نشریه جغرافیا و مخاطرات محیطی
پیاپی 5 (بهار 1392)

In this study, one of the heaviest rainfalls in southwest and central areas of Iran (09/11/87) over the last four years (1387 to 1390) because of the occurrence of the phenomenon cut-off low,. The purpose of this study is to explore the thermodynamic it will rain. First days of rain precipitation data were obtained from the meteorological precipitation zonation map was, charts Holf - Moller and relative vorticity for the days of the draw. The results showed that the index the instability of the heavy rainfall was considerably for on the map it was not an especially severe precipitation is not particularly high rates the anti-cyclone over the Arabian moisture settled on the Red Sea, Arabian Sea and Gulf of Aden to the south west and central areas of the injected The supply of humidity and precipitation has. Also suggests that a significant amount of relative vorticity the position of the trough axis over the Persian Gulf and southern Arabia and quantity relative vorticity values are consistent with each other

This articles aims to identify and zone of Tabriz district level of vulnerability to earthquake danger. This research is applied and development and it is descriptive and analytical research. For doing so، at first، fifteen effective natural and human made criteria in urban vulnerability to earthquake danger were identified according to experts viewpoints of fields related to earthquake and comprehensive and systemic approach. Then the final map was prepared by using analytical functions of ARC GIS software and scale weighting models، AHP and OI and combination of both models and layers resulted from effective factors. The final map shows vulnerable zones. The results of the models were similar based on OI. According to OI model، most parts of the city are in middle zone. It can be concluded that Tabriz has inappropriate situation from earthquake view point and most of the high crowded parts especially north and central parts are in very high and high vulnerable zones.

Mountain geosystems are not unusually fragile but they show a greater range of vulnerability to disturbances that human induced than many landscapes. The combination of extreme geomorphic events with exceptional population growth and land use modifications underlies the urgency of better understanding of these interactions for investigating of the effects of drivers of change on landforms and landscapes. The combination of natural and human factors provides conditions for these unstable events within the geomorphic transport processes. The present study focuses on the identification of the Kan watershed topple initiation factors and the susceptibility ratio zonation of this event using fuzzy logical model. The distance to road، distance to lineament، distance to fault، slope، aspect، slope formation، elevation، land cover، cryocl

Lakes and ponds are considered as one of the signicant beauties of creation، the most advantageous and of the most vulnerable natural ecosystems in the World at the same time. These Vital and varied environments are of life rules that merely have no replacement: how ever، none of worlds ecosystems havae experienced harms due to environmental Jeopardies، superficial activites، short-sighted and selfish desires of man kind as much as ponds have. This study is aimed to investigate effects of oromiye lake level of water on agricultural economy of villages in Marhamat abad shomali of Miyandoab township. Kind of research is applied one، Method of research is descriptive and analytical، Method of collecting literature and at- firld information and analysis of information has been with factor – analysis and in the method of analyzing of the research were harvesting agriculturals of Marhamat abad shomali county based an a qeneral agricultural census in 1382، harvesting agriculturals in this county in this yrar were 1437 which 264 agriculturals of them were selected by kokran equation as the sample volume. Findings of the research illustrate that with water level decrease in oromiye lake and blowing of storm and strong winds، salt get transferred to agricultural fields and causes reduction of planted fields production decrease، some salted fields، decrease of under ground waters، destruction of some fruit trees and at the end leads to decreased eagerness in agricultural activities. In addition the increased cost in the usage of agricultural devices، unavailability of modern methods of production due to lack of knowledge، shortage of income، etc has lead to decrease of employment in agriculture field in the county.

Yasouj region is one of the areas with high precipitation that every year، semi-heavy and heavy rainfall in this area is great. This study has tried to analyze the data at the upper levels of the atmosphere at sea level، 250، 300، 500، 600، 700، 850، 925، 1000hPa climate، heavy rainfall causes loss Yasouj be identified، dated 11/03/2011. Precipitation is essential not only in human life but also in lives of plants and animals and inseparable part of nature is considered. But this is a natural phenomenon that can be as valuable in the peak value as an important is natural hazard risk to human life، flora and fauna. Torrential rainfall that originates from a sudden event that every year the rate of damaging is too severe to be endured in lives and treasure. Iran is one of the world''s dangerous zones that flood is considered as one of the most dangerous phenomenon all year، severe damage to human lives and property and the nature of the marks، especially in recent years sought to exploit human nature and the potential for environmental damage this event has become one of the biggest risk in Iran.

