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81.
A. Cole Burton David Huggard Erin Bayne Jim Schieck Péter Sólymos Tyler Muhly Dan Farr Stan Boutin 《Environmental monitoring and assessment》2014,186(6):3605-3617
Effective ecological monitoring is imperative in a human-dominated world, as our ability to manage functioning ecosystems will depend on understanding biodiversity responses to anthropogenic impacts. Yet, most monitoring efforts have either been narrowly focused on particular sites, species and stressors — thus inadequately considering the cumulative effects of multiple, interacting impacts at scales of management relevance — or too unfocused to provide specific guidance. We propose a cumulative effects monitoring framework that integrates multi-scaled surveillance of trends in biodiversity and land cover with targeted evaluation of hypothesized drivers of change. The framework is grounded in a flexible conceptual model and uses monitoring to generate and test empirical models that relate the status of diverse taxonomic groups to the nature and extent of human “footprint” and other landscape attributes. An adaptive cycle of standardized sampling, model development, and model evaluation provides a means to learn about the system and guide management. Additional benefits of the framework include standardized data on status and trend for a wide variety of biodiversity elements, spatially explicit models for regional planning and scenario evaluation, and identification of knowledge gaps for complementary research. We describe efforts to implement the framework in Alberta, Canada, through the Alberta Biodiversity Monitoring Institute, and identify key challenges to be addressed. 相似文献
82.
83.
Xinhua Fu V. Benno Meyer-Rochow John Tyler Hirobumi Suzuki Raphael De Cock 《Chemoecology》2009,19(3):155-168
Larval defensive behaviour and eversible organ morphology were compared in the firefly species Luciola cruciata Motschulsky 1854, L. lateralis Motschulsky 1860, L. leii Fu et Ballantyne 2006, Lampyris noctiluca Linnaeus 1767, Pyrocoelia analis Fabricius 1801, P. pectoralis Oliver 1883, P. sp. and two Diaphanes species. In all cases the eversible organs are located on the pleural cuticle, dorsal to the spiracle, but there is considerable
variation between species in their number, size and shape. In La. noctiluca they are confined to the abdomen, whereas in the other species they also occur on the meta- and mesothorax. In La. noctiluca and the Pyrocoelia species the organs are columnar in shape, contrasting with the forked organs of the Luciola and Diaphanes species. The eversible organs of the Luciola species, which are all aquatic, are remarkably larger (relative to body length) than those of the other, terrestrial species.
On organ eversion the Luciola species emit an odour resembling pine oil, the Diaphanes species smell weakly of mint and L. noctiluca and the Pyrocoelia species produce no discernible scent, though ants are nonetheless repelled by contact with everted L. noctiluca organs. The organs of all the species studied support protuberances on their external surface, though these too vary in shape,
size and ornamentation between species. In all species except L. noctiluca each protuberance is connected to a well-developed globular body via a long, thick stalk. Circular foveae are located in
the centres of these globular bodies. The globular bodies consist of secretory cells characterized by the presence of numerous
mitochondria and an extensive system of cisternae and tubular endoplasmic reticulum. Behavioural tests revealed that small
larvae run away instead of becoming immobile and glowing, whereas large larvae start to glow when disturbed. The study shows
that the eversible larval organs form an important part of a defensive arsenal in the Lampyridae. 相似文献
84.
