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21.
In this paper, the policy of nature conservation in Norway is analysed, with a particular focus on policy development during the last decade moving in the direction of multi-level governance. It is argued that the logic of policy making has shifted from what can be described as 'the politics of expertise' to a process of 'politicisation'. A process of politicisation can be observed both in terms of the nature of arguments being used, and in terms of who the dominant actors are. The subjects of analysis are issues taken up by the political parties in the Parliament, and the paper focuses on two controversial questions. One is about the localisation of conservation areas on private land and the state's liability for compensation. The other is the question of whether the management of conservation areas, and in particular national parks, should be under the control of local government or the state environmental bureaucracy. The analysis documents a process moving in the direction of more complex governance structure involving more actors and broader local participation challenging the role of the professional bureaucracy.  相似文献   
22.
The thermal destruction of benzene in methane/air flue gas is studied experimentally using an atmospheric laminar flow reactor in laboratory scale. The reactor is operated at four different fuel equivalent ratios (phi = 0.06, 0.1,0.5, 3.7), and temperatures in the range from 850 to 973 K and realises a residence time of 5 s. Stable-species concentrations are measured by gas chromatography (GC) and high-pressure liquid chromatography (HPLC), where phenol, acetylene, formaldehyde, acrolein, methane and acetaldehyde are the major hydrocarbon products besides CO and CO2. The augmentation of the temperature from 850 to 973 K increases the benzene conversion rate from 55% to 99%. The experimental results for one fuel equivalent ratio (phi = 0.5) are compared to the benzene model proposed by Emdee et al. (J. Phys. Chem. 92 (1992) 2151-2161). A fair agreement is observed for the benzene consumption and the CO production throughout the temperature range considered here. The small hydrocarbons are not very well matched, which requires further research on the sub-models. Our experimental results on laboratory scale provide a database for the modelling of benzene oxidation in waste incinerators.  相似文献   
23.
Differences in stress tolerance and reproductive traits may drive the competitive hierarchy between non-indigenous and indigenous species and turn the former ones into successful invaders. In the northern Baltic Sea, the non-indigenous Gammarus tigrinus is a recent invader of littoral ecosystems and now occupies comparable ecological niches as the indigenous G. zaddachi. In laboratory experiments on specimens collected between June and August 2009 around Tvärminne in southern Finland (59°50′N/23°15′E), the tolerances towards heat stress and hypoxia were determined for the two species using lethal time, LT50, as response variable. The brood size of the two species was also studied and some observations were made on maturation of juveniles. Gammarus tigrinus was more resistant to hypoxia and survived at higher temperatures than G. zaddachi. Brood size was also greater in G. tigrinus than in G. zaddachi and G. tigrinus matured at a smaller size and earlier than G. zaddachi. Hence, there are clear competitive advantages for the non-indigenous G. tigrinus compared to the indigenous G. zaddachi, and these may be further strengthened through ongoing environmental changes related to increased eutrophication and a warming climate in the Baltic Sea region.  相似文献   
24.
We investigated the impacts of warming and elevated pCO2 on newly settled Amphibalanus improvisus from Kiel Fjord, an estuarine ecosystem characterized by significant natural pCO2 variability. In two experiments, juvenile barnacles were maintained at two temperature and three pCO2 levels (20/24 °C, 700–2,140 μatm) for 8 weeks in a batch culture and at four pCO2 levels (20 °C, 620–2,870 μatm) for 12 weeks in a water flow-through system. Warming as well as elevated pCO2 hardly affected growth or the condition index of barnacles, although some factor combinations led to temporal significances in enhanced or reduced growth with an increase in pCO2. While warming increased the shell strength of A. improvisus individuals, elevated pCO2 had only weak effects. We demonstrate a strong tolerance of juvenile A. improvisus to mean acidification levels of about 1,000 μatm pCO2 as is already naturally experienced by the investigated barnacle population.  相似文献   
25.
Weather, climate, and flood predictions are incorporated into human decisions in a wide variety of situations, including decisions related to hazardous hydrometeorological events. This article examines ethical aspects of such predictions and decisions, focusing on the case of the 1997 Red River flood in Grand Forks, North Dakota and East Grand Forks, Minnesota (US). The analysis employs a formal ethical framework and analytical method derived from medical and business ethics. The results of the analysis highlight issues related to forecast generation, communication of forecast meaning and uncertainty, responsibility for the use of forecasts in decision making, and trade-offs between the desire for forecast certainty and the risk of missed events. Implications of the analysis for the broader arenas of weather, climate, and flood prediction and disaster management are also discussed.  相似文献   
26.
