Original Article
ِAshkan Mohammadi; Naser Shafiei Sabet; Alireza Shakiba
Abstract
Introduction: One of the major implications of accelerated urbanization is the spatial expansion of urban sprawl and the corrosive of villages and peripheral lands that have been numerous in metropolitan areas. The irregular sprawl and extension of the Tehran metropolis into surrounding areas have led ...
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Introduction: One of the major implications of accelerated urbanization is the spatial expansion of urban sprawl and the corrosive of villages and peripheral lands that have been numerous in metropolitan areas. The irregular sprawl and extension of the Tehran metropolis into surrounding areas have led to disturbances and imbalances in the social, economic, and spatial organization of peripheral villages. In recent decades, urban growth analysis has started from a variety of perspectives. Over the past half century this phenomenon has been prominent in Iran. It originally took place in metropolises and large cities, but gradually moved to middle cities due to the centralized policies of the settlement .The study area has been expanding rapidly in the last three decades and has caused many environmental problems and rapid changes in the economic performance of villages and the transformation of valuable natural resources. Therefore, this research intends to investigate the manner and extent of land use changes in the study area by analyzing and accurately analyzing the phenomenon of creep and reducing the adverse effects by providing scientific solutions. Therefore, this research is intended by look up and accurate analysis of the sprawl phenomenon, study the method and extent of land use change in the study area and reduces its adverse effects by providing scientific solutions. Material and methods: For accurate analysis of the effects of sprawl phenomena, descriptive and analytical methods have been used. In this method, after collecting data contains Land sat satellite images with TM, ETM and OLI sensors and after visual interpretation of satellite images due to the absence of stroke errors, cloud spots by using remote sensing techniques and spatial information systems, the land use change process began in 1986, 2002, 2018, and divided into four residential and non-residential construction, vegetation, rangelands and roads. After that, the supervised classification operation was monitored by the SVM algorithm and the detection and determination of the sprawl pattern in the study area. Results and discussion: The calculations indicate that in the region of Tehran -Damavand, due to the crawling growth in discrete form and in some points continuous, the most changes in terms of increase is related to the use of residential construction 9.69% and the use of the road 1%, that this growing trend has reduced the use of pasture and vegetation by about 9.07% and 0.1%, respectively. After field operation and harvesting of samples with two-frequency GPS receivers and introducing it to the software, the classification of complications was performed by support vector machines with a mean total accuracy of 62.69% and a mean Kappa coefficient of 85.33%. Most changes were related to residential and non-residential classes and roads and in the study area, most vegetation coverings and agricultural land became industrial estates and recreational villas. This led to an increase the migration from villages to Tehran's metropolis, followed by the need for urban landscapes and finally fragility and instability of environmental resources. In Tehran- Damavand axis, these changes have been made by various factors and forces during its uneven spatial expansion. Conclusion: In the study of spatial and land use changes, it is important to pay attention to which side effects are slowly changing and which side effects change more quickly. In this research, it was revealed that the study of vegetation compared to other lands had the greatest change. Therefore, if there is no precise planning and policies and continuous monitoring to prevent this trend, there will be harmful and irreparable environmental impacts.
Original Article
Maryam Akbarpoor; Hadi Veisi; Abdolmajid Mahdavi Damghani; Mohammadreza Nazari
Abstract
Introduction: Localization of the food system has become in line with sustainable agriculture for many reasons including ecological advantages, economic benefits, and social considerations. Yet the question is that to what extent food can be locally produced. To answer this question, the concept of ...
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Introduction: Localization of the food system has become in line with sustainable agriculture for many reasons including ecological advantages, economic benefits, and social considerations. Yet the question is that to what extent food can be locally produced. To answer this question, the concept of foodshed can be considered. The concept provides a framework for analyzing local food production at any scale. The foodshed is a land that can supply all or parts of a given population's nutritional needs within a given geographical area. So far, no foodshed study has been conducted in Iran, so this study proposed a model to study foodsheds. By taking a sustainable food system into account, the current research examined the concept of foodshed, the status of food production and consumption in Tehran Province, and the capacity of this province to meet its nutritional needs. Material and methods: The model was used in Tehran Province using a unit named "plant equivalent" to calculate and compare the amount of food produced in the study area and the nutritional requirement of the province’s population. Production of each crop (based on the plant equivalent unit) in each region was calculated by multiplying the crop cultivation land area in the crop yield. The amount of need for each plant equivalent unit in each region was calculated by multiplying the population of that area in the weight of food that is needed of a person in a year. Then, using self-sufficiency formulas, we estimated how much of the population's needs are being supported by the existing production. To calculate self-sufficiency, a concept known as threshold production was used. Calculation of threshold production was done with Matlab using conditional programming and coding. Excel, Matlab, and GIS were used in this research. Results and discussion: One of the most important achievements of the present study was the foodshed assessment of Tehran Province considering its increasing population and providing food security in this province. In the present study, which was carried out on a provincial scale, self-sufficiency in providing the desired food basket for the population of Tehran Province was 22% and the highest and lowest self-sufficiency was estimated in Pishva and Tehran counties, respectively. Self-sufficiency percent in producing crops to provide the desired food basket in Tehran Province was higher in fodder corn (100%) (self-sufficient), vegetables (79%), fruits (56%), barley straw (53%), wheat straw (45%), barley grain (16%), wheat bran (8%), wheat grain (5%), forage crops except corn (4%), rapeseed meal (0/1%), rapeseed (0/06%), respectively. However, in legumes, rice hull, root, pulp, and molasses of sugar beet, corn, and soybean meal self-sufficiency percent was estimated zero percent, meaning non-self-sufficient or total dependence. Conclusion: The results of this study indicated that the percentage of foodshed self-sufficiency in providing the desired food basket for the population of Tehran Province was 22%. Although localization has benefits, it seems that considering the small area and the overcapacity population of Tehran Province and the environmental issues (water scarcity and soil erosion), the boundaries of Tehran Province foodshed should be broadened and the foodshed radius must be increased.
