kazem rangzan; Alireza Zarasvandi; mostafa kabolizadeh; shahin mohammadi; jasem mayahi
Abstract
Introduction: Particulate matters are one of the main air pollutants in urban areas, which are usually produced from various sources such as urban vehicles, fossil fuels, industrial activities. They may cause respiratory diseases, cardiovascular disease and death. It is, therefore, very important to ...
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Introduction: Particulate matters are one of the main air pollutants in urban areas, which are usually produced from various sources such as urban vehicles, fossil fuels, industrial activities. They may cause respiratory diseases, cardiovascular disease and death. It is, therefore, very important to be aware of spatial changes in these pollutants in areas with high levels of pollution. In this regard, the present study was conducted with the aim of spatio-temporal evaluation of the PM2.5 index in the period 1998 to 2016 in Khuzestan ProvinceMaterial and methods: For this study, first, precipitation, land surface temperature (LST), wind speed, Digital Elevation Model (DEM) and vegetation cover parameters were prepared using four satellites i.e. Terra, Landsat 8, SRTM and GPM, and ground data. Then PM2.5 index for four periods of 1998, 2004, 2010 and 2016 was extracted using satellite products for Khuzestan Province. Also, information on the distribution of the population and industries of the province was received from the relevant organizations. Finally, after providing the spatio-temporal changes of PM2.5 index in Khuzestan Province, the spatial changes of this index were studied with the mentioned parameters to evaluate the effect of each of these parameters on the contamination degree of this index.Results and discussion: The results of the present study showed that the southern cities of the province such as Mahshahr, Abadan and Shadegan are regions with higher potential in terms of particles smaller than 2.5 microns in size. The results of the study of population density and industries of this province showed that most of the cities in which the air pollution rate was high due to the PM2.5 index, had more industries and population density. The results also showed that in all study periods, in the northern and northeastern parts of the province, the amount of air pollution caused by this index was much lower than other regions of the province and the reason for this could be the low density of industries and population of these cities, among which we can mention the cities of Lali and Indika. In addition to the direct relationship between industry and human activities in increasing and decreasing the concentration of PM2.5 index, the relationship between this index and several factors (DEM, wind speed, precipitation, temperature and vegetation cover) was investigated. The correlation results between the mentioned parameters and PM2.5 concentration showed that the highest correlation was between PM2.5 concentration and precipitation and this relationship was inverse.Conclusion: It can be concluded that the concentration of PM2.5 pollutants in the southern and central areas is much higher than other areas and this could be due to the high density of power plants, industries and vehicle pollution in these areas. In addition, environmental and climatic factors can play an important role in the persistence and spread of the air pollution layer of this index. It should be noted that this research can be used as the basis for decision-making for air pollution management, which is an important step towards overcoming the crisis of air pollution.
Ali Asghar Firouzjaeian Galougah; ُSepideh Nasiri
Abstract
Introduction: Social order has high importance in every society. Disturbance in a social order will have a lot of costs for society. Littering is an example of citizens’ social disorder in the field of environmental citizenship that is transformed as a social problem in our society. The purpose ...
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Introduction: Social order has high importance in every society. Disturbance in a social order will have a lot of costs for society. Littering is an example of citizens’ social disorder in the field of environmental citizenship that is transformed as a social problem in our society. The purpose of this research was the pathological analysis of student’s social order with emphasizing on littering. Littering became a serious problem in all environments in our society. This problem in a university, as an educational and cultural environment, is indecent and needs to be assessed. Material and methods: The study was conducted by a survey. The statistical population was all the students of Mazandaran University in the 95-96 educational semester. The sample size was 384 individuals and was collected by categorized sampling. Data were collected by questionnaire and analyzed by SPSS Amos software. Littering was the dependent variable, consisting of throwing paper, gum, and plastic. Independent variables were taken from the theory of social learning. Results and discussion: In this research, the theory of social learning was used as a theoretical framework to assess various reasons for littering in different environments. In this theory, every behavior is a result of learning in different environments. Of all respondents, 55.8 percent were women and 44.2 percent were men with an average age of 24. Littering among students was classified as medium. The results of the Pearson correlation showed that there was a significant relationship between littering as an indicator of social disorder with the observation of others’ littering, weak formal and informal control, imitation, and positive definition of littering. Also, path analysis showed that these variables can explain 28% of the variations in the dependent variable (littering). In multiple variable analysis, the positive definition of littering had a direct and positive effect on littering. The other variables had indirect effect on littering. Conclusion: Essentially, littering is an important problem that we encounter in many environments. Nowadays, litter accumulates in rivers and city environments such as universities. The academic culture of universities requires academic persons in different fields to obey the social order. Therefore, the process of learning social order seems necessary.
Marziyeh Aghasi; Naser Mehrdadi
Volume 16, Issue 3 , October 2018, , Pages 167-180
Abstract
Introduction:
Fish processing industry produces huge amounts of solid waste and wastewater. This wastewater consists of preliminary processing of the raw fish, washing the plant, and raw offal products (e.g., blood and viscera). The high-fat content of industrial wastewater causes problems in treatment ...
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Introduction:
Fish processing industry produces huge amounts of solid waste and wastewater. This wastewater consists of preliminary processing of the raw fish, washing the plant, and raw offal products (e.g., blood and viscera). The high-fat content of industrial wastewater causes problems in treatment and disposal and raises environmental crises. The purpose of this study is to select the best method for organizing a wastewater treatment in fish processing plant based on the most widely used wastewater management technologies worldwide.
Material and methods:
This research was done by the AHP method. Based on the general conditions in fish wastewater treatment plants in industrial estates and expert judgments, and by using technical, economic, environmental, and administrative criteria, the processes were carried out. Treatment of wastewater included trickling filter, aeration lagoon, anaerobic digestion, and active sludge. The obtained results were assessed by the Expert Choice software.
Results and discussion:
According to our results, the best method was the active sludge method with a score of 0.417 and after that, aeration lagoon, anaerobic digestion and trickling filter with a score of 0.284, 0.264 and 0.052, respectively, were the best choices based on the expert's opinion.
Conclusion:
According to the technical, managerial, environmental and economic criteria and sub-criteria, this study showed that the best method for wastewater treatment in a fish processing plant was the active sludge.