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941.
The coverage of strategic environmental assessment (SEA) has been extended to all public sector policies, plans and programmes subject to Scottish jurisdiction. Evaluation of the arguments advanced by the Scottish Executive for using environmental assessment as a tool for environmental governance requires an exploration of some of the contested interpretations of the function of environmental assessment at a strategic level. The paper examines the implications of this extension of the European Union SEA Directive in the context of current arrangements to fit environmental assessment into the UK tradition of integrated policy appraisal. It considers the methodological implications of using SEA explicitly for improving public sector decision making at all levels and across all activities. This enables environmental effects to be taken into account at an early stage in the formulation of government policy, through a transparent system of assessment which encourages public participation. 相似文献
942.
The development and regulatory acceptance of monitored natural attenuation (MNA) as a remedial strategy has forever changed the field of environmental cleanup. MNA is continuing to develop but it is challenged by a lack of a clear definition for the appropriate application of the MNA strategy. This challenge has resulted in the lack of a significant record of restoration and site closure. Environmental professionals face challenges in providing guidance that addresses how to manage these sites when technologies, performance monitoring, and even environmental conditions are subject to further development, refinement, and/or altered perspectives. As our experience and institutional knowledge grows around the implementation of MNA, we have the opportunity to develop “second‐generation” management tools and procedures for optimizing sites utilizing MNA as a part of a comprehensive site management plan. This opportunity is the focus of the Enhanced Attenuation: Chlorinated Organics (EACO) Team of the Interstate Technology Regulatory Council (ITRC). The development of the “second‐generation” tools/procedures has included defining EA and evaluating, through the use of a national survey of state regulators, the experience with MNA and interest in EA. The results of these two efforts formed the basis for developing a framework that provides a “bridge” from active treatment to MNA. © 2007 Wiley Periodicals, Inc. 相似文献
943.
Groundwater at most underground storage tank (UST) spills sites in Kansas contains both methyl tertiary butyl ethylene (MTBE) and benzene, and both contaminants must be effectively treated to close the sites. Soil vacuum extraction, air sparging, and excavation are the most common treatment technologies in Kansas. To compare the relative performance of these conventional remedial technologies for treating MTBE as compared to benzene, 66 sites in the Kansas UST Trust Fund were identified that had initial concentrations of both MTBE and benzene above the reporting limit of 1 μg/L, and that had at least two rounds of analytical data. Sites were excluded from the comparison if the monitoring wells had free product. Of the 66 sites, 15 had met the clean‐up goal for benzene, and 50 had met the goal for MTBE. The extent of treatment for MTBE and benzene was calculated as the ratio of the highest concentration in any well at the site in the most recent round of sampling to the maximum concentration in any well at the site in the previous rounds of sampling. The extent of treatment was greater for MTBE (statistically significant at p = 0.032). The geometric mean of the extent of treatment in the 66 sites was 0.057 for MTBE, compared to 0.14 for benzene. In Kansas, conventional technologies removed MTBE from the source areas of groundwater plumes at least as effectively as they removed benzene. © 2003 Wiley Periodicals, Inc. 相似文献
944.
Integrating limnological characteristics of high mountain lakes into the landscape of a natural area 总被引:1,自引:0,他引:1
Gary L. Larson Andy Wones C. David McIntire Barbara Samora 《Environmental management》1994,18(6):871-888
A general conceptual watershed-lake model of the complex interactions among climatic conditions, watershed location and characteristics,
lake morphology, and fish predation was used to evaluate limnological characteristics of high mountain lakes. Our main hypothesis
was that decreasing elevation in mountainous terrain corresponds to an increase in diversity of watershed size and lake area,
depth, temperature, nutrient concentrations, and productivity. A second hypothesis was that watershed location and aspect
relative to climatic gradients within mountainous terrain influences the limnological characteristics of the lakes. We evaluated
these hypotheses by examining watershed location, aspect and size; lake morphology; water quality; and phytoplankton and zooplankton
community characteristics among high mountain forest and subalpine lakes in Mount Rainier National Park.
