فهرست مطالب

Environmental Research - Volume:6 Issue: 1, Winter 2012

International Journal Of Environmental Research
Volume:6 Issue: 1, Winter 2012

  • 364 صفحه،
  • تاریخ انتشار: 1390/10/10
  • تعداد عناوین: 35
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  • Sandeepk., Warrier, A.K., Harshavardhana, B.G., Shankar, R Page 1
    Iron oxide minerals in soils provide valuable insights into pedogenic processes. A wealth of such information has been obtained by rock magnetic investigations on temperate soils but similar studies on tropical soils are rare. Here, we report rock magnetic data on pristine soil profiles and surficial soils from five catchments in the tropical southern India and throw light on the pedogenic processes. We ruled out contributions from greigite, bacterial magnetite and anthropogenic sources; hence, the magnetic signal is mainly from the catchment, principally pedogenic and, thus, has a climatic signature embedded in it. The Pookot profile from a high rainfall (~4000 mm/year) region does not exhibit any magnetic enhancement at the surface. In fact, there is hardly any difference between surface and sub-surface samples, which reflects on its deeply weathered nature as a result of the high rainfall. The Shantisagara profile exhibits lessivage of magnetic minerals, resulting in a thick magnetically enhanced zone. It shows the highest χlf values among the five profiles studied. The Thimmannanayakanakere (TK) and Ayyanakere (AK) soil profiles do not exhibit any magnetic enhancement of top-soil. In fact, χlf values increase towards the profile-bottom, suggesting top-soil erosion, besides contribution of magnetic minerals from parent rocks. In the TK profile, there is a clear distinction between surface and sub-surface samples, the former being magnetically coarser grained. The Kurburukere profile exhibits moderate to strong χlf values and a mild magnetic enhancement at the surface.The data would be useful for establishing soil-sediment linkages for paleoclimatic studies of lake sediments.
  • Mhadhbil., Palancaa., Gharredt., Boumaiza, M Page 19
    Ría and coastal zone are, in particular, vulnerable to heavy metals pollution. Concentrations of 10 metals in liver, muscle and kidney of the sole (Solea vulgaris) from Ría of Vigo and its coastal zone (Spain) were measured from April 2006 to February 2007 and the relationships between fish size age and metal concentrations in the tissues was investigated. Concentrations of the heavy metals in examined fish ranged as follows: Cd (0.01- 0.7), Pb (0.1- 2.5), Hg (0.01- 0.7), Cu (3.3- 46.7), Zn (15- 274), As (3- 151), Se (0.9- 18.2), Mn (0.9- 9.76) μg/g dryweight. Kidney and liver showed the highest levels of Cd, Cu, Pb and Zn. The concentration of metals was significantly affected by the sampling site and fish tissues. Our results indicated that all heavy metals were found the highest in muscle tissue. A comparison of metals concentration in fishes from both sites showed higher bioaccumulation in the exemplars captured in Ría. This indicates that there is a trend of higher metal pollution level in the estuarine environment. Although, metals levels in the tissues in the area do not exceed contamination levels, measures are recommended for lowering heavy metals inputs into Ría of Vigo. Heavy metals in the edible parts of the investigated fish were in the permissible safety levels for human uses.
  • Uemura, Sh., Suzukis., Maruyama, Y. Harada, H Page 25
    The down-flow hanging sponge (DHS) reactor, which was developed for post-treatment of effluent from up-flow anaerobic sludge blanket (UASB) process treating sewage, uses polyurethane sponge as media to retain biomass. Wastewater is trickled from the top of the reactor and purified by microorganisms retained both inside and outside of the sponge media as the wastewater flows vertically down through the reactor. Three DHS reactors employing different sizes of sponge media with the same total sponge volume were used for the direct treatment of settled sewage. All the reactors exhibited excellent performance in removal of COD, ammonium nitrogen, and fecal coliform at a fixed hydraulic retention time of 2.0 h based on the sponge volume. It was shown that smaller sponge media produced better removal efficiencies for all the parameters listed above. The most reasonable explanation for this might be that smaller sponge media allows better oxygen uptake in the stream flowing down through the reactors.
  • Clementez., Castro, V. L., Jonsson, C. M.Fraceto, L. F Page 33
    The production and use of synthetic nanoparticles is growing rapidly, and therefore the presence of these materials in the environment seems inevitable. Titanium dioxide (TiO2) presents various possible uses in industry, cosmetics, and even in the treatment of contaminated environments. Studies about the potential ecotoxicological risks of TiO2 nanoparticles (nano-TiO2) have been published but their results are still inconclusive. It should be noted that the properties of the diverse nano-TiO2 must be considered in order to establish experimental models to study their toxicity to environmentally relevant species. Moreover, the lack of descriptions and characterization of nanoparticles, as well as differences in the experimental conditions employed, have been a compromising factor in the comparison of results obtained in various studies. Therefore, the purpose of this paper is to make a simple review of the principal properties of TiO2, especially in nanoparticulate form, which should be considered in aquatic toxicology studies, and a compilation of the works that have been published on the subject.
