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Fatemeh Razzaghi Borkhani, Ahmad Rezvanfar, Syed Hamid Movahed Mohammadi, Syed Yousof Hejazi,
Volume 4, Issue 3 (9-2017)
Volume 4, Issue 3 (9-2017)
Abstract
Agricultural development depends on increasing production and productivity and reducing risks threatening the agricultural sector and in the shadow of extension risk management that can be prevented of wasting and damage to agricultural crops and the provision of necessary domestic agricultural production, also providing export and currency-made to advance the country's development goals. Pay attention to the strategic location of Mazandaran in citrus products, natural hazards that threaten citrus production each year in the economic development, production and exports and providing sustainable livelihoods to farmers affected negatively. Agriculture and in particular the subdivision gardening, due to dependence on weather conditions, the brunt of climate change is undergoing, horticulture stable on long-term behavior growers to ensure the stability and productivity of the land in the future is created and the expectations and concerns of the community intended to provide a food healthy and security to protect the environment and natural hazards reduction is concerned.
The main purpose of this study was to investigate Mechanisms of Reducing Natural Disasters and Risk Management to Sustainable of Citrus Gardens in Mazandaran Province. The Population consists of all citrus farmers in the villages of 12 counties of Mazandaran province, a sample of 290 farmers was selected by using proportional random sampling method among 122361 citrus Orchard men. Data were collected by means of a questionnaire. The Validity of questionnaire was determined through sustainable agriculture experts of Mazandaran County and some faculty members at the University of Tehran, Department of Agricultural Extension and Education, Agricultural Management and Development. The reliability was found to be acceptable. Diagnostic validity by using an average variance extracted (AVE) and reliability by using Cronbach's alpha and composite reliability (CR) were confirmed. To explain the mechanisms Confirmatory Factor Analysis (CFA) was used to modeling the structural equations using LISREL software, version 8.80.
According to the results of the ranking factors related to the mechanism in dimensions, "supportive - credit", "environmental - spatial", "socio-participation", "knowledge-awareness", "infrastructure-institutional "," educational –informational" and "economic factors" respectively were mostly mechanisms and strategies based on factor coefficient. Among the credit-supportive, "insurance" has had the most important role in the structure of credit-supportive factor, thus, according to the regional agricultural insurance and damages in the event that the actual performance of the target area is less than the guaranteed performance is a good solution. One of the major goals of sustainable agricultural systems is decreasing vulnerability and improving sustainable livelihoods in rural people. Therefore adoption of GAP technologies has emphasized to increase elimination of pest with minimum impact on the environment, human health and access to sustainable agricultural development, (achieve to environmental, economic and social sustainability) as well as attention to the sustainability of on-farm activities to certain safety and quality of food and non-food agricultural crops. According to the study, understanding and awareness of farmers to improve skills and farming and horticulture management techniques to reducing natural disasters and risk management and expand the participation of farmers in risk management, to develop processing and packaging industries, convenient and refrigeration practices for storage and preservation of agricultural and horticultural crops, in addition to communication channels network through demonstration farms, farmer field schools, workshops, field days, meeting, SMS, and information and communication channels carried by ICT as necessary solutions recommended. This Provides Information and knowledge share among orchardist and strengthening local associations and with each other. This process helps them to increase their awareness about mechanisms of reducing natural disasters and risk management to sustainable of citrus gardens and find positive attitude toward it. This output complete sustainability goals of agriculture through improving social sustainability. In order to access growers to timely sales service products, the establishment of a new extension system based on an available market with up to date and secure information as Marketing Information Services (MIS) could be a suitable strategy for orchardists in order to access sustainable development.
The main purpose of this study was to investigate Mechanisms of Reducing Natural Disasters and Risk Management to Sustainable of Citrus Gardens in Mazandaran Province. The Population consists of all citrus farmers in the villages of 12 counties of Mazandaran province, a sample of 290 farmers was selected by using proportional random sampling method among 122361 citrus Orchard men. Data were collected by means of a questionnaire. The Validity of questionnaire was determined through sustainable agriculture experts of Mazandaran County and some faculty members at the University of Tehran, Department of Agricultural Extension and Education, Agricultural Management and Development. The reliability was found to be acceptable. Diagnostic validity by using an average variance extracted (AVE) and reliability by using Cronbach's alpha and composite reliability (CR) were confirmed. To explain the mechanisms Confirmatory Factor Analysis (CFA) was used to modeling the structural equations using LISREL software, version 8.80.