Original Article
َAhmad Soltani Zoghi; Gholam Reza Soltani Mohammadi
Abstract
Introduction: From the perspective of many experts and decision makers, advances in irrigation technology are the main cause of reducing water consumption. Despite these comments, many experts are skeptical of this conclusion. Despite the improvement of irrigation, drainage technologies and improvement ...
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Introduction: From the perspective of many experts and decision makers, advances in irrigation technology are the main cause of reducing water consumption. Despite these comments, many experts are skeptical of this conclusion. Despite the improvement of irrigation, drainage technologies and improvement of resistant species, the expected reduction in water consumption have never occurred. Can the water rebound effect (WRE) phenomenon be responsible for the lack of reduction in water intake? What is the situation in Iran? This study sought to answer these questions. Material and methods: First, it was necessary to determine the impact of technology on the agricultural sector in the provinces using panel data. The data for the years 1370 to 1396 were used for this purpose. In the next step, using information about water consumption and agricultural sector products over the years under consideration along with the estimated model, the factors of agricultural growth rate, water consumption growth rate, and expected and ongoing savings were calculated. The results of these calculations indicated the rate of water rebound effect in the agriculture sector for 31 provinces and made it possible to discuss the effect of WRE on different regions with a simple comparison. To help policy-makers, the five divisions of the Ministry of Interior was used. Results and discussion: The rate of participation in the development of technology was at a high level of significance (0.043). The agricultural WRE amount in Iran was 319.9%. This study confirmed the effect of WRE on agriculture in the country. The effect of water rebound on all regions of the country was also clearly visible and even some industrial provinces such as East Azerbaijan and Khuzestan were more severely affected by this phenomenon. The highest intensity of WRE was observed in the 3rd region of the country, including the provinces of East Azerbaijan, West Azerbaijan, Ardabil, Zanjan, Gilan and Kurdistan, and the lowest was in the 5th area including Razavi, Southern and Northern Khorasan, Kerman, Yazd, and Sistan and Baluchestan. The intensity of the WRE in the southern and eastern regions of the country was lower than in the northern and western regions. The reason for the relatively lower intensity of this phenomenon in the southern and eastern regions was the limited access to water resources, lack of funding to change the irrigation technology, high-quality land, and specialized labor. Although less intensely, it could be clearly seen that more than 80 percent of the saved water across the country was due to the improvement of technology, which was significant in the field of irrigation technologies, by the same agricultural sector. This it indicates the intensity of the WRE phenomenon on the country's agriculture. Conclusion: The trend of increasing water use in agriculture in the country after applying government support policies and the development of irrigation technologies along with the calculated WRE indicated that improving irrigation technologies, due to the increased productivity, initially reduces water consumption, and also, higher profitability can be achieved by reducing water consumption costs. Increased profit is a motive to expand the crop area, which will increase water consumption, in some cases, more than initial consumption. At this very moment, it is necessary that the authorities focus on controlling the water rebound phenomenon, in addition to the concept of reducing water consumption in the agricultural sector.
Original Article
Mohabat Nadaf; Reza Omidipour
Abstract
Introduction:
Biodiversity includes not only the species number and their abundance but also the differences in the functions of any species, which is measured by the functional diversity indices. On the other hand, land-use change and grazing are two important factors affecting biodiversity and ecosystem ...
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Introduction:
Biodiversity includes not only the species number and their abundance but also the differences in the functions of any species, which is measured by the functional diversity indices. On the other hand, land-use change and grazing are two important factors affecting biodiversity and ecosystem services. This study was carried out to investigate the effects of grazing and forestation on functional diversity indices at Cheshmeh Delav in the western part of Northern Khorasan Province, Iran.
