Typology and spatio-temporal analysis of environmental hazards in Northern Khorasan province

Environmental hazards cause great human and financial damage to the people of Northern Khorasan province every year. In this research, while introducing different types of environmental hazards in different parts of Northern Khorasan, we aim to classify their issues and problems and to specify the time calendar of each in order to prevent possible damages and crises.
 Unfortunately, so far no research has been done so far that typologically and spatially-temporally analyzes all environmental hazards in different parts of the province. The scope of research includes North Khorasan province. This province with an area of ​​28434 square kilometers and a population of 863092 people is limited to the Republic of Turkmenistan from the north, Khorasan Razavi province from the south and east, Golestan province from the west and Semnan province from the southwest. This province occupies 1.7% of the area and 1.08% of the population of Iran.
Research materials in this research include: 1- Library resources such as books, articles, dissertations, reports and statistics to extract information on the subject under study, 2- Visual documents including satellite images, Aerial photographs, topographic maps and geological thematic maps. This research has been done by descriptive-analytical method and has been described, analyzed and evaluated based on research in library resources and field research. Due to the importance and incidence of Covid-19 disease, in order to assess its risk in the last three weeks ending August 21, 2020 in the townships of the province, first the adjusted incidence rate in the last week (AIRW1), the penultimate week (AIRW2 and two weeks ago (AIRW3) was calculated and then using the relevant equation, the status of each city in terms of white, yellow and red was determined. Regarding the risk of frost, long-term statistical data of minimum temperature of synoptic and evaporative stations of Bojnourd, Asadli, Aghmazar, Resalat, Shirvan, Cheri, Khosh, Noshirvan and Jajarm were used on a daily scale.  To determine the time of onset and end of glaciation, the days were converted to Julius calendar and Minitab and ArcGIS software were used to draw graphs and maps of temporal and spatial distribution of the beginning and end of glaciation.
 Environmental hazards in North Khorasan, according to geophysical trends, environment and formation factor, include natural and human hazards. Natural hazards of this province include 4 general categories of geological, atmospheric, hydrological and biological hazards. Brucellosis (tuberculosis), tuberculosis, hydatid cyst, leishmaniasis, viral hepatitis and infection in the elderly are among the most common infectious diseases in North Khorasan. In addition to the diseases mentioned, kidney stones and cancers (esophagus, stomach and prostate) have significant statistics. The chronological symmetry of cCompilation of the article with the outbreak of Covid-19 disease and the arrivalturning of North Khorasan province in the red situation, made it necessary to address itmentioned issues. In total, from the beginning of March 2020 to the end of August 2020, 8800 positive cases of Covid-19 disease have been registered in the province,. Wwhich are in between the Bojnourd township with a total of 4527 cases, the highest, and Garmeh township with a cumulative frequency of 179 cases, have the lowest number of patients. The townships of Bojnourd and Shirvan with a score of 5.58 and 4.26 respectively have a red status and the highest risk and the townships of Jajarm and Esfarayen with a score of 1.29 and 1.88 respectively have a yellow status and the lowest risk.
Intentional or potential human hazards in North Khorasan Province have been limited to widespread fires and some civil unrest arising from specific points to upgrade the settlement hierarchy from rural to urban or gain township center and .... . Ethnic disputes, group conflicts, technological failures due to ammonia gas leakage in Bojnourd Petrochemical Company, exit of fine dust from Bojnourd Cement Factory, fire risk of fuel tanks of National Petroleum Products Distribution Company in Bojnourd and other cities of the province and road accidents, they areSome one of the most important possible unintentional and  occurredand occurred human hazards in the province include ethnic disputes, group conflicts, technological failures due to ammonia gas leakage in Bojnourd Petrochemical Company, exit of fine dust from Bojnourd Cement Factory, fire risk of fuel tanks of National Petroleum Products Distribution Company in Bojnourd and other cities of the province and road accidents.
From the beginning of 1396 2017 to the end of April 13992020, 67 natural hazards including flood, frost, drought, lightning, hail, snow and severe blizzard, shower, damage earthquake, storm, landslide and fall occurred in the North Khorasan province, totaling 18343001 million Rials have damaged agricultural sectors, infrastructure, government and public buildings, residential, commercial, industrial, educational buildings and vehicles. The highest prevalence was related to flood, hail and frost, respectively. The frequency of flood and hail indicates an increasing trend in this statistical period. The total damage from the beginning of 1396 2017 to the end of April 1399 2020 indicates that the townships of Maneh and Semelghan, Bojnourd and Shirvan without taking into account the frequency of hazards, population size and area, respectively are the most vulnerable and the townships of Garmeh, Jajarm and Raz and Jargalan, respectively they were the least damaged townships. In terms of the extent of the affected areas and their importance, the frost every year causes a lot of damage to gardeners and farmers in North Khorasan. Frostbite in this province comes in two forms, early and late. Studies have shown that the geographical distribution of the beginning and end of glaciation in North Khorasan province more or less follows the topographic situation of the region. The frequency of damage earthquakes indicates the relative continuity of tectonic movements in the seismic state of North Khorasan. This state, which includes the sedimentary-structural zones of Kopetdagh-Hezarmasjed and Aladagh-Binalood, is affected by the compressive movement of the Turan and Central Iran plates. The “Landslide” slope process is another common hazard in North Khorasan, which is affected by the lithological conditions of its formations, especially the sensitive and slippery formation of Shurijeh (Ksh).
Due to the number of dead and injureddead, injured, and damaged housing units, Bojnourd, Raz and Jargalan, Maneh and Semelghan townships were the most dangerous and Farooj and Garmeh townships were the least dangerous townships in the province against floods and earthquakes. Regarding the time calendar of hazards in the province, some hazards such as earthquakes and technological failures are not limited to a specific time, and upside down, some such as flood, plant disease, hail and lightning occur at specific times.
 The results show that geographical location, environmental conditions and spatial planning system make the occurrence of environmental hazards in Northern Khorasan province inevitable and different regions of this province damage from 51 environmental hazards in the form of 4 general types of natural hazards includes geological, climatological, hydrological and biological hazards and two intentional and unintentional human hazards. This situation requires increasing the safety factor of habitats and activities and modifying and changing the methods and instructions by the relevant agencies to deal with these unexpected events. Harmonization of farmers' lives and activities with frost conditions and geographical compatibility with the Corona virus is suggested as the best biological solution.