According to the results of the ranking factors related to the mechanism in dimensions, "supportive - credit", "environmental - spatial", "socio-participation", "knowledge-awareness", "infrastructure-institutional "," educational –informational" and "economic factors" respectively were mostly mechanisms and strategies based on factor coefficient. Among the credit-supportive, "insurance" has had the most important role in the structure of credit-supportive factor, thus, according to the regional agricultural insurance and damages in the event that the actual performance of the target area is less than the guaranteed performance is a good solution. One of the major goals of sustainable agricultural systems is decreasing vulnerability and improving sustainable livelihoods in rural people. Therefore adoption of GAP technologies has emphasized to increase elimination of pest with minimum impact on the environment, human health and access to sustainable agricultural development, (achieve to environmental, economic and social sustainability) as well as attention to the sustainability of on-farm activities to certain safety and quality of food and non-food agricultural crops. According to the study, understanding and awareness of farmers to improve skills and farming and horticulture management techniques to reducing natural disasters and risk management and expand the participation of farmers in risk management, to develop processing and packaging industries, convenient and refrigeration practices for storage and preservation of agricultural and horticultural crops, in addition to communication channels network through demonstration farms, farmer field schools, workshops, field days, meeting, SMS, and information and communication channels carried by ICT as necessary solutions recommended. This Provides Information and knowledge share among orchardist and strengthening local associations and with each other. This process helps them to increase their awareness about mechanisms of reducing natural disasters and risk management to sustainable of citrus gardens and find positive attitude toward it. This output complete sustainability goals of agriculture through improving social sustainability. In order to access growers to timely sales service products, the establishment of a new extension system based on an available market with up to date and secure information as Marketing Information Services (MIS) could be a suitable strategy for orchardists in order to access sustainable development.
Zahra Hejazizadeh, Meysam Toulabi Nejad, Zahra Zarei Chaghabalaki, Behzad Amraeei,
Volume 5, Issue 4 (3-2019)
Volume 5, Issue 4 (3-2019)
Abstract
This research was conducted to identify the dust storms in the Midwest of Iran from June 16 to 19, 2015. To investigate the synoptic conditions of the causes of this phenomenon, the ECMWF has an array of 0.125 degrees, including geopotential, omega, and sea level pressure, orbital and meridian components of the wind, specific humidity Soil moisture was applied to a depth of 10 cm. Similarly, for the purpose of routing the source of dust particles, the model of the Minimum Meteorological Parameters (HYSPLIT) Marv was used. The results of this study showed that in Lorestan province, non-ditches created by low-pressure thermal springs and high-altitude movements in Saudi Arabia caused the convergence and sucking of flows to the west of the country, as well as the establishment of a low-pressure cut at the middle levels of the atmosphere in the east of the Caspian. In the event of this risk, it has been effective. According to the average soil moisture from the surface of the earth to a depth of 10 cm in days with dust hazards, the moisture content of dust particles in the dust was less than 15%, due to the flow of streams from these fields without sufficient moisture, fine particles the soil is easily directed towards the study. A survey of Hysplit tracking maps shows that two general paths for the transfer of dust to the studied region can be detected. 1-Northwest - Southwest At an altitude of 1500 meters: passing through the dust nuclei formed in the northwest of Iraq and east of Syria, carry out the transfer of dust to the west-west of Iran. As these currents have been able to transfer dust to the southwest of Iran, this path can be considered the main route of dust dispersion to the region. 2- The western-eastern route at an altitude of 500 to 1000 meters: is the source of particles of this route inside the country (around Hurralazim) that entered the West of Iran and greatly reduced the horizontal visibility, which is the main source of dust on June 18 and 19. The investigation of the path of dust particles in the walnut shows that these particles were initially transferred to lower levels by low-pressure systems in the Midwest of Iran and then pulled in three directions on the ground.
Asadollah Hejazi, , Adnan Naseri,
Volume 8, Issue 2 (9-2021)
Volume 8, Issue 2 (9-2021)
Abstract
Zoning the possibility of landslides downstream of Sanandaj Dam
1-Introduction
The purpose of this study is to select the best model and identify landslide risk areas in the downstream basins of Sanandaj Dam. Every year, mass movements in the region cause damage to roads, power lines, natural resources, farms and residential areas, and increase soil erosion. Kurdistan province, with its mostly mountainous topography, high tectonic activity, diverse geological and climatic conditions, has the most natural conditions for mass movements. According to the available statistics, this province is the third province in terms of landslides after Mazandaran and Golestan. (Naeri, &Karami, 2018). The Gheshlagh River Basin is a mountainous region with a north-south trend. In terms of construction land, it is located on the structural zone of Sanandaj-Sirjan. The study area with an area of 970.7 square kilometers is located downstream of Sanandaj Dam. The city of Sanandaj is being studied within the region. Due to the type of climate and morphological processes, effective parameters are provided for landslides in the geography of the region.