  • Madani, Sh., Ahmadianm., Khaliliaraghim., Rahbar, F Page 51
    This paper is concerned with the economic valuation of the coral reef within Kish Island in Persian Gulf of Iran. For calculating this value, all components of use and non-use values are estimated and then according to each of them, suitable method has applied. Many different evaluation tools such as contingent valuation method, zonal travel cost method, replacement cost, avoided cost method, value at risk method are used. The semi non parametric distribution free estimator for calculating the contingent valuation method is applied. The probability of willingness to pay the same as the probability of accepting bids is estimated by using data based on questioners approach using stated preference method. The result indicates that the total economic value of this unique ecosystem in Kish Island is at least 14.6 million dollar per year, showing the importance of conservation value of the ecosystem. Its largest component of total economic value is about 62 percent attributed to the recreational value. This is followed by conservation value which is about 23 percent of the economic value. Since coastal protection and waste assimilation functions of coral reef are 10 percent, it is also suitable factor in illustrating total economic value. The economic value for each hectare of this ecosystem in Kish Island is US$ 237,000 in 2009.
  • Fotouhia., Montazeri, Gh. M Page 61
    In this paper, vehicle’s fuel consumption and exhaust emissions are investigated in different driving conditions based on driving segments clustering. Driving data collection is performed using global positioning systems in real traffic conditions. The driving data is clustered into five groups using k-means clustering technique. Vehicle’s fuel consumption and exhaust emissions (i.e. HC, NOx and CO) are investigated in different driving conditions using computer simulations. The relationship between driving features and vehicle’s fuel consumption and exhaust emissions is also presented. According to the simulation results, vehicle’s fuel consumption decreases as average velocity increases from very congested traffic condition to freeway traffic condition. The most HC is produced is low speeds. The results also demonstrate that high accelerations and decelerations cause high amount of NOx. About the CO emission, a moderate driving in which the velocity and accelerations are not very high or very low, leads to the least amount of CO.
  • Mossalanejad, A Page 71
    Today, Economic and environmental performance are tightly closed to each other. The natural environment plays an important role in supporting economic activity; directly, by providing resources and raw materials such as water, timber and minerals that are required as inputs for the production of goods and services; and indirectly, through services provided by ecosystems including carbon sequestration, water purification, managing flood risks, and nutrient cycling. Natural resources are, therefore, vital for securing economic growth and development, not just today but for future generations. Economic growth has also provided developing countries the opportunity to improve the quality of life of their citizens, and to balance the environmental challenges they face. Investment, aid and demand for imports from advanced economies all have an important role in supporting economic growth and development through the world. The main objective of this paper is to highlight the role of the natural environment in supporting and contributing to economic growth, and the role of environmental policy in achieving improved environmental outcomes in ways that are compatible with the long-term health and stability of the economy. It does not try to answer the question of what the sustainable level of economic growth might be, but instead reviews the evidence and sets out an approach for securing environmentally sustainable economic growth for current and future generations.
  • Lalevicb., Raicevicv., Kikovicd., Jovanovicl., Surlan-Momirovicg., Jovicj., Talaie, A. R., Morina, F Page 81
    Methyl tertiary butyl ether (MTBE) belongs to the group of gasoline oxygenates and persistent environment contaminants, and shows potential for biodegradation in aerobic and anaerobic conditions, through application of pure microbial cultures. Presented research shows that indigenous bacterial isolates 6sy and 24p, selected from oil hydrocarbons-contaminated environments, were capable of utilizing MTBE as sole carbon and energy source. Based on 16S rDNA sequence analysis, bacterial isolates 6sy and 24p were identified as Staphylococcus saprophyticus subsp. saprophyticus and Pseudomonas sp., respectively. The MTBE biodegradation rate was affected by longevity of incubation period and initial MTBE concentration. After 3 weeks of incubation at 25°C in a dark, the removal rates of initial 25 and 125 ppm MTBE concentrations by Staphylococcus saprophyticus 6sy were found to be 97, and 63%, respectively, while efficiency of Pseudomonas sp. in degradation of indicated concentrations was 96, and 40%, respectively. Both bacterial isolates were able to grow in MTBE-containing growth medium. Highest growth rate of bacterial isolates was observed at the end of incubation period. The presented results indicated the potential of these bacterial isolates in bioremediation of MTBE-contaminated environments.
  • DiviŠp., Mach, Aacutet., J., Szkanderar., DoČekalov, Aacute, H Page 87
    This work summarized the results of a long term monitoring programme performed downstream on the Morava river (Czech Republic). During this programme the total dissolved concentrations and bioavailable fraction of selected metals (Zn, Pb, Ni, Cu) were monitored. For the determination of bioavailable metals species, diffusive gradients in thin films technique (DGT) together with moss bags technique utilizing Fontinalis antipyretica moss species were used. All of the measured metal concentrations were compared with an amount of accumulated mass by Fontinalis antipyretica, represented as a concentration factor, CF. Obtained results shown that further investigation of DGT technique and metal accumulation processes by Fontinalis antipyretica is needed to conclude if the DGT technique is a good alternative for the biomonitoring technique using Fontinalis antipyretica moss bags as a means to measure (bio)available metal concentrations in natural water. Significant correlation with CF was found in the case of DGTZn and DGTPb concentrations. On the other site, accumulated mass of Cu by Fontinalis antipyretica correlated significantly with total dissolved concentration of Cu. In the case of Ni no correlation was found between total dissolved Ni concentrations, DGTNi concentration and CF of Fontinalis antipyretica.
