 classified in three classes. Index of active tectonic (Iat) Geomorphic indicators by means of different classes Calculated based on the value of (S /n) is divided into four classes, That the division are characterized by class 1 with very high activity Neotectonic, Class 2 with high Neotectonic activity, Class 3 with medium Neotectonic activities and and Class 4 with low Neotectonic activity. In this classification of Class1 have the highest and Class 3 have the lowest Neotectonic activities (Table11).
On the basis of Iat indicator Neotectonic activities in the under studied area were assessment and results were is in table (13). Based on the data in Table (13) , watersheds of Kan and Darband hava a high Neotectonic activities and located in Class 2 and watersheds of Vesk, Frahzad, Darakeh, Velenjak and Darabad have a medium Neotectonics activities and and located in Class 2, and Neotectonic activities are a high relative tectonic activity in all watersheds. Geomorphic indicators are reflecting activities in the metropolitan Tehran watersheds can say that tectonically active watershed has not yet reached stability and tectonic activity are relatively high. Geomorphologic indicators drainage watershed asymmetry, the main river sinuosity, the valley floor width to height ratio of density of rivers and valleys, structural geology and tectonic activity in the7watersheds of Tehran metropolis better show it.
The results show that Tehran metropolis Watersheds have a high relative tectonic activity in all watersheds, because of the proximity to the major faults (such as Mosha- Fasham and North Tehran faults) and minor faults, tectonic activity exists. Finally it can be stated that, due to the presence of multiple faults and background seismicity and tectonic activity in Tehran metropolis and its watersheds, occurrence of earthquakes in the study area is not unexpected and this issue requires serious consideration and management.
Climate is one of the important natural factors that affect all stages of life, particularly human exploitation. Selection of the type of clothing, housing, cultures, architecture, civil engineering, and settlements are influenced by climatic factors. It can be said that the climatic circumstances of the surface of the earth and atmospheric circulation patterns have an important role in shaping and organizing the environment (Alijani, 2009). In some cases, the normal weather conditions become abnormal and cause many damages, which are mostly catastrophes rooted in climatic changes, such as hail, frost, heat and cold waves, floods, storms and so on. Blizzard is one of the atmospheric phenomena, which happens as the result of snow combined with wind (15 meters per second), and low temperatures (below zero°C), and it causes severe losses.
Due to its special geographical location, Iran is placed in the transition region of the large-scale patterns of common tropospheric circulation, and is the intersectional place of the of extra-tropical and tropical circulation system. This feature along with its complex topography caused the land to have a considerable climatic diversity. The climatic diversity makes the various climatic phenomena to be observed with intensity, energy, and different frequencies, therefore, the climatic phenomena with high intensity always causes damage to natural resources and the human civilization. This undesirable phenomenon is called climatic risks. Since the West Azerbaijan Province is located in mountainous areas and high latitudes, the feature is triggered many climatic risks such as flood, hail, snow, snow storm, and so on. Therefore, snowstorm is one of such phenomena that have occurred every year or every few years due to the specific characteristics of the region and have caused damages in the fields of transportation, energy, livestock, closeness of schools and offices.
The purpose of this study is the statistical and synoptic analysis of snowstorm in west Azerbaijan province. Therefore, the data related to the present weather codes were collected during the period 1986 to 2009 from the National Meteorological Agency. The data related to the weather codes entered in Excel, and data related to the snowstorm were selected through Filter tool and isolation of codes related to the strong snowstorms (codes 37and39) and weak snowstorms (codes 36 and 38). Then the data related to the snowstorm was entered in SPSS, and the statistical analysis was performed. In the next step, three cases of the strong and common snowstorm (code 37 and 39) were selected for synoptic analysis. Then, the synoptic maps of the different layers of the atmosphere were selected as the samples for strong snowstorm for the days before the event of the phenomenon, the day of event, and the day after the event of the phenomenon by the using of the accuracy of 2.5 degrees from cdc.noaa.gov website. The study area has been selected in 10 to 80 degrees north latitude, and 15 to 90 degrees east longitude for identifying the patterns that affect West Azerbaijan Province. The data was received on wind speed and direction in digits from the National Center for Environmental Prediction. Then, the maps of the wind direction and speed were provided in Grads. Finally, the daily analysis and interpretation of pressure (500hPa at sea level), instability (700hPa level and the ground level), Earth's surface temperature, wind speed and direction maps for 700hPa level, and identification of patterns that have caused snowstorm in West Azerbaijan province were carried out. Statistical and synoptic analysis of snowstorm phenomenon in West Azerbaijan province during was performed in the period 1986 to 2009. To do this, using codes 36 to 39, which represent a variety of snowstorm (weak and strong), the frequency of snowstorm days on monthly and annual average, distribution of the snowstorm in the extracted stations, the frequency of strong snowstorms (codes 37and39), weak snowstorms (codes 36 and 38), all types of snowstorms (codes 36 to 39), and the frequency of storms in the station level were compared. Out of 322 snowstorms occurred during the period 1986 to 2009 in seven synoptic stations 108 have been determined as strong snowstorm and 214 as weak snowstorm. In order to analyze the synoptic snowstorm in West Azerbaijan province, in the first place, the strong snowstorms were identified, and then five of the strong and comprehensive storms were selected for the synoptic analysis. The snowstorms of choice are as follows: On 18 January 1986, on January 19, 2000, on February 7, 1992, on February 5, 1997, and on December 25, 1990.
For applying the study, pressure maps, Omega (700hp level at ground level), Earth's surface temperature, and wind speed and direction at 700hPa were analyzed, and patterns and conditions that are causing this phenomenon in the West Azerbaijan province were identified.
In this study, to perform statistical and synoptic analysis of snowstorm in Western Azerbaijan province, the statistical data were examined during the period 1986 to 2009 from 7 stations, and the results of the statistical analysis showed that:
• Out of a total 322 snowstorm event days of 7 synoptic stations during the period 1986 to 2009, 108 and 214 days were strong and weak snowstorms, respectively.
• Review the annual and monthly snowstorm during the study period showed that the 1992, 1997, and 1989 with a total of 69, 29, and 25 days, as well as the 1999, 2006 and 2007 with 0, 1, and 1 day have the most and the fewest days of snowstorm, respectively. The statistical analysis showed that the snowstorm phenomena happened in January, February, March, April, November, and December. January had the most and April had the fewest snowstorms with 119 and 3 days, respectively. February with 39 days, and April and November, with the number 0 and 1 had the most and the fewest days of strong and constant snowstorms.
• Distribution of the snowstorms in the stations indicated that out of the studied seven synoptic stations, which had a great impact on the synoptic situation of the region, topography, and height, Sardasht-Maku station had the most, and stations of Khoy, Mahabad, and Orumiyeh by having no snowstorms had the fewest days of snowstorm.
• The results of the maps of the different levels of the atmosphere and Earth’s surface in the days before the storm, event day and the day after the snowstorm were selected for the snowstorm pattern, which indicated that the snowstorm in the winter due to low compliance pressure formed in the earth's surface with synoptic patterns of middle levels of the atmosphere have provided the conditions for the event, in a way that among the sample cases of the strong snowstorms occurred in the West Azerbaijan Province two circulation patterns were involved in the formation of natural hazards: The Caspian Sea low pressure pattern- Eastern Europe high pressure pattern and the north of the Black Sea low pressure pattern.
The best path to development is the primary focus on the potentials and threats of the environment and accordingly efficient use of the land. In this regard, it has a closely relation between agricultural and rural development and natural resources. The type of land use is a main factor in soil erosion and sediment production in the watersheds. In this research, it has been studied and evaluated the soil erosion in the Aleshtar plain catchment with aim of developing agricultural exploitation.