2-Methodology
In this study, 9 effective factors for landslides, including slope, slope direction, fault distance, road distance, waterway distance, lithology, land use and precipitation were used. Using Google Landsat 8 ETM satellite imagery, Google Earth software identified 237 slip points. Then, the coordinates of the slip points were transferred to the Arc GIS software and a map of the landslide distribution area in this environment was prepared. Also, in this study, 89 non-slip points were prepared for use in the training and testing stages of Persephone neural network inside slopes less than 5 degrees. Artificial neural networks are made up of a large number of interconnected processing elements called neurons that act to solve a coordinated problem and transmit information through synapses. Neural networks begin to learn using the pattern of data entered into them. Learning models, which is actually determining their internal parameters, is based on the law of error correction. In this method, by correcting the error regularly, the best weights that create the most correct output for the network are identified. The neurons are in the form of an input layer, an output layer, and an intermediate layer. ahp includes a weighting matrix based on pairwise comparisons between factors and determines the level of participation of each factor in the occurrence of landslides. In this model, a large number of factors can be involved and the weight of each factor can be obtained using expert opinion.
3-Results
According to the results of the high-risk class neural network model, which occupies 31% of the basin area, it is the widest risk zone in the region. The middle class also accounts for more than 29 percent of the area, followed by the low-risk class. The results of the AHP model show that the middle class, with 32% of the area, has the highest dispersion in the region, the low-risk class and then the high-class are in the next position. The AHP model was used to prioritize the parameters affecting the landslide. The parameters of slope, lithology and land use play the most important role in the occurrence of landslides, respectively, and have the least role for slope direction, distance from fault and height. The results of the models used are consistent with the reality of the region's wide-risk hazards, and high-risk areas based on the models used are mostly located in the west and southwest of the basin. These areas correspond to the mountain unit and the steep slope. Based on the results of AHP model, the impact of human factors in the occurrence of landslides is weaker than the natural factors of the region and human factors play a stimulating and aggravating role in primary factors. Five methods for error detection were used to evaluate the models used
4-Discussion and conclusion
.Due to the sensitivity of unstable slopes in the region, any planning to change the use and construction that increases the weight of the load on unstable slopes should be done in terms of geomorphological and geological conditions of the region.
Keywords: hazard zoning, landslide, neural network, AHP. Sanandaj Gheshlagh Watershed
- Mahmoud Roshani, - Mohammad Saligheh, - Bohlol Alijani, - Zahra Begum Hejazizadeh,
Volume 8, Issue 4 (1-2021)
Volume 8, Issue 4 (1-2021)
Abstract
In this study, the synoptic patterns of the warm period of the year that lead to the cessation of rainfall and the creation of short to long dry spells were identified and analyzed. For this purpose, the rainfall data of 8 synoptic stations were used to identify the dry spells of the warm season for 30 years (1986 to 2015). The average daily rainfall of each station was used as the threshold value to distinguish between wet and dry spells. Then, according to the effects of dry spells, they were defined subjectively and objectively with different durations. Thus, 5 numerical periods of 12 to 15, 15 to 30, 30 to 45, 45 to 60 and more than 60 days were identified. By factor analysis of Geopotential height data at 500 hPa, 4 components were identified for each period and a total of 20 components for 5 dry spells. Therefore, 5 common patterns control the stable weather conditions of dry spells. Most dry days are caused by subtropical high-pressure nuclei, which have a wide, even, dual-core, triple-core arrangement. The effect of subtropical high pressure on the dryness of the southern coast of the Caspian Sea is quite evident. Other dry days were caused by southerly currents, weakening of northern currents, and the trough Anticyclones’ area. Also, the anomaly map of the components days at the 500 hPa level showed that the anticyclones and cyclones correspond to the positive and negative phases of the anomalies, respectively.
Sharifeh Zarei, Bohloul Alijani, Zahra Hejazizadeh, Bakhtiar Mohammadi,
Volume 8, Issue 4 (1-2021)
Volume 8, Issue 4 (1-2021)
Abstract
In this research, the most important synoptic patterns of widespread snowfall in the western half of Iran have been investigated. For this purpose, the data of current weather code and snow depth of 36 synoptic stations during the statistical period of 1371-1400, for the months of October to March, were received from the Meteorological Organization of the country. In order to investigate wide snowfalls, the days when more than 70% of the studied area saw snowfall at the same time were extracted as a wide day. In order to perform synoptic-dynamic analysis of wide snowfalls in the western half of Iran, the classification method using cluster analysis was used and maps of representative days were drawn, including atmospheric temperature, moisture flux, geopotential height, tovai, front formation, jet stream, omega index, and orbital and meridian wind data. Trend analysis was also performed using the Mann-Kendall test. The results showed that 4 models justify the widespread snowfall in the studied area in the best way. According to the results in all the models, at sea level, the collision of cold and dry air of northern latitudes with warm and humid air of southern latitudes has caused the formation of frontal fields in the western half of Iran. At the level of 500 hectopascals, the intensification of the meridional currents in the western winds caused the creation of closed centers and as a result the flow changed in the direction of the westerly winds, and the location of the western half of Iran in the east of Naveh Al-Aghti and Sardchal has provided the necessary conditions for air to rise. Also, there was no trend in the number of snow days in the western half of Iran at the significant levels tested. But; The number of snow days has been decreasing over time. In general, it can be concluded that due to the warming of the earth and climate change, the number of snowy days has decreased and these changes have led to a significant shortening of the snow season.
