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641.
Nomiyama K Eguchi A Mizukawa H Ochiai M Murata S Someya M Isobe T Yamada TK Tanabe S 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3364-3373
We determined the residue levels and patterns of hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and related compounds, such as PBDEs, methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in the blood of eleven cetacean species stranded along the Japanese coasts. The dominant OH- and MeO-PBDE isomers found in all cetaceans were 6OH-BDE47 and 6MeO-BDE47. Additionally, 2,4,6-triBPh was dominant isomer in all cetaceans. In contrast, specific differences in the distribution of para- and meta- OH-PBDE isomers and some BPhs (potential PBDEs metabolites) were found among the cetaceans.Residue levels of ΣMeO-PBDEs and 6OH-BDE47 + 2′OH-BDE68, and 2,4,6-triBPh and 6OH-BDE47 + 2′OH-BDE68 showed a significant positive correlation. These results may suggest that the large percentages of OH-PBDEs, MeO-PBDEs and 2,4,6-triBPh might share common source (i.e. biosynthesis by marine organisms), or metabolic pathway in cetacean species. Significant correlations were found between the concentrations of BDE99 and 2,4,5-triBPh. This result suggested that 2,4,5-triBPh in cetaceans could be a metabolite of BDE99. 相似文献
642.
Matilda Palm Madelene Ostwald Indu K. Murthy Rajiv K. Chaturvedi N. H. Ravindranath 《Regional Environmental Change》2011,11(2):423-435
This paper analyses environmental and socio-economic barriers for plantation activities on local and regional level and investigates
the potential for carbon finance to stimulate the increased rates of forest plantation on wasteland, i.e., degraded lands,
in southern India. Building on multidisciplinary field work and results from the model GCOMAP, the aim is to (1) identify
and characterize the barriers to plantation activities in four agro-ecological zones in the state of Karnataka and (2) investigate
what would be required to overcome these barriers and enhance the plantation rate and productivity. The results show that
a rehabilitation of the wasteland based on plantation activities is not only possible but also anticipated by the local population
and would lead to positive environmental and socio-economic effects at a local level. However, in many cases, the establishment
of plantation activities is hindered by a lack of financial resources, low land productivity and water scarcity. Based on
the model used and the results from the field work, it can be concluded that certified emission reductions such as carbon
credits or other compensatory systems may help to overcome the financial barrier; however, the price needs to be significantly
increased if these measures are to have any large-scale impact. 相似文献
643.
Stakeholder engagement in social learning to resolve controversies over land-use change to plantation forestry 总被引:1,自引:1,他引:0
Rapid land-use change arising from incentives for afforestation has created tensions in rural communities previously dominated
by agricultural enterprises. This paper reports on an innovative experiment with social learning that incorporated participatory
modelling to resolve community concerns in a case study of plantation forestry in the Upper Clarence catchment of north-eastern
NSW Australia. The development of a diagnostic framework helped identify socioeconomic and environmental issues within the
community for investigation by a self-selected participatory advisory committee (PAC) representing a diversity of views. Implementation
of a social learning exercise offered empathetic and intellectual engagement among PAC members that maintained interest, built
confidence, and improved problem-solving capacity while fostering group ownership over decision making. A shared understanding
of dynamic landscape problems helped empower participants to collaboratively develop solutions for improved management and
operational practices, and cooperate to explore further options for plantation industry development under existing policy
guidelines which are presented in this paper. As a result of frank discussions between diverse stakeholders in a mutually
respectful learning environment that combined local, scientific and expert knowledge, concerns dissipated and participants
developed a more favourable view of plantation forestry activity. 相似文献
644.
The present study focused on early responses of land snails Eobania vermiculata to organic environmental contaminants, by investigating the use of a newly-established method for the measurement of protein carbonylation as a new biomarker of terrestrial pollution, as well as by measuring the ROS production and the DNA damage. Land snails were exposed to different concentrations of chlorpyrifos, parathion-methyl or PAHs in vivo or in vitro in the laboratory. The susceptibility of exposed snails was increased in relation to oxidative stress induced by contaminants tested. A statistically significant increase in ROS production, protein carbonylation and DNA damage was revealed in the snails treated with pollutants, compared to the untreated ones. The results indicated the effectiveness of measuring ROS production and DNA damage and reinforce the application of the present ELISA method in organic terrestrial pollution biomonitoring studies. 相似文献
645.
Mobility of Cd and Cu in formulated sediments coated with iron hydroxides and/or humic acids: a DGT and DGT-PROFS modeling approach 总被引:1,自引:0,他引:1
The diffusive gradients technique in thin films (DGT) was used to investigate the kinetic resupply of Cd and Cu to pore water from the solid phase. For the sake of simplification, experiments were performed using formulated sediments that differed in the presence or absence of humic acids (HA) and/or of iron hydroxides (i.e., goethite and ferrihydrite). The effects of the time after the contamination of the solid phase (aging effect) on formulated sediments that were coated with goethite and HA and spiked with Cd were also evaluated. Kinetic DGT results were interpreted using the newly developed, multi-compartmental model DGT-PROFS.Due to Cu humate formation, the addition of HA slightly increased the Cu concentration in the pore water independent of the effect of the iron hydroxide coating on the formulated sediments and slightly decreased that of Cd. The impact of 8-190 d of aging resulted in a significant decrease in the Cd concentration of the pore water over an increasing incubation time.Modeling our results with DGT-PROFS led to the following conclusions concerning the impact of HA and iron hydroxides on Cd and Cu availability. First, in the presence of HA and absence of iron hydroxides, Cd is associated mainly with weak sites, while Cu is bound to strong sites. Similarly, in the presence of both iron hydroxides and HA, Cu appeared to be more heavily associated with the strong sites than did Cd. When the incubation time increased from 8 to 190 d, a proportion of Cd initially adsorbed onto weak sites transferred to the strong sites, suggesting that the adsorption of Cd on sediments is controlled partially by slow kinetic processes. 相似文献
646.