The ultrastructural features of gametogenesis are described in male and female colonies of the sea pen Pennatula aculeata. Specimens were collected for observation and fixation at 113 to 231 m depth in the Gulf of Maine, USA, in August 1993. The
species is gonochoric, and all stages of gametogenesis are observed in both male and female colonies >45 mm in height. Gametogenesis
shows several features that differ from sea anemones. The developing oocytes and sperm cysts are completely encompassed by
gastrodermally derived follicle cells, and they are released from the mesenteries into the coelenteron before they are fully
differentiated. Following maturation in the coelenteron, the eggs and intact sperm cysts are expelled through the mouths of
the autozoids during spawning. The expulsion of sperm cysts suggests that they function as primitive spermatophores, perhaps
as a way of reducing sperm dilution. Vitellogenesis results in the biosynthesis of lipid droplets which are the sole nutrient
reserves in the egg. Heterosynthetic vitellogenesis is characterized by the importation of lipid precursors into the oocyte,
and there is some indirect evidence that hypertrophic follicle cells play a role in production, transport, and/or mediation
of these precursors. Spermatogenesis is similar to that of other anthozoans. The spermatozoon has a cone-shaped head, a posterior
nuclear fossa, a ring of lipid-like bodies in the midpiece, a prominent cytoplasmic collar surrounding the proximal flagellum,
and a single mitochondrion, but the posterior region of the sperm also contains previously undescribed concentric rings of
cisternae resembling smooth endoplasmic reticulum.
Received: 23 March 1998 / Accepted: 31 July 1998 相似文献
85.
John M. Tyler Lloyd V. Hinton John G. Olin 《Journal of the Air & Waste Management Association (1995)》2013,63(2):130-135
In the near future the State of Minnesota will adopt noise pollution standards and regulations based on the findings presented in this paper. Comprehensive noise standards are presented for all sources of noise, including airports, highways, and industrial sources. Two of the three dimensions of noise—intensity and frequency—are measured by the use of the unit dBA, whereas the third dimension—duration—is measured by use of the temporal distribution, expressed as Lx, where x is the sound pressure level in dBA exceeded x% of the time. Standards are established for five zones: 1. residential—single family, 2. residential— apartments, public buildings, 3. commercial, 4. manufacturing, and 5 industrial. The Lx standards apply to most noises including industrial and highway noises. Aircraft noise and impulse noise standards are also discussed. The six phase implementation plan for noise abatement is discussed. 相似文献
86.
We examine in detail trends from 1966 to 1990 and the fitting of statistical models to assess whether significant changes have taken place in casualty rates since local bus deregulation in 1986.The major source of data is the ‘Stats 19’ collated from police reports by the Department of Transport.The evidence indicates that no significant change in casualty rates for bus and coach occupants (defined as those killed or seriously injured) has occurred since local bus deregulation, although the previous trend of reduction in fatality rates has not been maintained.International comparisons have been made between Britain and a sample of other West European countries. Britain appears to have a higher occupant fatality rate. However, other countries′ data do not always include casualties to bus and coach occupants other than those in which vehicular collisions occur. Better comparative data is available for accidents involving buses and coaches with other road users, notably for Britain and Germany. These suggest that such accidents tend to reflect the national pattern of road casualty rates — for example, Germany has a higher level of collisions between buses and coaches, and other road vehicles, while Britain has a relatively high incidence of casualties involving pedestrians.Differences in accident rates between Britain and other European countries and the extent to which they reflect real differences, as distinct from those due to differences in recording of data, are evaluated, along with policy implications. 相似文献
87.
PROBLEM: Eye injury is currently a leading cause of visual impairment and monocular blindness in the United States. Information regarding consumer products associated with eye injuries can have important implications for the prevention of these injuries. METHODS: The National Electronic Injury Surveillance System (NEISS) was used to describe the types of consumer products associated with emergency department treated eye injuries in the United States from 1998 through 2002. RESULTS: The leading product type associated with eye injuries was welding equipment followed by household cleaners, basketball equipment, workshop equipment, and adhesives. Eye injuries attributed to hardware, tools, construction, sports, toys, and lawn equipment were more common among males. In females, eye injuries attributable to chemicals, housewares, storage and organization, and bed and bath items were more common. Differences were also apparent across the age spectrum. CONCLUSION: This study identified specific products and categories of products frequently associated with eye injury and prevention initiatives should focus on these items. IMPACT ON INDUSTRY: This study has identified consumer products associated with eye injuries requiring medical treatment in the United States. Manufacturers of these products could be encouraged to add or strengthen safety messages regarding the potential for eye injury. 相似文献
88.