  • Kim, D. K., Jeong, K. S., Mckay, R. I. B., Chon, T. S., Joo, G. J. Page 95
    In the regulated Nakdong River, algal proliferations are annually observed in some seasons, with cyanobacteria (Microcystis aeruginosa) appearing in summer and diatom blooms (Stephanodiscus hantzschii) in winter. This study aims to develop two ecological models forecasting future chlorophyll a at two time-steps (one-week and one-year forecasts), using recurrent neural networks tuned by genetic algorithm (GA-RNN). A moving average (MA) method pre-processes the data for both short- and long-term forecasting to evaluate the effect of noise downscaling on model predictability and to estimate its usefulness and trend prediction for management purposes. Twenty-five physicochemical and biological components (e.g. water temperature, DO, pH, dams discharge, river flow, rainfall, zooplankton abundance, nutrient concentration, etc. from 1994 to 2006) are used as input variables to predict chlorophyll a. GA-RNN models show a satisfactory level of performance for both predictions. Using genetic operations in the network training enables us to avoid numerous trial-and-error model constructions. MA-smoothed data improves the predictivity of models by removing residuals in the data prediction and enhancing the trend of time-series patterns. The results demonstrate efficient development of ecological models through selecting appropriate network structures. Data pre-processing with MA helps in forecasting long-term seasonality and trend of chlorophyll a, an important outcome for decision makers because it provides more reaction time to establish and control management strategies.
  • Mzoughin., Chouba, L Page 109
    In the framework of the Mytilos project (Interreg IIIB Medocc), international research cruises were carried out in 2006 in order to evaluate the level of Heavy metals and polycyclic aromatic hydrocarbons (PAH) along the coast of the western basin of the Mediterranean Sea. Caged mussels (Mytilus galloprovincialis)were placed in situ at six sites in the North coast of Tunisia. Results showed total PAH levels were in the range 45.6-241.6 ng/g dry weight (dw). The ranges of trace metals concentrations expressed in μg/gdw are: Hg (0.1-0.2), Pb (0.4-0.7), Cd (0.9-2.9), Cu (2.9-3.9), Fe (117-248) and Zn (250-426). Higher concentrations were observed at Rades, La Galite and Tabarka which can be attributed to the industrial activities implanted in the coast of Algeria and in the city of Rades. Concentrations of PAH, Cd, Pb, Fe and Zn are generally differentfrom initial concentrations (before caging), depending on the adaptability of transplanted mussels to be used as bio-indicator of contaminants. Yet bio-monitoring using mussels give information on compound bioavailability which depends on their ability to accumulate contaminants in its tissue.
  • Shafieiyouns., Ebadit., Nikazar M Page 119
    Leachate treatment from municipal landfills has been always a major anxiety in waste management due to its high level of various contaminations. In this paper the effect of Nanosized Zero Valent Iron particles (NZVI) in Fenton process for the treatment of high COD strength landfill leachate was scrutinized. The results corroborated this procedure was fast and efficient. In fact, about 87% of initial COD (38 g/L) was reduced in an hour. The various operation conditions such as pH, initial H2O2 concentration, H2O2/Fe molar ratio and temperature in a batch reactor were investigated. The optimum condition was obtained at pH value of 2, temperature of 40°C and H2O2 to Fe molar ratio equal to 39 by using only 0.07 M of NZVI. In such conditions, 0.08 M H2O2 for the removal of 1 g/L of COD was needed. Furthermore, hydrogen peroxide consumption after Fenton process was evaluated and it was found that it had a direct relationship with COD removal efficiency.
  • Mahmoudkhanir., Hassani, A. H., Torabian, A. Borghei, S. M Page 129
    one of the most important concerns in Tehran municipal landfill is the production of leachate and its potential for water resources pollution, this study was undertaken to examine feasibility of biological and physico/chemical treating of high-strength landfill leachate that was collected from Tehran municipal landfill. Average COD of the leachate in aerobic submerged membrane bioreactor is 68000 mg/L. The reactor with a working volume of 175 L, having membrane module (Hollow fiber) with pore size of 0.1 μm coupled with reverse osmosis with pore size of 0.001 μm was used in this study. The dissolved oxygen (DO) concentration was maintained at 3.2 mg/L and solid retention times (SRTs) and hydraulic retention times (HRT) were controlled at 55 and 15 days respectively. the average Membrane Bioreactor effluent COD was 1733 mg/L with average removal efficiency of 97.46%. The average NH 4 –N removal efficiencies was 99%. On the other hand, an almost complete nitrification was achieved during this period. PO4 –P concentration in the effluent was low and its average removal efficiency was as high as 90%; especially during the operation period. The averages reverse osmosis (RO) effluent COD was 335 mg/L with average removal efficiency of 99.13%. PO4-P concentration in the RO effluent was 0.86 mg/L and its average removal efficiency was 99.33%. The use of Membrane technologies, more especially reverse osmosis offers the best solution of achieving full purification with average COD removal efficiency of 99% and solving the problem of water resources pollution.
