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741.
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
742.
Adaptive capacity determinants in developed states: examples from the Nordic countries and Russia 总被引:1,自引:1,他引:0
E. Carina H. Keskitalo Halvor Dannevig Grete K. Hovelsrud Jennifer J. West Åsa Gerger Swartling 《Regional Environmental Change》2011,11(3):579-592
Adaptive capacity in a community context has so far mainly been studied in developing countries as well as indigenous communities
in the industrialised world. This article adds to that literature through reviewing studies undertaken in the Nordic countries
and Russia, highlighting the ways in which general determinants of adaptive capacity play out in Northern, industrialised
contexts. The paper illustrates that the determinants of adaptive capacity in industrialised states exhibit systematic differences
from mixed subsistence-cash based communities such as those found in Arctic Canada. We discuss in particular the importance
of economic resources in a market-based system, technological competition, and infrastructure, in determining adaptive capacity
of natural resource-dependent communities in the Nordic countries and Russia. The paper also illustrates differences in adaptive
capacity within the case study region, including between peripheral and central locations with regard to economic resources
and diversification possibilities, and between Nordic and Russian cases with regard to infrastructure and technology access.
The findings indicate that understanding of determinants of adaptive capacity in resource-dependent communities would benefit
from both further contextualisation and broad comparison, across different types of political and administrative systems. 相似文献
743.
Meghann E. Jarchow Justin W. Rice Rebekah M. Ritson Sarah K. Hargreaves 《Sustainability Science》2011,6(2):253-254
Conference organizers are increasingly making efforts to reduce resource use at conferences, yet few responsibilities are
placed on attendees. We hosted an ecology conference and offered attendees a discount if they took a sustainability pledge
agreeing to reduce their resource use at the conference. In a post-conference survey, 83% of respondents reported fulfilling
the pledge, but 62% indicated that convenience was the biggest obstacle impeding their ability to continue the pledge during
and after the conference. We found great willingness by attendees to reduce resource use at and beyond our conference, and
facilitating their participation was an important part of our success. 相似文献
744.
Long-term (1860–2010) catchment mass balance calculations rely on models and assumptions which are sources of uncertainty
in acidification assessments. In this article, we report on an application of MAGIC to model acidification at the four Swedish
IM forested catchments that have been subject to differing degrees of acidification stress. Uncertainties in the modeled mass
balances were mainly associated with the deposition scenario and assumptions about sulfate adsorption and soil mass. Estimated
base cation (BC) release rates (weathering) varied in a relatively narrow range of 47–62 or 42–47 meq m−2 year−1, depending on assumptions made about soil cation exchange capacity and base saturation. By varying aluminum solubility or
introducing a dynamic weathering feedback that allowed BC release to increase at more acidic pHs, a systematic effect on predicted
changes in acid neutralizing capacity (ΔANC ca. 10–41 μeq l−1) and pH (ca. ΔpH = 0.1–0.6) at all sites was observed. More robust projections of future changes in pH and ANC are dependent
on reducing uncertainties in BC release rates, the timing, and extent of natural acidification through BC uptake by plants,
temporal changes in soil element pools, and fluxes of Al between compartments. 相似文献
745.
The chemical composition of the odors typical of fires has recently been deciphered. Basically the constituents are mixtures of acetophenone, benzyl alcohol, hydroxylated derivatives of benzaldehyde, methoxylated and/or alkylated phenols and naphthalene. This finding makes it possible to develop objective, practical analytic measurement methods for the burnt smell as a contribution to improving fire damage assessment and remediation monitoring. With the aid of an artificially produced burnt smell and a panel of testers the odor detection threshold of a test mixture was determined olfactometrically to 2 μg m−3. Using a defined burnt-smell atmosphere in a test chamber, analytical methods with active sampling, the adsorbents XAD 7 and TENAX TA, and GC/MS measurement were then optimized and tested with a view to being able to carry out sensitive quantitative measurement of burnt smells. A further practical method with particular application to the qualitative characterization of this odor is based on the use of a new SPME (solid-phase microextraction) field sampler with DVB/CAR/PDMS (divinylbenzene/Carboxen™/polydimethylsiloxane) fibers. 相似文献
746.