Although many of the comparisons between all forest and subalpine lakes were statistically insignificant, the results revealed
trends that were consistent with our hypotheses. The forest lake group included more lakes with larger watersheds, larger
surface areas, greater depths, higher concentrations of nutrients, and higher algal biovolumes than did the group of subalpine
lakes. Deep lakes, which were mostly of the forest lake type, exhibited thermal stratification and relatively high values
of some of the water-quality variables near the lake bottoms. However, the highest near-surface water temperatures and phytoplankton
densities and the taxonomic structures of the phytoplankton and zooplankton assemblages were more closely related to geographical
location, which corresponded to a west-east climate gradient in the park, than to lake type. Some crustacean and rotifer taxa,
however, were limited in distribution by lake type.
Fish predation did not appear to play an important role in the structure of the crustacean zooplankton communities at the
genus level with the exception of Mowich Lake, where crustacean taxa were absent from the zooplankton community. This was
the only lake inhabited by a true zooplanktivourous species of fish. 相似文献
945.
William L. Reichert Barbara L. French John E. Stein 《Environmental monitoring and assessment》1999,56(3):225-239
There is little information on exposure of marine mammals to genotoxic environmental contaminants. The 32P-postlabeling assay has been successfully used to assess exposure to genotoxic polycyclic aromatic compounds in fish and humans. In the present study, a preliminary investigation showed that polycyclic aromatic compound-like DNA adducts were present in hepatic tissues of harbor seals (Phoca vitulina richardsi) exposed to petroleum following the Exxon Valdez oil spill. However, for marine mammals, effects from changes in tissue condition on DNA recovery and quality is of concern, because tissue samples are often collected from animals that have been dead for unknown periods of time. To assess the effects of postmortem thermal history on DNA recovery from tissue and on DNA adduct quantitation, samples of harbor porpoise (Phocoena phocoena) hepatic tissue were incubated for up to 10 d at 4 and 30 °C. Only traces (<4 g) of hepatic DNA were recovered from 200 mg of tissue after incubation at 30 °C for 36 h. At 4 °C, DNA (50–130 g) was recovered from tissue incubated for up to 6 d; whereas DNA recovery at 10 d was minimal. Chromatograms of 32P-labeled DNA digests of liver tissue held at 4 and 30 °C and salmon sperm DNA held at 30 °C for 2 d had comparable profiles, suggesting that alteration of DNA bases had occurred during incubation of porpoise liver tissue. Moreover, the chromatograms of DNA extracted from liver tissues of harbor porpoises caught incidentally in a northwest Atlantic fishery, packed in ice and sampled several days later also exhibited similar altered DNA structures. Although, altered DNA structures that can interfere with the DNA adduct quantitation were present in autolyzed tissue, changes in the 32P-postlabeling chromatography conditions can decrease the interference. Moreover, in a study with tissues taken from California sea lions (Zalophus californianus) immediately postmortem and stored at –80 °C until processing, DNA structures associated with tissue breakdown were not observed. The DNA from sea lions, however, had putative age-dependent hepatic DNA modifications, which have a distinctive profile, and must be considered when evaluating exposure of marine mammals to polycyclic aromatic compounds. Overall, the findings showed that with attention to the postmortem thermal history of the tissue samples hepatic DNA adducts, as measured by 32P-postlabeling, have the potential to serve as a biological indicator of exposure of marine mammals to environmental genotoxic compounds. 相似文献
946.
Yellowjackets (Vespula pensylvanica) thermoregulate in response to changes in protein concentration 总被引:1,自引:0,他引:1
Social insects can modulate body temperature to increase foraging efficiency; however, little is known about how the relative value of protein resources affects forager body temperature. Such regulation may be important given that colony growth is often limited by protein availability. In this paper, we present what are, to our knowledge, the first data for social insects showing that thoracic temperatures (T (th)) of foragers increase with the protein content of food resources. In an introduced population of western yellowjacket (Vespula pensylvanica), we measured T (th) of foragers collecting high-quality protein (100% canned chicken) and low-quality protein (50% canned chicken, 50% indigestible alpha-cellulose by volume) at different ambient air temperatures (T (a)). Wasps foraging on 100% chicken consistently exhibited higher T (th) compared to wasps foraging on 50% chicken. After correcting for T (a), the mean T (th) for wasps collecting 100% chicken were 1.98 degrees C higher than those of individuals collecting 50% chicken. We suggest that this mechanism may increase foraging efficiency in this and other social wasp species. 相似文献
947.