This study is based on PSIAC model. The PSIAC method has been designed based on the estimating of sediment potential with 9 important effective factors contains surface of the earth, soil type, weather conditions, runoff conditions, topography, land cover, Land use, current erosion condition, slope of river erosion and sediment transportation in the soil erosion. In the process of this research using geographical information system (GIS), the mentioned data analyzed, integrated, and finally layers of information were prepared. Followed by extraction of units, erosion zoning of the studied area has been implemented.
The total area of the studied area is 80305 hectares and is located in the northern parts of Lorestan province (southwest of Iran) and geomorphologic features are almost mountainous and 39.65% of their area are mountains and hills. The maximum altitude is 3600 meters; the minimum is 1500 meters. and the average height of 2116 meters. Its climate type (based on De Marten method) is Mediterranean climatic pattern exists and the average annual rainfall is 506 mm. The Aleshtar City is the only urban center in the area but there are 208 villages. The economy of the settlements is based on agriculture (farming, gardening and animal husbandry).
Based on the findings of this research, 37.92% of the total land area of the basin is eroded (classes I, II, III). The land consists mainly of low slope and plain basin and is suitable for plantation (I). In this zone, 98 rural settlements (47.11%) are located. Relatively deep soils and flat are the features of these lands so the rate of erosion is low (II). 84 rural settlements (40.38%) are classified in this class. Shallow soils, these lands need to have conservation measures and can be managed under the operation of arable, rangeland, forest and resorts (III). 1 rural settlement (0.48%) is located in this class of erosion. 62.09% of the total basin land is located in the classes IV and V. A total of 25 rural settlements (12%) are located in this class. These lands under certain conditions can be planted; because erosion in the land is relatively high and the limitations in comparison with class III is more. Therefore they need more protection operations for exploitation. Also in these lands that are located in the high topography of the basin; erosion is extreme (Class V), which makes arable exploitation impossible.
Generally the land use in Aleshtar basin is faced to erosion limitation, so the control of the soil erosion and soil conservation and water resources management are essential. However, the locations of the most rural settlements were based on low to moderate erosion zones which indicates that the ancient has had a traditional preparatory thinking.
As a general recommendation, it can be said that in any location, including rural and urban settlements, along with the development of agricultural activities, attention to the erosion and zoning is essential.
Mountain systems have an important role on meteorological variations. Different components of the mountain affect the atmospheric parameters and have essential role in atmosphereic circulation. Garmesh wind is one of the most well-known phenomena that are related to mountain systems. In this research, mechanism of garmesh wind are identified using database of garmesh wind in the last 29 years and using remote sensing technology from 2005 to 2010.
To survey the Synoptic and dynamic conditions of atmospheric patterns in the Garmesh wind’s events in the region, SCDATA of several synoptic stations in Gilan province, including Rasht, Bandar Anzali, Astara and Jirandeh are used which had continuous long-term data in 1982-2010period After Identification of days with Garmesh wind, daily images of Modis sensor of terra and aqua satellites in visible band and 7-2-1 band are monitored for checking the cloudiness on the both sides (southern and northern slops) of Alborz mountains and data of Jirande station in southern slop of Alborz mountains are used for detecting atmospheric phenomena like precipitation and snowfall. Also for studying the synoptic and dynamic pattern of this phenomena, reanalysis data from NCEP/NCAR were used.
In this research, Based on the presence or absence of the atmospheric phenomenon (like rainfall and snowfall), three categories were identified. In the first category, Garmesh winds were happened in clear sky conditions and without any atmospheric phenomena on both side of mountain’s slope. In the second category, only cloudiness was seen at the time of the Garmesh wind. In the third category, precipitations (in this research, snowfall) were seen in southern slope of Alborz Mountains.
Statistical analysis of Garmesh wind in central plains of Gilan
Totally, Occurrence of Garmesh wind was 479 days in Rasht, during 1982-2010. The frequency of occurrence of this phenomena was in January, February, November and December and rarely, in September and June. Clouds that observed in the time of Garmesh wind were: Altocumulus (type 4), Cirrus, CirroCumulus.
Patterns of Garmesh wind mechanisms on western half of Alborz Mountain:
This category includes11 cases of total 47 studied cases. 29 January 2008 is an example of clear sky condition in the time of Garmesh wind. In this pattern, in the surface zonal extension of Mediterranean dynamical low pressure’s contours from west of Caspian to Gilan plain and at the same time formation of cold high pressure cell on Zagros mountains caused strong pressure gradient on southern coastal zone of Caspian Sea, As it led to the the increase of wind velocity in Rasht airport synoptic station from 11 kilometer per hour in 00 UTC to 36 kilometer per hour in 12 UTC. Dominance of warm core on southern Caspian versus dominance of cold surface air on Iran Plateau indicates adiabatic warming in northern slope of Alborz Mountains.
This category includes 34 cases of total 47 studied cases. Free of air mass’s patterns in the surface and conditions of atmospheric flows in low-troposphere that are similar to previous category, transition of height trough in mid-troposphere and high-troposphere can be name variant component verses previous category.
This category includes 2 cases of total 47 studied cases. At the same time, surface high pressure was on Iran Plateau and low pressure system was on Caspian Sea and also Gilan providence that caused the formation of Northerly stream and west-east stream to southern coastal zone of Caspian Sea and backward of Alborz Mountains like other patterns, snowfall occurred on southern slope of Alborz Mountains. Strong southern and south-western stream and strong positive vorticity on southern slope of Alborz Mountains by deep height trough in low-troposphere has an important role on intensification of vertical motions on lee ward of Alborz Mountains.
Garmesh wind is an atmospheric phenomenon that occurs as a result of interaction between atmospheric systems in synoptic scale and topography on back ward of mountain. In the other words, existence of Alborz Mountain’s as a great wall has an important role in the interaction between synoptic systems and formation of Garmesh wind.
Formation of Garmesh wind phenomena in Gilan province, is affected by extension of Siberian high pressure’s counters and sub-tropical high pressure on central of Iran Plateau and also existence of advection of pressure’s counter like sub-polar low pressure and or the Mediterranean Sea on north of Alborz mountains are required. Without any notification to origin of air masses, three categories has been observed based on existence or absence of Phenomena (in this research, sowfall)
In 700 and 500 hPa, Geopotential height patterns and relative vorticity field indicate that in the first category, wide parts of Iran is affected by high height and negative vortisity like low troposphere, during peak hours the wind. But in the second and third category (specially in third category ) existence of upper trough and easterly extension of trough caused to reduction of height and formation of strong positive vorticity in upper level and all over of air column in both south and north slopes of Alborz mountains.
