نشریه مطالعات علوم محیط زیست
سال دوم شماره 4 (زمستان 1396)

The purpose of this study is to investigate the dust and predict the best time series models for the cities of Khuzestan province during the years 2019-2023. The statistical method of the library and using the annual data, eight cities selected from Khuzestan province to identify and predict the best time series models using the software Minitab17, spss19 Excel 2013. For this purpose, annual dust data from eight meteorological stations of Khuzestan province during the period of 1990-2010 were collected and analyzed using the ridge test of homogeneity of dust data. Using time series models of dust walnuts and the best model for identifying fitted dust, the accuracy and accuracy of the models were based on absolute error (MAE), absolute error (MAPE), root mean square error (RMSE average), and The BIAS standard has been approved. The results of the most suitable models of Dust Time Series for the cities of Masjed Soleyman and Behbahan are Halt Winters forecast model, Dezful city alone in the model of Arima (1.0.1) and Ahwaz, Ramhormoz, Aghajari, Abadan and Omidieh models Nemo is smoothly achieved. Also, the results of the dust show that the city of Omidieh with the highest difference of dust increases to 79 days and the city of Dezful reaches the lowest number with 9 days. And the rest of the cities are Abadan, Aghajari, Ramhormoz, Ahvaz, Masjed Soleyman and Behbahan, respectively, 75, 45, 45, 41, 36 and 25 days a year.

The concept of sustainability raised the need for more attention to the environmental issue. In the sustainability of the urban environment, the use of land plays a vital and crucial role, as the results of population studies, economics, nature, etc. . For data analysis, quantitative and statistical methods such as per capita green space, green space share from area area, growth rate, population forecast and qualitative methods, and GIS software have been used. Hence, the first and most important step for any planning for the city is the distribution and allocation of uses and the determination of standards and urban capitals based on the city's physical division. The condition of the urban green space of Iran, despite its old age, was not optimal, and the main reason was the lack of proper management of urban green space.

of the main factors in the boom and efficiently produce and biological rural locations now, is achieving the food security. Food security in the rural areas influenced by variety of factors which one of these links, town and villages. In this study, the role of rural-urban links in the the food security of rural households have been investigated. And in terms of the the nature of research is a descriptive research. Statistical population, villages families in the city DEHDASHT in Kohgiluyeh and Boyer-Ahmad is Zylayy Poshteh according to the the 1395 census, the villages has 7 the village has inhabitants of 3450 population, consisting of 690 households. The number of samples required for complete the questionnaire using the Cochran formula 220 families were obtained. In the present research, data collection as a library and a questionnaire to Data analysis by descriptive statistics (mean and standard deviation) and deductive statistics (linear regression analysis) to define the the operational links rural and urban social dimensions, physical and environmental economic and the food security of rural households of 43 indicators and to review method is used average of 50 percent. The research findings showthe average expenditures of rural households in the studied area is equal 747 thousand USD. Research findings show that 64.3 percent of the families surveyed are living in conditions of food insecurity. The analytical results indicate that after the effects of the the general economic 0.230 the greatest impact on the food security of rural households had studied the region.

Carbon dioxide is one of the most important gases that has led to climate change and global warming. About 60 percent of greenhouse gas emissions are due to carbon dioxide emissions. According to the World Bank data in 2014, carbon dioxide emissions, increased from around 9.3 billion metric tons in the 1960s to more than 34.6 billion metric tons in 2011, that is annual growth rate of 2.6 percent and which is about 3.7 times higher. According to the International Energy Agency (IEA) in 2011, Iran has been ranked 9th in the world with the release of 521 million tons of carbon dioxide . Economic and population growth, on the one hand, increase demand for goods and services, which creates more exploitation of resources and environment; on the other hand, more exploitation of resources leads to environmental degradation. All countries for that they can experience economic growth with a healthy environment, need to be aware of the impact of variables on each other and on the environment. Don’t be aware of how the causality relationship between these variables in any country's economy can lead to false and ineffective decisions. Therefore, any planning and policymaking to achieve economic growth and its stability as one of the major economic goals requires investigate of the relationship between economic growth and carbon emissions. However, studying the causality relationship between these variables can play a significant role in achieving sustainable development and taking attention to environmental considerations in decision-making processes.

The subject of air pollution has become important since the emergence of industrial societies. Based on statistics provided by the spokesman of the Ministry of Health and Medical Education on December 8, 2017, in Iran, due to air pollution, 2.48 percent of gross national product is wasted. Also, the amount of damage caused to the national economy caused by air pollution is 34 trillion tomans. Annually, $ 25 billion of the world's economy becomes smoke and goes to the air, due to air pollution. Meanwhile, metropolitan areas have a very significant contribution to this damage. According to the Economic Welfare Theory, any costs that are incurred in society must be paid by the causing factors. Today, in most countries in the world, external costs are estimated and included in the pricing calculations. Therefore, it is important to calculate the external costs of air pollution in codification of an appropriate management approach. For this purpose, the aim of this research is to consider an economic, engineering and management approach to external costs caused by the emission of PM, NOx, SO2, CO pollutants in order to plan and provide targeted solutions for reducing air pollution in Karaj.

How pollutants enter, as well as the speed of releasing pollutants into the atmosphere, affect air pollution. Pollutants may be freed freely, periodically or periodically, either from a source or from several sources or from point and point sources. Also, the dispersion of pollutants depends on how they enter the atmosphere. Lack of information on the distribution of pollutants makes it difficult to determine the impact of their dissemination outside the boundaries of the site and in surrounding residential areas (Shin et al, 2005). Mobarakeh Steel Complex in Iran, due to the production of large amounts Pm10 and Co, the focus of many environmental scientists has attracted. In the presence of amounts of sulfur dioxide gas in the atmosphere, fine particles in the air react with PM10 and become toxic and dangerous substances, which is one of the main causes of urban air quality problems in Mobarakei province of Isfahan. The CALPUFF model is approved by USEPA as an appropriate model for modeling non-uniform and complex currents, including those with complicated earth conditions, as well as in locations where flow and recurrence flow are important. The modeling system consists of three main parts: CALMET, CALPUFF and CALPOST. CALMET is a meteorological meteorological model that calculates meteorological meteorological data from meteorological meteorological models and calculates values for smaller scales using more accurate network layout data using land-use and land-use data. CALPUFF: In fact, a uniform model Lagrangian fluid motion -Gvsy the following procedures for networking time changes, weather conditions in three dimensions, the effects of terrain, wet and dry sessions, interaction plume of smoke and Terrain, broadcast and distribution on the marine environment, Currents are at the bottom of the buildings. CALPOST: Use this section to preprocess output and process simulation files(USEPA(A), 2004). AERMOD is a Gaussian plume model for steady state and for near-site objects based on the structure and implications of planetary boundary layer turbulence. In addition to the AERMOD's primary processor, it is a meteorological pre-processor called AERMET and a ground-based pre-processor, and air pollution is one of the challenges facing the industrial area (USEPA (B), 2004). In this research, the performance estimation of the models has been done in two ways: First, by comparing the observational data of the output models, at the receiver points determined for the models (based on the UTM coordinates), the accuracy of the modeling is obtained at each point in the time periods considered. In the second step, The performance of models is compared with each other.