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141.
Like many conservation organizations and federal and state agencies, The Nature Conservancy is in the process of large-scale planning and prioritization efforts. To improve the efficiency of these planning efforts, the Conservancy has developed a methodology for these efforts. The results of these planning efforts will be a conservation blueprint which identifies the conservation areas necessary for conserving biodiversity and a subset of those areas where the Conservancy will focus its immediate efforts over the next 10 years. The subset of all the conservation areas identified in the planning process help The Nature Conservancy determine where it will work. This subset of areas (referred to as action sites) is selected using a tool which ranks key criteria for each conservation area. These criteria include the current conservation status of each area, complementarity to other areas selected, the diversity and viability of targets at the area, the urgency and degree of threats to the targets, the feasibility or opportunity to abate the threats at the area and the leverage potential of working at a conservation area. Taken together, these criteria help planners to select the areas where they will focus their conservation efforts.  相似文献   
142.
Applying the concept of sustainability to invasive species management (ISM) is challenging but necessary, given the increasing rates of invasion and the high costs of invasion impacts and control. To be sustainable, ISM must address environmental, social, and economic factors (or “pillars”) that influence the causes, impacts, and control of invasive species across multiple spatial and temporal scales. Although these pillars are generally acknowledged, their implementation is often limited by insufficient control options and significant economic and political constraints. In this paper, we outline specific objectives in each of these three “pillars” that, if incorporated into a management plan, will improve the plan’s likelihood of sustainability. We then examine three case studies that illustrate how these objectives can be effectively implemented. Each pillar reinforces the others, such that the inclusion of even a few of the outlined objectives will lead to more effective management that achieves ecological goals, while generating social support and long-term funding to maintain projects to completion. We encourage agency directors and policy-makers to consider sustainability principles when developing funding schemes, management agendas, and policy.  相似文献   
143.
The recovery of ferrous and non ferrous metals from the bottom ashes is a common practice in the most part of Europe, both for the environmental advantages of their recycle and to avoid problems of swelling and expansion that metals can cause when bottom ashes are reused in concrete production or in road construction. This paper focuses on metal recovery from bottom ashes produced in Municipal Solid Waste (MSW) incinerators, with a particular focus on aluminium. A forecasting model was developed in order to evaluate the quantity of aluminium scraps recoverable from the bottom ashes. The model was applied to the Italian situation but its validity can be extended to other countries. Focusing on Italy, by applying conventional technologies for the separation of non-ferrous metals, the amount of aluminium potentially recoverable from bottom ashes is estimated in the range from 16,500 to 21,000 tonnes at the year 2015, and from 19,000 to 28,500 tonnes at 2020.  相似文献   
144.
The non-breeding movements of marine birds were poorly known until recently, but this information is essential to understanding the risk to different geographical populations from events on the wintering grounds. We tracked the migration routes and wintering areas of Thick-billed Murre Uria lomvia from two breeding colonies in eastern Canada: Coats Island in northern Hudson Bay and The Minarets, Baffin Island, during the period August 2007–May 2008 using geolocation loggers. Birds from The Minarets moved south rapidly post-breeding and wintered principally off Newfoundland and southern Labrador, or between Newfoundland and southern Greenland, remaining south of 55°N until at least the spring equinox. Those from Coats Island remained in Hudson Bay until at least mid-November, after which they moved rapidly through Hudson Strait to winter in southern Davis Strait and the northern Labrador Sea, mostly north of 55°N. Many individuals stayed throughout the winter in areas of heavy ice cover. Adults from the two colonies appear to be completely segregated in winter and those from Coats Island probably did not enter the area of the winter hunt in Newfoundland. Unexpectedly, some birds from The Minarets wintered in waters beyond the continental slope and outside the distribution of pack ice, demonstrating that particular individuals can be wholly pelagic throughout the winter. Coats Island birds returned through Hudson Strait as soon as open water areas became available in spring. Their sojourn in Hudson Bay coincided very closely with the occurrence of areas with <90% ice cover. In spite of the relatively large error in positions obtained from geolocation loggers, our results demonstrated the value of these devices by uncovering a number of previously unknown aspects of Thick-billed Murre non-breeding ecology in the Northwest Atlantic. Comparison of the non-breeding ecology based on SST experienced in winter show that the winter niche is broader than hitherto assumed, demonstrating that separate populations may experience different selection in the face of climate change.  相似文献   
145.
146.

Objectives

Motorcycle registrations have risen in recent years. Although motorcyclist crash fatalities in 2009 were 16% lower than in 2008, they were double the number of deaths in 1997. The present study examined current motorcyclists’ travel patterns and views of motorcycle helmets and other safety topics.

Methods

Motorcycle drivers were interviewed in a national telephone survey conducted in 2009. A weighted sample of 1,606 motorcyclists resulted from adjusting for the oversampling of those younger than 40 and those in the three states without a motorcycle helmet use law (Illinois, Iowa, New Hampshire). All analyses were based on the weighted sample, which was intended to result in a nationally representative sample of motorcyclists.

Results

About one-quarter of respondents said they did not always wear helmets. Of these respondents, 57% said a law requiring helmet use would persuade them to do so, and 27% said nothing would. Ninety-four percent of respondents in states with universal helmet laws said they always ride helmeted, compared with about half of respondents in other states. About half of all respondents favored these laws. About three-quarters said they believe helmets keep riders safer, including two-thirds of respondents who oppose universal laws and almost half of drivers who rarely/never wear helmets. Drivers ages 18–29 and drivers of sport/unclad sport, sport touring, and super sport motorcycles were more likely to always wear helmets, support universal helmet laws, and believe helmets keep riders safer. About half of respondents said antilock braking systems (ABS) enhance safety and that they would get ABS on their next motorcycle. Less than one-quarter thought an airbag would protect a motorcyclist in a crash, and even fewer would consider getting one on their next motorcycle. Forty-three percent of motorcyclists said they had crashed at least once; 62% of the most recent crashes involved no vehicles besides the motorcycle. Respondents reported riding their motorcycles about 5,400 miles, on average, during the past year. Drivers ages 18–29 reported riding fewer miles, on average, than older drivers and more often rode at night and to/from work or school. Drivers of touring and sport touring motorcycles traveled more miles and took more long trips.

