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Imposex in Thais gradata as a Biomarker for TBT Contamination on the Southern Coast of Peninsular Malaysia
2010
Mohamat-Yusuff, Ferdaus | Zulkifli, Syaizwan Zahmir | Ismail, Ahmad | Harino, Hiroya | Yusoff, Mohd Kamil | Arai, Takaomi
Thais gradata samples were collected from six locations along the southern shores of Peninsular Malaysia and analyzed for imposex incidence and organotin (butyltins (BTs), including tributyltin, dibutyltin, and monobutyltin, and phenyltins (PTs), including triphenyltin, diphenyltin, and monophenyltin concentrations), in tissue burden. On average, the BT levels were found to be higher than the levels reported a year before for other biota. In contrast, the PT compounds were found to be lower than in the previous report. The present study also classified the morphological expressions of the imposex scheme for this species into seven stages (stage 0 to stage 6) by observing the development of vas deference sequence (VDS) and penis bulk. This latest imposex scheme clearly indicates the mechanism of VDS growth, the structural changes from penis bulk to a penis with flagellum, and from a normal vaginal opening to a swollen vaginal opening. The degree of imposex was assessed using the vas deference sequence index and the percentage of females possessing the imposex characteristics. It was found that locations possessing high imposex levels also tended to show high BT levels in the snail tissue samples. However, correlation analysis did not show a significant relationship among the two parameters. A better result could be obtained if more samples and sampling locations were added in order to prove the hypothesis. The nonsignificant correlation between the shell height and any of the organotin compounds, along with no significant differences between BT levels in female and lower imposex stage samples, suggests that the BT concentration detected was a recent contamination.
显示更多 [+] 显示较少 [-]Decolorization of Synthetic Dyes and Textile Effluents by Basidiomycetous Fungi
2010
Diwaniyan, Sarika | Kharb, Deepti | Raghukumar, Chandralata | Kuhad, Ramesh Chander
Decolorization of six synthetic dyes and two raw textile effluents (A and B) by eight basidiomycetous fungi was investigated. Among eight basidiomycetous fungi, fungal isolate RCK-1 decolorized textile effluent A maximally (42%), while fungal isolate RCK-3 was found to decolorize more of Congo Red (69%), Xylidine Ponceau 2R (100%), Poly R-478 (96%), Indigo Carmine (99%), Lissamine Green B (90%), Toluidine Blue (57%) and textile effluent B (54%), than the rest of fungi. Percentage decolorization of all synthetic dyes and textile effluents by the new fungal isolates RCK-1 and RCK-3 was higher compared to the most widely studied simultaneous lignin degrader, Phanerochaete chrysosporium and selective lignin degrader, Pycnoporus cinnabarinus, when tested in liquid cultures. A statistically significant positive correlation between laccase production and decolorization of dyes and effluents was obtained as compared to other ligninolytic enzymes (lignin peroxidase and manganese peroxidase) production. This showed the importance of the differential contribution of the different ligninolytic enzymes towards the decolorization of the synthetic dyes and textile effluents. The substantially higher ligninolytic enzyme production by the fungal isolates RCK-1 and RCK-3 also suggested their potential use for textile effluent treatment and other possible biotechnological applications.
显示更多 [+] 显示较少 [-]Atmospheric Deposition of Nitrogen and Sulfur in the Yellow Sea Region: Significance of Long-Range Transport in East Asia
2010
Kim, J (Jin-Yong) | Ghim, Y. S. | Lee, S. B. | Moon, K. C. | Shim, S.-G. | Bae, G. N. | Yoon, S.-C.
The amounts of nitrogen and sulfur deposited in the region of the Yellow Sea in both dry and wet forms were estimated focusing on the period between 1999 and 2000. Dry deposition fluxes were obtained using concentrations from ground stations on both Korean and Chinese sides and from shipboard and aircraft measurements. Wet deposition fluxes were determined at ground stations on the Korean side. The dry deposition flux over the Yellow Sea was much greater than those for other world oceans. As a whole, the amounts of wet depositions of nitrogen and sulfur were 1.9 and 1.5 times larger than the amounts of respective dry depositions. Substantial influence from China caused by high emissions in East China and westerly wind was possibly suggested. However, the influence from nitrogen emission in Korea was also confirmed.