Indiscriminate use of agrochemicals worldwide, particularly, persistent organic pollutants (POPs), is of concern. Endosulfan, a POP, is used by various developing/developed nations and is known to adversely affect the development and the hormonal profiles of humans and animals. However, little is known about the molecular players/pathways underlying the adverse effects of endosulfan. We therefore analyzed the global gene expression changes and subsequent adverse effects of endosulfan using Drosophila. We used Drosophila melanogaster keeping in view of its well annotated genome and the wealth of genetic/molecular reagents available for this model organism. We exposed third instar larvae of D. melanogaster to endosulfan (2.0 μg mL−1) for 24 h and using microarray, we identified differential expression of 256 genes in exposed organisms compared to controls. These genes are associated with cellular processes such as development, stress and immune response and metabolism. Microarray results were validated through quantitative PCR and biochemical assay on a subset of genes/proteins. Taking cues from microarray data, we analyzed the effect of endosulfan on development, emergence and survival of the organism. In exposed organisms, we observed deformities in hind-legs, reminiscent of those observed in higher organisms exposed to endosulfan. In addition, we observed delayed and/or reduced emergence in exposed organisms when compared to their respective controls. Together, our studies not only highlight the adverse effects of endosulfan on the organism but also provide an insight into the possible genetic perturbations underlying these effects, which might have potential implications to higher organisms. 相似文献
747.
Information on carry-over of contaminants from feed to animal food products is essential for appropriate human risk assessment of feed contaminants. The carry-over of potentially hazardous persistent organic pollutants (POPs) from feed to fillet was assessed in consumption sized Atlantic salmon (Salmo salar). Relative carry-over (defined as the fraction of a certain dietary POP retained in the fillet) was assessed in a controlled feeding trial, which provided fillet retention of dietary organochlorine pesticides (OCPs), dioxins (PCDD/Fs), polychlorinated biphenyls (PCBs), and brominated flame retardants (BFRs). Highest retention was found for OCPs, BFRs and PCBs (31-58%), and the lowest retentions were observed for PCDD/Fs congeners (10-34%). National monitoring data on commercial fish feed and farmed Atlantic salmon on the Norwegian market were used to provide commercially relevant feed-to-fillet transfer factors (calculated as fillet POP level divided by feed POP level), which ranged from 0.4 to 0.5, which is a factor 5-10 times higher than reported for terrestrial meat products. For the OCP with one of the highest relative carry-over, toxaphene, uptake and elimination kinetics were established. Model simulations that are based on the uptake and elimination kinetics gave predicted levels that were in agreement with the measured values. Application of the model to the current EU upper limit for toxaphene in feed (50 μg kg−1) gave maximum fillet levels of 22 μg kg−1, which exceeds the estimated permissible level (21 μg kg−1) for toxaphene in fish food samples in Norway. 相似文献
748.
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
749.
Stone JJ Dreis EK Lupo CD Clay SA 《Journal of environmental science and health. Part. B》2011,46(8):752-762
The land application of aged chortetracycle (CTC) and tylosin-containing swine manure was investigated to determine associated impacts to soil microbial respiration, nutrient (phosphorus, ammonium, nitrate) cycling, and soil microbial community structure under laboratory conditions. Two silty clay loam soils common to southeastern South Dakota were used. Aerobic soil respiration results using batch reactors containing a soil-manure mixture showed that interactions between soil, native soil microbial populations, and antimicrobials influenced CO(2) generation. The aged tylosin treatment resulted in the greatest degree of CO(2) inhibition, while the aged CTC treatment was similar to the no-antimicrobial treatment. For soil columns in which manure was applied at a one-time agronomic loading rate, there was no significant difference in soil-P behavior between either aged CTC or tylosin and the no-antimicrobial treatment. For soil-nitrogen (ammonium and nitrate), the aged CTC treatment resulted in rapid ammonium accumulation at the deeper 40cm soil column depth, while nitrate production was minimal. The aged CTC treatment microbial community structure was different than the no-antimicrobial treatment, where amines/amide and carbohydrate chemical guilds utilization profile were low. The aged tylosin treatment also resulted in ammonium accumulation at 40 cm column depth, however nitrate accumulation also occurred concurrently at 10 cm. The microbial community structure for the aged tylosin was also significantly different than the no-antimicrobial treatment, with a higher degree of amines/amides and carbohydrate chemical guild utilization compared to the no-antimicrobial treatment. Study results suggest that land application of CTC and tylosin-containing manure appears to fundamentally change microbial-mediated nitrogen behavior within soil A horizons. 相似文献
750.
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