Material and methods:
To measure the functional diversity, the single-trait indices (community-weighted mean; CWM) and also the multiple-trait indices (functional richness, functional evenness, functional divergence, functional dispersion, Rao quadratic diversity) were used and measured by the "FD" statistical package in "R.3.3.1" software. The one-way analysis of variance (ANOVA) followed by Duncan’s test was used to compare the mean diversity.
Results and discussion:
The results showed that grazing and forestation have different effects on functional diversity indices. Based on the results, functional richness, Rao index, CWM of height and therophyte had a significant difference in the studied areas. The highest values of functional richness, Rao and CWM of the height index were related to grazing areas. Therefore, the low levels of disturbance factors such as grazing are necessary to reduce competition between plants and an increase in ecosystem function. As CWM of height was the highest at grazing sites, there was a positive relationship between functional richness and CWM. On the other hand, the maximum value of the CWM of therophyte life form was observed in the ungrazing – forestation site due to environmental adverse conditions such as high competition (due to lack of grazing) and disturbance (forestation).
Conclusion:
Using functional diversity indices as an index of biodiversity that considers not only species abundance, but also functional traits was an effective mean in the study of the effects of different factors on biodiversity and the function of different ecosystems.
Original Article
Nader Barani; Ayatollah Karami
Abstract
Introduction: Climate change is exacerbated by natural factors such as aridity and drought or human activities. Identifying and revealing the changes in each factor and what cause them is considered the first step in the study of the process of climatic elements. The trend analysis might be due to natural ...
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Introduction: Climate change is exacerbated by natural factors such as aridity and drought or human activities. Identifying and revealing the changes in each factor and what cause them is considered the first step in the study of the process of climatic elements. The trend analysis might be due to natural changes, such as drought or human activities e.g. increasing greenhouse gas emissions. However the trend in the climatic factors of each area might be normal, its continuity in the coming years may have more significant effects on the economic and social components. Climate change in a region can be detected by investigating the changes in the average rainfall and temperature. This research was carried out in order to identify the time variation of climate parameters (temperature and precipitation) in decuple agroecology regions of Iran. Material and methods: For this study, data on temperature and precipitation variables were extracted annually from all provinces of the country during the period 1985-2015 from the Meteorological Organization of Iran. Since the distribution of a number of climatic parameters such as temperature and precipitation climatic series is not normal, the non-parametric Mann-Kendall method was used for analyzing their distribution. To determine the level of significance in variables and to determine the trend of annual changes, Mann-Kendall test was used with XLSTAT extension software. Results and discussion: The results showed that temperature variable in Central, Northwest, Caspian Coastal Plain, Khuzestan, Central Zagros, Arid Southern, Khorasan, Southern Coastal Plain Arid Central zones had an upward trend and no trend in Southern Zagros zone. Precipitation variable was decreasing in Khuzestan and Khorasan. Precipitation variables in Central, Northwest, Caspian Coastal Plain, Central Zagros, Arid South, Arid Southern, Arid Central and Central Zagros zones were not trendy. The increase in temperature will lead to a significant increase in the annual evapotranspiration rate (which is already higher than annual precipitation in most parts of Iran). The Intergovernmental Panel on Climate Change regards this issue as a serious challenge to arid and low rainfall regions, including Iran, and as a consequence, predicts that the production of strategic products in Iran will decrease compared to the current level of production. The vastness of Iran, along with its geographic location, and the location of heights, prevent the region from fully absorbing the atmospheric humidity. The existence of such conditions causes an inhomogeneity in the amount and pattern of precipitation that has crystallized in the temporal and spatial behavior of the climatic factors. This could be a warning to a country like Iran that is heavily in need of water, and will face water scarcity in the future. Conclusion: The results of the research showed that the mean annual temperature significantly increased in all stations. However, there is no particular trend for the rainfall situation Due to the arid and semi-arid climate of Iran; Iran is one of the countries facing water shortage. Obviously, this shortage will greatly affect agricultural production.
Original Article
Ali Partovinia; Maryam Otadi; Amirhossein Alaedini
Abstract
Introduction: Nowadays, the industrial effluents contain mineral and organic hazardous materials such as phenols, heavy metals, and dyes, which are carcinogenic and poisonous compounds even at low concentrations. An increase in such components especially dyestuffs in the environment makes the remediation ...
