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71.
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Many development projects intended to exploit natural resourcesare occurring in fragile ecosystems, and therefore the need forsound biodiversity assessment and monitoring programs is growing.Large mammals are important components of these fragile ecosystems, yet there are few strategies that attempt to assess and monitor entire large mammal communities in relation to development projects. We propose the use of two indices applied within a framework of adaptive management. An occurrence indexassesses the composition and distribution of large mammals at a site, and an abundance index monitors the abundance of large mammals over time in relation to development. We discuss the design, applicability and effectiveness of these indices based onour experience with a natural gas development project in the Amazon forests of southeastern Peru.  相似文献   
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The Surface Mining Control and Reclamation Act of 1977 requires that coal mine sites in the United States be reclaimed to establish vegetative cover that is diverse, native, and capable of plant succession. However, there is a question as to whether vegetation established on coal mine sites reclaimed with biosolids is diverse and capable of plant succession. The influx of nutrients with the addition of biosolids leads to long-term dominance by early-successional species, most notably grasses, and consequently, a low establishment of woody and volunteer species. Additionally, many grass species commonly planted in reclamation have aggressive growth habits that lead to their dominance in coal mine plant communities. The establishment and growth of selected grass mixes was evaluated to determine whether alternative grass mixes would be less competitive with woody and volunteer species as compared to commonly used grass mixes. Percent vegetative cover, species richness, and the survival of direct-seeded woody species were assessed for each treatment grass mixture. It was found that Poa compressa and a mixture of P. compressa, Panicum virgatum, and Trifolium repens provided adequate coverage while still allowing the highest species richness and survival of woody species. Use of these species mixtures in coal mine reclamation with biosolids in the eastern United States would likely lead to establishment of a more species-rich plant community with a greater woody species component while still providing erosion control and site protection.  相似文献   
75.
Objective: The objective of this study was to investigate vehicle factors associated with child restraint tether use and misuse in pickup trucks and evaluate 4 labeling interventions designed to educate consumers on proper tether use.

Methods: Volunteer testing was performed with 24 subjects and 4 different pickup trucks. Each subject performed 8 child restraint installations among the 4 pickups using 2 forward-facing restraints: a Britax Marathon G4.1 and an Evenflo Triumph. Vehicles were selected to represent 4 different implementations of tether anchors among pickups: plastic loop routers (Chevrolet Silverado), webbing routers (Ram), back wall anchors (Nissan Frontier), and webbing routers plus metal anchors (Toyota Tundra). Interventions included a diagram label, Quick Response (QR) Code linked to video instruction, coordinating text label, and contrasting text tag.

Results: Subjects used the child restraint tether in 93% of trials. However, tether use was completely correct in only 9% of trials. An installation was considered functional if the subject attached the tether to a tether anchor and had a tight installation (ignoring routing and head restraint position); 28% of subjects achieved a functional installation. The most common installation error was attaching the tether hook to the anchor/router directly behind the child restraint (near the top of the seatback) rather than placing the tether through the router and attaching it to the anchor in the adjacent seating position. The Nissan Frontier, with the anchor located on the back wall of the cab, had the highest rate of correct installations but also had the highest rate of attaching the tether to components other than the tether anchor (seat adjustor, child restraint storage hook, around head restraint). None of the labeling interventions had a significant effect on correct installation; not a single subject scanned the QR Code to access the video instruction. Subjects with the most successful installations spent extensive time reviewing the vehicle manuals.

Conclusion: Current implementations of tether anchors among pickup trucks are not intuitive for child restraint installations, and alternate designs should be explored. Several different labeling interventions were ineffective at achieving correct tether use in pickup trucks.  相似文献   

