Environmental hazards include all kinds of hazards in the environment such as natural and technological or natural and man-made. The natural phenomena such as rains or floods are the normal behaviors of the nature which only when they cause damage to the human life, are considered as hazard. The technological events such as road accidents, air pollution and chemical pesticides are always dangerous to human life. Both kinds of two hazards are produced in the context of human- nature relation. For example if human beings avoid flood prone areas there will be no harm or damage. And if human beings control their waste in the urban areas they will never pollute the city. Thus, this is the human who causes risk and damage to his life. The relation between human and the nature is governed by the thoughts and beliefs of human or in general terms his world perspective and philosophy. It is the human perspective and belief which controls his action at any circumstances. A person who believes in the nature as his mother and supporter of life differs from the one who thinks of nature as a sole source to use and enjoy. The first one gets only his basic needs from the environment, but the second person tries his best to exploit the nature for his benefits. Therefore to understand the intensity and frequency of environmental hazards, we should investigate the mental beliefs of people living in different places. A brief discussion of the historical development of hazards will help us to have a better understanding of the philosophical basis of the environmental hazards. From the ancient times up to around nineteenth century life was very simple and man had been using nature only for his basic needs, there was no consideration of environmental hazards. Hazards were considered only as diseases threatening the human life. But later, especially after the industrial revolution, due to the increase of human population and demands, the use of natural resources was exponentially increased far above the production and recovery of the nature. This process triggered the occurrence and expansion of environmental hazards. The human- nature relation is studied by different scientific fields such ecology, anthropology, and geography from different aspects. The ecologists mostly emphasize on the relationship of individuals with his environment, as the characteristics of environment controls his life. While geography studies the spatial relations between human population and environmental assets. As a result, the philosophical stances of these fields differ substantially. Ecologists want to see whether this relation is dominated by the needs and intentions of man or by the capacity and potentials of the nature. From this point of view three kinds of philosophies were developed including anthropocentrism, biocentrism and ecocentrism. On the other side, geography emphasizes on the spatial distribution of human population on the basis of environmental resources. This spatial relation between human and natural resources is believed to be controlled by the nature or human conducing to the development of two philosophies of environmental determinism and possiblism. Ecological philosophy of anthropocentrism was dominated in the earlier centuries, focusing on the will of human to use and enjoy the nature. In this view, the nature has the instrumental value for human. The result of this philosophy was depletion and destruction of the environment in favor of the human development. But during the twentieth century some philosophers stated that the human does not have the right to harm and damage all living creatures including animals and plants. This view ended with the biocentrism approach. During the second half of the 20th century due to the over exploitation of nature by human, the philosophers and ecologists realized that the human kind in order to possess a sustainable living should not harm any members of the environmental system including even rocks, rivers, soil and etc. This approach developed the ecocentrism philosophy. The main controlling force in these philosophies is the ethical stance of humans. On the other hand, the older geographers believed that it is the nature that controls the human distribution and living conditions. The humans cannot change the natural arrangement of the environment and should limit their activities to the natural allowances. The development of the technology after the Second World War changed this view. Some geographers believed that human can change the environment by his techniques and developed the possiblism. The adoption of this philosophy and the growth of industrial development ended with the deployment and damage of the natural resources. It is clear from the aforementioned discussion that in all cases, the main reason for the depletion and destroy of the environment was lack of ethical considerations in human behavior toward the nature. If the ecologists have come with the ecocentrism, geographers developed the geocentrism philosophy. That is, to save the nature and prevent environmental hazards we, as human beings, should preserve the natural arrangement of resources. We should not disrupt the spatial order of any resources, because it will cause harmful results in the environment. For example eroding the soil will deteriorate the vegetation and cause floods and other hazards. The alteration of spatial order of surface temperature has caused the thermal imbalance and hence global disorder and warming. There is no doubt that the relation of each human should be controlled and put in the moral contexts, but to prevent the environmental hazards an overall effort is needed over the environment which is possible only through the preservation of spatial order of natural resources. Spatial management of land resources is the outstanding example of this philosophy and ethic.