Today urban livability reflects a powerful discourse in urban development and city design that is prevalent in urban planning literature suggests that there is an ideal relationship between the urban environment and the social life .On the one hand, the livability indicates the strong urban influence and attraction. On the other hand, the livability will further strengthen the urban connectivity and influence by attracting more investment, human and cultural resources. The livability of a city is closely related with a healthy and ecological city and sustainable urban development. This study aimed to measure the livability in the neighborhood of region(2) of Sanandaj city and research methodology is descriptive-analytical. A base map of the study area was prepared using Arc view Software. The region (2) is located in the central parts of the Sanandaj city.and the population of region is 239,965. The sample size was calculated using the formula Cochran. Therefore, 370 residents of neighborhood filled the questionnaire and expressed their viewpoint about the indicators of livability. A data collection method with respect to the merits of subject is Library and field method. The filled questionnaire by residents of different aspects of livability is measured. According to the Social features, facilities, geographic, economicfacilities and services available in the region , urban managers and experts have weighted the dimension and index of urban livability.The index of economic, social and environmental livability was calculated and the sum of these three dimensions is considered as total livability.To assess the livability of neighborhoods, data from filled questionnaires by people have been analyzed by the software GIS, SPSS and Excel. Using hot spots, three indicators and total livability of each neighborhood displayed.The results of the analysis of economic indicators showed that the areas in the western parts of the city are hotter and more color spots, But in the East and South East areas neighborhoods, like Shahrdari, Sepahdegaran have in colder and less color spots. This actually shows the cluster distribution of economic indicators. Also the results of the analysis of social indicator showed that spatial distributon is cluster neighborhoods like Khosow Abad, Masnav, Chahar Divari, Mobarak Abad are in the hotter spots and neighborhood Adab, Varmaghani, Hassan Abad are in colder spots.The resualts for environmental indicator reveals that spatial distribution is cluster. Mriginal neighborhoods are in colder spots and Nezam Mohandsi and Shardari town and Degaran allocated the lowest Z. In contrast neighborhood like Mobarak Abad and Khosrow Abad are in hotter spots. Analysis of hot spots for total livability implies that neighborhood in West area of city follow clusters of hotter spots and the South East neighborhood follow colder spots. This can result in injustice in space services and the lack of performance in order to improve the quality of the environment and quality of life in area, livability is defined as one of the aspects that could contribute to a high quality of living, because high quality of living will affect citizen's lifestyles, health condition and shows stability of the built environment. most researchers agree that livability refers to the environment from the perspective of the individual and also includes a subjective evaluation of the quality of the place so measurement of urban livability for all places promote the perception of urban managers and planners and with such knowledge, the path will be open for practical, creative and futuristic management of the urban environment. In relation to the livability of neighborhoods to each other, spatial and non-spatial analysis shows that areas with different ratings are compared to each other. With respect to results of measurements of livability: centrally located neighborhood is more livable than their peripheral counterparts which may calculate that location has significant importance in the pattern of livability. Therefore spatial distribution of dimension and index of livability is not the same extent.The results showed that between main dimensions of neighborhood livability is not different. But in terms of spatial distribution, three dimensions are not equally distributed and it is cluster. Ranking based on total index indicate neighborhood of Khosrow Abad with score (3.279) is ranked at first and Sharif Abad with score (2.228)is ranked at last.
The Iranian plateau formed by the active tectonics of the Alpine-Himalayan belt, is situated between the Eurasian and Arabian plates. The plateau is considered as one of the most seismically active regions in the world and is faced with different earthquakes each year. Active tectonic conditions, different faults and seismic sources and a large population in earthquake-prone areas makes it necessary to perform more considerations and scientific studies in order to analyze the seismic hazards and risks.
In this paper, different aspects and effects of the Iranian seismicity has been determined. In order to review the status of seismicity and distribution of earthquakes in Iran, we need first to consider the tectonic setting, structural environment and the active faults of the country. To date, there have been some different studies to divide the the seismotectonic setting of Iran into different seismic zones which are explained in this paper briefly. Moreover, the seismicity and most destructive past earthquakes in the Iranian plateau and distribution of earthquakes are shown.
One of the most important tools in studying earthquakes is to perform continuous recording and monitoring of the seismic event and ground motions which is implemented using seismic and strong motion networks. The systematic networks have been set up within the country and are working and responsible for data collection and monitoring of seismic events permanently. These networks including the Iranian Seismological Center (IRSC), broadband seismic network of the International Institute of Earthquake Engineering and Seismology (IIEES) and strong motion network of the Road and Housing and Urban Development Research Center (BHRC) are also introduced in the current study.
Given the high seismicity rate in Iran and rapid development and growing of the populated cities and buildings on seismic hazard prone areas, attention to seismic hazard and risk assessments has been become as a particular issue that should be addressed carefully. Therefore, seismic hazard analysis and estimation for the constructions of human structures has become an enforcement for which several seismic regulations and codes have been defined. In this regard, deterministic and probabilistic seismic hazard methods have been developed as the two most important techniques. The deterministic method is a conservative approach that is mostly used to determine the highest level of strong ground motion (acceleration) for a special site (such as dams and power plants). On the other hand, the probabilistic method provides probabilities of different strong ground motion levels considering different uncertainties and the useful life of a structure.
In addition, considering the level of seismic hazard in a region and its population can lead to risk assessment, vulnerability and resiliency of the human societies. Thus, parallel to seismic hazard and risk analysis, it is so important to conduct crisis management, reduce efforts and a continuing assessment of the situation in the country. In the present study, problems and challenges facing the crisis management, as well as urban distressed areas are mentioned.
Regarding the existence of constant threat of natural disasters, especially high risk of earthquakes, there is a serious need to conduct more scientific researches in various fields, including detailed research on various aspects of seismology in Iran, retrofitting of constructions, crisis management and disaster risk reduction. To achieve this purpose, we need a scientific network in Iran. There sould be several experts and organizations as the members of this network who are able to understand and control the earthquake effects on the society. Necessity of such a scientific network is due to that it is impossible to take efforts in order to reduce the earthquake risks without a holistic perspective and earthquake data completion.
In this regard, we need significant infrastructures in terms of human resources and technical cooperation to motivate a set of organizations, universities and research institutes. The responsible organizations such as geological survey of Iran, National Cartographic Center of Iran, meteorological organization, Institute of Geophysics of the University of Tehran, International Institute of Earthquake Engineering and Seismology, Road and Housing and Urban Development Research Center, National Disaster Management Organization, Red Crescent Society of the Islamic Republic of Iran, as well as universities and NGOs must work together to make it possible to review and integrate the existence potentials and to share the information and data of the earthquakes in Iran and define various response scenarios faceing natural disasters, especially earthquakes.
In advance crisis management of natural disasters, particularly earthquakes in urban areas is one of the necessities of urban planning. However, nowadays with the help of technology we can determine the risk of crisis in the urban areas and settlements. Due to population growth and increasing urbanization, the occurrence of natural disasters such as earthquake can cause terrible disasters in the cities. The need to reduce the vulnerability of the cities is one of the main objectives of physical planning of urban areas and city designing. The city of Kashmar in one of Iran's earthquake-prone areas (due to its adjacency to the Lut fault) has witnessed the sever destruction from the September 25, 1903 earthquake (with a magnitude MS= 5/9) and Torbat Haidariye earthquake on 25 May 1923 (a magnitude MS= 5/8). It is very important to identifying vulnerable areas to earthquakes in advance. Accordingly the objective of this study is to identify the vulnerability of urban areas of Kashmar city to the earthquake by using VIKOR model of urban planning. The vulnerability of the city was computed on several parameters among which the population density is the most important one.
In order to carry out the research eleven population and other indices were used. These indices are as follows:
By using the VIKOR ranking model the vulnerability of the urban areas of the city was identified and classified. The correlation between the city vulnerability and each of these indices was calculated. The impact of the indices on the city vulnerability was calculated according to the AHP model.
The results of the study showed that the zone 3 had the highest and the zone 8 had the lowest physical vulnerability in the model. Based on the results of the Spearman correlation, the impact of the population on the vulnerability was about .5866 which is relatively noteworthy. This means that highest degree of vulnerability can occur in very populated areas of the city. All of the city was regionalized according to the degree of vulnerability to earthquake.
The lack of amenities and facilities such as health centers, fire stations, building materials and weak areas within the city will increase the losses and casualties. It is noteworthy that comprehensive city planning in the future must improve and the needed facilities should be provided. In addition providing services to the residents, especially in critical times after the earthquake should be provided.
