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1.
挪威多领域环保优先政策   总被引:2,自引:0,他引:2  
为了达到挪威在国际协议中承诺的环保目标,政府的战略是制定一套综合环保政策。在此情况下,改善环境的措施需要在多个领域中实施。为此,每一个公共行政部门在制定所有的计划和发展规划时,有责任确保突出考虑环境问题。为了检查各个部门环保责任的完成,每个政府部门在年度预算中,都必须提出并量化其决定实施的环保措施。  相似文献   
2.
To predict the coherence in local responses to large-scale climatic forcing among aquatic systems, we developed a generalized approach to compare long-term data of dimictic water bodies based on phenomenologically defined hydrographic events. These climate-sensitive phases (inverse stratification, spring overturn, early thermal stratification, summer stagnation) were classified in a dual code (cold/warm) based on threshold temperatures. Accounting for a latitudinal gradient in seasonal timing of phases derived from gradients in cumulative irradiation (2.2?days per degree latitude), we found a high spatial and temporal coherence in warm–cold patterns for six lakes (84?%) and the Baltic Sea (78?%), even when using the same thresholds for all sites. Similarity to CW-codes for the North Sea still was up to 72?%. The approach allows prediction of phase-specific warming trends and resulting instantaneous or time-delayed ecological responses. Exemplarily, we show that warming during early thermal stratification controls food-web-mediated effects on key species during summer.  相似文献   
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Hoekman D  Dreyer J  Jackson RD  Townsend PA  Gratton C 《Ecology》2011,92(11):2063-2072
Aquatic insects are a common and important subsidy to terrestrial systems, yet little is known about how these inputs affect terrestrial food webs, especially around lakes. Myvatn, a lake in northern Iceland, has extraordinary midge (Chironomidae) emergences that result in large inputs of biomass and nutrients to terrestrial arthropod communities. We simulated this lake-to-land resource pulse by collecting midges from Myvatn and spreading their dried carcasses on 1-m2 plots at a nearby site that receives very little midge deposition. We hypothesized a positive bottom-up response of detritivores that would be transmitted to their predators and would persist into the following year. We sampled the arthropod community once per month for two consecutive summers. Midge addition resulted in significantly different arthropod communities and increased densities of some taxa in both years. Detritivores, specifically Diptera larvae, Collembola, and Acari increased in midge-addition plots, and so did some predators and parasitoids. Arthropod densities were still elevated a year after midge addition, and two years of midge addition further increased the density of higher-order consumers (e.g., Coleoptera and Hymenoptera). Midge addition increased arthropod biomass by 68% after one year and 108% after two years. By manipulating the nutrient pulse delivered by midges we were able to elucidate food web consequences of midge deposition and spatial and temporal dynamics that are difficult to determine based on comparative approaches alone. Resources cross ecosystem boundaries and are assimilated over time because of life-history strategies that connect aquatic and terrestrial food webs and these systems cannot be fully understood in isolation from each other.  相似文献   
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A simple and cheap device, which allows a controlled and continuous food supply of suspension feeding animals in long term experiments, has been developed and is described.  相似文献   
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To investigate waste water treatment plants (WWTPs) as sources of polyfluorinated compounds (PFCs), polybrominated diphenyl ethers (PBDEs) and synthetic musk fragrances to the atmosphere, air samples were simultaneously taken at two WWTPs and two reference sites using high volume samplers. Contaminants were accumulated on glass fiber filters and PUF/XAD-2/PUF cartridges, extracted compound-dependent by MTBE/acetone, methanol, or hexane/acetone and detected by GC-MS or HPLC-MS/MS. Total (gas + particle phase) concentrations ranged from 97 to 1004 pg m−3 (neutral PFCs), <MQL to 13 pg m−3 (ionic PFCs), 5781 to 482,163 pg m−3 (musk fragrances) and <1 to 27 pg m−3 (PBDEs) and were usually higher at WWTPs than at corresponding reference sites, revealing that WWTPs can be regarded as sources of musk fragrances, PFCs and probably PBDEs to the atmosphere. Different concentrations at the two WWTPs indicated an influence of WWTP size or waste water origin on emitted contaminant amounts.  相似文献   
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This research was designed to address the potential for germination and growth effects in bush beans (Phaseolus vulgaris L. var. Bush Blue Lake) from hexavalent chromium in Orocol TL, a proprietary chromated, zinc-phosphate compound added to DOE cooling water systems for corrosion inhibition. Studies were conducted at low and high Orocol TL concentrations in the soil by adjusting soil pH and the percent of organic matter. Germination effects were determined for seeds germinated in soils adjusted to differing pH ranges (4–4.5, 5–5.5, and 6.5–7), levels of organic matter (1.8%, 3%, and 5%), and Orocol TL amendments (control of 0, 10, and 500 μg/g chromium). Growth responses (effects) were determined from plants cultured in the same soil treatment combinations as described for the germination study. High levels (500 μg/g) of hexavalent chromium in soil (as Orocol TL) affected germination and growth, while a high level of organic matter significantly reduced chromium toxicity on germination. At lower chromium concentrations there was significant uptake by all plant parts, with a corresponding reduction in biomass of leaves. Consequently, adjustments of soil pH from 4.0 to 7.0 appear to have no significant effect on chromium uptake in plants. Increasing the organic matter level to 5%, while decreasing the toxicity of high chromium levels to germinating seed, did not affect chromium uptake.  相似文献   
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In Malaysia, various efforts have been introduced to increase the knowledge, skills and awareness of citizens to the benefit of the environment by means of a variety of programmes. However, uncertainty about the effectiveness of environmental education programmes and the way they contribute to sustainability still exists. This paper reports on an evaluation of the Kelab Pencinta Alam (KPA) (School Nature Clubs) programme organised by the Malaysia Nature Society and the Forest Research Institute of Malaysia. The Kellogg Logic Model was used as an evaluative instrument as the impact of the programme had to be determined. This was done through questionnaires to teachers and principals in KPA schools. School visits were also undertaken to evaluate workplace success and to validate the findings from the questionnaires. Overall, the evaluation showed a high level of success for the programme.  相似文献   
10.
The focus of this work was to investigate an enzymatic liquefaction of MSW organics, paper and cardboard. Liquefaction trials were conducted in different trial volumes: 50 g lab-scale trials and 50 kg vessel-tests and evaluated based on particle size and viscosity. The viscosity results showed that Celluclast 1.5 L had the singular significant effect on liquefaction of model MSW. No effect of α-amylase, protease and interaction in between and with cellulases on viscosity and particle size distribution was found in this study. Degradable material with a particle size above 1 mm after treatment was evaluated using SEM microscopy. These results showed that paper particles were the main obstacles needing additional treatment in order to become fully liquefied. In a pilot scale test treating authentic MSW; more than 90% of initial organic and paper dry matter (DM) was recovered as liquid slurry after sieving through a 5-mm sieve. These tests were performed at up to 35% DM, showing that this process can easily manage high DM loadings. MSW enzymatic liquefaction promotes the separation of organics and paper from solids, which facilitate the use of these degradable fractions, with minimal loss, capable to enter a biogas plant through existing pipes.  相似文献   
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