Iranian Journal of

Background and Objective: Drought and water shortage in recent years caused rice farmers to use maximum groundwater as a secure source. However, the rice is affected not only by the quantity but also by the quality of water. The purpose of this study was to evaluate trend of quality parameters of groundwater in wet and dry periods in 4 plains including Astaneh, Talesh, Lahijan and Foumanat, which are all located in Gilan province.
Materials and Methods: In this investigation, data was collected for quality parameters from 15 groundwater of the 4 plains of Gilan province from 2003 to 2014. The data was collected from 15 piezometer wells of Astaneh, 41 piezometer wells in Talesh, 24 piezometer wells in Lahijan and 44 piezometer wells in Foumanat. For each well, two time series of 15 quality parameters in wet and dry periods were created in SPSS software. The trend was evaluated by Mann- Kendall test that is a nonparametric method.
Results: The results showed that in both periods, the trend of most quality parameters was declined, However, the quality decline in wet period was more severe. In both periods, the pH and Na % were increasing. Additionally, in dry period, the increasing trend of SAR and SO₄ was observed. Overall, the water quality of wells in Talesh plain for cultivation of rice was better than the other plains.
Conclusion: Consumption of groundwater of all the plains in both wet and dry periods for agricultural purposes and especially rice cultivation was without limitation. According to the decreased concentration of the measured parameters during the studied period, it can be expected that groundwater quality of Gilan province plains has been improved.
 

Background and Objective: Groundwater resources are very important for the survival of living beings. Hence, groundwater modeling has a special importance in water management and planning of each region .In this study, numerically simulation of Hamedan–Bahar aquifer flow path was done by GMS software using geological, hydraulic and hydrologic information.
Materials and Methods: First, a 3D hydrogeological model of the aquifer was prepared and then the aquifer flow was simulated by MODFLOW numerical code. The model was calibrated using a trial and error method. Estimation of groundwater flow path was done with MODPATH numeric code. Finally, the capture area was studied and piezometers and direction of groundwater movement in different time were built.
Results: The results of calibration showed that the difference between observed head and computed head was in allowable range (  35 m). Estimation of pollution with MODPATH numeric code indicated that in forward moving, the longest way of pollution transport was 43400 m and in backward moveing, the longest way of flow transport was 8270.65 m. The results of the groundwater flow path indicated that the flow transport direction was from southwest to northeast in line with the hydraulic gradient.
Conclusion: It can be concluded that the current trend of groundwater flow will increase aquifer pollution level, which will damage groundwater aquifer.
 

Background and Objective: Despite the significant improve in air quality in Tehran in 2018 and reducing the average concentration of most pollutants, compared to previous years, air quality is still far from the WHO air quality guideline level and national air quality standards. The purpose of this study was to estimate the effects of air pollution on health in Tehran by considering the spatial distribution of particulate matter 2.5 micrometers or less in diameter (PM_2.5) and population in determining exposure levels.
Materials and Methods: In this study, while introducing the GEMM concentration–response function and BenMAP-CE software, the mortality attributed to PM_2.5 in Tehran and its distribution for 2017 and 2018 was calculated. Hourly PM_2.5 from monitoring stations used to estimate the mean PM_2.5 for 349 Tehran neighborhoods.
Results: The results showed that the average population weighted PM_2.5 concentrations in Tehran in 2017 and 2018 was estimated to be 31.8 and 26.2 µg/m³ respectively. Using the GEMM function, about 7,377 (95% CI: 6,126-8,581) total mortality attributed to PM_2.5 was estimated in adults in 2017 (> 25 years) and the figure for 2018 was estimated as 6,418 (95% CI: 5,918-6,753).
Conclusion: The spatial distribution of deaths attributable to PM_2.5 showed that the total mortality rate per 100000 in the districts 16 and 18 of the Tehran municipality were higher than other districts and the lowest rate observed in the district 1.

Background and Objective: Various aspects including the environmental burdens, social and economic consequences of the waste management(WM) scenarios must be considered to come up with a comprehensive WM plan. Life Cycle Assessment (LCA) approach is a systematic method to quantify the environmental burdens of each WM scenario.
Materials and Methods: This study used an LCA approach to develop a decision support system to analyze different scenarios of WM. Local and global databases were used to develop a comprehensive life cycle inventory database. The model comes with a graphical user interface in Persian to make it easier to use by a wide range of customers. Finally, to evaluate the model, three scenarios were assessed in Karaj city, Iran.
Results: To the best of our knowledge, this model is the first attempt to automate the process of waste management scenarios evaluation in Iran. The model enables users to easily and quickly simulate a wide range of scenarios. All calculations will be carried out by the software in the background and the user only needs to determine his/her scenario of concern which is very easy owing to the user-friend GUI of the software. The model was evaluated by analyzing the current WM in Karaj. The results showed that the waste collection system is the main source of environmental pollution of the WM in Karaj city due to the inefficient system of the waste collection and poor fleet fuel efficiency.
Conclusion: This tool allows users to gather detailed information about the waste management systems. In this way, the user can make informed decisions about the most suitable waste management scenario in a city.