Groundwater resources are important sources for the supply of water in agriculture, industry and drinking in Ardabil plain, therefore underground water resources planning and sustainable management of these resources are important. The purpose of this study is grading the villages in the plain of Ardabil in underground water crisis and changes during the years 1360-1391. The information obtained from 39 wells, piezometers in plain of Ardabil. Using simple techniques and fuzzy cumulative weighting and interpolation methods, the piezometers interpolation of shallow water table and how it changes during the period is showd.
Introduction
Groundwater is one of the main sources of drinking water supply for many people around the world, especially in rural areas. Groundwater can be contaminated by natural or human activities are numerous. All activities including residential, municipal, commercial, industrial and agriculture can affect groundwater quality. Groundwater contamination can result, such as the loss of a source of water supply, high cost of clearing the high cost of alternative water supply or cause potential health problems. Given the importance of determining the results of the plains of the country, the aim of this study was to determine changes in aquifer storage of Ardabil using statistics and analysis on multi-criteria decision-making and evaluation of groundwater is a crisis situation.
Data and Methods
In this study, the data of piezometers wells in of Ardabil plain scattered through the city of Ardabil Regional Water Authority have been prepared. Also, the surface layers and point to the plains of Ardabil, political divisions and the location of wells, piezometers villages for final maps have been used. The data of deep wells, as well as cultivation of four major product with a high water requirement of wheat, barley, potatoes and forage to determine the relationship between ground water and water harvesting has been a drop in water table.
The study area
Plain study area is located in the north-west of Iran in Ardabil province (Figure 2 and Figure 3). The average height is about 1360 meters above sea level It covers an area of approximately 820 square kilometers and is located in the Gharasoo watershed.
The first step is to evaluate each process and required hydrological data collection, and the coordinatingits location. The geostatistical methods of IDW, GPI, LPI, and RBF in the ArcGIS software were used for interpolating all existing data and a drop in water table in the area of standards for grades 10 class (raster) within restricted fields of Ardebil were determined.
Finally, using simple collective weight, weight-bearing layers and layers of loss data water table for the years 60 and 90 is obtained. To get the final map of water table drops, the two layers are deducted and the final map of Ardabil plain water table drop that phase is obtained.
Analysis showed the reduction of water table almost 47 percent in 1391 compared to 1360. As can be seen in Figures 12 and 13, maximum of 45 meters water table wells, piezometers in 1360 to more than 70 m in 1390 has come to reveal the deterioration of the aquifer Ardabil.
Pholadloo_e_Shomali district with the highest concentration of deep wells in the near future to continue the removal of existing deep wells, groundwater resources will go into sharp decline.
Sharghi Village goes to the crisis and in the meantime, the central Vilkij district includes the eastern part of the plain, the drop in water table aquifer at greatest risk to the two villages in East and Central Vilkij.
• Due to the limitations of traditional agricultural development potential ground water;
• Increase the efficiency of irrigation, changing crop patterns of water needed to fill low-power consumption;
• Efficient use of water resources and prevent unauthorized digging deep wells to exploit the nutritional front, especially in the East and Southeast plains.
Air pollution has become one of the main problems of cities. Among the sources of air pollution, vehicular traffic plays an important role. Planning for efficient management and control of the air pollution caused by vehicular traffic requires accurate information on spatio-temporal dispersion of the pollutions. This research studies 3D spatio-temporal dispersion of NOx pollution caused by vehicular traffic at Valieasr-Fatemi intersection resides in Tehran, Iran. It is selected for being crowded and having the required meteorological and pollution data sensed by the Air Quality Control Corp. of Tehran Municipality.
This study uses GRAL that is a local micro-scale air dispersion model defined based on Euleran-Lagrangian dispersion models. It investigates the level of spatio-temporal autocorrelation generated by GRAL simulations at both 2D and 3D modes and discusses how it adapts with the reality.
Adopting the GRAL air pollution dispersion model, streets are defined as the linear source of pollution of NOx caused by vehicular traffic. The traffic rate is estimated based on street areas and directions, the designed average traffic velocity, traffic volume and car passage counting at the intersection. The 3D geometry of the buildings is also added to the model. All the required data that were available for winter of 2007 are gathered and introduced into the model.
The model is executed at 9 heights vary from 1.7 m to 52.5 m. These heights are defined covering a range from an average human level height to average building height and above. These levels are considered both separately in 2D mode and integrated into a 3D mode. The formation of NOx clusters is investigated analyzing their autocorrelation using Moran Index at global and local scale.
The calculated Moran-I at global scale at each 9 levels of heights, varies from 0.7 to 0.9 that depicts the validity of the GRAL model adopted to simulate the expected autocorrelation of pollution density affected by spatial issues. The Moran-I increases at higher levels as less air turbulence happens. However the result show that the turbulence increases temporarily at about 10m to 15m which are the average building heights. At local scale, the Moran-I/Anselin shows that HH clusters dominate at lower levels, around streets central areas that are farther from the buildings, and around the intersections. At higher levels, esp. higher than buildings average height, the LL clusters dominate. However the HH clusters formed around intersections, while are shrank, are still visible at high levels. The turbulence caused by building fronts and their down wash effect is also shown in the result as no definite cluster is formed near the buildings front and back.
The autocorrelation analysis is also carried for an integrated 3D model consists of all the 9 levels of heights. Considering the weight matrix for a 20m 2D neighborhood and 1m/s dispersion of the pollution vertically, the global calculated Moran-I equals 0.229 which shows existence of a spatio-temporal autocorrelation of the results generated by GRAL. At local scale the results show that the HH clusters have higher temporal dispersion rate than LL clusters.
Precipitation is one of the important aspects of the Earth’s climate that has both spatial and temporal variations. Understanding the behavior of this element and analyzing its spatial and temporal variation is importantwhich can lead to a comprehensive and detailed planning for water resource management and agriculture. Geostatistical techniques and spatial autocorrelation analysis are the most widely used techniques in the field of the spatial continuity. Spatial autocorrelation analysis is applied to help researchers understand the spatial patterns in the area.
The purpose of this study is to identify the heavy precipitation spatial patterns in Guilan Province. For this purpose, the 6- hourly sea level pressure of the network from 0 to 120 Easter longitude and 0 to 80 Northern latitude with 2.5×2.5 degrees spatial resolution were obtained from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) for the period 1979-2010. The daily precipitation data of 21 stations were obtained from the Islamic Republic of Iran Meteorological Organization and Ministry of Energy.
Guilan province is one of the most humid regions in the country. The heavy rain days were selected as days when more than 30 percent of the all stations had daily rain amount more the 95th percentile. As a result, 321 days were selected as heavy and widespread rainy days. By using principal component analysis these 321 days were reduced to 9 factors. These factors then were subject to cluster analysis with Ward method and resulted in three surface pressure patterns of heavy rainy days. Within the resulted pressure patterns by using local geostatistical techniques we identified the heavy rain spots and their spatial orientation. These spatial methods include Kriging, Geostatistical Analysis, and Anselin local Moran index.
According to the results of this research, the first pattern was characterized with a high pressure over northern part of the Black Sea causing the highest Variance of heavy rainfalls. The second pattern is identified as a low pressure on the Black Sea. But the third pattern showed a precipitation distribution with low variation caused by the Siberian high-pressure. The results of Spatial Statistics techniques indicated that heavy rains were clustered in all there patterns. The clusters of heavy rains were localized mostly over the coastal areas and some over the central regions. The clusters of the western high-pressure patterns penetrated somewhat inside the province, while clusters of the Siberian high pressures was located on the shoreline of the province. The precipitation of western migratory high-pressures was heavier than of the Siberian high-pressure. The results of the standard deviation ellipse showed that heavy rain clusters were oriented in the east-west direction and were nonhomogeneous. While the ones oriented in the south east direction were more homogeneous and clustered. Because of this arrangement, the entry of moisture from the Caspian Sea is relatively concentrated on the East or North East. Because of the concentration of heavy rains in the central areas of the coast, the risks of floods and soil erosion is very high in these areas. This study showed that contrary to the popular belief, the heavy rains of Guilan were produced by western systems and the role of the Siberian high pressure is less important and is limited only to the coastline.