Natural disasters are investigated of various dimensions and consequences of natural hazards. As well, they can become as a repeatable phenomenon in the absence of mitigation systems, and could be caused devastating consequences. Resiliency approach as a basis for reducing the negative effects is taken into account to reduce the impact of natural disasters. Today, the two tourist areas of Cheshmekile (Tonkabon County) and Sardabrud (Kelardasht County) as typical feature of regional tourism planning have important potentials for development of tourism. But in recent years they have repeatedly been invaded by floods so that in some cases the impact of economic, environmental, socio-cultural and physical environment is followed. In economic dimension, flash flood destroyed agricultural fields and rural houses and in socio-cultural dimension it has increased insecurity. And finally, in terms of the physical and environmental aspect, it has created the most damage such as adverse changes in the appearance of the landscape, loss of trees, and destruction of public infrastructure (roads and bridges network). It is an approved hypothesis that rural settlements cannot be moved to the riverbank, but have created a situation that endangered abiding rural settlement. Various aspects such as socio-cultural, economic and administrative highly effect on resiliency. Among them, the role of infrastructures such networks, the location of health care facilities, police stations, fire stations and disaster management offices, communication networks (telephone, Internet) are more important to improve resiliency. This paper seeks to answer the key question that is the infrastructure in promoting resiliency after flooding in the two areas satisfactory? The methodology of the study is objective and analytical analysis is based on the nature and method. The main variables are infrastructures and resiliency. Resiliency as the dependent variable consists of two main components of individual and community resiliency. Required information on the objectives, data integrity and availability has been developed in both library and field methods. In previous studies, library and documentation center is studied. Questions are sorted in the distance range, rated and ranked based on the needs and nature of the research and the knowledge and the education level of the local community. Questions are tested initially and after a measurement of the level of reliability (0.812), which is obtained using Cronbach's alpha. First, to determine the total sample size of villages located in flood risk areas in the two basins 9 villages (50%) were selected. Cochran formula is used to determine sample size. According to Cochran formula for the total population 296 households that included 129 head of households for Sardabrud basin and 167 head of households for Cheshmekileh basin. After the initial survey the collected information is encoded using a statistical software SPSS and then has been processed according to the assumptions formulated. Based on the results of the questionnaire analysis, some indicators, same as access to aid agencies (Crescent) and disaster management center, there were no significant differences between rural settlements such as the two basins distance to the city center is short. The nearest major communication route roads - Branch is located at a distance of 5 km from the city of Kelardasht, but in Cheshmekileh basin there are less than 5 kilometers distance to the main road of the Caspian Sea. That is why the average satisfaction of the local authorities in these areas is much higher than Sardabrood basin. Check out the highlights of each area residents is showed more satisfaction on facilities and services infrastructure in Cheshmekile. Result. To understand the relationship between resiliency and infrastructure used is the correlation coefficient between these two measures 003/0 there is level. This relationship of mutual relations, the improvement of infrastructure in the area with 99% probability of increasing population resiliency against natural disasters (floods) within it. The average calculated for the physical aspects - infrastructure represents the position of the component. Ring roads in northern cities, near airports such as Ramsar Branch, and there are several large medical centers, access to police stations in both basins are made from the perspective of the respondents favored the status of this criterion is to be evaluated. However, among the subset of infrastructure, the roads are better than others. The reason can be attributed to the investment and construction of new networks of communication. In the case of energy network, although the topography of the area is caused that part of the basin, some of villages such as Gavpol, Letak, Drazlat in Cheshmekile basin and Lush, Krdychal and Roudbarak in Sardabrood basin was still stay deprived of the gas network but have favorable drink water and electricity network. However, keeping the population in the rural area is largely dependent on the infrastructure. Resiliency in relation to rural and infrastructural facilities, access to places of temporary accommodation is very important but in this particular field in any of the villages still planning has been done.
Although environmental hazards occur because of natural factors, however, political economy, controlling the sociospatial relations and conditions, also affect centrally the increase or decrease of physical and social vulnerability caused by hazards. In this regard, present paper has put the spotlight on “explaining the role of spatial distribution of social stratification in vulnerability to environmental hazards in the city of Tehran”. This is based on Political Ecology Approach which emphasizes the domination of prosperous social strata on the urban natural-ecological endowments and utilities and marginalizes low-income and inferior social strata. So, the recognition of social strata inhabitation across the city is significant for the analysis of social inequalities and their effects on the vulnerability of environmental and human hazards. The concentration of middle to high class and working and inferior classes has also caused the range of social inequality to increase in the metropolitan of Tehran and this trend per se has transformed Tehran to the spatial reflection of the contrast between poverty and wealth to the greatest extent in the country. Hence, regarding the fundamental role of social stratification and class structure and its evolution in explaining the dynamics of socio-economical relations in the dominant society and the process of urban space production and reproduction, explaining the role of spatial distribution of social stratification in vulnerability to environmental hazards in the city of Tehran is significant and necessary. Vulnerability to environmental hazards has been studied from the physical, biological perspectives, social construction perspective and contingency perspective. The present paper emphasizes the effects of social construction on the production of vulnerability. Scientists think radical and critical geography of space is a kind of social production. They believe that not only urban space, but also the entire space has a social structure and nobody can analyze it thoroughly regardless to the society’s work on the space. Thus in a world under the Capitalist System, urban space represents a reflection of the control and domination of superior social strata (owners of power, wealth and high status, or the owners of political, economic and socio-cultural assets) in its functional zones. This has been appeared in the