  • Mhadhbil., Boumaiza, M Page 139
    In the present study, the toxic effects on the embryos and larvae of the turbot were used as a model to investigate the diazinon, which contaminates aquatic ecosystems. The number of dead embryos significantly increased in response to diazinon concentrations 0.2, 0.4, 0.8, 1.6, 3.2, and 7.4 mg/L. The 48h LC50 value of diazinon for turbot embryos was estimated at 1.85 mg/L. Dose–response decreases in hatching success were recorded as 97, 92.4, 80.3, 60.3, 38.7 and 27.1%, respectively. The number of dead larvae significantly increased with increasing diazinon concentrations exposed for 24–96 h (p < 0.05). The 24, 48, 72 and 96h LC50 values of diazinon for turbot larvae were estimated at 4.8 (6.4-5.12), 3.3 (4.73-2.52), 2.1 (3.29- 1.65) and 1.23 (0.87–2.38) mg/L, respectively. There were significant differences in the LC50 values obtained at different exposure times (p <0.05). Diazinon caused lethal toxicity as well as nonlethal malformations during embryo-larvae development.
  • Mescib., Elevli, S Page 145
    Recently full factorial design approach has been used to assess the recycling potential of a given waste. The objective of this study is to identify the significant factors and interactions involved in maximizing compressive strength of concrete when chromium waste is used as admixture. In this respect, experimental factors at two levels, which are admixture type (chromite/ chromite+ superplastizer), admixture percentage (5- 15%) and cure duration (7-28 days), are selected as possible candidates affecting the compressive strength. The modeling technique presented in this paper is based on 23 full factor experimental design and can easily be implemented to see the effect of any input factor on a given response variable. According to the full factorial analysis, at the 5% percentage level when Naphtalene sulfonate is added to concrete with chromite waste, the compressive strength will be good enough after 28 days. The results demonstrate that chromite waste after neutralization can be used in construction industry.
  • Kiteresi, L.I., Okuku, E.O., Mwangi, S. N., Ohowab., Wanjeri, V.O., Okumus., Mkono, M. Page 151
    Phytoplankton communities play a significant role in the oceanic biological pump by forming the base of the trophic structure. Increase in nutrients loading affects spatial and temporal distribution of phytoplankton. This study examined the phytoplankton community structure and ecological indices in relation to nutrients dynamics in both estuarine and oceanic areas of Ramisi-Vanga systems along the Kenyan coast. Surface water samples were collected and analysed for nutrients (PO4 3--P, NO3 --N and NH4 +-N) and phytoplankton abundance and community structure. This study reported very diverse phytoplankton community structure consisting of 88 taxa that were dominated by Chaetoceros sp., Coscinodiscus sp., Nitzschia sp., Pseudo-nitzschia sp., Alexandrium sp., Protoperidium sp. and Prorocentrum sp that are among the potentially harmful algae. Diatoms were the most abundant taxa in Ramisi-Vanga system. Phytoplankton abundance was found to be higher in the estuarine systems (1182.06±149.14 cells/L) as compared to the oceanic systems (551.99±166.70 cells/L) with high abundance observed in May for oceanic and estuarine systems. Shannon Weiner’s species diversity index was greater than 2 in both oceanic and estuarine systems. Phytoplankton species’ abundance, composition and diversity were found to be influenced by the availability of NH4 +-N, NO3 --N and PO4 3--P. Phytoplankton cell density was below 4000 cells/ L, thus, this study has classified Ramisi-Vanga system as an oligotrophic system implying that the current level of land based activities are not having significant impacts on the phytoplankton communities.
  • Mirbagheri, S. A., Sadrnejad, S.A., Hashemi Monfared, S. A Page 163
    IPhytoplankton and zooplankton concentrations in Pishin reservoir are predicted employing a three-dimensional numerical model in this paper. Modeling is performed using a numerical model based on mass transport equation. Advection, diffusion and source/sink processes are considered as separate subroutines for predicting the concentrations of phytoplankton and zooplankton in the reservoir. Finite volume method is used for solving the governing equations of water quality and water flow. The model is adopted for drought periods and dry climates. Water flow in the reservoir is simulated by Fluent software that is a finite volume numerical model. The model also uses a sub-model for compatibility providing of geometry between software and water quality model. A one-year period of experimental works and sampling is done in the study area. Phytoplankton and zooplankton cycles are used to determine the sources and sinks. Standard methods are chosen for experimentation. The concentrations of phytoplankton and zooplankton are calculated and measured in a one-year period. The concentrations of phytoplankton and zooplankton decrease in the depth of water and the decease rate is not linear. Also the concentrations are increase in the times after the maximum floods because of the inflows contain high amounts of nutrients. The calculated values by the model are in good agreement with measured values of laboratory works. It was concluded that the model can be used for water quality prediction in such aquatic environments.