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Introduction: Nowadays, the industrial effluents contain mineral and organic hazardous materials such as phenols, heavy metals, and dyes, which are carcinogenic and poisonous compounds even at low concentrations. An increase in such components especially dyestuffs in the environment makes the remediation of these pollutants valuable. Toluidine Red is a pigment containing azo groups, which is invasively used in different industries. There are several chemical, physical, biological, optical, and combinational methods for different pollutant removal from the environment. In recent years, the bioremediation technique has been considerably developed as an effective method in pollutant removal. Therefore, the goal of this study was to optimize the Toluidine Red removal from the synthetic dyes wastewater by Halomonas strain D2 in static culture conditions. In this survey, optimization and variables’ effectiveness study was performed by the response surface methodology (RSM). Material and methods: In this research, the effectiveness status of variables and optimum conditions were studied by the statistical approach of Design Expert V.7 software. Biodegradation of dye was investigated by 30 experiments according to the Central Composite Design (CCD) and RSM. According to previous related research performed by one factor at time (OFAT), the effects of four variables of dye concentration, NaCl salt concentration, pH, and temperature on bioremediation at 10-30 ppm, 2-10 %, 5.5-9.5 and 20-40 °C, respectively, were studied. Bioremediation experiments in the aqueous phase of the synthetic model effluent have been performed in shake flask scale and static culture condition in an incubator for 10 days. Then the analysis of the resulted data was performed by analysis of variance. Results and discussion: According to the results and analysis of variance, salt concentration and temperature are the most significantly effective variables on bioremediation in the studied range while pH and dye concentration were probably less significant. Furthermore, the interactive effect of dye concentration and pH, salt concentration and pH as well as salt concentration and temperature were in a 95% effectiveness possibility limit. On the other hand, the maximum dye removal was observed on the 10th day of the experiment with 62.4%. The optimum condition for bioremediation was observed at a pH of 8.5, the temperature of 35 °C, and salt and dye concentrations of 4% and 16.8 ppm, respectively. By RSM, a correlation of second order for dye removal percentage after 10 days was presented with R2 equal to 0.95. The average error of the proposed correlation and real experimental data was about 9.9%. Conclusion: The second-order correlation proposed in this paper can effectively predict the different operational condition effects on removal of Toluidine Red by Halomonas strain D2 that is a useful bacterium in dye biodegradation. Comparing this survey with our previous study, which was about decolorization by Gb strain, shows that the optimum condition is different for each strain type. On the other hand, D2 strain performance was higher in the basic condition in comparison with strain Gb, however, in acidic conditions, the Gb strain’s performance was better.
Original Article
Amir Ghazilou; Kamalodin Kor; Hamid Ershadifar; Emad Koochaknejad; Mahshid Oladi
Abstract
Introduction: Hypersaline ecosystems provide excellent conditions for ecological studies of aquatic ecosystems. Lipar Lagoon is an understudied hypersaline lagoon located in southeasternmost Iran (northern Gulf of Oman). Knowledge about the biotic and abiotic characteristics of this hypersaline water ...
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Introduction: Hypersaline ecosystems provide excellent conditions for ecological studies of aquatic ecosystems. Lipar Lagoon is an understudied hypersaline lagoon located in southeasternmost Iran (northern Gulf of Oman). Knowledge about the biotic and abiotic characteristics of this hypersaline water system is limited. This research thus investigated the plankton community composition and abundance, and also its variability under variable environmental conditions over one year. Material and methods: Monthly (five replicates each month) water samplings were performed from 2017 to 2018, during pre-monsoon, monsoon, and post-monsoon seasons. Physicochemical properties of water were measured at the site using a portable multi-meter, while other parameters such as silicate, nitrate, and phosphate were analyzed by spectrophotometry. For plankton identification and density measurements, each sample was fixed by adding 3ml of acidic Lugol’s solution, and transferred to the laboratory for further analysis. Results and discussion: The plankton community observed during the study period included Fabrea salina, Dunaliella salina, Pseudo-nitzschia sp., and Spirulina sp. Temporal variations in plankton abundance were evident, mostly in September and November, most of which occurred due to the difference in the abundance of D. salina and F. salina. The impact of environmental parameters including salinity and the concentration of dissolved oxygen, nitrite, silicate, and phosphate on the community structure of planktons was significant. Conclusion: The combination of high salinity, high evaporation rate, low freshwater input, and consequently, low nutrient levels may be the main factors behind the low biodiversity in the lagoon. Being under pronounced anthropogenic pressure due to salt extraction activities, it is evident that further hydrobiological monitoring is crucial for the long-term preservation of the lagoon
Original Articles
Mohammad Reza Asgharipour; Fatemeh Kamari; Mahmoud Ramroudi; Yaser Alizadeh
Abstract
Introduction: Diversification of agriculture is considered an important strategy to overcome the challenges faced by many developing countries due to the opportunities it offers to face heterogeneous production conditions, increase income generation through entry into new markets, and risk management. ...