recent decades, within the literature of hazards and catastrophes and based on “an approach of vulnerability” which has been rested on Political Ecology. The mentioned approach has been concentrated on a series of socio-spatial conditions and political economy which shapes the hazards and catastrophes. Some of the effective social conditions in shaping the hazards and catastrophes and their amounts of vulnerability depend on the racial, ethnic and class characteristics. Racial, class, ethnic and political economy analyses, which dominate their social ties, are considered as part of understanding knowledge system of hazards and catastrophes. Since this causes detecting the role of political economy of inequalities and racial, class and ethical processes and the marginalization caused by it, in the emergence of hazards and exacerbation of catastrophes and crises impacts. To use job structure means to emphasize concrete class structures, according to which an image of social inequality can be offered. Thus in present study, for structure determination and main composition of social stratification in Iran and Tehran “Structure Determination and Composition of Social Strata Model” was used. According to this model and with the use of data from matrix tables, major occupational groups and occupational situation have been classified in 5 classes superior strata, traditional middle strata, new middle strata, working and inferior strata and farmers. The data were prepared and analyzed by ArcGIS and Ms Excel softwaares. During the last century, uneven development process of the country was in favor of the Tehran and superior strata and powerful institutions located in this city. Regarding the processes and relations emerged from political economy of space and political ecology of Tehran, social strata inhabitation of Tehran has been in compliance with environmental capacities raised from topographic and microclimatic distinctions and ecological endowments. The findings of present paper also indicate physical and social vulnerability changes caused by probable hazards related to the general pattern of social strata inhabitation in north-south geographical direction. Spatial distribution of populated blocks in 1996, for which more than 30% of their inhabitants were “senior managers and experts” and “manufacturing jobs employees and laborers”, indicates the above mentioned issue and clearly show the poverty (old poor neighborhoods) and wealth (expensive and rich neighborhoods) spatial centers. In addition, according to the supporting studies on Tehran Comprehensive Plan, most of old urban tissues are in central and southern regions. Also according to the International Seismological Research Agency (JICA), the mentioned regions would be the most vulnerable in the Tehran probable earthquakes. Therefore, it can be said that findings and results of the present study indicate the determining place of political economy of space and urban political ecology and also the fundamental role of social stratification and class structure for recognition, analysis, explanation and understanding of the urban development challenges and problems. Hence, this is impossible to reduce social and physical vulnerabilities caused by natural and human hazards, particularly in the poor neighborhoods, regardless of political economy of space mechanisms and reduction of the gap and even urban development.
Thunderstorm is one of the most severe atmospheric disturbances in the world and also in Iran, which is characterized by rapid upward movements, abundant moisture, and climatic instability. Since this phenomenon is usually accompanied with hail, lightning, heavy rain, flood and severe winds, it can cause irreparable damage to the environment. Investigation of spring thunderstorms has a great significance regarding the irreparable damages can cause by them and also because of the higher frequency of this phenomenon in the spring and the necessity for preparedness and disaster mitigation actions. To identify the locations of the major thunderstorm risk areas, the entire country with an area of 1648195 square kilometers, which is located between the 25°-40° north latitude and 44°-63° east longitude is considered. Spatial distribution of the occurrence of hazardous spring thunderstorms was analyzed using a series of monthly thunderstorm frequency data obtained from 25 synoptic stations over a 51-year-long period (1960-2010). Ward's hierarchical clustering and Kriging methods were used for statistical analysis. Initially, total number of thunderstorms in April, May and June were considered as the frequency of occurrence of thunderstorm in different stations in the spring. Measure of central tendency and dispersion which consists of the sum, minimum, maximum, range and coefficient of variation, standard deviation, and skewness were used to clarify the changes of thunderstorms and to determine the spatial and temporal climatic distribution of spring thunderstorms. An appropriate probability distribution function was chosen to determine the distributions of the data. Due to the large volume of data and the uneven distribution of stations, cluster analysis and kriging methods were used to classify different regions into homogeneous groups for zoning and spatial analysis of spring thunderstorms, respectively. The statistical characteristics of spring thunderstorms were reviewed and fitted with a 3-parameter Weibull distribution. Regions considered for this study were classified in four separate clusters according to the simultaneity of thunderstorms in the spring. After zoning, it was found that the highest rates of thunderstorm took place in the northwest and west of country. The northeast of Iran has the second highest number of thunderstorm occurrence. The least number of thunderstorm event had happened in the central and southern half of the country. According to the descriptive statistics parameters, maximum number of thunderstorms occurred in May.. Based on the results of the cluster analysis, there is a similar trend in the central and eastern regions, the rest of the country was clustered into five distinct homogeneous regions, including the northwestern, western, southern, northern, central northern and northeastern regions. Zoning results indicate that the highest number of the occurrence of this phenomenon in the country is concentrated in the northwestern and western regions. Higher frequency of occurrence of thunderstorms in the northwestern and western regions may be attributed to local topographic conditions like high mountains, orientation of the terrain, solar radiation on slopes and existence instability conditions, hillside convection, the presence of water resources and specific climatic conditions in these areas. In addition, as a result of a continuous surface obtained by the method of interpolation with the least amount of systematic error and also the use of correlation functions for recognizing the spatial structure of the data and estimating the model error when using the Kriging method, the weights are chosen in order to have a more optimized interpolation function. Also the cluster analysis may significantly reduce the volume of operation without affecting the results and will help in finding a real band due to more appropriate classification of different geographic areas with greater spatial homogeneity and minimal variance within the group. Based on the results of the spatial analysis, it is clear that Kriging and Ward cluster analysis methods are appropriate for thunderstorm zoning and classification of different regions according to occurrence of thunderstorm, respectively.
