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881.
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
882.
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
883.
884.
Amado LL Rosa CE Castro MR Votto AP Santos LC Marins LF Trindade GS Fraga DS Damé RC Barros DM Geracitano LA Bianchini A de la Torre FR Monserrat JM 《Chemosphere》2011,82(11):1563-1570
This study analyzed water quality in regions around Patos lagoon (Southern Brazil) that are under anthropogenic pressure. Water samples were collected from five different sites, including one used as a source for human consumption (COR) and others known to be influenced by human activities (IP). Danio rerio (Teleostei, Cyprinidae) organisms were exposed for 24 h to these water samples, plus a control group. It was observed that: (1) reactive oxygen species levels were lower in COR and IP than in the control group; (2) glutamate-cysteine ligase (catalytic subunit) expression was higher in COR than in other sites; (3) exposure to all water samples affected long-term memory (LTM) when compared to control group. Thus, some water samples possess the ability to modulate the antioxidant system and to induce a decline in cognitive functions, as measured by LTM. The obtained results indicate that a combination of variables of different organization level (molecular, biochemical and behavioral) can be employed to analyze water quality in impacted regions. 相似文献
885.
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
886.
Ochoa-Hueso R Allen EB Branquinho C Cruz C Dias T Fenn ME Manrique E Pérez-Corona ME Sheppard LJ Stock WD 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2265-2279
We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. 相似文献
887.
Kuo LJ Louchouarn P Herbert BE Brandenberger JM Wade TL Crecelius E 《Environmental pollution (Barking, Essex : 1987)》2011,159(4):983-990
Reconstructions of 250 years historical inputs of two distinct types of black carbon (soot/graphitic black carbon (GBC) and char-BC) were conducted on sediment cores from two basins of the Puget Sound, WA. Signatures of polycyclic aromatic hydrocarbons (PAHs) were also used to support the historical reconstructions of BC to this system. Down-core maxima in GBC and combustion-derived PAHs occurred in the 1940s in the cores from the Puget Sound Main Basin, whereas in Hood Canal such peak was observed in the 1970s, showing basin-specific differences in inputs of combustion byproducts. This system showed relatively higher inputs from softwood combustion than the northeastern U.S. The historical variations in char-BC concentrations were consistent with shifts in climate indices, suggesting an influence of climate oscillations on wildfire events. Environmental loading of combustion byproducts thus appears as a complex function of urbanization, fuel usage, combustion technology, environmental policies, and climate conditions. 相似文献
888.
Müller CE Gerecke AC Alder AC Scheringer M Hungerbühler K 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1419-1426
Anthropogenic perfluorinated compounds (PFCs), especially the perfluoroalkyl acids (PFAAs) are ubiquitously found in surface waters around the globe. Emissions from households, industries and also atmospheric transport/deposition are discussed as the possible sources. In this study, these sources are evaluated using Switzerland as the study area. Forty-four surface water locations in different rivers and an Alpine lake were investigated for 14 PFAAs, four precursors and acesulfame, an artificial sweetener used as a population marker. Concentrations of individual PFAAs were generally low, between 0.02 and 10 ng/L. Correlation analysis showed that some PFAAs concentrations correlated well with population and less with catchment area, indicating that emissions from population, i.e., from consumer products, is the most important source to surface waters in Switzerland. The correlation with the population marker acesulfame confirmed this observation but highlighted also a few elevated PFAA levels, some of which could be attributed to industrial emissions. 相似文献
889.
It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations. 相似文献
890.
Otones V Álvarez-Ayuso E García-Sánchez A Santa Regina I Murciego A 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2637-2647
A mining area affected by the abandoned exploitation of an arsenical tungsten deposit was studied in order to assess its arsenic pollution level and the feasibility of native plants for being used in phytoremediation approaches. Soil and plant samples were collected at different distances from the polluting sources and analysed for their As content and distribution. Critical soil total concentrations of As were found, with values in the range 70-5330 mg kg−1 in the uppermost layer. The plant community develops As tolerance by exclusion strategies. Of the plant species growing in the most polluted site, the shrubs Salix atrocinerea Brot. and Genista scorpius (L.) DC. exhibit the lowest bioaccumulation factor (BF) values for their aerial parts, suggesting their suitability to be used with revegetation purposes. The species Scirpus holoschoenus L. highlights for its important potential to stabilise As at root level, accumulating As contents up to 3164 mg kg−1. 相似文献