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91.
Satellite-tracking of 15 White-naped Cranes ( Grus vipio ) from their Japanese wintering grounds through the Korean Peninsula shows that there are four important regions for conserving migrant cranes: the Three Rivers Plain, the People's Republic of China; Lake Khanka, Russia; Kumya, North Korea; and—most importantly—the demilitarized zone of the Korean Peninsula. Two sites along the Korean demilitarized zone, Panmunch'om and Ch'olwon, were the most heavily used stopover sites, and they present complex international conservation challenges. Cranes stopped at these sites for up to 87.1% of their total migration time; cranes migrating to Zhalong Nature Reserve, China, made it their only lengthy stop. We report the migration routes and the importance of the identified stopover sites, and we outline conservation issues at those sites.  相似文献   
92.
93.
Objective: The objective of this study was to estimate the likely reduction in road trauma associated with the implementation of effective interventions to reduce road trauma among young Australians.

Methods: A desktop evaluation was conducted to model the likely reduction in road trauma (deaths and serious injuries resulting in hospitalization) among young people aged 17–24 years residing in Queensland, New South Wales, and Victoria. Potential interventions were identified using a rapid literature review and assigned a score based on evidence of effectiveness and implementation feasibility with the 3 highest scoring interventions included in the modeling. Likely reduction in road trauma was estimated by applying the average risk reduction effect sizes for each intervention to baseline risk (passenger or driver death or serious injury per 100,000 population) of road trauma for young Australians. Point estimates were calculated for the potential number of deaths and serious injuries averted in each state and per 100,000 population, with a one-way sensitivity analysis conducted using uncertainty ranges identified.

Results: Peer passenger and night driving restrictions as well as improved vehicle safety measures had the greatest potential to reduce road trauma. Peer passenger restrictions could avert 14 (range: 5–24) and 24 (range: 8–41) hospitalizations per year in Queensland and New South Wales, respectively, and night driving restrictions could avert 17 (range: 7–26), 28 (range: 12–45), and 13 (range: 6–21) hospitalizations annually in Queensland, New South Wales, and Victoria. These interventions reduced fatalities by less than 1 death annually in each state. Improved vehicle safety measures could avert 0–3, 0–4, and 0–3 deaths and 3–91, 4–156, and 2–75 hospitalizations in Queensland, New South Wales, and Victoria.

Conclusions: Key elements of graduated licensing (peer passenger and night driving restrictions) along with vehicle safety interventions offer modest but practically significant reductions in road trauma for young Australians. State governments need to revise current legislation to ensure that these reductions in road trauma can be realized.  相似文献   

94.
Objective: The goal of this study was to investigate the influence of the occupant characteristics on seat belt force vs. payout behavior based on experiment data from different configurations in frontal impacts.

Methods: The data set reviewed consists of 58 frontal sled tests using several anthropomorphic test devices (ATDs) and postmortem human subjects (PMHS), restrained by different belt systems (standard belt, SB; force-limiting belt, FLB) at 2 impact severities (48 and 29 km/h). The seat belt behavior was characterized in terms of the shoulder belt force vs. belt payout behavior. A univariate linear regression was used to assess the factor significance of the occupant body mass or stature on the peak tension force and gross belt payout.

Results: With the SB, the seat belt behavior obtained by the ATDs exhibited similar force slopes regardless of the occupant size and impact severities, whereas those obtained by the PMHS were varied. Under the 48 km/h impact, the peak tension force and gross belt payout obtained by ATDs was highly correlated to the occupant stature (P =.03, P =.02) and body mass (P =.05, P =.04), though no statistical difference with the stature or body mass were noticed for the PMHS (peak force: P =.09, P =.42; gross payout: P =.40, P =.48). With the FLB under the 48 km/h impact, highly linear relationships were noticed between the occupant body mass and the peak tension force (R2 = 0.9782) and between the gross payout and stature (R2 = 0.9232) regardless of the occupant types.

Conclusions: The analysis indicated that the PMHS characteristics showed a significant influence on the belt response, whereas the belt response obtained with the ATDs was more reproducible. The potential cause included the occupant anthropometry, body mass distribution, and relative motion among body segments specific to the population variance. This study provided a primary data source to understand the biomechanical interaction of the occupant with the restraint system. Further research is necessary to consider these effects in the computational studies and optimized design of the restraint system in a more realistic manner.  相似文献   