  • Kargarm., Khorasani, N. A., Karamim., Rafiee, G. H., Naseh, R Page 173
    The contents of As, Cd, Cu and Mo were determined in soil surrounding Meyduk tailings dam based on 21 surface soil samples. Assessment of toxic element pollution in studied soil samples needs knowledge of pre-anthropogenic metal concentration to act as a reference against which measured values could be compared. Estimating the background values was executed by sampling rocks adjacent to soil sampling stations. Various indices including enrichment factor (EF), pollution load index (PLI), modified contamination degree (mCd) and geoaccumulation index (Igeo) were used for determining the contamination level of soil in the vicinity of tailings impoundment under the effect of the tailings dust. Anthropogenic pollution was diagnosed from natural one by sequential extraction done by Tessier et al. method and calculating pollution intensity index (IPOLL). The results indicate a significant upward enrichment in northeastern and southwestern surface soil around the tailings dam for Cd and Cu. The dominant wind direction demonstrated that only the contamination of southwestern soil around the tailings dam would be attributed to tailings dust while the dispersive dusts scattered after the mine explosions generally affected the northeastern part.
  • Kalhoria., Jafari, H. R., Yavari, A. R., ProhiĆe., Ahmadzadeh Kokya, T Page 185
    This study was conducted in Assaluyeh region, southwest of Iran to show utilization and efficiency of sequential extraction analysis in environmental impact studies using soil and related regolith materials as sample media. In order to investigate distribution of heavy metals, optimized BCR (Community Bureau of Reference) sequential extraction analysis method was used. In this caseeight representative samples which state all types of different regolith materials in the area were investigated. Total concentration and chemical partitioning of a number of elements (Pb, Cu, Zn, Cr, Mn and Fe) were studied to cover all spectral from typical anthropogenic elements, lead and copper, elements of assumed mixed origin, chromium and zinc, to mostly lithogenic elements, iron and manganese. Results stated that the concentrations of each chemical phase extracted from samples are below the total concentration of each element.The results could be used to establish best media indicators for environmental studies with dependence on type of elements determined in regolith material. Using sequential extraction analysis, the association of particular elements with geochemical phases in soils and related materials was investigated as well asthe importance of particular phases in the scavenging of heavy metals. Results showed that the organic and sulphide phase was less important in scavenging mechanism –in spite of industrial and petrochemical activities in the study area– than exchangeable and carbonate fraction, which showed to be most important phase with respect to metal scavenging capacity.
  • Lih., Wangy., Shi, L.Q., Mij., Songd., Pan, X. J Page 195
    Dianchi Lake is one of the most three seriously eutrophic lakes in China. In the present study, the phosphorus (P) and nitrogen (N) fractions in 37 surface sediments samples collected in the Dianchi Lake were investigated. The total phophorus (TP) in sediments was divided into two parts: inorganic P (IP) and residual P (Res-P). The results showed that the total phosphorus content in surface sediments ranged from 1465.27 to 3650.12 mg/kg, IP was the major component of TP and the Ca bound P was the main fraction of IP. The bio-available phosphorus (BAP) in Dianchi Lake was first estimated in this study. BAP ranged from 215.66 to 678.02 mg/kgand the mean concentration was 382.78±89.77 mg/kgfor all 37 samples. The nitrogen fractions for the whole Dianchi Lake were firstly studied. It was shown that the sediment had been an important N nutrient source of the water, owing to the high content of transferable nitrogen forms in the sediment.
  • Ashraf, M. A., Maah, M. J., Yusoff, I Page 209
    This study has been carried out to determine the accumulation of heavy metals (arsenic, copper, lead, tin and zinc) in fish samples collected from former tin mining catchment. Total eight types of fish family having fifteen different species are identified. Cyperinidae is the most abundant family with eight different species found in the catchment. Fish samples were analysed by using inductively coupled plasma optical emission spectrophotometer ICP-OES. The accuracy of method is validated by certified reference material. The highest level of arsenic was observed in Hampala macrolepidota while Osteochilus hasselti shows the least. For Copper concentrations, the maximum was obtained in Mastacembelus armatus and the minimum in Oxyeleotris marmorata. High levels of lead, tin and zinc were found in the Rasbora elegans, Trichogaster trichopterus, Oxyeleotris marmorata respectively while Macrobrachium resenbergii,Mastacembelus armatus, Rasbora elegans had the least concentrations. The sequence of order of the heavy metals measured was Sn > Pb >Zn > Cu> As, respectively. The results showed elevated levels of tin, led and zinc in all the fish samples although copper and arsenic were available in relatively low concentration in the most samples. Sn, Pb, and Zn concentration in the samples were greater than Malaysia food act permissible levels. Hazard index < 1 suggests unlikely adverse health effects whereas HI > 1 suggests the probability of adverse health effects. Although the heavy metals analysed in the catchment did not pose any immediate health risk to humans but due to the bioaccumulation and magnification of these heavy metals in humans, it is essential to safeguard levels of the metals in the environment.