Conclusions

Motorcyclists’ travel patterns and views vary widely, but there are distinct patterns by driver age and motorcycle type. Drivers who believe helmets keep riders safer are more likely to always wear them, but this belief appears insufficient to motivate some drivers to wear them. However, universal helmet laws appear effective in increasing helmet use. Many drivers are receptive to purchasing ABS on their next motorcycle.

Impact on industry

States should be encouraged to enact universal helmet laws, and motorcycle manufacturers should be encouraged to offer ABS.  相似文献   
147.
Polycyclic aromatic hydrocarbons (PAHs) are one of the main classes of contaminants in the terrestrial environment. Concentrations of biphenyl, fluorene, phenanthrene and pyrene were added to soil samples in order to investigate the anaerobic degradation potential of PAHs under denitrifying conditions. A mixed population of microorganisms obtained from a paddy soil was incubated for 20 days in anaerobic conditions in the presence of soil alone or with nitrate, adding, as electron donors, PAHs and, in some samples, glucose or acetate. At regular time intervals oxidation-reduction potential, PAHs concentration, microbial ATP and nitrate concentration into the solution were measured. Degradation trends for each hydrocarbon are similar under all conditions, indicating that the molecular conformation prevails over other parameters in controlling the degradation. Poor degradation results were obtained when PAHs were the only organic matter available for the inoculum, thus confirming the recalcitrance to degradation of these compounds. Biodegradation was influenced by the addition of other carbon sources. As better degradation results were generally obtained when acetate or glucose were added, the hypothesis of a co-metabolic enhancement of PAH biodegradation seems likely. Thus, anaerobic biodegradation of PAHs studied, biphenyl, fluorene, phenanthrene and pyrene, seems to be possible both through fermentative and respiratory metabolism, provided that low molecular weight co-metabolites and suitable electron acceptors (nitrate) are present.  相似文献   
148.
The allelopathic potential of oat (Avena sativa L., var. Argentina, Poaceae, Cyperales) was investigated under field and laboratory conditions. In field trials, oat plants provided an effective control of weeds, showing a species-specific impact: the most abundant weed species, Picris echioides was reduced by 94% in number of individuals. Aerial parts of oat plants, harvested immediately before soil incorporation, were utilized in a bioassay-guided isolation, which was aimed at identifying the phytotoxic compounds in a methanol/water extract of the aerial parts of the plants. Further partitions of extract gave an active n-butanol portion composed of flavonoids and saponins. Phytotoxic activity was detected for the flavonoid fraction, whereas no activity was found for the saponin mixture. Germination of an indicator species, lettuce (Lactuca sativa L.), was completely inhibited at flavonoid concentrations of 6.7, 10.0, and 20.0 mg/mL, and conversely the number of abnormal seedlings was greatly increased from 2% of control to over 96% at concentrations equal to 6.7 and 10.0 mg/mL. Analysis of the flavonoid fraction by ESI-MS techniques identified two components of the mixture as isoorientin 2-O-glucoside and isovitexin 2″-O-arabinoside. Saponins were characterized as avenacoside A, avenacoside B, 26-desglucoavenacoside A, and 26-desglucoavenacoside B. Both flavone C-glycosides and saponins were isolated previously from oat.  相似文献   
149.
ABSTRACT: Nutrient data from all available sources for the lower Mississippi River were examined for potential differences among sampling agencies and geographic locations for the period between 1960 and 1998. Monthly means grouped by parameter, sampling location and agency, were calculated and compared as paired sets, excluding those months where data were not available for both sets. Some significant differences were found between various agencies collecting nutrient data on the river, as well as between various stretches of river, especially in the case of phosphorus nutrient data. Results were used to synthesize data sets from which a history of nutrient loading in the Mississippi River was determined. General trends in nitrate+nitrite, total Kjeldahl nitrogen, orthophosphate, total phosphorus and silica loads, as well as changes in nutrient proportions and the specific limiting nutrient (by month) are reported. This study provides a useful summary of contemporary and historical nutrient data that may assist in the evaluation of Mississippi River water quality and its potential effect on the Gulf of Mexico.  相似文献   
150.
Hannan LB  Roth JD  Ehrhart LM  Weishampel JF 《Ecology》2007,88(4):1053-1058
Sea turtle nesting presents a potential pathway to subsidize nutrient-poor dune ecosystems, which provide the nesting habitat for sea turtles. To assess whether this positive feedback between dune plants and turtle nests exists, we measured N concentration and delta15N values in dune soils, leaves from a common dune plant (sea oats [Uniola paniculata]), and addled eggs of loggerhead (Caretta caretta) and green turtles (Chelonia mydas) across a nesting gradient (200-1050 nests/km) along a 40.5-km stretch of beach in east central Florida, USA. The delta15N levels were higher in loggerhead than green turtle eggs, denoting the higher trophic level of loggerhead turtles. Soil N concentration and delta15N values were both positively correlated to turtle nest density. Sea oat leaf tissue delta15N was also positively correlated to nest density, indicating an increased use of augmented marine-based nutrient sources. Foliar N concentration was correlated with delta15N, suggesting that increased nutrient availability from this biogenic vector may enhance the vigor of dune vegetation, promoting dune stabilization and preserving sea turtle nesting habitat.  相似文献   
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