Mohammad Javad Amiri; Hamid Jourkesh; Ahmad Nohegar
Abstract
Introduction: Flood is caused by a sudden increase in the water level of a river due to heavy rainfall, in which excess water flows out of the basin and the riverbed and enters adjacent areas, causing extensive damage to the region's ecosystems and infrastructure. In order to determine and implement ...
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Introduction: Flood is caused by a sudden increase in the water level of a river due to heavy rainfall, in which excess water flows out of the basin and the riverbed and enters adjacent areas, causing extensive damage to the region's ecosystems and infrastructure. In order to determine and implement a strategic plan in the direction of crisis management, understanding the mechanism and development of the flood phenomenon and the amount of runoff created as a result is a priority.Material and methods: In this study, three events of flood on 16 February 2017, 26 March, 2019 and 23 January 2020, when the average rainfall in the Shiraz watershed was 100 mm every three days, were selected and interacted with a synoptic approach. Atmospheric conditions and flood patterns were identified. Next, using by HEC-HMS hydrological model, the amount of rainfall to runoff conversion in each of the sub-basins in the Shiraz watershed was simulated.Results and discussion: The results showed that the maximum precipitation occurs in February and the minimum in July. The maximum annual rainfall is 627 mm in the mountainous areas of Qalat and Golestan and the minimum is 245 mm in Maharloo lake. Synoptic results showed that the establishment of low altitude and cold-water trough at the level of 500 hPa in the eastern Mediterranean along with the establishment of dynamic low pressure system in Iran caused surface air instability in Fars province and by injecting moisture from the Persian Gulf to the massif. The weather has caused floods in Shiraz. The results of rainfall-runoff modeling showed that the highest runoff in Sadra and Qalat sub-basins were 5773 and 5076 thousand m3, respectively, and the maximum peak discharge in Sadra and Qalat was 666 and 389 m3/sec, respectively. It happened at 17:00. The highest volume of rainfall penetration in Qalat and Chenar Rahdar was 5423 and 2546 thousand cubic meters, respectively, and the lowest level of penetration in the Quran Gate was 247 thousand m3, the main reason being the high density of residential-commercial use in this sub-basin.Conclusion: Therefore, it is suggested that in order to manage the flood crisis in Shiraz, controlling runoff produced in northern sub-basins such as Qalat, Golestan and Sadra and increasing the level of permeability can be effective in controlling floods.
Amir Bahrami; Fatemeh Ahadi; Mehdi Bahrami; Fateme Aghamir
Abstract
Introduction: Today, treated wastewater is widely used on agricultural soils adjacent to urban areas of developing countries to meet water shortages. On the other hand, due to the pollution increase, the limited available resources are threatened. For the production of crops, unconventional water is ...
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Introduction: Today, treated wastewater is widely used on agricultural soils adjacent to urban areas of developing countries to meet water shortages. On the other hand, due to the pollution increase, the limited available resources are threatened. For the production of crops, unconventional water is used in many countries of the world if it has the necessary standard, and municipal wastewater treatment plants are a very reliable source due to their ability to deliver sustainable water in all seasons. In recent years, several studies have been conducted in the field of the effluent quality of municipal wastewater treatment plants and the possibility of using them in various applications, including agriculture, in different regions of Iran. Due to the water crisis that has arisen, especially in arid and semi-arid regions of the country, it is necessary to study and analyze the possibility of further use of this unconventional water resource. However, wastewater recycling can have various health and environmental effects.Materials and methods: In this study, the effluent quality of the Shiraz municipal wastewater treatment plant was investigated using the daily data during 2018 and 2019 for use in various purposes such as irrigation of crops, irrigation of green spaces, drinking of livestock and poultry, fish farming, discharge into streams, artificial recharge of groundwater based on national and international standards. In this regard, at first, the values of various physical and chemical parameters such as acidity, electrical conductivity, total dissolved solids, total suspended solids, total volatile solids, total solids, chemical oxygen demand, biochemical oxygen demand, turbidity, dissolved oxygen, detergents, phosphate, total phosphorus, nitrate, nitrite, ammonia, Kjeldahl total nitrogen, free chlorine, and fat-oil-grease were determined in raw and treated wastewater. Then, while comparing the values of these parameters with the standard of the Environmental Protection Organization of Iran, the removal efficiencies of these parameters were calculated and finally, the quality of the effluent was investigated for use in various sectors.Results and discussion: The results showed that the removal efficiency of BOD5, COD, TSS, NH3, detergents, and fat-oil-grease in this treatment plant is 85, 85, 67, 64, 94, and 68.5%, respectively. The quality of the effluent is only suitable for agricultural purposes based on the standard of the Environmental Organization of Iran, and according to other standards, it is not capable of such use. This effluent can be used to irrigate ornamental fruit trees, fodder crops, plenteous trees and green spaces side of the roads outside the city, field crops, industrial crops, and forestry, as well as drinking livestock and poultry. However, there are limitations for urban green space irrigation, fish farming, discharge to surface waters (such as Maharloo lake in the vicinity of the wastewater plant), and groundwater recharge, although some of these limitations can be improved by upgrading the function of the treatment plant. By irrigating unfruitful plants and forest parks around Shiraz and even part of urban green space, the pressure on water resources can be reduced to a great extent. On the other hand, the continuation of irrigation with this effluent, which contains organic and nutritious substances in a large proportion, has caused an increase in soil nitrate, and it will be possible to leach and transfer it to surface and underground water sources.Conclusion: The amount of quality parameters of the treatment plant effluent is within the standard of Iranian Environmental Protection and can be used as a sustainable water source in areas that are not directly related to humans. In using this sustainable water source for permitted uses, all health issues for the workers of each sector must be observed, and the effluent must be continuously disinfected.