Every year, natural hazards happen severely around the world. Iran is included in the first 10 countries in the world susceptible to natural hazards, and has experienced 30 hazards out of total 35 hitherto. In this connection, moving sands, as a natural hazard, creates changes to ecological conditions which cause a rupture in the lives of people. The aforementioned hazards leave adverse effects on human habitations and impose wide environmental and socio-economic damages upon societies. Moreover, the sand mass covers arable lands and residential areas, generates air pollution, brings in destruction of topsoil, harms animals, and brings about many losses. This eases desertification and causes damages. Therefore, taking areas subject to moving sand into consideration is very significant in rural planning. Hirmand township in north of Sistan and Balouchestan province is an area open to moving sand onrush. Unfortunately, due to Sistan drought and Hamoon international wetland dryness as a result of the dominant120-day winds in the area, moving sands have come to affect rural settlements. This has put the villagers of Hirmand township to so much trouble. Hence, an investigation and analysis of rural settlements vulnerability to moving sand damages in the villages of Hirmand township is of great significance as a step toward better control of the problem.
The present study is a descriptive-analytic survey containing documentary sources, field studies, as well as village and household questionnaires. The statistical population consists 303 villages in Hirmand township, from which a total of 56 were selected as the sample of the study based on advice given by experts at Housing Foundation of Islamic Revolution, rural administrators and local council members. Analytic hierarchy process (AHP), statistical analyses, spatial analyses, and the software Expert Choice, SPSS, and ArcGIS were used in data analysis. This study, hence, attempts to identify vulnerable habitations and categorize them by employing 54 indexes and assessing and putting them together in different levels.
According to the findings of this study, from the total villages subject to moving sand problem, 55.35 % are found with low or very low vulnerability and 30.38 % are placed in high or very high vulnerability ranges. The investigation of distribution of the villages under study given the vulnerability intensity to moving sand storm revealed that the villages of low or very low vulnerability are situated in the central and western parts of the area under study. These villages enjoy low vulnerability due to water resources, Tamarix hispida trees planted by state-run entities in the moving sand paths, and being away from dry bed of Hamoun Wetlands. On the other hand, the villages of high and very high vulnerability are placed mostly in the northern part of the area under study and adjacent to Hamoun Wetlands.
There are several factors playing key roles in vulnerability of rural areas including environmental elements such as stopping of incoming water flow into Hamoun Wetlands, winds of 120 days, wide geomorphological functions of moving sands, and high reduction in the density of vegetation and trees around and in the villages due to drought. In addition to the above factors, inconsistency of physical context of villages with the movement direction of moving sands has caused accumulation of sands in villages which is effective in vulnerability intensification of many rural areas.
Ruin of houses and cut of communicative roads by moving sands cause disruption in normal lives within the aforementioned villages. In addition to taking damages by moving sands into consideration, the evident role of state services is very significant in decreasing of the damages in all parts of Hirmand. In this connection, belt-like flood preventives built around the international Hamoun Wetlands has made moving sands accumulated behind them and this has decreased intensification of the damages and probable threats from sand onrush to the lower latitude regions.
Accordingly, the results of affecting level comparison of different factors in appearance or intensification of the moving sand’s effects in the villages under study revealed that the effects of weather factors and water restrictions sprung from hydrological droughts in which the incoming flow of Hirmand River into the area under study is cut or decreased remarkably, along with summer winds (winds of 120-days) and severe winter winds are more clear and stronger in intensification of soil erosion and formation of moving sands than other factors.
On the other hand, the results of impressionability level comparison of different contextual-spatial factors in the villages under study demonstrated that sand affects arable lands and water supply networks more than other factors.
However, given that reduction or stop of incoming water flow of Hirmand River into Sistan region over the recent years has caused successive droughts, some factors like drying of Hamoun Wetlands, intensification of environmental dryness, reduction of vegetation and increase of soil erosion along with Sistan’s winds of 120-days have paved the way for increasing of dust storms and movement of sands toward the villages of the region.
The temperature as an indicator of heat intensity is one of the basic elements of knowing weather. The frost is a condition when the air temperature is less than 0 c Due to the geographical possition of Iran, spring is a season that plants resume a new life after leaving a pause in a periode of the growth. At the beginning of such a periode emerge of sudden cold cause loss bloom (in the case of openinig) or delay in a beginning of plant growth periode (Azizi,2002). Recentley with occuring climate chaos, one of the important climatic disasters which treats human and particularly different areas of the country are cold waves and sever frosts that in some years covers large area of the country.
Surface data including minimum daily temperature of the days of 29 to 30 and 25 to 26 of march of 2003 and 2005 in 9 meteorological synoptic stations in the area of north west of Iran in table (1) was collected from meteorology organization then the days of cold waves in the above mentioned time periode, were analyzed. In ordet to analyse the synoptic patterns, using ncep/ncar data, maps of sea level pressure ,combined of geopotential height and vorticity and temperature advection using Grads were drawn and analysed in the levels of 1000 to 500 hpa.
As it mentioned, during the time period, 29 to 30 and 25 to 26 of the march in 2003 and 2005, 2 clod system were located on the area of north west. In oeder to explain and analyze of synoptic patterns of mentioned period time, the absolute minimum temperature below 0 degrees celsius of stations in western Azarbayejan province were selected and maps of sea level pressure, combined of geopotential height and vorticity and temperature advection using Grads were drawed and analysed in the levels of 1000 to 500 HPA.
The results showed that in the time of occuring hazardous cold waves of 29 to 30 of march 2003 and 25 to 26 of march 2005 and analyzing the sea level map in the first day of cold wave with spreading the cold core high pressure from the eastern Europe and its location on north and east north of the black sea and its pentration from north west corner of the country covered most of the areas of the country.
Analyzing the combined maps of geopotential height and vorticity in the levels of 1000 and 850 HPA in the first day of occurrence of cold, generaly faced with huge anticyclonic development . But in the levels of 700 and 500 HPA , the under studied area was in the south trough of the obtained cold core of the low height locating in the cetral Asia. But on the day of cold peak, high pressure core was exactly located on the under the studied area . Also in the upper levels of atmosphere with locating the back of the trough cumulated of cold air of upper width on the sea level high pressure centre while strengthening the lower levels anticyclonic flows, led to intensifying cold and frost in the west Azarbayejan province.
Positive and negative vorticity maximum cells, also conformed the intensity cold circulation flows on the north half of the country in anticyclone and cyclone centers in order. Also analysing the temperature advection in the levels of 1000 to 500 HPA, direction and temperature intensity exactly followed geopotential height maps patterns.
Such that in the levels of 1000 hpA of the both cold wave analysed, the anticyclonic cold temperature adcection and northward is located on the north west of the Iran. In temperature advection maps of 29 and 30 march 2003 in 850 HPA in Azarbayejan province, the anticyclonic circulation is matches with sea level high pressure. But in the 2nd cold wave that’s occured on 25 and 26 march 2005, the north west area is between 2 antycyclonic circulation on Mediterranean and cyclon located on south of Russia that the directions of temperature cold flows is completely north ward in this level.
In the temperature advection maps of 700 and 500 HPA, the Azarbayejan province is in the western edge of central Asia trough or south of Russia.
The results showed that with studying atmospheric motions and synoptic systems which create cold flows, we can prevent of spring late emergence cold wave destructive impact on agricultural products, energy consumption, and road accidentd by forcasting of these atmospheric conditions.