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.
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.
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.
Tehran, in the south of Alborz Mountains, is faced with three types of weather risk, weather risk caused by geography, climatic risks caused by air resistance and weather risk due to global warming. The aim of this study is to examine the three types of risk in Tehran. The method of this study was to evaluate the changes of synoptic factors that affect global warming and urban development. In order to detect the height changes of 500 hPa two 5-year periods including 1948 to 1952 and 2010 to 2014, were studied.
The results showed that changes in heights of 500 geopotential, there was an increased risk in the city of Tehran. The effect of climate change in recent decades, increased the stability of air in Tehran. Human factors in the formation of heat islands, increase LCL height and density of the air balance is transferred to a higher altitude. Changing urban wind field, atmospheric turbulence intensified, exacerbated thermodynamic gradient, fat and refugee cyclones, heat island effect of the city.
Thermal stability in the warm period will appear. The thermal stability of all levels of lower, middle and upper troposphere was intensified. Thermal stability couraged the development of subtropical high pressure in the area. With the arrival of the atmospheric pressure during calm and humid days the stability and pollution were increased. Negative vorticity from early June developed the intensive high pressure over the region. Compare the conditions of the two study periods showed that : the height of the high pressure was 100 meters higher than the second period. The number of days of intensified subtropical high increased during the second period. The high pressure has moved to the northern areas during the second period. This change in the subtropical high pressure increased the dry periods motivating the loss of vegetation. Heat island effect was increased as well. More than 90% of the temperature inversions occurred at an altitude of less than 500 meters in both warm and cold periods of year. Wind direction at both stations has shown that the establishment of any pollutant source in the West of Tehran will increase the pollution.
The term "Game GIS” implies to real spatially enabled games in which a special part of the world is virtually simulated, represented and managed. In fact, game GIS is an integrated system consists of video games and geographical information systems, aimed to simulate and representing spatially enabled environment. The achieved result of implementing a game GIS service can be exploited before a crisis for wise designing of a city and diminution of the aftermath casualties. As the decision making process plays the key role to reduce the losses, the need arises for using the models as much as close to the reality. By this, it is possible to use the virtual world in in the form of a game rather than experiencing the real world with real wounded and killed persons in. This enables us to recognize and manage a test environment for promoting the managing the real environment of a city during and before a natural hazard disaster like an earthquake. The game GIS may be counted as a service for sharing and dissemination of spatial information as well as online GIS to have a visual and synoptic management of the earth plant facing various disasters. The current research is aimed to design and implement a software architecture for an earthquake game in Tabriz city (Iran).
The study area is district 10 of Tabriz located within a fault zone. According to field surveys, 82.1 percent of buildings in the study area may be vulnerable against earthquake in terms of the quality of building construction.
Methodology of the research to design, program and implement the game GIS service are undertaken as the following processes: data collection, database creation and software production.
The collected data includes master plan maps of the district 10, building quality, number of floors, building façade materials, age of building, street network (adopted from the master plan of Tabriz) and population of each parcel. Also, some regions are assumed as hospital, relief-rescue center and treasury money.
To design the software, 2D environment of MapControl and for implementing the game into the 2D environment, ArcEngine of ArcGIS have been exploited. The mentioned engine gives us possibility to use of analysis and modelling capabilities as much as closer to the ground reality which are compatible with available geometry of the terrain (Amirian, 2013, 17-19). The MapControl is a framework in which the map and game area are displayed. Symbology is used to show the persons as well as equipments. Briefly, the stages undertaken during the current research can be explained as the following:
After that, the conceptual architecture of the software has been designed based on the scenario.