95.
A Method for Setting the Size of Plant Conservation Target Areas   总被引:3,自引:0,他引:3  
Abstract: Realistic time frames in which management decisions are made often preclude the completion of the detailed analyses necessary for conservation planning. Under these circumstances, efficient alternatives may assist in approximating the results of more thorough studies that require extensive resources and time. We outline a set of concepts and formulas that may be used in lieu of detailed population viability analyses and habitat modeling exercises to estimate the protected areas required to provide desirable conservation outcomes for a suite of threatened plant species. We used expert judgment of parameters and assessment of a population size that results in a specified quasiextinction risk based on simple dynamic models. The area required to support a population of this size is adjusted to take into account deterministic and stochastic human influences, including small-scale disturbance, deterministic trends such as habitat loss, and changes in population density through processes such as predation and competition. We set targets for different disturbance regimes and geographic regions. We applied our methods to Banksia cuneata, Boronia keysii, and Parsonsia dorrigoensis, resulting in target areas for conservation of 1102, 733, and 1084 ha, respectively. These results provide guidance on target areas and priorities for conservation strategies.  相似文献   
96.
The Northern Colorado Front Range (NCFR) has been in exceedance of the ozone National Ambient Air Quality Standard (NAAQS) since 2004, which has led to much debate over the sources of ozone precursors to the region, as this area is home to both the Denver, CO, metropolitan area and the Denver–Julesburg Basin, which has experienced rapid growth of oil and natural gas (O&NG) operations and associated emissions. Several recent studies have reported elevated levels of atmospheric volatile organic compounds (VOCs) as a result of O&NG emissions and the potential for significant ozone production from these emissions, despite implementation of stricter O&NG VOC emissions regulations in 2008. Approximately 88% of 1-hr elevated ozone events (>75 ppbv) occur during June–August, indicating that elevated ozone levels are driven by regional photochemistry. Analyses of surface ozone and wind observations from two sites, namely, South Boulder and the Boulder Atmospheric Observatory, both near Boulder, CO, show a preponderance of elevated ozone events associated with east-to-west airflow from regions with O&NG operations in the N-ESE, and a relatively minor contribution of transport from the Denver Metropolitan area to the SE-S. Transport from upwind areas associated with abundant O&NG operations accounts for on the order of 65% (mean for both sites) of 1-hr averaged elevated ozone levels, while the Denver urban corridor accounts for 9%. These correlations contribute to mounting evidence that air transport from areas with O&NG operation has a significant impact on ozone and air quality in the NCFR.

Implications: This article builds on several previous pieces of research that implied significant contributions from oil and natural gas emissions on ozone production in the Northern Colorado Front Range. By correlating increased ozone events with transport analyses we show that there is a high abundance of transport events with elevated ozone originating from the Denver–Julesburg oil and natural gas basin. These findings will help air quality regulators to better assess contributing sources to ozone production and in directing policies to curb ozone pollution in this region.  相似文献   

97.
Planning for environmental justice in an urban national park   总被引:1,自引:0,他引:1  
Urban national parks were designed in the 1970s to bring nature and recreational opportunities to socio-economically disadvantaged communities in the USA. Using the theoretical frame of environmental justice, this paper discusses findings of a recent survey of visitors to Los Angeles' Santa Monica Mountains National Recreation Area – the United States' largest urban national park. Findings show park visitors were predominantly white, affluent, and lived nearby. People of colour travelled further, were significantly less likely to be return visitors, and were less inclined to use the park for active recreation. Seemingly, this park fails to meet the needs of the disadvantaged urban communities for whom it was created, a problem that may also affect other parks in the United States and potentially parks in other countries. Park planners and managers can take practical steps to increase accessibility to this park for people of colour and low-income earners, and should monitor other parks for patterns of ethno-racially differentiated access and utilisation.  相似文献   
98.
99.
Despite heavy insecticide usage in urban areas, only a few studies have investigated the impact of current-use insecticides on benthic invertebrates in urban streams. The objective of this study was to measure the presence and concentration of current-use pesticides in sediments of residential streams in central Texas. Additionally, toxicity of these sediments to Hyalella azteca was evaluated. Sediment samples were collected from several sites in urban streams over the course of a year, of which, 66% had greater than one toxic unit (TU) of insecticide. Bifenthrin was the greatest contributor accounting for 65% of the TUs, and sediment toxicity to H. azteca correlated with the magnitude of total insecticides and bifenthrin TUs. The results of this study further raise concerns over the environmental consequences posed by many current-use insecticides, especially pyrethroids, in urban settings.  相似文献   
100.
Todd, M. Jason, George Vellidis, R. Richard Lowrance, and Catherine M. Pringle, 2009. High Sediment Oxygen Demand Within an Instream Swamp in Southern Georgia: Implications for Low Dissolved Oxygen Levels in Coastal Blackwater Streams. Journal of the American Water Resources Association (JAWRA) 45(6):1493‐1507. Abstract: Sediment oxygen demand (SOD) is considered a critical and dominant sink for dissolved oxygen (DO) in many river systems including blackwater streams and is often poorly investigated or roughly estimated in oxygen budgets. The purposes of this study are to (1) characterize and document the magnitude and variability of SOD in representative instream swamps found on the Georgia Coastal Plain; (2) predict SOD from more readily measured parameters such as soil, sediment, and litter organic carbon; and (3) obtain an accurate representation of SOD values within this understudied habitat to help improve water quality models and the continued development of DO as an appropriate water quality standard. Results show SOD rates ranging from 0.491 to 14.189 g O2/m2/day, up to 18 times higher than values reported for southeastern sandy‐bottomed streams and suggest that instream swamps are repositories of large amounts of organic matter and are thus areas of intense oxygen demand and a major factor in determining the oxygen balance of the watershed as a whole. These areas of intense oxygen demand in relatively unimpacted areas indicate that low DO concentrations may be a natural phenomenon. SOD rates were significantly correlated (alpha = 0.05) with a number of sediment parameters, with organic carbon and total organic carbon being the best predictors of SOD rate. When developing water quality models, managers should pay closer attention to the influence of SOD as it plays a critical role in determining DO levels within instream swamps and the river system.  相似文献   
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