Opel O Palm WU Steffen D Ruck WK 《Environmental pollution (Barking, Essex : 1987)》2011,159(4):924-931
Comparability of sediment analyses for semivolatile organic substances is still low. Neither screening of the sediments nor organic-carbon based normalization is sufficient to obtain comparable results. We are showing the interdependency of grain-size effects with inside-sediment organic-matter distribution for PAH, PCB and organochlorine compounds. Surface sediment samples collected by Van-Veen grab were sieved and analyzed for 16 PAH, 6 PCB and 18 organochlorine pesticides (OCP) as well as organic-matter content. Since bulk concentrations are influenced by grain-size effects themselves, we used a novel normalization method based on the sum of concentrations in the separate grain-size fractions of the sediments. By calculating relative normalized concentrations, it was possible to clearly show underlying mechanisms throughout a heterogeneous set of samples. Furthermore, we were able to show that, for comparability, screening at <125 μm is best suited and can be further improved by additional organic-carbon normalization. 相似文献
647.
N deposition as a threat to the World's protected areas under the Convention on Biological Diversity
Bleeker A Hicks WK Dentener F Galloway J Erisman JW 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2280-2288
This paper combines the world’s protected areas (PAs) under the Convention on Biological Diversity (CBD), common classification systems of ecosystem conservation status, and current knowledge on ecosystem responses to nitrogen (N) deposition to determine areas most at risk. The results show that 40% (approx. 11% of total area) of PAs currently receive >10 kg N/ha/yr with projections for 2030 indicating that this situation is not expected to change. Furthermore, 950 PAs are projected to receive >30 kg N/ha/yr by 2030 (approx. twice the 2000 number), of which 62 (approx. 11,300 km2) are also Biodiversity Hotspots and G200 ecoregions; with forest and grassland ecosystems in Asia particularly at risk. Many of these sites are known to be sensitive to N deposition effects, both in terms of biodiversity changes and ecosystem services they provide. Urgent assessment of high risk areas identified in this study is recommended to inform the conservation efforts of the CBD. 相似文献
648.
Andersen JK Boldrin A Christensen TH Scheutz C 《Waste management (New York, N.Y.)》2011,31(9-10):1934-1942
A comprehensive experimental setup with six single-family home composting units was monitored during 1 year. The composting units were fed with 2.6-3.5 kg organic household waste (OHW) per unit per week. All relevant consumptions and emissions of environmental relevance were addressed and a full life-cycle inventory (LCI) was established for the six home composting units. No water, electricity or fuel was used during composting, so the major environmental burdens were gaseous emissions to air and emissions via leachate. The loss of carbon (C) during composting was 63-77% in the six composting units. The carbon dioxide (CO(2)) and methane (CH(4)) emissions made up 51-95% and 0.3-3.9% respectively of the lost C. The total loss of nitrogen (N) during composting was 51-68% and the nitrous oxide (N(2)O) made up 2.8-6.3% of this loss. The NH(3) losses were very uncertain but small. The amount of leachate was 130 L Mg(-1) wet waste (ww) and the composition was similar to other leachate compositions from home composting (and centralised composting) reported in literature. The loss of heavy metals via leachate was negligible and the loss of C and N via leachate was very low (0.3-0.6% of the total loss of C and 1.3-3.0% of the total emitted N). Also the compost composition was within the typical ranges reported previously for home composting. The level of heavy metals in the compost produced was below all threshold values and the compost was thus suitable for use in private gardens. 相似文献
649.
N. Mithil Kumar K. Varaprasad G. Ramachandra Reddy G. Siva Mohan Reddy Y. Sivabharathi G. Venkata Subba Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):225-229
Synthesis and characterization of novel biodegradable, water soluble and optically active DL-malic acid (DMA) and citric acid
(CA) copolymers were studied for possible use as antibacterial agents. The copolymers were synthesized by direct bulk melt
condensation in the absence of a catalyst above 150 °C. Characterization of obtained copolymers was carried out with the help
of infrared absorption spectra, differential scanning calorimetry and thermo gravimetric analysis. The antibacterial activity
of copolymers against bacteria was investigated. The results obtained shows the above copolymers possess a broad wound dressing
activity against different types of bacteria and may be useful as antibacterial agents. 相似文献
650.
Poly-β-hydroxybuyrate (PHB) is a carbon—energy storage material which is accumulated as intracellular granule in variety of
microorganism under nutrient starved conditions. Solid PHB is a biodegradable thermoplastic polymer and is utilizable in various
ways similar to many conventional plastics. Ralstonia eutropha (Alcaligenes sp.), a gram negative bacteria accumulates PHB as insoluble granules inside the cells when nutrients other than carbon are
limited. In this report effort has been made to analyze PHB granule synthesis inside Alcaligenes sp. NCIM 5085 by transmission electron microscopy and qualitative estimation of PHB was carried out by fourier transform
infrared spectroscopy which provide better precision compared to other conventional techniques previously applied for PHB
determination. Maximum PHB concentration of 2.20 ± 0.40 g/L and cell biomass of 3.42 ± 0.20 g/L was obtained after 48.0 h
of fermentation. Leudking-Piret equation deduced mixed growth associated product formation which varies from earlier reports. 相似文献