The fate of key species, such as the barnacle Amphibalanus improvisus, in the course of global change is of particular interest since any change in their abundance and/or performance may entail community-wide effects. In the fluctuating Western Baltic, species typically experience a broad range of environmental conditions, which may preselect them to better cope with climate change. In this study, we examined the sensitivity of two crucial ontogenetic phases (naupliar, cypris) of the barnacle toward a range of temperature (12, 20, and 28°C) and salinity (5, 15, and 30 psu) combinations. Under all salinity treatments, nauplii developed faster at intermediate and high temperatures. Cyprid metamorphosis success, in contrast, was interactively impacted by temperature and salinity. Survival of nauplii decreased with increasing salinity under all temperature treatments. Highest settlement rates occurred at the intermediate temperature and salinity combination, i.e., 20°C and 15 psu. Settlement success of “naive” cyprids, i.e., when nauplii were raised in the absence of stress (20°C/15 psu), was less impacted by stressful temperature/salinity combinations than that of cyprids with a stress history. Here, settlement success was highest at 30 psu particularly at low and high temperatures. Surprisingly, larval survival was not highest under the conditions typical for the Kiel Fjord at the season of peak settlement (20°C/15 psu). The proportion of nauplii that ultimately transformed to attached juveniles was, however, highest under these “home” conditions. Overall, only particularly stressful combinations of temperature and salinity substantially reduced larval performance and development. Given more time for adaptation, the relatively smooth climate shifts predicted will probably not dramatically affect this species.  相似文献   
27.
The aims were to assess the impact of a total smoking ban on the level of airborne contaminants and the urinary cotinine levels in the employees in bars and restaurants. In a follow up design, 13 bars and restaurants were visited before and after the implementation of a smoking ban. Ninety-three employees in the establishments were initially included into the study. The arithmetic mean concentration of nicotine and total dust declined from 28.3 microg m(-3) (range, 0.4-88.0) and 262 microg m(-3) (range, 52-662), respectively, to 0.6 microg m(-3) (range, not detected-3.7) and 77 microg m(-3) (range, not detected-261) after the smoking ban. The Pearson correlation coefficient between airborne nicotine and total dust was 0.86 (p < 0.001; n = 48). The post-shift geometric mean urinary cotinine concentration declined from 9.5 microg g(-1) creatinine (cr) (95% CI 6.5-13.7) to 1.4 microg g(-1) cr (95% CI 0.8-2.5) after the ban (p < 0.001) in 25 non-snuffing non-smokers. A reduction from 1444 microg g(-1) cr (95% CI 957-2180) to 688 microg g(-1) cr (95% CI 324-1458) was found (p < 0.05) in 29 non-snuffing smokers. The urinary cotinine levels increased from 11.7 microg g(-1) cr (95% CI 7.0-19.6) post-shift to 21.9 microg g(-1) cr (95% CI 13.3-36.3) (p < 0.01) in the next morning in 24 non-snuffing non-smokers before the smoking ban. A substantial reduction of airborne nicotine and total dust was observed after the introduction of a smoking ban in bars and restaurants. The urinary cotinine levels were reduced in non-smokers. The decline found in smokers may suggest a reduction in the amount of smoking after intervention. In non-smokers cotinine concentrations were higher based on urine sampled the morning after a shift than based on urine sampled immediately post-shift.  相似文献   
28.
Thin sediment capping is a commonly used technique to prevent mobilization of contaminants from sediments into the environment. A 70‐m‐deep subaqueous confined disposal facility (CDF, 350,000 m2) at Malmøykalven, Oslofjord, which received dredged contaminated sediments from Oslo Harbor, was capped with 148,900 m3 of sand in 2009. This research serves as a case study regarding some of the key considerations involved with the cap placement and monitoring of the cap layer. Uncertainty is included in all the cap thickness monitoring methods and a combined use of them provided a better understanding of the cap coverage and structure at the site. An open water disposal model (STFATE) was used to simulate the behavior of the barge‐released cap material. The modeling results were consistent with field observations regarding the material spread, and the results provided insight into the relatively high material losses calculated. Better knowledge obtained of material settling resulted in cap properties and cap monitoring methods that are useful when planning similar operations. ©2015 Wiley Periodicals, Inc.  相似文献   
29.
Many regions in Africa are currently being converted from subsistence to cash crop farming such as cotton. Agricultural intensification is usually accompanied by increased use of pesticides, which can have an impact on non-target organisms. Bats are particularly sensitive to insecticide loads while providing substantial ecosystem services as predators of herbivorous insects. In this study, pesticide residues in bats in a landscape in northern Benin were investigated, which spanned a land use gradient from an agricultural zone dominated by cotton farms, through a buffer zone, and into a national park. Insecticides used in cotton cultivation, such as endosulfan, chlorpyrifos, flubendiamide, and spirotetramat, as well as persistent insecticides such as bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), lindane, and aldrine, were analysed. Insecticide residues detected in bats comprised DDT, endosulfan, and their corresponding transformation products. Maximum concentrations in the sampled bats were 11.2 mg/kg lipid of p,p′-DDE (median: 0.0136 mg/kg lipid) and 0.797 mg/kg lipid of β-endosulfan (median: below detection limit [DL]). While insecticide concentrations were below lethal concentrations our data suggest that DDT had probably been recently used in the study region, and larger scale use would pose an increased risk for bat populations due to the high biomagnification of DDT.  相似文献   
30.
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.  相似文献   
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