Roshanak Torabi; Shahrokh Pashaei Rad; Mohammad Reza Shokri
Volume 15, Issue 3 , October 2017, , Pages 75-92
Abstract
Introduction:
Ants are the most well-known social insects that have a significant impact on the ecosystems of their habitat. The role of these insects in the physical and chemical changes of the soil and their interaction with plants, microorganisms and other living organisms is undeniable. Iran with ...
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Introduction:
Ants are the most well-known social insects that have a significant impact on the ecosystems of their habitat. The role of these insects in the physical and chemical changes of the soil and their interaction with plants, microorganisms and other living organisms is undeniable. Iran with extensive climate conditions and diverse of habitats, has vast variety of plants and animals specie. Family Formicidae fauna in Iran is far from complete and yet 213 species of 32 genera and 4 subfamilies has been reported.
Materials and methods:
The present investigation deal with the study of ant fauna in Shiraz city. The area was divided into 18 study sites with different ecological factors. Samples were collected equally in times and numbers in the spring, summer and fall season 2014. Collected species were transferred to 70% alcohol and identified with the help of stereomicroscope and available keys. The identified specimens were confirmed by Professor Brian Taylor in Royal Entomological Society of London in England. Ecological condition effects(as altitude, soli sedimentary organic matter (TOM), temperature, air humidity, soil humidity, soil pH and soil grading) on species richness were collected from study sites and analyzed by linear regression test using SPSS22.
Results and discussion:
Among the identified specimens, 19 species belonging to 13 genera of 3 subfamilies were identified which are as below: Subfamily Dolichoderinae: Tapinoma simrothi Krausse, 1911 Subfamily Formicinae: Camponotus (Tanaemyrmex) xerxes Forel, 1904; Camponotus (Myrmosericus) armenaicus Arnol'di, 1967; Camponotus (Tanaemyrmex) aethiops (Latreille, 1798); Camponotus (Tanaemyrmex) sanctus Forel, 1904; Cataglyphis nodus (Brullé, 1833); Cataglyphis frigidus subspecies persicus (Emery, 1906); Lepisiota semenovi (Ruzky, 1905); Lasius turcicus Santschi, 1921; Paratrechina vividula (Nylander, 1846)Subfamily Myrmicinae: Cardiocondyla persiana Seifert, 2003; Crematogaster sp. (sp undet cf Safariyan, 2014); Messor melancholicus Arnol’di, 1977; Messor syriacus Thomé, G., 1969; Messor rufotestaceus (Foerster, 1850); Monomorium kusnezowi Santschi, 1928; Pheidole pallidula (Nylander, 1849); Pheidole teneriffana Forel, 1893; Tetramorium davidi Forel, 1911Conclusion: All the identified species except T.simrothi, C.frigidus, C.persiana, M.rufotestaceus and P.teneriffana were recorded for the first time from Fars Province and the species T.simrothi and P.teneriffana were recorded for the first time from Shiraz City.
Conclusion: Statistical analysis using linear regression in SPSS22 shows a significant difference between pH and species richness of ant communities.
Leila Kokabi; Behnaz Aminzadeh
Volume 6, Issue 2 , January 2009
Abstract
One of the main differences between landscape ecology and other branches of ecology is the application of spatial concepts in ecological planning. Compared to the classical planning approach based on economic land suitability, the principles of landscape ecology are helpful in conserving the ecological ...
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One of the main differences between landscape ecology and other branches of ecology is the application of spatial concepts in ecological planning. Compared to the classical planning approach based on economic land suitability, the principles of landscape ecology are helpful in conserving the ecological processes of landscapes and simultaneously their steady changes. The aim of this study is to propose the application of the principles of landscape ecology in improving the quality of urban rivers, which could help in defining sustainable landscape development. The Khoshk River, located in an arid and semi-arid climate, crosses the city of Shiraz. This river, as the case of this study, has been under pressure due to simplification of its complex natural pattern resulting from the growth of the city. The impact of unplanned development of housing, agriculture and industries have threatened Khoshk River’s natural environment. The research method is based on assessment of human and biophysical units. Zoning in different scales and determining the appropriate indicators based on the theoretical framework of the study and site characteristics help assess the ecological potentials and limitations. The results facilitate policy making and defining strategies for improving the Khoshk River ecological system. The method for analyzing the quality of urban rivers may be generalized in similar situations.