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Introduction: Diversification of agriculture is considered an important strategy to overcome the challenges faced by many developing countries due to the opportunities it offers to face heterogeneous production conditions, increase income generation through entry into new markets, and risk management. Conservation of biodiversity is one of the sustainable development concepts in agriculture. Excessive attention to the number of products and the extreme use of off-farm inputs, regardless of other ecological functions of these systems, has led to the reduction of biodiversity at all levels. In this context, a comprehensive plan for monitoring crop diversity and identification of factors influencing diversification is necessary. Accordingly, this study was conducted to evaluate the temporal and spatial changes in the biodiversity of agricultural systems in the Ilam province during 2004 and 2016. Material and methods: Data were gathered from statistical yearbooks and reports from the Plan and Budget Organization and Organization of Jihad Agriculture. Stepwise regression analysis was used to identify the factors influencing regional crop diversity fluctuation over time (Also, stepwise recursive regression analysis was used to evaluate the determinant factors in the changes of diversity in agricultural systems.). In order to evaluate the spatial variation of crop diversity in irrigated agroecosystems and its determinants factors, the Shannon-Weiner diversity index was calculated. Based on the assumptions of the study, the influencing factors on the spatial variation of crop diversity were classified into geographical factors, climate and ecological factors, sociocultural factors, economic factors, and management factors. Then, insignificant factors on crop diversity were excluded from the model and finally, the most important determinant on variations between different regions of the province remained in the model. Results and discussion: The findings of this study revealed that over the 12-years period, the general trend in the changes of production systems was a decreasing one; so the agricultural systems’ diversity in all counties, except for Ilam and Dehloran, had decreased, of which the highest value of the Shannon-Weiner diversity index was calculated 1.90 in 2016. The main reason for this increase in diversity was the increase in the number of vegetable crops and reducing the area under cultivation of dominant crops (wheat and barley) during the studied period. Furthermore, the main determinant factors of diversity in the agricultural systems of Ilam Province were the number of villages with inhabitants, average annual net income of a rural household, number of cooperatives, number of dusty days, agricultural land areas, number of production units, age of the beneficiary, minority percentage, amount of urea fertilizer, number of family members, and literacy rate, respectively. Conclusion: Studying the critical points in the agricultural systems of Ilam Province indicated that the top-priority actions to improve sustainability and increase the diversity of these systems are educating farmers, helping them reach economic stability and improving production management and water resources management.
Original Article
Mahmoud Ahmadi; Zahra Alibakhshi; Manouchehr Farajzade Asl
Abstract
Introduction: Change detection is a process to find the paradoxical regions in different temporal imageries of a similar area. Vegetation is very effective at the absorption of grime and lead, prevention of the spread of contaminations in urban environments, clearing the air, and reduction of heat islands. ...
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Introduction: Change detection is a process to find the paradoxical regions in different temporal imageries of a similar area. Vegetation is very effective at the absorption of grime and lead, prevention of the spread of contaminations in urban environments, clearing the air, and reduction of heat islands. The need to investigate the decrease or increase in vegetation is extremely important in Tehran as a metropolis, as well as its satellite counties because of the increase in population and construction. The purpose of this research was to investigate the spatiotemporal changes in the vegetation of Tehran and its satellite cities in association with temperature during different temporal periods. The results of this research can be useful in studies concerning urban viability, reducing the effects of urban heat islands, and environmental sciences. Material and methods: Initially, the extraction and preparation of data were carried out using the ETM+ sensor of Landsat 7 satellite from 2001 to 2015, with June being selected as the hottest month of the study area. Then, the selection of days to be studied and correcting imagery, preparing LULC maps and plotting the area percentage was done. The computation of vegetation indices and built-up areas and the calculation of land surface temperature along with the assessment of the accuracy of surface temperature data were other stages of the research methodology. Finally, the area percentage of each index, as well as the scatter plot and Gaussian function chart were produced and the spatial variation of vegetation was studied. Results and discussion: According to the land use and land cover map (LULC) in 2001, 2005, 2010, and 2015, the vegetation significantly increased in 2015 compared to previous courses. The development of the residential area in the west region was higher than in other regions. In the charts of the area percentage for each land use class and its change over the four selected years, the vegetation percentage has been decreased since 2001, which continued in 2010 and 2015. In this study, the relationships between surface temperature and NDVI and SAVI indices were not linear, which showed that there is another controlling factor. In the normal density function chart, which is usually described by mean and standard deviation, variations of NDVI and SAVI indices were similar in the second and third periods, and the mean increased in these two periods compared to the first period, and the height of curve increased due to the reduction of variance. In this study, the results showed a decrease in the value of LST in the second and third periods from 2006 to 2015. On the other hand, the vegetation area was increasing in the region. From a spatial point of view, Tehran has the highest percentage of class one of NDVI that have no vegetation surfaces. Conclusion: Regarding the study of NDVI, SAVI and NDBI indices, the overall trend of vegetation cover in the study area was increasing. Considering the values of 15R2"> , the vegetation in Ray County was defunct. In the cities of Robat Karim and Tehran, vegetation cover was increasing. The high growth of satellite towns in the surroundings of Tehran has led to the allocation of land and fields and vegetation to residential areas, which exacerbate the heat islands and the unfavorable conditions of life.
