JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
Year:2005 | Volume:- | Issue:24|Papers Count:10

Nowadays the majority of people spend 80% to 90% of their time indoors and hence different air pollutants target them. This study aims at establishing a correlation between the air pollution concentrations of outdoors and indoors air quality. The main indoor air pollutants, namely CO and PM10 have been identified as real problems of Tehrans indoor air quality. Topographically, Tehran is a bowl-shaped city with lacks rain, contains weather inversion during 70% of the year, uses older models and used vehicle in the streets, and has no wind for half the year. This research covers different types of locations, for measuring indoor and outdoor air quality such as, residential(R) and office (O) environments. For field studies, 5 stations were selected within a 500-meter radius. The locations selected are: Nejatollahi(O), Pardison(O), Fatemi(O), Gholhak(R) and with different terrains. Simultaneous measurements of air pollution concentrations were made between 8:00 to 16:00 in both indoor and outdoor conditions. The study shows that there are direct significant correlations between indoor air quality and nearby outdoor air conditions. The ratio of indoor air pollutants concentration to outdoor air pollutants concentration is defined as p. GRIMM and CO measuring instruments were used for sampling and particle deliberateness. The measurement results for different locations indicate: 1.Stations and areas totally affected by open space show extreme influence of indoor air quality from nearby outdoor by signifying ρ= 80% for PM10 and 45% for CO. Variation of ρ shows, ρ CO has more tendencies to a straight line than ρ PM10; in fact, ρ CO is between 37% to 68% and, under similar circumstances, ρ PM10 is 69% to 92%. 2.Air condition is very important in buildings to push particles and CO out and prevent pollution from coming in. 3.Finally, the results of the total measurements of the five stations are as follows: About 70% of locations heavily depend on CO, 10% depend a little on CO, and 18% show no dependency on CO. 27% of the tested areas were highly affected by PM10, 36% with low dependency and 27% with no dependency on PM10 ..

Chitgar artificial lake, located in urban District 22 of Tehran Municipality, northwest of Tehran, has a volume of 10 million m3, an average depth of 10m and an area of 224 hectares and is Irans largest man-made lake. The most important water resources of the district, which can support the lake, are the Kan River, the districts runoff, the middle part watersheds runoff, and the treated wastewater of the urban region. In this study, the way to take water from each resource individually or together are discussed, and twelve different choices of resources to maintain the lake water are considered. In this research, WQRRS model has been run to each of the 12 aforementioned choices individually to predict phosphorus concentration as a nutrient in the lake for each one. This simulation has been done during a five-year period, which is assumed to be a typical period of time. In this way, it would be possible to predict the throphic level of the needed input data to run the model: quality factors, meteorological data, and geometrical characteristics of the reservoir, the characteristics of inflow and also the needed coefficients for the model. These data have been collected from hydrometric and meteorological stations of the region and also from the results of other studies. After running the model, the simulation results show that choices 2 and 4 are the best resources to support the lake water and have the fewest difficulties in regard the eutrification problem. The results also show that DO concentration in Kan River is at an acceptable level.

Chromium is present in different types of industrial effluents, causing environmental pollution . In this paper, it is aimed to quantify the chromium sorption ability of native fungi ( Mucor sp , Aspergillus sp., Alternaria sp and Fusarium sp ) isolated from industrial waste water at the optimum absorption conditions . Higher absorption percentage is noted at lower initial concentration of Cr ions while the absorption capacity of the biomass increases with higher concentration . Uptake was determined by spectrometry at the wavelenght of 540nm . This investigation showed that biosorprion of Cr(VI) ions using native fungi induces the industrial effluent to be corresponding with environmental laws and standards . Results from this study showed that bioabsorption capacities of Mucor , Aspergillus sp(B), Aspergillus sp(G) and Alternaria were 60 .2 , 38.2, 35.1 and 34.7 mgCr6+/g dry biomass, respectively . Fungal biomass showed significat sorption Cr: Mucor (99.9% for 150 mg /l Cr6+ , %50+ 1 for 250 mg/l Cr6+ ), Aspergillus sp(B) (%99 for 150 mg/l Cr6+), Aspergillus sp (G) 99.8 for 100 mg/l Cr6+ , Alternaria %50 + 2 for 100 mg/l Cr6+ ) .

After gathering a few samples of wastewater from Isfahan industrial units, the amount of their pollution has been measured by specifying the amount of heavy metals, BOD, COD and TOC. Besides, heavy metal resistant microorganism were isolated and also the percentage of their resistance was calculated. The relationship between physicochemical factors of these samples including BOD, COD, pH and the existing metals with resistant bacteria is discussed and examined. According to the obtained results, EC and pH are not related with the percentage and presence of resistant microorganisms. Between the concentration of Pb and Cd with the rate of BOD, a positive relationship was observed. The percentage of microorganisms resistant to zn and Cd showed a positive relationship with the concentration of these metals in wastewater and with the rate of BOD and COD, so that with an increase in the concentration of these metals, BOD, COD and the percentage of the resistant microorganisms increas, as well.