The game GIS services has been designed with 6 different classes offer numerous functionalities responsible for displaying program commands and different views of the game. Finally, the service is designed and implemented in a real schema for crisis management application. The resulted game is played in 4 stages. In the first stage, the player starts with a 5 Richter magnitude earthquake and ends while the player gets to 8 Richter. The designed software simulates the destruction rate of buildings based on the influential factors, wounded transfer routing and rescue operation. The game player gains credit according to his quickness and agility. The player would go to the next stage with one Richter magnitude higher, if gains enough credits during each stage. The result of the current research as a Game GIS service, can be used in earthquake simulation happens in various magnitudes for management of decreasing the effects of earthquake, quick reaction, maneuver and education. Considering the achieved results, designing and performing the game GIS service over the web based on open source technologies rather than being desktop and commercial service, can be suggested as a new research frontier for the future researchers.
The process of urbanization and development in high-risk areas such as river banks has increased the vulnerability of urban communities to environmental hazards. The banks of Khoshk River in Shiraz is one of these areas. These hazards are two parts : hazards resulted from river and waterways erosion (destruction, transportation and sedimentation) and the hazards resulted from floodings over the surrounding urban areas.
In order to prepare the literature review for this study, the various books, theses and articles were applied. Also, in order to determine the spatial position of this section, the Satellite Images and Google Earth pictures were used. The Global Positioning System (GPS) was also applied for the field observations such as collecting spatial data, extracting the kind of formations, Geological structures and faults. ArcGIS and Global Mapper 16.2 were also used for data processing and mapping.
The geomorphological hazards in Khoshk River bank were evaluated in two parts:
The evaluation of longitudinal profile in the river indicates that when the stream is entered to plain, the water moves with more speed because of faults and high steepness over the Drake alluvial fan. One indication of this process is the presence of coarse sands and angled gravels. In this part, the erosion of riverbank is much higher than the erosion of river bed. In this section, the longitudinal profile of the river has a regular trend of concave and convex sections due to the erosion in convex parts and sedimentation in concave parts. In addition, there is a balance between deposition and digging process. The erosion is very intensive in regions where arc meander is close to the flooding plain of the bank and causing the destruction of all facilities.
The longitudinal profile in the river indicates that the height and slope of river has been reduced from North West to Maharloo River. The average slope of the river is 2.40%.
In order to determine the role of flooding in creating risks for Shiraz, the floodwater discharge data were collected from Regional Water Organization. Furthermore, in order to understand the role of maximum discharge values, various experimental relations were used in the basin. The un- ordered development of urban areas especially in the north west, destruction of natural areas intensified the amount of runoff and reduction of vegetation cover.
The pick values of maximum discharges in Khoshk river with the return periods of 50 and 100 years waere estimated 115m3/s to 131.4m3/s respectively which may result in overflowing of water on the streets. The human factors include the construction of bridges on the river, fencing river with stones and construction of beach, construction of bypasses for public transportation and reducing the traffic in the riverbed and trespassing to the river bed in Shiraz caused the overflowing of water from the river. The last floods in Shiraz occurred in 1987 and 2002 that caused major losses to the houses and commercial places close to Khoshk River. In order to analyze parts of river that are close to the town and have more important influences on the hazards and disasters, the satellite images of khoshk river basin in the town were taken and the river was classified in three sections with regard to risks level, river morphology and river classification based on its hazards for close areas as high risk (Maali abad Bridge limits to Fazilat Bridge and Sardkhaneh Bridge to Maharloo River), low risk(Tange sorkh to Maali abad Bridge) and medium risk (Fazilat Bridge to Sardkhaneh Bridge).
Natural disasters is one of the main challenges for developing countries, which not only cause death and emotional pain and suffering of survivors, but greatly affecting development. Reduction programs and prevention of disasters, including policies that countries to increase community capacity in disaster, are followed to improve the effects of these disasters. One of the risks that affect Iran, is flooding. Iran has a very high risk of flooding, which in most years, about 70% of annual credit plan is paied to reduce the effects of natural disasters. Floods in recent years has left a lot of damage in many parts of Iran. Because the flood event and can not be prevented, but we can assess the resiliency and vulnerability of risks to reduce the effects of flooding greatly. Planning in disaster management process can reduce the risks of accidents and improve the resilience. Thus, how and by what means we can increase the capacity of society to accept a certain level of risk is very important. In recent years, many researches, focused over concept of resilience and disaster risk reduction policy. This research study area is the Nekarud basin in Mazandaran province. Population growth and unethical uses of Nekarud and natural resources, humans and their facilities, infrastructure and natural resources of the basin are vulnerable. The aim of this study was to evaluate the resiliency and identify strengths and weaknesses in the flood affected villages Nekarud margin is based on random sampling of villages (8 villages) have been affected by floods in recent years, were selected. The research method is descriptive and analytical study of its nature. The aforementioned villages to assess the resilience, the four dimensions of economic, social, and institutional infrastructure based on the location of the axis (DROP) provided by Cutter and his colleagues in 2008, was used. According to the surveys and the results obtained, it can be stated that the model DROP, because of the location-based (geographic), and the integrity of the elections aspects and indicators to measure and assess the resilience of settlements is a good model. The dimensions considered to measure resilience include: economic, social, institutional and infrastructure. After determining the dimensions required components and indicators research, scientific references were identified by the study, questionnaires were prepared. Secondly, the need of the rural sample in the form of a questionnaire, collected and analyzed after coding in SPSS. The findings of the study showed that the settlements are in a different situation in terms of resilience in different dimensions. The economic resilience for the total sample is 8.96. The amount of this variable for Zarandin-e Olya, Zarandin-e Sofla, Abelo and Kuhsarkadeh rural settlements is higher than the average whole.