Original Articles
Ravanbakhsh Shirdam; Amir Shirka; Sina Hassanoghli; Nematollah Bakhshi
Abstract
Introduction: The construction of green concrete is of utmost importance, due to its high compatibility with the environment, and also because of the reduction in the environmental side-effects related to the manufacture of materials used in concrete construction. Material and methods: The current investigation ...
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Introduction: The construction of green concrete is of utmost importance, due to its high compatibility with the environment, and also because of the reduction in the environmental side-effects related to the manufacture of materials used in concrete construction. Material and methods: The current investigation made use of red mud and ground granulated blast furnace slag (GGBFS) as (supplementary material) to cement, in order to observe their effects on the compressive strength of ordinary and early high strength concretes within various water to binder ratios (w/b). The required tests were designed using DX7 software, meaning to optimize the three variables of red mud percentage, slag percentage, and w/b ratio. Eighteen mixes were produced within 7, 28, and 56 days, according to the test design. Results and discussion: The produced concrete specimens demonstrated an optimized red mud and slag amount of (15%, 10%) and (7.5%, 20%), with the w/b equaling 0.3 and 0.375, respectively, keeping pace with the standards of both normal and early high strength concretes, in terms of strength. Conclusion: The optimized mixes obtained in the current study were able to achieve a strength of 90 MPa. The above indicates the suitability of red mud and GGBFS as an alternative to cement.
Original Article
Marzieh Niliyeh Brojeni; Mozhgan Ahmadi Nadoushan
Abstract
Introduction: During the past decades, population growth, rapid industrialization, increased air pollution at low levels of the atmosphere, and the impact of heat island have caused dramatic changes in the local climate of the big cities. The release of heat energy increased greenhouse gas emissions, ...
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Introduction: During the past decades, population growth, rapid industrialization, increased air pollution at low levels of the atmosphere, and the impact of heat island have caused dramatic changes in the local climate of the big cities. The release of heat energy increased greenhouse gas emissions, and land use change are among the main causes of local climate change in cities. The effects of urban environments on the atmosphere appear more often as thermal islands. Green space would be effective in reducing the temperature and increasing the humidity, and finally reducing the thermal island phenomenon as well as reducing runoff, improving the comfort of the citizens and, ultimately, the sustainability of the urban environment. The objectives of this study were to prepare land use maps and NDVI vegetation index, as well as land surface temperature maps, and to study the distribution of thermal patterns of land surface and temporal and spatial variations of vegetation and their relation in Isfahan from 1985 to 2016. Material and methods: For this purpose, satellite imagery was downloaded from the US Geological Survey site. Using the three Landsat satellite TM images of August 1985, 2010, and 2016, the NDVI index was quantitated using Terrset software, and their maps were prepared. Then, by generating land use maps using the maximum likelihood supervised classification method, the analysis of the changes in land uses (such as city, road, agricultural fields, barren lands, river, mountains, and green spaces) was done. Finally, Land Surface Temperature (LST) index was used to estimate the land surface temperature (LST) and its relationship with the vegetation maps. Result and discussion: The trend of land use/cover changes in the study area showed that during the study period, severe degradation occurred in the green space of the area and the main part of these changes was the conversion of green spaces to urban areas. Also, the results indicated an inverse relationship between LST and NDVI index. The results showed that the growth of urban heat islands was toward areas that had encountered poor vegetation and developed constructional uses (residential, industrial, etc.). The results also indicate an accelerated increase in temperature in recent years compared to previous years, as the average annual temperature increase in the period from 2010 to 2016 was 0.61 °C, while the average temperature increase of 0.05 °C was observed from1985 to 2010. Conclusion: The analysis of the changes in thermal islands of Isfahan was indicative of the increase of thermal islands and spatial reduction in urban cool areas. It can be concluded that the changes occurred in this 30-year period (1985-2016) in various aspects, such as population increase, urban area increase, and land use change eventually increased the area of hot spots. Because of the correlation between surface temperature and NDVI vegetation index, the necessity of protecting vegetation and green space, especially in urban areas, is a critical variable for climate change modification for responsible institutions in urban management. The results of this study could provide critical insights on precise and effective urban vegetation management with the purpose of Urban Heat Island mitigation for urban planners and managers.
Original Article
Fatema Rahimi; Abolghasem Sadeghi Niaraki; Mostafa Ghodousi
Abstract
Introduction: Noise pollution is one of the most important and growing pollutions in large cities. Measuring sound pollution is an essential step to control and manage its effects. Therefore in this research, zoning and modeling of noise pollution was carried out in one of the densely populated areas ...