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Perfluorooctane sulfonic acid (PFOS) is a persistent and ubiquitous environmental contaminant that has been detected in organisms worldwide. Here, we evaluate whether long-term (1 and 4 months) exposure to PFOS contamination affects the behavioural performance of freshwater larvae of the damselfly Enallagma cyathigerum (Insecta: Odonata). Our results show reduced behavioural performance with increasing PFOS concentration. In 1 month exposed larvae, no observed effect concentrations (NOECs) were 100 μg/L for general activity. In 4 months exposed larvae, NOECs were 10 μg/L, for each behavioural trait, except swimming acceleration of male larvae where the NOEC was 100 μg/L. When faced with PFOS concentrations above the NOEC, E. cyathigerum larvae were less active, less capable to escape a simulated predator attack and less efficient in foraging. Together, our results show that damselfly larvae suffer reduced survival-related behavioural performance.  相似文献   
78.
This paper examines the attitudes and perceptions of local people about ecological resources, environmental hazards, and future land use of the Idaho National Engineering and Environmental Laboratory (INEEL). Such monitoring of attitudes is an important aspect of environmental assessment. We interviewed 262 people who attended the 42nd Annual Free Fishermen's Breakfast at St. Anthony, Idaho, on 23 March 1997. We tested the null hypotheses that there were no differences in perceptions about ecological resources, hazards and future land use of INEEL as a function of gender, age, education, and place of residence. Dumping trash in the ocean and cutting rainforests rated as the environmental problems of highest concern, and ozone, radon and high voltage lines rated the lowest; cleaning up Department of Energy sites rated intermediate. Respondents were most willing to expend government funds to make drinking water clean. Three significant differences were found: 1) women rated environmental problems as more severe than did men, and women were more willing to expend federal funds to solve these problems, 2) respondents under 30 years of age rated environmental problems as more severe than older people, and they were more willing to spend money to solve them, and, 3) respondents who had not finished high school were more concerned with environmental problems and were more willing to spend money to solve them than respondents with a high school education. Maintaining INEEL as a National Environmental Research Park (NERP) rated as the most preferred future land use, followed by continued reprocessing of nuclear materials and hunting. Using INEEL for housing and additional nuclear waste storage rated the lowest. Men rated grazing livestock and additional nuclear waste storage higher than did women. In general, respondents from 30 – 49 rated several economic uses (hunting, grazing livestock, growing crops) higher than did people in other age groups. Respondents with some college rated these economic uses higher than did respondents who had not graduated from high school. These results indicate that respondents living around INEEL believe that INEEL should continue with a reprocessing and NERP mission, but that other peripheral uses, such as hunting, hiking and grazing, should be allowed on some of the land. These views should aid in environmental assessment of the site, and in developing further management plans for INEEL.  相似文献   
79.
Recent studies suggest that human activities accelerate the production of reactive nitrogen on a global scale. Increased nitrogen emissions may lead to environmental impacts including photochemical air pollution, reduced visibility, changes in biodiversity, and stratospheric ozone depletion. In the last 50 yr, emissions of ammonia (NH3), which is the most abundant form of reduced reactive nitrogen in the atmosphere, have significantly increased as a result of intensive agricultural management and greater livestock production in many developed countries. These agricultural production practices are increasingly subject to governmental regulations intended to protect air resources. It is therefore important that an accurate and robust agricultural emission factors database exist to provide valid scientific support of these regulations. This paper highlights some of the recent work that was presented at the 2006 Workshop on Agricultural Air Quality in Washington, D.C. regarding NH3 emissions estimates and emission factors from agricultural sources in the U.S. and Europe. In addition, several best management practices are explored as the scientific community attempts to maximize the beneficial use of reactive nitrogen while simultaneously minimizing negative environmental impacts.  相似文献   
80.
Abstract: Residential water demand is a function of several factors, some of which are within the control of water utilities (e.g., price, water restrictions, rebate programs) and some of which are not (e.g., climate and weather, demographic characteristics). In this study of Aurora, Colorado, factors influencing residential water demand are reviewed during a turbulent drought period (2000‐2005). Findings expand the understanding of residential demand in at least three salient ways: first, by documenting that pricing and outdoor water restriction policies interact with each other ensuring that total water savings are not additive of each program operating independently; second, by showing that the effectiveness of pricing and restrictions policies varies among different classes of customers (i.e., low, middle, and high volume water users) and between predrought and drought periods; and third, in demonstrating that real‐time information about consumptive use (via the Water Smart Reader) helps customers reach water‐use targets.  相似文献   
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