  • Arias, A.H., Piccolo, M.C., Spetter, C.V., Freije, R.H., Marcovecchio, J.E Page 219
    Both climate change and anthropogenic impact are creating a dynamic of continuous changes in ecosystems. While the expected consequences of these changes are global, the occurrence of extreme events and specific environmental problems are usually local or regional phenomenon. In particular, the coastal ecosystems are among the first vulnerable areas to show those changes; in spite of this, are the least studied. The Bahia Blanca estuary, Argentina, is located at 38º 40´ S and 62º 09´ W with an area of 2300 km2. Along the northern shore of the estuary it is found the most important deepwater harbor of the country, where most of the agricultural and industrial products are exported. For the first time, based on multi decadal oceanographic monitoring and meteorological data of this ecosystem, a co-relational analysis approach was outlined considering several documented changes at various trophic levels; namely, phytoplankton and zooplankton assemblages, commercial crustaceans and fisheries. As results, several novel emerging hypotheses regarding cause-andeffect relationships were formulated. These unprecedented findings represent substantial information for the focus of the future ecosystem management and research, revealing gaps in the present knowledge of the coastal ecosystem which can be extrapolated to other worldwide coastal systems.
  • Selvamuruganm., Doraisamyp., Maheswarim., Nandakumar, N. B Page 235
    In this paper, startup performance of Upflow Anaerobic Hybrid Reactor and Upflow Anaerobic Sludge Blanket reactors in anaerobic treatment of distillery spentwash has been studied under identical conditions of operation. Various effluent characteristics like pH, Electrical Conductivity, Chemical Oxygen Demand, Biochemical Oxygen Demand and Total Solids and other process parameters like biogas production and methane per cent in biogas were studied until the attainment of steady state. The startup of the reactors has been completed and steady state condition attained on 25th day of reactor operation in UAHR and 34th day in UASB reactor. The treated effluent characteristics of both reactors were fairly steady after attaining the steady state condition. The pH of treated effluent during steady state condition was almost neutral for both reactors even though the influent had an acidic pH. The maximum COD, BOD and TS removal efficiencies were as high as 79.60%, 87.39% and 69.96% in UAHR as compared with UASB of 72.98%, 81.34% and 66.23%, respectively during the steady state period. The maximum volumetric gas production of 149 L m-3 produced more in UAHR than in UASB reactor during steady state condition. The population of total anaerobic bacteria and methanogenic bacteria also more as that of the other parameters in UAHR than in UASB reactor and it were 55.2 x 103 ml-1 and 40.0 x 102 ml-1 respectively in UAHR. It is found that from an overall assessment the UAHR has proved superior in its performance compared to the UASB reactor during the startup process.
  • Spanous., Tsegenidik., Georgiadis, Th Page 245
    Visitor management is considered important for the sustainable development of protected areas as the presence of visitors may cause negative impacts on wildlife and vegetation. Within this framework, visitor impacts and perceptions are considered critical for decision-making and planning of future management regimes. This paper resumes opinions of visitors of the Valley of Butterflies in Rhodes Island, Greece, a very popular tourist destination in both national and international level, with more than 300,000 visitors per year. These opinions record perceptions on the environmental impacts of eco-tourism in the Valley and are necessary for the formulation and implementation of a visitor management strategy in the area. Descriptive statistics are estimated, as well as a probit model exploring factors affecting visitors’ satisfaction. Results call for more information and education of the visitors about the Valley’s conservation and ecological value, better facilities and services provided, site hardening and a better policy of prices.
  • Shahriarit., Nabi Bidhendig., Shahriari, Sh Page 259
    In the current study, the efficiency of starch and Plantago ovata extract as coagulant aids is compared in water turbidity removal. The coagulant is ferric chloride and the experiments are run in two ranges of pH 7 and 8. The achieved results of turbidity removal in different turbidity levels of 100, 50 and 20 NTU caused by different concentrations of starch and P.ovata as coagulant aids besides ferric chloride as the main coagulant are compared. According to the achieved results, the use of P.ovata or starch as the coagulant aid may play a key role in reducing the amount of FeCl3 as the main coagulant and consequently decreasing the generated sludge. Furthermore, the remarkable turbidity removal efficiency gained when these coagulant aids are used in comparison with the case when no coagulant aid is introduced is also of interest. Generally, the both coagulant aids seem to be more efficient in pH value of 7 rather than 8. Although both coagulant aids used in this study manifested acceptable turbidity removal efficiencies, P.ovata showed higher capabilities of removal in different turbidity levels and pH values in comparison with starch.
  • Subramanyam, B.Ashutosh, D Page 265
    Liquid-phases adsorption equilibrium of phenol onto two naturally available soils namely Kalathur soil (Kr) and Adhanur soil (Ar) were studied. The experimental data were analyzed using fourteen isotherm models, ranging from single-parametric model to multi-parametric models (up to 5 parameters) of the system. Results show that in general the accuracy of models to fit experimental data improves with the degree of freedom. To understand the mechanism involved with different types of sorbate-sorbent system as well as to find out the best fitting isotherm model, the correlation coefficients, and average percentage error and student t-test were carried out. Temkin isotherm model, Langmuir-Freundlich isotherm model and Fritz- Schlunder model as well as Baudu model were found to be the best fit models amongst the two-parametric models, three parametric models and four parametric isotherms modeling, respectively. This study brings out the need of simultaneous solution of multi-parametric equations (using relevant softwares, MATLAB, in present case) than solution of their linearized forms, which is mostly followed by contemporary investigators.
