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131.
132.
In the aftermath of the 9/11 disaster, Mayor Bloomberg of New York City unveiled an aggressive budget plan that included the temporary suspension of glass and plastics recycling. This was considered by many to be anti-environmental, but the results of this study show that for lack of markets, even at zero or negative prices, nearly 90% of the plastic and glass set aside by thoughtful New Yorkers was transported to materials recovery facilities (MRFs) and from there to landfills. Sending bales of plastics to landfills is not limited to New York City. It is an environmental paradox that the United States is digging up new oil fields in pristine areas and, at the same time, continues to convert greenfields to brownfields by burying nearly 20 million tons of plastic fuel annually. The study also determined that at the present rate of source separation, estimated to be less than 30% of the available recyclables in 1999, building large, modern MRFs may increase substantially the rate of New York City recycling and also allow single-stream collection of commingled recyclables, as is done in Phoenix, AZ. Single-stream collection simplifies separation at the source by citizens and increases the amount of collected recyclables. Also, because collection represents a large fraction of the costs of waste management, it may have a significant economic advantage.  相似文献   
133.
Environmental Chemistry Letters - Most fossil fuel-derived polymers used for food packaging are non-biodegradable and induce pollution by microplastic, calling for safer material. Here we review...  相似文献   
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Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
136.
Summary The host utilization process of insect parasitoids can be described by three stages of (1)habitatlocation, (2)host-location, and (3)host-acceptance andoviposition. There are 19 systems in which chemicals used inhabitat-location have been identified, 12 systems in which chemical cues leading tohost-location have been identified, and 16 systems in which chemicals elicitinghost-acceptance andoviposition have been identified. Both the chemical class and the source of the infochemical change with the stage of the host utilization process. Semiochemicals identified in thehabitatlocation stage were predominantly aldehydes, alcohols, sulfur-containing compounds, esters and terpenes, and were equally likely to be from the host-plant of the host, or from the host itself. Semiochemicals identified in thehost-location stage were sugars, alkanes, terpenes and heterocyclic aromatic compounds and 3/4 of them were host-produced cues. In thehost-acceptance andoviposition stage the identified semiochemicals were all produced by the host and were proteins, amino acids, triglycerides and salts. The importance of recognizing specific cues involved in host utilization by parasitoids is discussed, and suggestions for future research are made.  相似文献   
137.
Abstract: Conservation biologists have developed powerful tools for reserve selection and design over the past two decades, yet seldom are protected areas actually designed on scientific grounds. Using fundamental biological and socioeconomic principles of conservation science, we designed a new protected area and its multiple-use zone on the Masoala Peninsula in the humid forest zone of Madagascar. The explicit design criteria determined the data gathered for the work, which included (1) spatial distribution and quality of habitat, (2) the areas and species at greatest risk, (3) the relationship between environmental gradients and species distributions, (4) current and predicted human settlement and land and resource use, and (5) the economic potential of natural forest management as an alternative to deforestation. We used a geographic information system to integrate these data layers and applied the design criteria to develop a park proposal that balanced human and wildlife needs. The proposal won the approval of local residents, and a national decree in 1997 designated 2100 km2 of rainforest and three satellite marine reserves as the Masoala National Park, with a surrounding multiple-use zone of approximately 1000 km2. The new park is Madagascar's largest protected area and protects more lowland (<400 m) humid forest habitat than the entire reserve system combined, a significant step forward in conserving a globally important ecoregion. Consideration of local needs and the national economy was a key element in gaining approval for the Masoala Park. Such an approach toward reserve design could be applied elsewhere to improve chances of establishing and maintaining protected areas over the long term.  相似文献   
138.
Environmental Chemistry Letters - Water contamination is an environmental burden for the next generations, calling for advanced methods such as adsorption to remove pollutants. For instance,...  相似文献   
139.
The diagram constructed for selection of sampling methods indicates that, for a systematic error, E ≤ 13%, grab sampling (GS) may be used to characterize effluents with variation coefficient of flow ≤ 120% and of contaminant concentrations ≤ 10%. For the whole studied range of variation coefficient of contaminant concentrations (2–82%), time-proportional compositing (TC) method may be applied with E ≤ 10% for effluents characterized by variation coefficients in flow < 90%. The more complicated flow-proportional compositing (FC) method is required only for effluents with larger variation coefficients or to produce more precise results. The diagram constructed for selection of sampling frequencies indicates that sequential sampling at intervals of approximately 60 min may be applied with E ≤ 10% for effluents characterized by variation coefficients ≤ 30%. Practical application of the diagrams, constructed using normal series, was checked against monitoring data from two pulp and paper mills in Vietnam. The two diagrams provided results on sampling methods and frequencies in good agreement with those obtained from actual monitoring data with percentages of agreement cases of 80 and 75%, respectively. The approach was applied in design of a monitoring program at the Bai Bang integrated pulp and paper mill in Vietnam.  相似文献   
140.
Regional Environmental Change - Social-ecological changes, brought about by the rapid growth of the aquaculture industry and the increased occurrence of climatic stressors, have significantly...  相似文献   
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