显示更多 [+] 显示较少 [-]Microbial Metabolic Potential Affected by Surplus Wastewater Irrigation in Tropical Soil Cultivated with Tifton 85 Bermuda Grass (Cynodon dactylon Pers. X C. niemfuensis Vanderyst)
2010
de Paula, A. M. | da Fonseca, A. F. | Cardoso, E. J. B. N. | Melfi, A. J.
Agricultural reuse of treated sewage effluent (TSE) is an environmental and economic practice; however, little is known about its effects on the characteristics and microbial function in tropical soils. The effect of surplus irrigation of a pasture with TSE, in a period of 18 months, was investigated, considering the effect of 0% surplus irrigation with TSE as a control. In addition, the experiment consisted of three surplus treatments (25%, 50%, and 100% excess) and a nonirrigated pasture area (SE) to compare the soil microbial community level physiological profiles, using the Biolog method. The TSE application increased the average substrate consumption of the soil microbial community, based on the kinetic parameters of the average well color development curve fitting. There were no significant differences between the levels of surplus irrigation treatments. Surplus TSE pasture irrigation caused minor increases in the physiological status of the soil microbial community but no detectable damage to the pasture or soil.
显示更多 [+] 显示较少 [-]Ecological Restoration of Polluted Plain Rivers Within the Haihe River Basin in China
2010
Wang, W. | Tang, X. Q. | Huang, S. L. | Zhang, S. H. | Lin, C. | Liu, D. W. | Che, H. J. | Yang, Q. | Scholz, Miklas
The Haihe River basin is located in the north of China and has an area of 318,000 km². The region is politically important and economically advanced. For example, the Haihe River basin sustains a population of more than 120 million and generates a gross domestic production of approximately 2,600 billion Chinese Yuan. The ecological health of plain rivers within the Haihe River basin of China is questionable because of severe water shortages, considerable water, soil and air pollution, and the destruction of the natural river morphologies. It is therefore necessary to establish a generic and theoretical restoration methodology to guide river ecological restoration efforts in the future. Thirteen methodologies and technologies were selected from an existing suit of ecosystem restoration techniques currently applied to the Haihe River catchment. These technologies were further divided into three types: water quantity adjustment, water purification, and habitat improvement. The most suitable ecological restoration techniques were selected as a function of all three types. However, direct methods of addressing water quantity and quality problems were identified as critical for the success of future restoration efforts. Examples of the application of the conceptual ecological restoration model for the representative plain rivers Beiyunhe, Yongding and Wei, all located within the Haihe River Basin, are also assessed. The conceptual model provides practical solutions to pollution problems, is generic in nature, and could therefore be applied to other polluted watercourses in densely populated regions in the developed and developing world.
显示更多 [+] 显示较少 [-]Copper Biosorption by Biomass of Marine Alga: Study of Equilibrium and Kinetics in Batch System and Adsorption/Desorption Cycles in Fixed Bed Column
2010
Fagundes-Klen, Márcia Regina | Veit, Márcia Teresinha | Borba, Carlos Eduardo | Bergamasco, Rosângela | de Lima Vaz, Luiz Gustavo | da Silva, Edson Antonio
Copper biosorption onto chemically modified biomass of marine alga Sargassum filipendula was investigated in a batch reactor and a fixed bed column. Experiments were carried out in the batch reactor to obtain kinetic and equilibrium data and to assess the copper desorption efficiency of different eluent solutions. The pseudo-first-order, pseudo-second-order, and Langmuir kinetic models were used to correlate kinetic data. The experimental data fitted well to the pseudo first order and Langmuir kinetic models. Langmuir and Freundlich models were applied to describe the equilibrium data obtained at a fixed temperature of 30°C and at pH values of 3.0, 4.0, 5.0, and 6.0. The maximum capacities of copper biosorption onto the algal biomass were 1.43, 1.59, 2.40, and 2.36 mequiv./g at pH 3.0, 4.0, 5.0, and 6.0, respectively. The efficiencies of two eluent solutions (calcium chloride and hydrochloric acid) for copper removal from the biomass were evaluated at different concentrations (0.1, 0.2, 0.5, and 1.0 mol/L). The efficiencies of the calcium chloride solutions varied from 1% to 14%, while efficiencies varying from 95% to 99% were obtained when hydrochloric acid solutions were applied. Three adsorption/desorption cycles were carried out in a fixed bed column using 0.1 mol/L hydrochloric acid as eluent solution. The results showed that an increase in the number of cycles led to a reduction in the adsorption capacity of the alga. The desorbed copper fraction presented no significant variation, remaining around 63% in the three adsorption/desorption cycles.