Hazard is potential source of harm or a situation to create a damage. So identification of zones exposed to hazards is necessary for planning or land use planning. But this situation becomes more critical when they appear at the population centers. So applying the principle of passive defense based on environmental capabilities is unarmed action that caused the reduction of human resources vulnerability, buildings, equipment, documents and arteries of the country against the crisis by natural factors such as drought, flood, earthquake, etc. Considering the possible occurrence of such risks in population centers, ready to deal with what is known unpleasant and undesirable consequences is necessary. On this basis and given the importance of population centers in Helle and Mond basins, in this study, the authors tried to analyze the Rain hazards of drought and flood.
The study area,Helle and Mond basins, with about 21,274, 47653 km2 area, respectively are located in the south of Iran. The Helle basin approximately is between 28° 20'N and 30° 10'N latitudes and between 50° E and 52° 20'E longitudes and Mond basin is between 27° 20' and 29° 55' latitudes and between 51° 15' and 30° 27'E longitudes.These basins are located in sides of a massive sources of moisture, Persian Gulf.
In this study, data from 23meteorological and synoptic stationsstations, during aperiod of20 years (1992-2011)in northern region of the Persian Gulf (Mond and helle basins)were used to calculate Standardized Precipitation Index (SPI). The data were collected by the Iranian Meteorological data website (http://www.weather.ir). The SPI is primarily a tool for defining and monitoring drought events. This index may be computed with different time steps (e.g. 1 month, 3months, 24 months). The SPI is defined for each of the above time scales as the difference between monthly precipitation (xi) and the mean value ( ), divided by the standard deviation. To assess flood risk zones, the flood, annual evapotranspiration, cities and populations centers layers were collected in Helle and Mond basins position. The annual precipitations and the SPI maps were drawn by Geostatistics, Kriging. It also the flood and annual evapotranspiration layers were weighted by Euclidian distance method, separately. Finally, all layers are weighted by AHP and fuzzy-linear methods (descending and ascending linear function) into vulnerable layers. The final map of vulnerable areas with flood and drought high risk was drawn based on the algorithm of linear-Fuzzy in a raster format.
According to the results, eastern, north eastern and south eastern part of Mond basin had high annual precipitation. Based on this result, it said that these parts of study area were known the least dangerous areas of vulnerability. The results also showed that with passing of the western regions and going to the center of the study area the annual rainfall have been added over the years. Kazeron, Chenar Shahijan, Firouz Abad, Borm plains and some parts of Khane Zenyan and Dash Arzhan are cities located in this regions. Low latitude, Proximity to the warm waters of the Persian Gulf, low annual precipitation and high temperature causing evaporation and inappropriate environmental conditions in Boushehr province and some coastal cities such as Genaveh, Deilam, Boushehr, Baghan, Lar and Khonj. Accordingly, west, north west, south and south west regions in Helle basin were located in extreme vulnerability zone with a loss of annual rainfall for drinking and agricultural production and poor nutrition underground aquifers.
Trees in urban areas have survived in a wide variety of conditions and constrains, whether developing in natural or manmade habitats. Due to environmental constrains and stresses, urban trees rarely achieve their biological potentials. Indeed, some of trees, in small groups, could excel in terms of age, biomass structure and dimensions in urban areas. In definition, tree hazard includes entirely dead or dying trees, dead parts of harmed live trees, or extremely unstable or unsteady live trees, which could be in result of structural defects and disorders or other factors that have the high risk to threaten the safety of people or property in the event of a failure especially in urban green spaces. Although the pruning or other rehabilitation and mitigation program of trees is known as the one of the principal domains of green space management, it is still includes shortcomings in terms of models and methodologies to classify or prioritize hazardous trees which need to be treated timely. The main objectives of this study were to: (1) model old Sycamore failure hazard in urban green spaces to elucidate the general and defects tree factors affecting on failure hazard; (2) prioritize the impacts of model inputs (general and defects tree factors) on tree failure hazard using model sensitivity analysis and (3) determining the trend model output changes in respond to model variables changes.
The following types of data (target trees characteristics) were solicited for each target tree: (1) General features: Tree Height (TH), trunk Diameter at Breast Height (DBH), Butt Diameter (BD) at ground surface and Vertical Length of Crown (VLC) were calculated from measured girth. Crown Spread (CS) was measured as the average of two diameters of projected drip line of the tree canopy.