The extent of poverty, inequality and environmental differences patterns in large metropolises are the results of a dual economy with free market capitalism rule in these cities. Urban spatial structure expansion and incoherent, irrational focus on different parts of the city and its facilities and services, economic development, social inequality in them. Urban environments, complex systems with complex phenomena, relations and interactions between the components are different. Cities in the twenty-first century are undoubtedly one of the great challenges which are facing to them is their poverty focus. The physical differences reflect the existing inequalities in societies based on market economy. Undoubtedly, the developments in the past few decades have a large share in these settlements in the metropolises of the country. . Although the extent of urban poverty phenomenon is not new in urban planning literature, referred in ancient societies, such settlements are massive and complex phenomenon, which is entering its second phase of capitalism, the capitalist industrial and disturb Aboriginal settlement system is embodied in the geographic ranges. This astonishing growth in the South with the growth of the tertiary sector of the economy on the one hand and on the other hand, the recovery of the agricultural sector in rural areas occurred. Geographers look at the formation of the spatial extent of poverty regarding both humans and nature.
Poverty is caused by humans in the absence of proper mechanisms in human society develops. Arak urban space reflects the socio-economic imbalances and the spatial extent of poverty in the Border areas of the city.
This research aimed to identify and Rank urban poverty in the Arak city. According to recognition type of this problem, descriptive – analytical methods are used in this research. The multiple components of economic, social and physical are studied. ArcGIS is used to determine the Density factor () and the distribution of each indicator. Then, according to the purpose of the study, stratification between the known areas (including: the city center, 20-meter-Mighan, Davaran and Koshtargah, Roodaki and Bagh Khalaj, Footabal, Shahrake valiasr and Qanate Naseri) And the quantitative model and AHP & ELECTRE Regionalization are used. In this way ranking options instead of a new concept called "non-non Ranking” used. Multi-criteria problems to deal with a set of options, indices and values expressed preference. In this way all options non-ordinal comparisons were evaluated using non-effective options and be removed from list. The results of this paper showed two spatial extent of urban poverty and Regionalization of the settlements with the use of multiple components classified. The results showed that due to the combination of multiple indicators of social, economic and physical, seven main ranges were identified that except for the central part, all extents located in the Border areas. According to the results, the central district (first), 20-meter-Mighan Street and Rudaki and Bagh Khalaj neighborhoods (second), Football neighborhood and Vali-e-Asr (third) and neighborhood of Qanat-Naseri (fourth). Review the history of the formation and spatial differences in this field indicates the fact that different mechanisms are involved in creating them. These ranges are more vulnerable to poverty and poor economic conditions in the exodus of migrants entering and after industrialization city. It can be said that in order to identify the extent of poverty, systemic view of the external and internal mechanisms in terms of time - place is essential.
Urban planning has to perform seismic pathology of urban streets in seismic cities. Streets and roads are the most important spaces and urban elements in the cities which should be considered not only in space occupation and connecting spaces and urban activities but also in seismic vulnerability and on this basis it is planned to reduce environmental hazards and on top of earthquake-related. Many physical and functional characteristics of urban spaces and the distribution and concentration of the urban population take shape to comply with the location, capacity and function of the city streets network. Therefore, one of the most essential and the most important topics in the study of seismic cities is understanding of the relation between seismicity and urban streets through seismic vulnerability studies. This paper aims to assess factors and patterns of seismic vulnerability of urban networks with a prevention planning view in the 3rd district of Tabriz City.
This research has descriptive-analytic method and the statistical population is street network of 3rd district of Tabriz city. Data and layers of information have been prepared by documentary method and have been processed using the Delphi method and the method of ranking and rating IHWP in GIS. The main factors and indicators influencing streets vulnerability have been selected based on the eight indicators. These indicators include distance and proximity to faults, quality of buildings, the degree of closeness (width of the wall), building density, population density, the traffic service or traffic volume toward roads capacity, access to health centers and services and the land use system. The final map of seismic vulnerability has been produced by combining eight layers of information related to above mentioned indicatorsand based on it the seismic vulnerability levels and factors of the street network has been analyzed.
The final results of the seismic vulnerability of streets have been categorized in the 5 classes of vulnerability including very low, low, medium, high and very high. From total area 18.4% is estimated very low, 29.37% low, 31.77% medium, 14.21% high and 6.22% very high. Thus, taking into account the streets with medium, high and very high degree as vulnerable axes, it is concluded that 52.2% or more than half of the streets are seismic vulnerable and other half are relatively stable.
Within the vulnerable and unstable network, more than 20% of the streets are in high and very high vulnerable classes. Street network with high and very high vulnerability are mainly arterial streets with commercial and service land uses in the scale of trans-regional or secondary roads leading to artery of trans-regional which have high population density. These streets compose a high degree of closeness, increase in traffic service level, population density and land use system with the concentration of commercial, recreational and trans-regional land uses are the main causes of vulnerability. But, in the narrow streets (8 to 10 meters), the degree of closeness of arterial streets, traffic parameters and user system have increased the seismic vulnerability index. Spatial pattern of streets vulnerability has an increasing trend from East to West and from North to south. The results show Spatial intensity of vulnerable streets is located at the center of the district and on Vali Asr, Shariati, Aref and Razi Streets. Thus, the efficient and sustainable streets are located in the East of the under studied district.
The results also show that high vulnerable streets has less distance to fault and more distance from medical centers. In addition, they have high traffic and lower quality buildings and high risk land uses (electric and gas infrastructure) are located there. Since the wide streets are more often subject to less obstruction, this characteristic in seismic time cause to transfer the traffic of narrow passage to the main streets. Grid pattern of streets and frequency of intersections by slowing down the speed of the vehicle increase the volume of traffic and lead to an increase in seismic vulnerability.
Nowadays, the adaptation of urban crisis management with urban development plans is considered as an efficient way of cutting back on damages and it is essential to predict economic and physical susceptibility of families and communities. Therefore, considering the urban crisis index can play a significant role in urban planning. Tehran city thanks to geographic location, climate conditions and geological conditions is among risky cities so that the presence of seismic faults has made this city potentially seismic and in need of comprehensive crisis management; it needs to be confirmed that despite the earthquake potential in the region and the quality of the buildings especially in old and organic texture and other parameters such as access network and buildings and skeletal disorder the occurrence of a large scale earthquake and other natural disasters would be very catastrophic. For this purpose and given the high susceptibility of the region such as the impression by the North and South Rey fault, hazardous industries and fundamental establishments on the one hand and the presence of worn-out texture on the other hand were the reasons behind choosing this region to do the research.
This research is descriptive-analytic in terms of data collection and practical concerning the function. The location of study is 20th municipal district of Tehran. The area is about 23 square kilometer and by including the range about 200 square kilometers. The research population consists of 500 experts and administrators engaged in preparation and practice of detailed municipal plan of Tehran city and crisis management organization of Tehran city. The research mass was selected at 217 persons by the use of Cochran’s formula. The sampling method was random classification method. Data collection instrument was the use of author-prepared questionnaire which consisted of four parts. Measurement instrument validity by facial method and its reliability was examined using Chronbach Alpha. Therefore, after providing the required acceptable reliability among 20 persons of the subjects the personal attendance method of distribution was applied.