Vulnerability is a logical effect because of the risk of living in hazardous regions and determines the amount of endurablity of the capacity of risk and regeneration. Vulnerability is a complex phenomenon which includes environmental، political and economic-social divisions. According to subsidence risk generation in settlement areas and constructions in Tehran، the risk due to its morphological effects is trivial and it’s necessary to analyze and grade it. Unfortunately because of the missing of the knowledge about this phenomena by the at risk groups and disability to regulate it، the vulnerability includes a wide range involving economic-social and environmental fundamentals. Knowledge about the amount and range of vulnerability in this region can be a proper data base for managers and agents who are working to regulate، control and prevention of disaster. Study area: The study area includes the lands at high risk of subsidence in southern Tehran The approximate area of 64 square kilometers in area 17، 18، 19، and 20 in Tehran taken And mathematical the Is location of east longitude35̊ 35ʹ22ʺ up to 35̊ 39ʹ 39ʺand north latitude 51̊ 22ʹ 92ʺ up to 51̊ 18ʹ 19ʺ. These for study were the following Data: - ENVISAT Satellite radar images of the sensor ASAR the 45-day period in the spring and summer of 2011- Optical satellite images from Landsat TM sensor patch 164 Row 35 On 18/07/2010- The survey data collected from field operations with D-GPS- Documents and reports and library resourcesTherefore، by using of interferometry of radar waves، the rate and value of the subsidence in the studied area have been extracted. Then for generation of the map of the high risk areas، rate and value of subsidence، as an effective factor، delivered to analyzer system in GIS environment. The resulted map involves the cells of the different risk generation factor. In order to evaluation of the vulnerability، spatial distribution pattern of the buildings and the map of the vulnerable areas is considered. according to these information and by using of the field studying the vulnerability of the population، houses and buildings placed in the studied area is considered. Result and discussion، Knowledge of population and human groups’ vulnerability as a tool for prevention of expansion of living in hazardous regions is noticeable. Analysis of vulnerability of population centers which are stored in hazardous regions is a scientific action for providing a proper information basis of vulnerable degree of the risk Occurrence. According to such point of view the analysis of the vulnerability due to geomorphological subsidence hazards in the south of Tehran is noticeable. Extraction of the vulnerable areas showed that 12. 7% of the total area is the most vulnerable، 14. 7% of the total area is the vulnerable، 15. 5% of the total area is with a little risk and more than half (57%) of the area placed in the lower risk. the results proved that the most of the settlements and the related populations are vulnerable. The field studying showed that the most of the buildings are non-engineered which causes that the under construction buildings in the risk.

A number of destruction and environmental degradation is a function of geographic location، climate and land characteristics، morphology، public attitude toward environment، inefficient management، not updated laws، consumerism and unawareness of the true value of energy resources، incorrect site selection of towns and industries، inefficient distribution systems and the things like these. Creation and distribution of environmental crises in several countries generally is the result of inability to balance between developments، environment low attention to the foundations of sustainable development and environmental justice. Considering that one of the most important indexes of the countries is the rate of their community''s preparedness against various types of natural disasters. Most of the world''s countries pay low attention to emergencies and crises in their development programs. Frequently it is common that development planners and crisis ones work separately and this led to imbalances in the planning of the development and crisis. And only a few countries exist that have comprehensive plans and disaster risk management in their development plans which has been given more attention to preparation phase in them and the most attention is given to phase for coping with crisis. Lorestan geographical location is in the way that is receptive to diversity of climate، precipitation، temperature، humidity، mountains، plains and etc. In the same ratio the variety of plant and animal habitat is compatible to fertility status. Environmental hazards phenomena and environment in Lorestan is a consequence of the phenomenon in Lorestan geographical location and human dynamics. Therefore، in this study، natural hazards and environmental risk and crisis management are analyzed by SOWT technique. For evaluating and managing environmental risks many researchers have tried to study and using different methods.

Vulnerability is a term used to show the amount and extent of damage and the losses caused by natural disasters in different communities (social، physical - physical، etc.) is entered. The sensitivity of the environment against the hazards، vulnerabilities it identifies. The vast scope of the damages of natural disasters، especially earthquakes، can be had for desert regions. Therefore in order to prevent further loss and damage needs to be studied in different sizes. A study of nature - a practical and descriptive - analytic study has addressed the issue of Yazd. And the seismic predictions based on statistical methods can give satisfactory results; Study using a quantitative model، µd، TOPSIS and GIS، Excel and SPSS software to examine the issue. Also، in order to reduce the error rate to determine a more accurate forecasts، 50 variables of social indicators - structural analysis and evaluation has been involved. The results show that the µd، model to structural damage in the earthquake of 5 Merkaly almost no or very little damage. However، if more than 7 on the Richter scale of earthquake intensity is more than 50% of the buildings are earthquake-vulnerable zone 2. Social Vulnerability in the districts out of TOPSIS Model 412/0% for the first respectively the second and the 642/0 and 183/0 of the maximum and minimum social vulnerability to disaster areas in the city of Yazd.