(2) Tree defects: Detailed evaluation of individual trees was made according to 6 key physical defects, namely Internal Decay (ID) in percent, Length of Cracks (LC) in m, Crown Defoliation (CD) in percent, and Degree of Leaning (DL).
(3) Sycamore failure hazard classification: Sycamore Failure Hazard Risk (SFHR) classification was the probability that an entire tree, or part of it, will break and fall within the first or second year after study. Considering results of tree regular monitoring after two years, the following classes of tree failure hazard were determined. 1. Extremely Hazardous: Tree failure in the first year. 2. Semi-Hazardous: Tree failure in the second year.
ANN has been recently developed for data mining, pattern recognition, quality control, and has gained wide popularity in modeling of many processes in environmental sciences and engineering. ANN learns by examples and it can combine a large number of variables. In this study, an ANN is considered as a computer program capable of learning from samples, without requiring a prior knowledge of the relationships between parameters. To objectively evaluate the performance of the network, two different statistical indicators were used. These indicators are Mean-Squared Error (MSE), Mean Absolute Error (MAE), and coefficient of determination (R2).
In this study, the year of Sycamore failure in urban ecosystems is evaluated using tree variables and artificial neural network to determine the most effective tree variables in SFHR in urban green space. Various MLFNs were designed and trained as one and two layers to find an optimal model prediction for the SFHR and variables. Training procedure of the networks was as follows: different hidden layer neurons and arrangements were adapted to select the best production results. Altogether, many configurations with different number of hidden layers (varied between one and two), different number of neurons for each of the hidden layers, and different inter-unit connection mechanisms were designed and tested.
In this research, 200 trees were totally selected, then general and defects tree variables were recorded in urban green space. Considering the aim of study, which is discovering the relation between general and defects tree variables with SFHR class for modeling, the year of tree failure, was recorded.
In the structure of artificial neural network, general and defects tree variables were tagged as inputs of artificial neural network and SFHR class was tagged as output layer. Considering trained networks (the structure of optimum artificial neural network has been summarized in Table1), Multilayer Perceptron network with one hidden layer and 4 neurons in layer created the best function of topology optimization (Table2) with higher coefficient of determination which equals 0.87 for class 1 and 0.9 for class 2. Sensitivity analysis respectively prioritizes Crown Spread (CS), Vertical Length of Crown (VLC), Degree of Leaning (DL) and Butt Diameter (BD), which effect on SFHR in class1 (Fig1) and class 2 (Fig2).
The determined procedure of SFHR changes with CS changes in the region declares SFHR increase nonlinearly with an increase in CS. The determined procedure of SFHR changes with VLC changes o declares that SFHR increase nonlinearly with an increase in VLC of tree. The determined procedure of SFHR changes with DL changes in the region declares SFHR increase nonlinearly with an increase in DL. The determined procedure of SFHR changes with BD changes o declares that SFHR increase nonlinearly with an increase in BD of tree.
Nowadays, artificial neural network modeling in natural environments has been applied successfully in many researches such as water resources management, forest sciences and environment assessment. The results of research declared that designed neural network shows high capability in SFHR modeling which is applicable in green space management of studied area. Sensitivity analysis identified the most effective variables which are influencing SFHR. So, to identify hazardous trees in study area, we should pay attention to the CS of Sycamore trees as the variable with high priority in determination of SFHR. We believe that, in hazardous trees management in urban green spaces, we should pay attention to some modifiable factors of tree, which are CS and VLC, by timely tree pruning. We suggest urban green space manager to run SFHR model, for tree stability assessment, before decision making on hazardous trees.