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Introduction: Noise pollution is one of the most important and growing pollutions in large cities. Measuring sound pollution is an essential step to control and manage its effects. Therefore in this research, zoning and modeling of noise pollution was carried out in one of the densely populated areas of Tehran, region 16. In this study, at first eight stations were selected to study area. Material and methods: At the next stage, 46 stations were selected in the studied area and the equivalent level of sound was measured for each station in three periods: in the morning, at noon and at night; and results were used to determine the level of sound pollution. In addition, one of pathways of transit network of area 16, i.e. Shahid Rajaei Highway was selected and noise intensity was measured at different intervals for zoning and modeling of noise pollution of that highway. Then, a model was proposed to predict the level of noise intensity at different distances from the highway. To verify the accuracy of the proposed model, another highway was investigated and a comparison test was performed between measured and predicted values. Results and discussion: The percentage error between predicted and measured values is very negligible and thus the proposed model can be used to evaluate the pollution of other highways. The results obtained from the main stage of this study revealed that the maximum average equivalent level of sound in highway is 83.5714 Db and highway side until 30 m is not suitable for residential use. The minimum average sound level allowed for residential areas is 58 db. Conclusion: Other results of this study indicate that in all sound measurement stations in transit network, the mean measured equivalent level of sound is more than accepted standard in Iran. Due to high noise pollution in the area under study, the proposed solutions to control noise pollution are to use sound walls on highways and to create more green spaces in areas prone to pollution.
Original Article
Nahid Mohammad Hosseini; Maryam Robati; Majid Amidpour
Abstract
Introduction: Utilizing renewable energies is one of the most effective ways to deal with environmental pollution resulting from fossil fuel power plants. Renewable energy sources are considered as clean energy sources, but some of these power plants may change the ecosystem of the region and disturb ...
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Introduction: Utilizing renewable energies is one of the most effective ways to deal with environmental pollution resulting from fossil fuel power plants. Renewable energy sources are considered as clean energy sources, but some of these power plants may change the ecosystem of the region and disturb the ecological balance. The purpose of this research was to evaluate the environmental impacts of renewable energy (solar-wind) in Salafchegan- Zwaryan Special Economic Zone using the Iranian matrix and rapid impact assessment matrix (RIAM). Material and methods: In this research, basic information of the area was collected and factors affecting the development of solar and wind power plants were studied based on the internet search and field observation. According to these studies, the potential environmental impacts of the implementation of renewable power projects on the physical, biological and social, economic and cultural environments were determined. These impacts were separately predicted in construction and operation phases using the Iranian matrix method and the Rapid Impact Assessment Matrix (RIAM). The Iranian matrix and RIAM, considering the effects of project implementation in both the construction and operation phases on the environmental components, are applied methods for environmental impact assessment in Iran. Results and discussion: The results from the Iranian Leopold and RIAM indicated that in the renewable power plant construction and operation phases, the most important positive consequence in the physical environment was related to surface water quantity and the economic, social and cultural environment associated with employment and salary. The most important negative consequences in the physical environment were related to the weather and sound quality in the biological environment related to wildlife coverage and in the social- economical-cultural environment related to perspectives and antiquities. Also, the most negative impact was related to waste and effluents, wastes disposal, risks, and hazards. Also, the most positive impact was energy supply and consumption, green space, land earning, and human resources. It should be noted that the construction phase of such projects was short and would be considered as a long-term investment for future uses. Conclusion: According to the results of both matrices, the construction of solar and wind power plants, regarding the least negative consequences on the various components of the environment, was chosen as the most favorable management option, and without providing a solution, the project performance was confirmed.
Original Article
Pouya Aghelpoor; Vahid Varshavian; Mehraneh Khodamoradpoor
Abstract
Introduction: Evapotranspiration is a key principle of water balance and an important element of energy balance. Therefore, forecasting and estimation of evapotranspiration in agricultural water management, forecasting and monitoring drought, and the development and exploitation of effective water resources ...