The research findings show that among research variables, locating crisis management uses within detailed plans received more attention (Mean:82/36) and the knowledge of crisis management within detailed plan management process received less attention (Mean: 24/08). Also the study of distribution indices using standard error deviation and variance reveals that the type of responses to the variable of attention to risky use policies (standard deviation: 4/08) has low distribution and attention to crisis management uses (8/49) has high distribution. For ranking variable conditions Freedman test was implemented. The results obtained from this test showed that the variable of attention to crisis management uses with the mean of 3/81 ranked first and attention to crisis management knowledge within detailed management process with the rank mean of 1/00 stands fourth on the list. The obtained results from the Pearson test also show that among all variables there is a significant relation with a confidence level of 99% and the correlation among them was positive. Also the highest correlation coefficient was attention to the crisis management uses and attention to crisis management knowledge at the rate of 0/898 and the least correlation is about the relation between the variable of attention to knowledge of crisis management and the reflection of crisis management indexes on detailed project plans at the rate of 0/423.
Considering the obtained results can conclude that crisis management indexes through the process of preparation, approval and the administration of detailed projects of Tehran city and 20th municipal district have not been attended sufficiently. For instance, skeletal features determination and operational properties at each urban scale were given the rate of susceptibility and the natural place limitations to enhance escape possibilities and people refuge (apposite building type, low building density, use of paths as the getaway and refuge spaces etc.) have not been estimated and their impacts have not been included in development plans.
Also neighborhood was expected to be observed in urban lands use determination and avoid incongruous uses next to each other and provide quick exit but such cases have not been attended in detailed Tehran city project and 20th municipal district or that the intended issues have been briefly listed and practically had no use in administration stage. In fact, the bad condition of the skeletal elements location and inapposite uses of the urban lands, deficient urban network, compact urban texture high urban density, improper location of fundamental establishments and shortage and improper distribution of urban open spaces etc. which have critical role in boosting up the rate of inflicted damages to Tehran city against crisis on the basis of the experts’ vantage point has received insufficient attention and while discussing the issue there is no coordination among related organizations concerning a serious attention to such indexes.
The appearance of Hazards in human life is affected by natural and human forces. So far, human beings were the most powerful stimulant to create these hazards and to intensify them. The negative role of human beings in environment is caused by factors like lack of knowledge, weak reaction, technology lack, aggressive ideologies and competition; in social system, however, human behavioral engineering especially in dealing with nature is totally affected by management system.
One of the common human behaviors which place in economic system framework is extraction and exploitation of Mines that has many consequences for ecosystem. In fact, Mines are the result of human beings reactions in dealing with nature which their activity ranges are increasing. According to micro-scale to macro-scale in economics, economic life of a country like Iran is based on its huge natural/mineral recourses.
On the other hand, environmental consequences of exploiting Mines in this country are numerous and varied. In this study, we tried to present a spatial-temporal analysis and explanation about environmental hazards phenomena in the case of exploiting Mines of the country caused by human beings with the title of "anthropogenic hazards in Mines” that is totally a result of its respective management system.
In terms of its objectives, this study is a practical research and it is a descriptive-analytic one. For data collecting, we reviewed the existing literature and surveyed the data base in Statistical Center of Iran. These data are extracted from 2009 census and 2013 census (because of limited statistical domain) which belong to all the provinces of the country. To perform the analysis, these data are collected based on 5 indices and 16 sub-indices and after completing data base, percentage distribution graphs for Mines and environmental activities in the provinces (in 5 total framework) has been drawn by using GEO DaTM software. Following that, by using a multi-criteria decision making method (COPPARS) all the regions are ranked according to the level of their environmental hazards in exploiting Mines. Finally, to illustrate the spatial pattern and method of hazards in Mines in the country on the studied period of time, based on COPRAS method, the calculated standard deviation ellipse was drawn in GIS which is according to 2009 and 2013 data.
Studying the increasing number of Mines which are exploiting in the provinces of the country during 2009-2013 confirm that most of the provinces had experienced a positive growth during this period of time and among these areas Ardabil, Alborz, Ilam, Bushehr, Tehran, Kurdestan, Qazvin, Fars, Luristan and Hamadan provinces had experienced a negative growth and we can mention to other economic activities reinforcement as the reason of this negative growth such as services in Mines section rather than activities in this section, spatial location and the influence of border line or ignorance of planning system. On the whole we can conclude that in economic system of the country, there is a constant attention to Mines and expansion of their exploitation in the area.
According to the findings of this study, we can conclude that in spite of the existence of Mines which are extracting in all around the country and the expansion of exploitation of these resources in these regions, required attention and consideration is not paid to decrease or modify destructive effects on environment in the case of Mines which are operating in the country, on the contrary indices such as investment and increasing the value of investment had decreased, and by considering the inflation in country, it can be said that economic attention to Mines management in the country to reinforce the basis of environmental compatible Mines is insignificant and declining. So it is not out of question that exploitation of these Mines in this country is an effective and intensifying factor to create and intensify other human-made and natural hazards.
In regional point of view, management activities which modify negative and destructive effects of exploiting this country's Mines (maybe in a small scale) are done by ignorance to regions that have predetermined hazards and it seems that other factors are used to conduct and strategize the environmental compatible management engineering in exploiting of the country's Mines not the systematic management factors; for example, according to Iran's Environmental Protection Organization (EPO) statement, Isfahan, Fars Yazd, Khuzestan, Bushehr and Hormozgan provinces are dealing with the highest level of environmental hazards (IRNA, 2015), while these provinces have the most hazardous Mines and they are located in the limited area of anthropogenic hazards of Mines or they are close to regions that have maximum Mines ' hazards. In industrial provinces as Isfahan which are dealing with water scarcity and environmental pollution too, "anthropogenic hazards of exploiting Mines which are the result of management" could create hazards like different kinds of water and air pollutions and they also enforce spatial environmental hazards.
Finally, according to spatial-locational movements or changes of place, related to anthropogenic hazards of exploiting Mines in Iran, it can be said that the dominant approach on economic system of region which is related to Mines is proceeding fast to important population centers of the country and similar problematic ecosystems which may cause the appearance of hazardous crisis in some parts of the country.
With the development of economy and social services, increased need to reduce risks, control risks and other important measures in order to provide program management and follow-up plans vulnerability, Having the right information and understanding the current situation in the field is essential for prevention and planning measures, Therefore, research on risk reduction and knowledge of threats in the Arangeh region is essential, as one of the areas tourist attraction regions in Karaj's catchment area.
Geomorphology of River studies landforms and processes of river and predict changes using models and field studies and laboratory. And new analytical tools and techniques, growing and expanding with the help of river engineering.
This eventually leads to gain new capabilities in the field of river management, landscape restoration, risks and geomorphological studies ancient river.
In most cases geomorphological processes that are created by river systems, are causing environmental hazards of natural and human environments. In this paper, we have investigated the risks of geomorphic processes, especially risks of flooding and river flooding and is calculated for the maximum flood discharge for subarea also. In this article, it has been found that most of the flood will be calculated based on the map of the geomorphology of the area and the discharge sub basin. The purpose of this study, is assessing damages caused by the flood risks in the area. It is obvious that the results of this study will enable the pre-crisis phase of the crisis management system and can help to tourism and physical planning in the area.
Arangeh basin is an area of 10,090 hectares and a maximum height of 3665, at least 1637 m and average height of 2689 m. Arangeh area have an annual precipitation about 785 mm. Arangeh watershed is located within the northern city of Karaj, 15 km Karaj Branch, Karaj Dam east side of the river and inferiors (Amir Kabir).
In this study, to analyze the flood in the basin, a variety of sources are used including surveys of library data and documents, topographic base map scale of 1: 25,000 geological map of 1: 100000 taken from the ground geological, climatic data obtained from meteorological Organization, hydrological data obtained from regional water Alborz Landsat satellite image.Also field visits, the use of GPS and GIS software Arc GIS Version 10 was main parts of the survey.
