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951.
A cradle-to-grave life cycle assessment was done to identify the environmental impacts related to alkaline copper quaternary (ACQ)-treated lumber used for decking and to determine how the impacts compare to the primary alternative product, wood plastic composite (WPC) decking. A model of ACQ-treated lumber life cycle stages was created and used to calculate inputs and outputs during the lumber production, treating, use, and disposal stages. Lumber production data are based on published sources. Primary wood preservative treatment data were obtained by surveying wood treatment facilities in the United States. Product use and disposal inventory data are based on published data and professional judgment. Life cycle inventory inputs, outputs, and impact indicators for ACQ-treated lumber were quantified using functional units of 1000 board feet and per representative deck (assumed to be 320 square feet (30 square meters) of surface decking material) per year of use. In a similar manner, an inventory model was developed for the manufacture, use, and disposal of the primary alternative product, WPC. Impact indicator values, including greenhouse gas (GHG) emissions, fossil fuel use, water use, acidification, smog forming potential, ecological toxicity, and eutrophication were quantified for each of the two decking products. National normalization was done to compare the significance of a representative deck surface per year of use to a family’s total annual impact footprint.If an average U.S. family adds or replaces a deck surfaced with ACQ-treated lumber, their impact “footprint” for GHG emissions, fossil fuel use, acidification, smog forming potential, ecological toxicity, and eutrophication releases each is less than one-tenth of a percent of the family’s annual impact. ACQ-treated lumber impacts were fourteen times less for fossil fuel use, almost three times less for GHG emissions, potential smog emissions, and water use, four times less for acidification, and almost half for ecological toxicity than those for WPC decking. Impacts were approximately equal for eutrophication. 相似文献
952.
953.
Lynne Van Herwerden J. Howard Choat Stephen J. Newman Matthieu Leray Grethe Hillersøy 《Marine Biology》2009,156(8):1595-1607
Here the population genetic structure of an ecologically and economically important coral reef fish, the coral trout Plectropomus leopardus, is investigated in the context of contemporary and historical events. Coral trout were sampled from four regions (six locations)
and partial mtDNA D-loop sequences identified six populations (Fst = 0.89209, P < 0.0001): Scott Reef and the Abrolhos Islands in west Australia; the Great Barrier Reef (GBR), represented by northern and
southern GBR samples; New Caledonia and Taiwan, with Taiwan containing two genetic lineages. Furthermore, this study identified
source and sink populations within and among regions. Specifically, the northern population in west Australia (Scott Reef)
was identified, as the source for replenishment of the Abrolhos population, whilst New Caledonia was a source for recruitment
to the GBR. Based on these insights from a single mtDNA marker, this study will facilitate the development of rational management
plans for the conservation of P. leopardus populations and therefore mitigate the risk of population declines from anthropogenic influences. 相似文献
954.
Juan-Gabriel Cegarra-Navarro Stephen Eldridge Aurora Martinez-Martinez 《Journal of environmental psychology》2010
The Spanish hospitality industry is facing environmental challenges which require organizations and individuals to learn new skills and practices and create new environmental knowledge. Understanding the nature and role of prior knowledge for sustainable development is a necessary step towards understanding if new environmental practices will be adopted successfully. This research focuses on unlearning and its impact on environmental knowledge by carrying out an empirical investigation of the unlearning context in 127 Spanish hospitality companies. The findings indicate that a process for consolidating emergent understandings would appear to be an intermediary step between the forgetting of old knowledge and the application of new environmental knowledge. Consequently, it is important that managers provide an appropriate unlearning context to support the openness of individuals to new ideas and environmental awareness. Otherwise, individuals may be fearful of or confused by the prospect of unlearning old habits and routines. 相似文献
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956.
Stephen Marshall Vincent Pettigrove Ary Hoffmann 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1716-1725
Several factors can contribute to the ecological degradation of stream catchments following urbanization, but it is often difficult to separate their relative importance. We isolated the impact of polluted sediment on the condition of an urban stream in Melbourne, Australia, using two complementary approaches. Using a rapid bioassessment approach, indices of stream condition were calculated based on macroinvertebrate field surveys. Urban stream reaches supported impoverished macroinvertebrate communities, and contained potentially toxic concentrations of heavy metals and hydrocarbons. Using a field microcosm approach, a bioassay was carried out to assess sediment pollution effects on native macroinvertebrates. Sediment from urban sites substantially altered the microcosm macroinvertebrate community, most likely due to elevated heavy metal and hydrocarbon concentrations. Macroinvertebrate surveys combined with a bioassay approach based on field microcosms can help isolate the effect of stream pollutants in degraded ecosystems. 相似文献
957.
958.
Mate guarding is a male strategy to gain access to receptive females but often results in antagonistic interactions between
the sexes because of different costs/benefits of guarding. In addition to social, morphological, and physiological parameters,
the type of mating system should also affect the strength of the conflict and thus the guarding duration. Specifically, when
compared to females, self-compatible hermaphrodites might have reduced benefits of outcrossing. We investigated mate guarding
in dioecious (co-presence of females and males) and androdioecious (co-presence of hermaphrodites and males) branchiopod crustaceans.
Both sexes in androdioecious systems should shift their guarding times to lower values relative to dioecious systems because
(1) androdioecious males are present in lower percentages than dioecious males and thus encounter rates with receptive mates
are relatively greater for them; and (2) hermaphrodites should have low incentive to incur high costs of mate guarding, having
the alternative of self-fertilization, and thus should be highly eager to resist. While females preferred short guarding times,
when allowed to control the guarding duration (males tethered), dioecious males did not increase their guarding duration when
females (treated with muscular relaxant) could not resist, in contrast to what has previously been found for androdioecious
males. This indicates that hermaphrodites are more willing to resist mate guarding than females. The among-species comparisons
supported our hypotheses: compromised guarding times were significantly lower in androdioecious than in dioecious species.
The introduction of a parameter (mating system) not previously investigated in mate guarding models resulted in a powerful
test of mate guarding theory, adding a valuable contribution to our understanding of intersexual conflict. 相似文献
959.
960.