This study was carried out in 2004 with the purpose of determining the source and quantity of pollution in the livers of fishes of Khorramabad watershed by some pollutant elements. Fourteen environmental elements were distinguished in the liver of various species of fishes that have been sampled by electrofishing method from 15 sites within this watershed by using atomic absorption spectrometer and flame photometer. The most important sampling sites were local mines, agricultural lands, mixed zones and urban/rural residential areas. The elements of lithium and silver were seen in none of the analyzed fish samples. The minimum concentration of trace elements in fish liver of the watershed belongs to vanadium and the maximum concentration belongs to iron. High concentration of zinc in liver samples is because of the fishes need to this minor nutritional element especially in early days of growth. Poor concentration of mercury and arsenic in fish liver tissue is the result of agricultural poisons and drainage waters of marginal farms entering the surface waters of the study unit. The trace elements concentration in fish liver is positively related with the concentration of these elements in the food, water and sediments consumed by the fish, and with the rate of bioaccumulation.

Density and succession of benthic invertebrate of four Artificial Reefs (cemented rope, brick, wood, ceramic) were studied. The samples were collected every fifteen days form March till September 2004. Sampling was done in the sedimentation pool in Ecological Research Center of Caspian Sea, Sari, Iran. A total of 2,901 benthic individuals per m2 of six species were collected that include two species of bivalves, three species of gastropods and one species of crustacean. The biomass of benthos was measured as wet weight. The Total benthos biomass was 975.636 gr/m2. Also the temperature was measured and its relationship with the density and biomass of invertebrate was analyzed.Considering the succession of benthos, first the two algal species of Chara sp. and Nitella sp. appeared on Artificial Reefs; then, the gastropod Psuedomnicola sphaerion and finally, bivalves Dreissena polymorpha and Cerastoderma lamarckii. The gastropod Valvata piscinalis appeared later. After that, the gastropod Planorbis contortus and finally the shrimp Palaemon elegans were found on artificial reefs. D. polymorpha showed the densest population on reefs with a density of 593.108 gr/m2. Results also showed that brick and ceramic treatments attracted more benthic animals (P<0.01). Cemented rope was next and wood was the last in number and biomass of the benthos (P<0.01). The Presence of fish (Carassius carassius) and frog (Rana rana) species around the artificial reefs showed that artificial reefs produce food for the bigger predators.

This Study was carried out to investigate the effects of ground water overuse in Anar region, 200 km northwest of Kerman Quality loss of ground water, destruction of vegetation and soil, desert advancement, and destruction of environment all have necessitated this study. Samples were taken from 50 wells using a one-stage cluster method. The investigated parameters in water samples included Na, Cl, CO3, HCO3, SO4, Ca, Mg, K, Electrical conductivity, and Na absorption ratio. The results show that the amount of most parameters were beyond normal limits; for example, mean level of Cl and mean Ec were 4118 mg/lit 13961 micro mus /cm, respectively. In the following step, and based on the obtained results, the area was divided into 3 regions and the water of each area was analyzed for irrigation and drinking. The results show that the water of this area cannot be used for agriculture and drinking.

Considering the vast resources of natural gas and the reduction of oil resources and because of environmental and economical reasons, the use of natural gas has increased as an energy provider for the different parts of the industry. Rail transportation industry has greatly disregarded the utilization of natural gas. This article attempts to explain the advantages of the use of natural gas in locomotives and to discuss the existing technological issues. One of the fuels that can be used in locomotives is the liquefied natural gas (LNG). The article also discusses the technical issues related to the fuel replacement methods.

Today, more than 61 percent of Irans population lives in urban areas. This high national level of urbanization causes land use changes and environmental problems in most of the cities. In social, economic and environmental plans, the future generations problems should be premeditated. Improving the quality of life, protecting the urban environment, and the communitys way of life should be aimed at. Many of the cities are currently the fossil-fuel consumers, land users and waste producers. If these problems are to be overcome, city development patterns should be created. In the development process, we should give priority to the sustainability of ecological systems. Building the ecological city is a major contribution to better urban management and planning for both the citizens and the environment. The Ecological City proposes new ways of preserving and restoring the balance between the natural and the built environment in urban communities. To overcome the problems of big cities, the management of water supply, air quality, waste, energy use and land use issues of these cities should be considered. A range of practical strategies for improving the urban environment and restoring the health of urban ecosystems should be studied. This study leads us to create an ecological city. The goal of this paper is to provide a significant improvement for the environment and the quality of life in cities. So, this study provides: a suitable plan for managing cities and can be a source for urban planners, architects and local and national government officials.