Probability of earthquake hazard | Distance to fault lines | Relative area | |||
Active Faults | Passive Faults | Active Faults | Passive Faults | ||
Very low risk | 0-20 | 60-76 | 32-42 | 7.29 | 1.42 |
Low risk | 20-40 | 45-60 | 24-32 | 13.82 | 3.96 |
Medium risk | 40-60 | 30-45 | 16-24 | 16.66 | 8.13 |
High risk | 60-80 | 15-30 | 8-16 | 21.51 | 22.04 |
Very high risk | 80-100 | 0-15 | 0-8 | 40.72 | 64.45 |
sum | - | 100 |
Probability of earthquake hazard | urban Settlement | Population (2011) | Relative population frequency (percent) | ||||
Active Faults | Passive Faults | Active Faults | Passive Faults | Active Faults | Passive Faults | ||
Very low risk | 0-20 | 3 | 1 | 135846 | 17106 | 1.14 | 9.07 |
Low risk | 20-40 | 6 | 4 | 86133 | 144021 | 9.62 | 5.75 |
Medium risk | 40-60 | 10 | 8 | 739095 | 754968 | 50.43 | 49.37 |
High risk | 60-80 | 14 | 18 | 380908 | 273137 | 18.24 | 25.44 |
Very high risk | 80-100 | 18 | 20 | 155188 | 307938 | 20.57 | 10.37 |
sum | 51 | 1497170 | 100 |
Probability of earthquake hazard | Rural Settlement | Population (2011) | Relative population frequency (percent) | ||||
Active Faults | Passive Faults | Active Faults | Passive Faults | Active Faults | Passive Faults | ||
Very low risk | 0-20 | 162 | 42 | 54240 | 30236 | 5.51 | 3.07 |
Low risk | 20-40 | 379 | 147 | 183718 | 92018 | 18.68 | 9.35 |
Medium risk | 40-60 | 481 | 291 | 255412 | 176183 | 25.96 | 17.91 |
High risk | 60-80 | 553 | 766 | 245392 | 340448 | 24.95 | 34.61 |
Very high risk | 80-100 | 1350 | 1679 | 244942 | 344819 | 24.90 | 35.05 |
sum | 2925 | 983704 | 100 |
In Iran, there is a general risk of runoff and flood, and since this country has a dry to semi-arid climate, its predominant rainfall is not evenly distributed in terms of time and place. Routine runoff at the earth's surface can lead to risks such as groundwater abatement, social issues such as population migration, erosion and loss of soil fertility, sedimentation in reservoirs and water quality in rivers. Also, damage to the agricultural sector, subsidence, the destruction of residential buildings and the reconciliation of the urban, rural and nomadic order are all examples of controversy about the risks that runoff and flooding are due to. The severity of these hazards in the Afje watershed is due to the geographical location, the specific climate, geology and pond factors, and a large volume of flooding every year causes the destruction of residential areas, agricultural lands and many financial and financial losses.
In this research, data collection was carried out through library and field resources. The main tools of this research were topographic map of 1: 25000 which was used by GIS software for the separation of layers and determining the boundaries of the basin; Land use maps and user data and hydrologic groups of the study area were also used to estimate runoff height using curve number method and Arc-CN Runoff instrument. Then Arc-CN Runoff tool was used to prepare layers and curve number map (CN). Finally, the runoff height of the studied basin was prepared in the GIS software.
Soil Hydrology Group: According to the studies, in terms of breadth and extent, the Hydrologic Groups C has the largest area with relatively high runoff potential. By matching the map of Hydrologic Soil Groups and the mineralogical units of the basin it can be stated that the green mass tuff and thick conglomerates are in the hydrologic group D, and the thick layers of green tuff, marl and sandstone in the hydrologic group C and the rocky layer of limestone in The hydrological group B is located.
Land use: The hydrological status of the land and types of uses in the Afje watershed basin are as follows. Most of the catchment area is covered by medium-sized meadows, which comprises 53.77% of the basin area and is located in the hydrological group C with relatively high potential of runoff production. The rock outcrops are in the next rank, which is in the hydrological group D.
Runoff curve number (CN): Land use maps and soil hydrologic groups were combined and extracted for each curve number range (CN) and CN map was prepared. The Afjeh basin has a curtain number of 66 to 100. The highest value of the curve number is 100, which is related to the outflow of the Afjeh watershed basin, which is practically inert, so all precipitation becomes runoff. The Afjeh basin has a curtain number of 66 to 100. The highest value of the curve number is 100, which is related to the outflow of the Afjeh watershed basin, which is practically Impervious, so all precipitation becomes a runoff. In fact, the curve number 100 in stone is 5.59 square kilometers from the area of the Afjeh watershed. But gardens and Agricultural land have the lowest CN (curve numbers 66 to 77) in the Afjeh basin, and include 4.53 square kilometers of basin area. Therefore, the lower parts have a lower CN than the upstream of basin.
The runoff height in the four seasons was calculated based on the daily precipitation values occurring at mentioned times.
Based on the average daily rainfall of spring with a value of 10.79 mm and runoff classification, in a small part of the gardens in catchment area due to high permeability of the soil, 2.54 mm of precipitation has become runoff, although it is due to stone due to The Impervious of the surface, 10.66 mm of precipitation, turned into runoff.
According to the studies carried out and according to the potential maps of runoff production in the Afje watershed, in the garden with the value of the curve number 66 and daily precipitation (for example, in the winter with a rainfall of 4.04 mm), the runoff height is 0.76 mm And the peak of discharge of 0.47 cubic meters per second And has the lowest runoff potential. In winter, the upstream sediments of the basin with curve number 100, runoff height of 3.81 mm and peak of discharge of 2.65 cubic meters per second and almost all rainfall becomes runoff. Therefore, the shortage of water resources, the presence of dry and semi-arid climates in the country and the achievement of sustainable development leads to the optimal use of water resources.
keywords: hazard, Arc- CN Runoff, GIS, high runoff, catchment Afjeh
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