Francesco Ciliberti Pierpaolo Pontrandolfo Barbara Scozzi 《Journal of Cleaner Production》2008,16(15):1579-1588
This paper analyzes the practices adopted and difficulties experienced by Small and Medium-sized Enterprises (SMEs) to transfer socially responsible behaviors to suppliers that operate in developing countries. In particular, a multiple case study was conducted on five Italian socially responsible SMEs. It was found that companies use different strategies as well as diverse management systems and tools to address Corporate Social Responsibility (CSR) issues along their supply chains (SCs). The paper is innovative mainly since few are the existing studies that investigate the CSR practices adopted by SMEs in the SC. Furthermore, it is argued that our research can be helpful to SME managers willing to deal with CSR issues along their SCs, especially when developing countries are involved. 相似文献
948.
Hill R Bryan SE McDonald P Wilson RC Smith AD 《Journal of environmental radioactivity》2008,99(1):20-34
Modelling calculations have been performed to predict the radiological impact of the sea to land transfer pathway to members of the public in North Wales from 1952 to 2004. The radionuclides of interest were (99)Tc, (137)Cs, (239,240)Pu and (241)Am and the exposure routes considered were food consumption, external and inhalation. The consumption of locally grown terrestrial food in the early to mid 1980s was the most significant source of exposure to all of the groups considered, with (239,240)Pu being the radionuclide contributing most to the dose. A maximum dose of 1.46muSvy(-1) was calculated for adult members of the critical consumption group in 1985, with doses for 2004 reducing to 0.59muSvy(-1). Despite the conservative approach of the dose calculations, the dose rate values are very low, less than 0.15% of the annual limit of 1000muSvy(-1) for the UK public from controlled radiation sources (excluding medical). 相似文献
949.
Daniel Chure Brooks B. Britt John A. Whitlock Jeffrey A. Wilson 《Die Naturwissenschaften》2010,97(4):379-391
Sauropod dinosaur bones are common in Mesozoic terrestrial sediments, but sauropod skulls are exceedingly rare—cranial materials
are known for less than one third of sauropod genera and even fewer are known from complete skulls. Here we describe the first
complete sauropod skull from the Cretaceous of the Americas, Abydosaurus mcintoshi, n. gen., n. sp., known from 104.46 ± 0.95 Ma (megannum) sediments from Dinosaur National Monument, USA. Abydosaurus shares close ancestry with Brachiosaurus, which appeared in the fossil record ca. 45 million years earlier and had substantially broader teeth. A survey of tooth
shape in sauropodomorphs demonstrates that sauropods evolved broad crowns during the Early Jurassic but did not evolve narrow
crowns until the Late Jurassic, when they occupied their greatest range of crown breadths. During the Cretaceous, brachiosaurids
and other lineages independently underwent a marked diminution in tooth breadth, and before the latest Cretaceous broad-crowned
sauropods were extinct on all continental landmasses. Differential survival and diversification of narrow-crowned sauropods
in the Late Cretaceous appears to be a directed trend that was not correlated with changes in plant diversity or abundance,
but may signal a shift towards elevated tooth replacement rates and high-wear dentition. Sauropods lacked many of the complex
herbivorous adaptations present within contemporaneous ornithischian herbivores, such as beaks, cheeks, kinesis, and heterodonty.
The spartan design of sauropod skulls may be related to their remarkably small size—sauropod skulls account for only 1/200th
of total body volume compared to 1/30th body volume in ornithopod dinosaurs. 相似文献
950.
Miriam Fischlein Timothy M. Smith Elizabeth J. Wilson 《Environmental Science & Policy》2009,12(7):778-790
An important subset of the utility sector has been scarcely explored for its ability to reduce carbon dioxide emissions: consumer-owned electric utilities significantly contribute to U.S. greenhouse gas emissions, but are often excluded from energy efficiency and renewable energy policies. They sell a quarter of the nation's electricity, yet the carbon impact of these sales is not well understood, due to their small size, unique ownership models, and high percentage of purchased power for distribution. This paper situates consumer-owned utilities in the context of emerging U.S. climate policy, quantifying for the first time the state-by-state carbon impact of electricity sales by consumer-owned utilities. We estimate that total retail sales by consumer-owned utilities account for roughly 568 million metric tons of CO2 annually, making this sector the 7th largest CO2 emitter globally, and examine state-level carbon intensities of the sector in light of the current policy environment and the share of COU distribution in the states. Based on efficiency and fuel mix pathways under conceivable regulations, carbon scenarios for 2030 are developed. 相似文献