  • Nejadkoorkif., Baroutian, S Page 277
    Life style and life expectancy of inhabitants have been affected by the increase of particulate matter 10 micrometers or less in diameter (PM10) in cities and this is why maximum PM10 concentrations have received extensive attention. An early notice system for PM10 concentrations necessitates an accurate forecasting of the pollutant. In the current study an Artificial Neural Network was used to estimate maximum PM10 concentrations 24-h ahead in Tehran. Meteorological and gaseous pollutants from different air quality monitoring stations and meteorological sites were input into the model. Feed-forward back propagation neural network was applied with the hyperbolic tangent sigmoid activation function and the Levenberg–Marquardt optimization method. Results revealed that forecasting PM10 in all sites appeared to be promising with an index of agreement of up to 0.83. It was also demonstrated that Artificial Neural Networks can prioritize and rank the performance of individual monitoring sites in the air quality monitoring network.
  • Rahman, M. M., Al-Malack, M. H Page 285
    A lab-scale cross flow membrane bioreactor (CF-MBR) was operated to determine the biokinetic coefficients under MLSS concentrations of 5000 and 3000 mg/L. The investigation showed that the yield (Y), the endogenous decay coefficient (kd), the maximum specific growth rate (μm) and the saturation constant (KS) were 0.276 mg/mg, 0.07 /day, 0.653 /day, and 396.62 mg COD/L respectively for MLSS 5000 mg/L, and 0.222 mg/mg, 0.09 /day, 1.2 /day, and 659.45 mg COD/L for MLSS 3000 mg/L. The values of kinetic coefficients were within the normal range of the activated sludge process found in the literature, except the values of Y. However, value of Y increased with the increase of MLSS. Kinetic parameters determined from CF-MBR process were used to simulate the effluent COD. The simulation study showed good agreement between model prediction and experimental data. Sensitivity analysis was carried out to determine influence of biokinetic parameters on the effluent substrate concentration. From the analysis, it was evident that kd and KS were directly proportional to the effluent substrate concentration, while μm was inversely proportional.
  • Soni, A. B., Keshava., Vermav., Suresh, S Page 297
    Present study deals with the adsorption of glycolic acid (GA) from aqueous solutions by using bagasse fly ash (BFA). BFA is a solid waste generated from bagasse fired boilers and can be used as an adsorbent. Batch adsorption studies were carried out to evaluate the effect of various parameters like adsorbent dose, contact time, initial concentration and temperature on the removal of GA from aqueous solutions. For the selected dosage, it was found that the adsorption increases with increase in BFA doses and decreases with increase in acid concentration. The effect of contact time on removal shows that the adsorption of glycolic acid on BFA is very fast. The kinetics of the sorption of GA was well represented by Elovich model, first order, pseudo-second order and Weber and Morris intra-particle diffusion model. The adsorption isotherm analyses were also carried out by using Langmuir and Freundlich isotherm equations. Freundlich equation was found satisfactory to represent the equilibrium data. Thermodynamic studies revealed that the adsorption of GA on BFA is exothermic in nature.
  • Mohebbif., Mohsenpour Azaria., Heidarim., Asem, A Page 309
    Occurances of cyanobacterial bloom typically appear in eutrophic lakes which either have been affected by anthropogenic nutrient loading or are naturally rich in nutrients. Microcystis blooms have been reported all over the world in freshwater ecosystems mainly due to increased population which results in increased the waste water production. The aim of this study was to recognize the basic reasons of Microcystis aeruginosa bloom in Aras reservoir. Water temperature, pH, DO, EC, TN, N-No2, N-No3, P-Po4, chl a and the number of Microcystis colonies were determined. The effects of these parameters on the microcystis increased growth was examined. Though we could not strictly relate a few other factors to this phenomenon, higher water temperature, pH and DO in the sampling site i.e. 27° C, 9.16 and 17.2 mg/L respectively, surely favored the M.aeruginosa bloom. In brief, preventing or reducing the nutrients flow into the reservoir should be considered as a priority in order to reduce Microcystis scum forming colonies.
  • Okuku, E.O., Peter, H. K. Page 313
    The study aimed to come up with a list of specific macroalgae species, which could be used to biomonitor specific metal elements in the coastal waters of East Africa. Water extraction, EDTA, aqua regia extraction and optimized BCR 3-step sequential extracts were used to mimic bioavailable metals under various environmental conditions. The results indicated that Ulva lactuca could be used as a biomonitor to predict BCR 3-step sequential bioavailable Al, Cd, Co, Fe, Mn, Zn and Ni whereas Sargassum species could be used as a biomonitor for BCR 3-step sequential bioavailable Co, Cu, Fe, Mn and Zn. In Sargassum spp. only Co showed significant correlation with concentration in sediment’s aqua regia extracted metals whereas in Ulva lactuca only Al, Co, Cu and Fe showed significant correlation with total metals extracted through aqua regia procedure. This study therefore recommends the use of Ulva lactuca and Sargassum for biomonitoring of Al, Cd, Co, Fe, Mn, Zn, Ni and Co, Cu, Fe, Mn, Zn respectively. The study recommends the use of labile fraction of BCR sequential extraction for screening of macroalgae to be used for heavy metal pollution monitoring in East Africa region.