Mrs Masoumeh Alidadi, Professor Bohlol Alijani, Dr Mohammadhossein Nasserzadeh, Professor Zahra Hejazizadeh,
Volume 9, Issue 1 (5-2022)
Volume 9, Issue 1 (5-2022)
Abstract
Comparative analysis of snowfall events in Iran with emphasis on the location of the polar plateau and remote connection patterns
Abstract
Extream snowfall event that may occur at any time during the cold season, has significant social and economic implications. Therefore, the economic and social consequences of these events reveal the importance of identifying the synoptical mechanisms associated with the extream snowfall events. In order to achieve this goal, using daily precipitation and temperature data during the statistical period of 1951-1 2016 and based on multiple criteria, the two three-days extream snowfall events were identified during February 7-9, 1972 and February 2-4, 1988. After selecting samples, a statistical analysis of the teleconnection indices was done and then, using the NCEP-NCAR reanalysis data, the combined patterns of surface and lower, middle and lower troposphere were plotted in the form of three-days mean. Results obtained from analysis of teleconnection indices and their correspondence to the synoptic patterns indicate the weakening of the tropospheric polar vortex and its division into multi-centers in the periods of extream snowfall events. In the event of February 7-9, 1972, though the centers were moved to mid-latitudes, but they are not completely out of the Arctic and to some extent maintain their position in this area. In February 2-4, 1988, the vortex centers have shown a more equatorwards displacement towards the mid-latitudes that the emergence of negative phases of the NAM and AO represent such a situation. However, in both events, the strong and main center of the polar vortex is located in the eastern hemisphere and therefore in a state close to Iran. The weakening of the sub-tropical jetstream in the eastern hemisphere, especially in the Mediterranean, has resulted in the transmission of potential vorticity tabs to mid-latitudes. The equatorwards progress of these tabs has led to the formation of the trough in the western and eastern Mediterranean regions that accompany with a ridge between them, led to the formation of omega bundle patterns and split flow, respectively, in the events of February 1972 and 1988 in this geographical area. The southern boundary of the progress of the troughs has specified by index contour of the edge of the vortex by 552 gpdam, that extends to the southern part of Iran and in the February 1972, event compared with the pattern of the February 1988, had the more-equatorwards progress toward the middle latitudes, and as a result, over Iran.
Keywords: extream snowfall event, teleconnection, polar vortex, the edge of the vortex, blocking patterns.
Ms Vahideh Sayad, Doctor Bohloul Alijani, Doctor Zahra Hejazizadeh,
Volume 11, Issue 2 (8-2024)
Volume 11, Issue 2 (8-2024)
Abstract
Iran is a country with low rainfall and high-intensity rainfall that is affected by various synoptic systems, the most important of these systems is Sudan low pressure, Therefore, recognizing the low pressures of the Sudan region is of particular importance, The purpose of this study is to gather a complete and comprehensive knowledge of the set of studies conducted about this low pressure, structure and formation and its effects on the surrounding climate. The present study was conducted using the library method and a search for authoritative scientific and research sources in connection with research on low pressure in Sudan and no data processing was performed in it. Thus, it has studied and analyzed the temporal and spatial changes of Sudan's low pressure over several years and its effect on the climate of the surrounding areas, especially Iran. In general, the results of this study can be divided into several categories, including studies on the recognition and study of Sudan low pressure, its structure and formation over time, pressure patterns affecting it at different atmospheric levels, and its effects on the climate of surrounding areas, especially Iran. Has been studied, The effect of this low pressure on seasonal and spring rainfall in Iran, snow and hail, floods, thunderstorms and also the effect of remote connection patterns on this low-pressure system have been studied, and finally, the analysis of these findings has been studied. It can be concluded that the Sudanese low-pressure system is a Low-pressure reverse in the region of Northeast Africa and southwest of the Middle East, which is strengthened and displaced in the upper levels of the Mediterranean and Subtropical jet stream and in the lower surface moisture injection from the Arabian Sea and Oman through high pressure. Saudi Arabia is inwardly the cause of severe instability in Iran and a major cause of heavy rainfall in various parts of the country.
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