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Introduction: Evapotranspiration is a key principle of water balance and an important element of energy balance. Therefore, forecasting and estimation of evapotranspiration in agricultural water management, forecasting and monitoring drought, and the development and exploitation of effective water resources might be valuable and practical. The purpose of this study was to model the Reference Evapotranspiration time series (ET0) at Rasht Synoptic Station with two SARIMA and GRNN models during 1956-2017 and its forecast for 2018-2027. Material and methods: Rasht is located in the temperate and humid parts of northern Iran and in the southern strip of the Caspian Sea. In this study, the Adjusted ThornthWaite method (ATW) was used to estimate ET0, the credibility of which was previously confirmed by researchers for estimation of reference evapotranspiration rate in Rasht. Evapotranspiration values were estimated for the time period of 1956-2017. Two models were selected for modeling and validation of the ET0 series. The SARIMA model is based on seasonal stochastic models, and the GRNN model is based on artificial intelligence. The models’ inputs were selected on the basis of three previous monthly and yearly. The target-input matrices were divided into calibration (75%) and validation (25%) sections. Autocorrelation Function (ACF) indicated a seasonal trend in the ET0 monthly series, with a return period of 12. Four times seasonal differentiation, revealed that the best degree of SARIMA’s seasonal integrated degree was the first-order. Other SARIMA operators, including seasonal and non-seasonal autoregressive, and average seasonal and non-seasonal moving, were selected by trial and error. Optimization of the GRNN model was accomplished by trying and error of the spread parameter. In this study, criteria such as RMSE, NS, and R were used to check the error and correlate the outputs of the model. Results and discussion: The best model of SARIMA pattern was SARIMA (0, 0, 1) (0, 1, 1)12 which has RMSE and NS values of 8.89 mm and 0.97, respectively. The GRNN model had its best performance by applying the total inputs. The RMSE and NS values were 9.22 and 0.96, respectively, for GRNN’s best output. The difference between the two models was reported in predicting the year’s minima (January-February), which showed SARIMA’s better performance. To compare these two models, the Taylor diagram was also used, which showed that the accuracy of SARIMA not only in error but also in the correlation and estimation of the true deviation of the real values was slightly more accurate than GRNN. After evaluating the models and assessing their acceptable performances, best extracted models from both SARIMA & GRNN were used for ET0’s long-term forecasting up to the next ten years (for the period of 2018-2027). Conclusion: The results of the forecasts for Rasht’s future showed a sharp ascending trend in the rate of evapotranspiration in the years 2018-2027 (compared to the period of 1956-2017). This is a warning of a rapid increase in the evapotranspiration rate in the years ahead, in the wet area of Rasht. This issue is very important for the surface water and groundwater resources planning, agricultural uses, and will be a serious warning to farmers and water managers in this area.
Original Article
Zeinab Feizolahi; Mohammadreza Shahbazbegian; Seyed Abdolkarim Hashemi; Siavash Shayan
Abstract
Introduction: Lack of fresh water resources to meet water demand has been being looked on as a main challenge of dryland countries in the world. Iran is also suffering from the issue in particular at its sothern regions connecting to the sea. One of the main option on the table to tackle the problem ...
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Introduction: Lack of fresh water resources to meet water demand has been being looked on as a main challenge of dryland countries in the world. Iran is also suffering from the issue in particular at its sothern regions connecting to the sea. One of the main option on the table to tackle the problem is water demand management has been bolded in Iran as water-related spatial planning scheme. As a result, in term of the water supply, the Minab plain is one of the most important region of the Hormozgan province in Iran and various economic sectors of the plain have been facing with many problems due to the lack of access to water resources. It is manifested by partial or no satisfaction of expressed demand, economic competition for water quantity or quality, disputes between users, irreversible depletion of groundwater, and negative impacts on the environment. In this regard, one of the most important policy option picked up to reduce these problems is the water-related spatial planning. Such approach focuses on spatial relationships and has been considered as an effective way to integrate economic, social and environmental programs into spatial development (Davies and Simonovic, 2011); In that piece, each region spatial organization crystallizes the flow and pattern of communication between different sectors in the region. But the traditional spatial planning approach, in terms of analysis, has been confining to tools such as GIS suffering from being mostly static and nonlinear. Material and methods: The main idea of the paper is that in water-related spatial planning studies, in addition to the traditional view, it is necessary to pay more attention to the system thinking so that the pattern of communication between different economic, social and environmental sectors could be related to water resources in dynamically and nonlinearly manner over time (Davies and Simonovic, 2011). Thus, in the present study, the given mechanism governing the important parts interacting with the water resources of the Minab plain as the spatial organization has been mapped through system dynamics principles, drawing a system mechanism. System dynamics is efficient knowledge to map and analysis following interactions among spatial organization attributes (Sterman, 2000). Results and discussion: Causal Loop Diagrams (CLDs) consisting of two kinds of Reinforcing and Balancing loops are being considered as the base of realizing structure of a system. In fact, the paper initiates to consider the spatial organization as a system to draw efficient policy options and discover complex interactions through it. That’s referred to the main principle of SD implying on structure of a system as a main reason responsible for its behavior. As result if we are going to analysis a spatial organization, considering it as a system, we need first to realize just its structure. To discover the structure, CLDs tool has been being introduced in SD (Richmond, 1993). Conclusion: Finally, apart from conventional policies around water supply, two policies based on water demand management approach have been extracted and discussed based on the performance of the given mechanism to maintain the spatial organization equilibrium of the Minab plain.