显示更多 [+] 显示较少 [-]TiO₂-Assisted Photodegradation of Direct Blue 78 in Aqueous Solution in Sunlight
2010
Song, Ya-Li | Li, Ji-Tai | Bai, Bo
The photodegradation of azo dyes aqueous solution has been investigated using TiO₂ as catalyst in sunlight. The effect of amount of catalyst, concentration of dye, and pH value on the degradation of Direct Blue 78 was observed. A complete degradation of 100 mg/L Direct Blue 78 solution under solar irradiation was achieved in 6 h at pH 3.0, dosage of TiO₂ 1.0 g/L. A possible pathway for the photodegradation of Direct Blue 78 in sunlight was proposed.
显示更多 [+] 显示较少 [-]Heavy Metal Contents and Distribution in Coastal Sediments of the Gulf of Trieste (Northern Adriatic Sea, Italy)
2010
Acquavita, Alessandro | Predonzani, Sergio | Mattassi, Giorgio | Rossin, Pietro | Tamberlich, Francesco | Falomo, Jari | Valic, Iztok
A set of ten heavy metals (Al, As, Cd, Cr, Cu, Hg, Ni, Pb, V, and Zn) was investigated in surface sediments (0-5 cm) collected in 21 sites of the Gulf of Trieste, Northern Adriatic Sea (Italy). The aim of this work was to obtain a preliminary assessment about the levels and spatial distribution of these selected elements. Ancillary parameters such as grain size, total organic carbon, and total nitrogen were also determined. The enrichment factor was calculated to discriminate if a natural condition or a status of anthropogenic contamination occurs. In addition, a set of sediment quality guidelines, mean effect low range and effect medium range quotients, was also applied in order to predict the probability of adverse biological effects on the benthic community.
显示更多 [+] 显示较少 [-]Nutrient Fluxes in Planted Norway Spruce Stands of Different Age in Southern Poland
2010
Małek, Stanisław
The fluxes of N-NO ₃ ⁻ , N-NH ₄ ⁺ , S-SO ₄ ²⁻ , Na⁺, K⁺, Ca²⁺ and Mg²⁺ from bulk precipitation to throughfall, stemflow and soil water surface flows were studied during 1999-2003 in planted Norway spruce forest stands of different ages (11, 24, 91 and 116 years in 1999). Also, runoff from the corresponding Potok Dupniański Catchment in the Silesian Beskid Mts was studied. N deposition was above the critical load for coniferous trees. The interception increased with stand age as well as leaf area index and so did the leaching from the canopy of almost all the analysed elements, but especially S-SO ₄ ²⁻ , H⁺ and K⁺. The nutrient fluxes varied with age of the spruce stands. Throughfall showed a high amount of S and of the strong acids (S-SO ₄ ²⁻ and N-NO ₃ ⁻ ) deposited to the soil, especially in older spruce age classes. Decomposition of organic matter caused a rise in water acidity and an increase in the concentrations of all the analysed ions; the leaching of minerals, however, was low (under 1%). The horizontal soil water flow showed an increase in the amount of water and amount of ions and contributed to a further decrease of pH at the soil depth of 20 cm. Element concentrations and their amounts increased with water penetrating vertically and horizontally on the slopes. Considerable amounts of ions, especially S and alkaline cations, were carried beyond the reach of the root system and then left the catchment. In the long term, these mineral losses will adversely affect health and growth of the spruce stands, and the increased acidity with stand age will presumably have negative effects on the runoff water ecosystem.
显示更多 [+] 显示较少 [-]Historical Changes in Levels of Organic Pollutants in Sediment Cores from Brno Reservoir, Czech Republic
2010
Franců, E. | Schwarzbauer, J. | Lána, R. | Nývlt, D. | Nehyba, S.
Results of a comprehensive study are presented on the spatial and depth-related distribution of persistent organic pollutants (POPs) in sediments of the Brno reservoir, Czech Republic. Based on sedimentological observations, three major historic phases were identified related to the evolution of the depositional environment, flow rate, and material input. Data on organic carbon, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides showed specific distribution patterns in a 3-m-deep core. The analysis of the depth trends of the geochemical data combined with sedimentology made it possible to distinguish between remote sources of the pollutants, early weathering alterations of POPs, transport by river associated with organic matter as sorbent on one hand, and local sources weakly related to lithology on the other hand. The integrated sedimentological and environmental geochemical archive provided an improved dynamic view of the pollution in historical terms.
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