  • Arslant., Yilmazv., Aksoy, H. K Page 323
    In this study, the effect of environmental concern, attitudes and behaviors of the university students on the environmentally conscious purchasing behavior was investigated with the help of Structural Equation Model (SEM). SEM is an effective data analysis tool that expresses the complicated causative relations between the latent variables. In this study, we collected the data from 400 university students by means of a survey. The results of this research showed that environmental attitudes, environmental behavior and green product awareness have a positive effect on environmentally conscious purchasing behavior. The developed model showed that, environmental concern explains 48% of the variation in the environmental attitudes and 28% of the product recovery awareness; environmental attitudes and product recovery awareness explain 55% of green product awareness; environmental attitudes explains 44% of the variation in the environmental behavior; environmental attitudes, green product awareness and environmental behavior explain 74% of the variation in the environmentally conscious purchasing behavior.
  • Solids Adlm., Sheng, K.C., Xia, Y. H., Gharibia., Chen, X Page 335
    Plug-flow digesters with periodic loading mechanism are more enthusiastic than fully mechanized digestion plants for the majority of small or medium scale farms according to the costs and operational complexities. A dual-compartment plug-flow reactor equipped with a passive heating system was designed and experimentally operated by purpose of demonstrating a simple and low cost technology for handling the biodegradable agricultural wastes. The reactor was successfully started up with pig feces as feedstock under a quasi-continuous loading and semi-dry condition with an average total solids content of 12.8% inside the digester and an average organic loading rate of 2.06kg-VS/(m3.d). The start-up phase was followed by co-digestion of pig feces and pre-treated cotton stalk. Even though the digester actually worked at a temperature range 12 to 30% below the optimal mesophilic level, acceptable rates of methane generation and VS destruction were observed. The biogas and methane yield were measured for single digestion stage as 0.332 and 0.202 m3/(kg-added VS) and for co-digestion stage as 0.482 and 0.325 m3/(kg-added VS) respectively. The cumulative biogas production data demonstrated a reasonable correlation (R2 over 0.99) with a simplified consecutive kinetic model.
  • Castro-GutiÉrrez, V. M., Rodr, Iacute, Guez-Rodr, Iacute, Guez, C. E., Vargas-Azofeifa Page 345
    An aquifer located within a petroleum processing plant in Moín, Costa Rica, suffers hydrocarbon pollution. This study aimed to determine the ability of indigenous microorganisms from this site to degrade polycyclic aromatic hydrocarbons (PAHs) to evaluate the feasibility of an eventual bioremediation process. Aerobic conditions were found in the aquifer, while microbial analyses of the groundwater indicated the presence of important hydrocarbon-degrading populations. Sixteen PAH-degrading strains were isolated with the ability to grow on naphthalene (5 strains), phenanthrene (3), fluorene (6) and pyrene (2). Most of the identified isolates belonged to the genus Pseudomonas, although, Comamonas, Sphingomonas Stenotrophomonas and Delftia were also found. A mixture of selected strains was evaluated by its performance of PAH degradation in soil-slurry systems, where efficiency of removal was naphthalene > fluorene > phenanthrene > pyrene. This study is an initial approach to evaluate the feasibility of applying a bioremediation process in the contaminated site.
  • Lahijanian, A Page 353
    Aim of the present research was to design a proper model for management of knowledge in environmental organizations of country. In study of the model, suitability of the proposed model was researched by asking views of directors, deputies, managers of groups and scientific board members of environmental organizations of country. For this purpose, with review of research literature, insight process, independent technology process and alteration technology process, knowledge solution process, knowledge spiral process and knowledge management conceptual process, principal elements of model and components were determined by examination of models and theories of joint process in the learner organizations. Later, the model was proposed using questionnaire. Reliability of questionnaire was calculated 94.75 % and 93.73% by means of retesting method and Crown Bach’s method, respectively. Admissibility of questionnaire was also determined by admissibility of content thereof and primary implementation (asking views of 30 of directors, deputies, managers of groups in environmental organizations of country). Determination of admissibility, durability and amendments were followed by implementation of the proposed model in random selected statistical sample consisting of 360 individuals from 4 groups of directors, deputies, managers of groups and scientific board members in environmental organizations of country. The inputs were collected by means of descriptive statistics (frequency distribution tables and diagrams), conclusive statistics methods including Pearson correlation co-efficient matrix for the relation between components. Then, Anova (analysis of variance) the four groups under study, extraction and operative analysis and principal component analysis were performed using the SPSS software and the proposed model, with scale of 6.15 out of 7, was confirmed. Principal finding of present research was introduction of a proper model for knowledge management to be used in environmental organizations of country that consists of philosophy and aims, theoretical fundaments, and model implementation steps.