Wagner T Soranno PA Cheruvelil KS Renwick WH Webster KE Vaux P Abbitt RJ 《Environmental monitoring and assessment》2008,141(1-3):131-147
We quantified potential biases associated with lakes monitored using non-probability based sampling by six state agencies in the USA (Michigan, Wisconsin, Iowa, Ohio, Maine, and New Hampshire). To identify biases, we compared state-monitored lakes to a census population of lakes derived from the National Hydrography Dataset. We then estimated the probability of lakes being sampled using generalized linear mixed models. Our two research questions were: (1) are there systematic differences in lake area and land use/land cover (LULC) surrounding lakes monitored by state agencies when compared to the entire population of lakes? and (2) after controlling for the effects of lake size, does the probability of sampling vary depending on the surrounding LULC features? We examined the biases associated with surrounding LULC because of the established links between LULC and lake water quality. For all states, we found that larger lakes had a higher probability of being sampled compared to smaller lakes. Significant interactions between lake size and LULC prohibit us from drawing conclusions about the main effects of LULC; however, in general lakes that are most likely to be sampled have either high urban use, high agricultural use, high forest cover, or low wetland cover. Our analyses support the assertion that data derived from non-probability-based surveys must be used with caution when attempting to make generalizations to the entire population of interest, and that probability-based surveys are needed to ensure unbiased, accurate estimates of lake status and trends at regional to national scales. 相似文献
89.
The non-indigenous green crab (Carcinus maenas) is an important predator on bivalve wild beds in coastal areas worldwide. This study explored size-dependent green crab
prey preference on American oysters (Crassostrea virginica), blue mussels (Mytilus edulis), and soft-shell clams (Mya arenaria) in a productive coastal system of Atlantic Canada. Using two sizes of prey and three different experimental manipulations,
small, medium, and large green crabs were given a choice among these three bivalves, and their daily feeding rates were monitored
over the course of 3 days. For both prey sizes, green crabs showed an early feeding preference for soft-shell clams and, only
as they declined in numbers, a switch toward mussels and subsequently toward oysters. We found that such changes in the timing
(order) of prey preference are related to prey differences in shell thickness, a fairly reliable indicator of prey shell strength. 相似文献
90.
Heather A. Holmes Eric R. Pardyjak Bonnie J. Tyler Richard E. Peterson 《Atmospheric environment (Oxford, England : 1994)》2009,43(28):4348-4358
An interdisciplinary field study designed to investigate the spatial and temporal variability of atmospheric aerosols during high particulate matter (PM) events along the US–Mexico border near Yuma, AZ was run during the week of March 18, 2007. The experiments were designed to quantify chemical composition and physical phenomena governing the transport of aerosols generated from episodic high PM events. The field study included two micrometeorological monitoring sites; one rural and one urban, equipped with sonic anemometers, continuous particulate concentration monitors and ambient aerosol collection equipment. In addition to the two main monitoring sites, five additional locations were equipped with optical particle counters to allow for the investigation of the spatial and temporal distribution of PM2.5 in the urban environment. In this paper, the meteorological and turbulence parameters governing the distribution and concentration of PM2.5 in the urban environment for two high-wind erosion events and one burning event are compared. The interaction between local atmospheric conditions and the particulate distribution is investigated. Results indicate that a single point measurement in the urban area of Yuma may not be sufficient for determining the ambient PM concentrations that the local population experiences; all three high PM events indicated PM2.5 varied considerably with maximum urban concentrations 5–10 times greater than the measured minima. A comparison of inorganic and carbonaceous content of the aerosols for the three high PM events is presented. The comparison shows an increase in silicon during crustal dust events and an increase in elemental and organic carbon during the burn event. Additional surface chemistry analysis, using time-of-flight secondary ion mass spectrometry (ToF-SIMS), for aerosols collected at the urban and rural sites during the burn event are discussed. The surface chemistry analysis provides positive ion mass spectra of organic and inorganic species in the ambient aerosol, and can be used to determine the type of combustion process that contributed to an increase in PM concentration during the burn event. 相似文献