The calculated concentration time by Krpych method to estimate the flood of data base, then estimate is based on a regional analysis of runoff and peak discharge of flood.
According to Hydrogeomorphic properties basin unit (sub-21) has the maximum flood discharge which is mostly covered by alluvium and located on the ground impermeable siltstone, waterways due to morphological features steep, mountainous dominant morphology, concentration time low basin, poverty and lack of vegetation (about 15 and 50 cubic meters per second in the 50 and 100-year return period). Other sub-basin with high flood discharge of sub No. 3, 5,7,9,12,14 and 16 are in Central, East, North, East and South of the basin villages.
Many parts of the Arangeh basin has slopes of more than 60%, which is an important factor in the effect of runoff, reducing the time of concentration, poor soil and vegetation and is an important factor aggravating flood risk and erosion. The presence of vegetation in these areas can have an important effect in obstructing runoff, reduce the rate of runoff, reducing flooding and consequently the reduction of soil erosion. We can largely control the flood basin watershed management practices and proper management range in the above units.
Land degradation in arid, semi-arid and sub-humid areas, leads to desertification and land degradation is a concept that refers to any reduction of soil potentials. In Iran, that 85 percent of its area is classified in arid and semi-arid climates, and one percent per annum growth rate of desertification and its increasing trends, finding ways to evaluate this phenomenon and its causes in the form of models seems essential. In Iran, especially southern areas due to their arid climatic conditions, are considered to be areas prone to desertification. This study aims to evaluate and analyze the vulnerability of desertification in the Mond watershed located in the northern coast of the Persian Gulf.
In order to evaluate the potentials of desertification in the Mond watershed, geological, the erosion (water erosion potential), rainfall, slope, elevation levels and land use maps are used. To identify vegetation cover conditions Landsat ETM + sensor data and normalized vegetation index (NDVI) are used.
Where in reflected in the near-infrared band (Band 4, Landsat ETM+) and the reflection in the visible band (band 3 sensor ETM+) respectively. Overlaps and combines the above criteria is done using E-VIKOR (VIKOR developed) a method of multi-criteria decision-making models (MCDM). This method is based on a compromise plan proposed in the compromise solution is justified determines solutions that are as close to the ideal solution and has been created through special credit decision-makers. VIKOR use linear approach normal. The normal value in VIKOR is not related method unit of measure. Also standardization effective indicators of desertification has been done using a linear scale.
In this study, the ANP method (Analytical Network Process) was used for weighting criteria. Analysis method Network, is one of the popular methods of multi-criteria decision problems. This method complex relationship between and among the elements of the decision by replacing hierarchical network structure considers. Table 1 shows the weights of the effective criteria in desertification. In this study 7 criteria are used that results show criteria’s of climate and vegetation, have the most effective measures in the area of desertification and erosion (water and wind) have the least amount of importance in the region.
Table 1: weight criteria of effectivein desertification
criteria |
vegetation |
erosion |
Precipitation |
Landuse |
Geology |
Slope |
Elevation levels |
weight(W) |
0.21 |
0.18 |
0.15 |
0.14 |
0.13 |
0.11 |
0.08 |
After mapping the effective indicators in evaluating desertification separately, Standardization of maps, weighting the index, To obtain amount and , Finally, the amount of , was produced Zoning map of desertification that in it Mond watershed in the province Bushehr in terms of desertification is divided into five ratio and the area is provided in Table 2.
Table 1: Percentage and area zone of desertification
amount vulnerabilities |
Area (ha) |
Area (in percent) |
Very low |
516300 |
11 |
low |
598900 |
13 |
Average |
1438025 |
30 |
High |
2168675 |
46 |
Very High |
40825 |
1 |
Studies show that more than half of the Mond basin have on the surface with average risk of desertification and In the continuation of the current trend of soil degradation, desertification prone zones and will be reduced all lead to the deterioration of the natural ecosystems and human life quality.
The runoff simulation have particular importance in Civil works, river training, design and planning of ground water resources, flood control and prevention of environmental hazards and reduction of erosion and sedimentation in the watershed. The runoff in each region varies according to climatic conditions, hydrological, soil and vegetation in the basin. Simulate these processes need to provide the necessary information on the spatial variation of these factors. In this context, given the diversity of hydrological models, to achieve the most appropriate simulation of hydrologic models and choose the appropriate model requires the evaluation of their performance in each area is commensurate with hydrological conditions. So hydrologicl models, need to recognize the capabilities and limitations of basins. In this study, the performance of the two models of rainfall – runoff including IHACRES and SWAT models was compared and evaluated in runoff simulation for two watersheds Yalfan and Sulan in Hamedan province in West of Iran .
The SWAT model uses various information, including; hydrometry, climate , soil , topography, vegetation and land use . SWAT (Soil & Water Assessment Tool) is a river basin scale model developed to quantify the impact of land management practices in large and complex watersheds. SWAT model is a hydrology model with the following components: weather, surface runoff, return flow, percolation, evapotranspiration, transmission losses, pond and reservoir storage, crop growth and irrigation, groundwater flow, reach routing, nutrient and pesticide loading. SWAT model uses a two-level disaggregation scheme; a preliminary sub-basin identification is carried out based on topographic criteria, followed by further discretization using land use and soil type considerations. Areas with the same soil type and land use form a Hydrologic Response Unit (HRU), a basic computational unit assumed to be homogeneous in hydrologic response to land cover change.
IHACRES model is a catchment-scale rainfall – stream flow modeling methodology whose purpose is to characterize the dynamic relationship between rainfall and stream flow, using rainfall and temperature (or potential evaporation) data, and to predict stream flow. The model can be applied over a range of spatial and temporal scales - from small experimental catchments to basins; using minute, daily or monthly time steps. It can be used to fill gaps in data, extend stream flow records, as well as explore the impact of climate change and identify effects of land use changes.
Data used in this study includes temperature, precipitation and runoff in the period of 2010-1983. Rainfall and temperature data were used from weather stations and runoff gauging stations from basin Sulan and Yalfan hydrometry stations. In this study we select two periods, first period from 1983 to1999 for calibration and the second period from 1999 to 2009 for validation. Some of the required basic information such as soil, vegetation, topography and land-use maps were used to carry out the research were received from the Research Center of Agriculture and Natural Resources of Hamedan province. Accordingly, after collecting basic data and analysis of the sensitivity parameters, then calibrate and validate the models. To determine the ability of models Nash Sutcliffe (NS) and determination coefficient ( R2) were evaluated .
The results showed that both models are acceptable in simulating runoff in both basins. According to the results obtained in the simulation by SWAT model in both basins, Nash Sutcliffe on a monthly scale in the Yalfan basin for calibration period is 0.68 and verification period is 0. 74 and for Sulan basin calibration period is 0.69 and verification period 0.76.
The flow rate during validation periods have high accuracy. In the Yalfan basin observed daily flow 1.17 cubic meters per second and simulated flow is 1.10 cubic meters per second. As well as an overview of the values of the coefficient of determination can be seen in both basins, amount represents the high precision simulation in monthly and daily scales. Based on the results obtained in the two basins, IHACRES model has been good performance on a monthly scale, so that the Nash Sutcliffe in the Yalfan basin for calibration period 0.68 and for verification periodic 0.72 in the Sulan basin for calibration period 0.64 and for verification periodic 0. 65. In general, both models can be seen by comparing the SWAT model was calibrated and validated with the highest Nash Sutcliffe on the monthly and daily scales. Generally it can be concluded that to simulate the daily and monthly runoff, the SWAT model is recommended for evaluation hydrology process in the Yalfan and Sulan basins. It is essential in most similar studies to determine of rainfall-runoff models with respect to variability of rainfall-runoff models in different climate periods of dry and wet years.
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