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111.
Franco Andreone Gonçalo M. Rosa Jean Noël Angelica Crottini Miguel Vences Christopher J. Raxworthy 《Die Naturwissenschaften》2010,97(6):525-543
We describe a new mantelline frog of the genus Blommersia found in rainforest in North East Madagascar, from the protected areas of Ambatovaky, Betampona, Masoala, and Zahamena. Blommersia angolafa n.sp. is a small frog, with a body size of 17–21 mm, expanded finger and toe tips, and colouration ranging from yellow to
dark brown, with pale-bluish spots on the flanks and light tips of fingers and toes. A peculiar aspect characterising this
new species is its novel life history and reproductive mode. Both sexes live and breed in a phytotelmic habitat of water accumulated
within fallen prophylls and fallen leaf sheaths of at least three species of Dypsis palms. Within these phytotelmata, egg laying and complete larval development occur. Thus, B. angolafa n.sp. represents a new evolutionary lineage of Malagasy frogs in which phytotelmy is known. Up to now, reproduction in phytotelmata
in Malagasy frogs has been reported for many cophyline microhylids, most species of Guibemantis, Mantella laevigata, and possibly in a still-undescribed species belonging to the genus Spinomantis. We consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of
lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding
strategy. The new species, being specialised to a habitat represented by a few selected Dypsis species, potentially suffers the selective exploitation of these palms. 相似文献
112.
H.P. Jarvie P.J.A. Withers M.J. Bowes E.J. Palmer-Felgate D.M. Harper K. Wasiak P. Wasiak R.A. Hodgkinson A. Bates C. Stoate M. Neal H.D. Wickham S.A. Harman L.K. Armstrong 《Agriculture, ecosystems & environment》2010,135(4):238-252
This paper provides an overview of the impacts of rural land use on lowland streamwater phosphorus (P) and nitrogen (N) concentrations and P loads and sources in lowland streams. Based on weekly water quality monitoring, the impacts of agriculture on streamwater P and N hydrochemistry were examined along a gradient of rural–agricultural land use, by monitoring three sets of ‘paired’ (near-adjacent) rural headwater streams, draining catchments which are representative of the major geology, soil types and rural/agricultural land use types of large areas of lowland Britain. The magnitude and timing of P and N inputs were assessed and the load apportionment model (LAM) was applied to quantify ‘continuous’ (point) source and ‘flow-dependent’ (diffuse) source contributions of P to these headwater streams. The results show that intensive arable farming had only a comparatively small impact on streamwater total phosphorus (TP loads), with highly consistent stream diffuse-source TP yields of ca. 0.5 kg-P ha?1 year?1 for the predominantly arable catchments with both clay and loam soils, compared with 0.4 kg-P ha?1 year?1 for low agricultural intensity grassland/woodland on similar soil types. In contrast, intensive livestock farming on heavy clay soils resulted in dramatically higher stream diffuse-source TP yields of 2 kg-P ha?1 year?1. The streamwater hydrochemistry of the livestock-dominated catchment was characterised by high concentrations of organic P, C and N fractions, associated with manure and slurry sources. Across the study sites, the impacts of human settlement were clearly identifiable with effluent inputs from septic tanks and sewage treatment works resulting in large-scale increases in soluble reactive phosphorus (SRP) loads and concentrations. At sites heavily impacted by rural settlements, SRP concentrations under baseflow conditions reached several hundred μg-P L?1. Load apportionment modelling demonstrated significant ‘point-source’ P inputs to the streams even where there were no sewage treatment works within the upstream catchment. This indicates that, even in sparsely populated rural headwater catchments, small settlements and even isolated groups of houses are sufficient to cause significant nutrient pollution and that septic tank systems serving these rural communities are actually operating as multiple point sources, rather than a diffuse input. 相似文献
113.
The carbon budget of California 总被引:1,自引:0,他引:1
Christopher Potter 《Environmental Science & Policy》2010,13(5):373-383
The carbon budget of a region can be defined as the sum of annual fluxes of carbon dioxide (CO2) and methane (CH4) greenhouse gases (GHGs) into and out of the regional surface coverage area. According to the state government's recent inventory, California's carbon budget is presently dominated by 115 MMTCE per year in fossil fuel emissions of CO2 (>85% of total annual GHG emissions) to meet energy and transportation requirements. Other notable (non-ecosystem) sources of carbon GHG emissions in 2004 were from cement- and lime-making industries (7%), livestock-based agriculture (5%), and waste treatment activities (2%). The NASA-CASA (Carnegie Ames Stanford Approach) simulation model based on satellite observations of monthly vegetation cover (including those from the Moderate Resolution Imaging Spectroradiometer, MODIS) was used to estimate net ecosystem fluxes and vegetation biomass production over the period 1990–2004. California's annual NPP for all ecosystems in the early 2000s (estimated by CASA at 120 MMTCE per year) was roughly equivalent to its annual fossil fuel emission rates for carbon. However, since natural ecosystems can accumulate only a small fraction of this annual NPP total in long-term storage pools, the net ecosystem sink flux for atmospheric carbon across the state was estimated at a maximum rate of about 24 MMTCE per year under favorable precipitation conditions. Under less favorable precipitation conditions, such as those experienced during the early 1990s, ecosystems statewide were estimated to have lost nearly 15 MMTCE per year to the atmosphere. Considering the large amounts of carbon estimated by CASA to be stored in forests, shrublands, and rangelands across the state, the importance of protection of the natural NPP capacity of California ecosystems cannot be overemphasized. 相似文献
114.
These Notes from the Field summarise the governance guidelines developed by the International Risk Governance Council (IRGC) to address the key challenges that policy-makers face when designing and implementing policies and regulations for the increasing production, trade and use of bioenergy.The guidelines comprise an integrated and coherent set of policy recommendations and practical actions to help policy-makers and industry account for the various trade-offs presented by bioenergy and develop sustainable bioenergy production for domestic use and international trade. They include land-use policies, full life-cycle assessments, as well as sustainability standards and certification criteria. 相似文献
115.
Regan Lyon Christopher Lyon Helen Markowski Sara L. Boltinhouse 《Traffic injury prevention》2016,17(2):109-113
Objective: Outcomes from previous studies report the driving under the influence (DUI) conviction rates for trauma patients in several cities within Canada and the United States over the last 2 decades. This study reports charge, conviction, and prosecution rates for trauma patients at 2 level I trauma centers servicing a large metropolitan city.
Methods: A retrospective review of the trauma databases was completed to identify patients meeting inclusion criteria. Four hundred sixty patients were identified and their records were compared with the district attorney's records for DUI charges and convictions.
Results: The conviction rate for this study was 8.7%, demonstrating continued low rates of conviction despite growing interest and public awareness of drinking and driving.
Conclusions: We discuss legal considerations that providers should consider when treating patients who have been drinking and driving. 相似文献
116.
117.
Scott W. Stine Inhong Song Christopher Y. Choi Charles P. Gerba 《Food and environmental virology》2011,3(2):86-91
The purpose of this study was to quantify the transfer of viral and bacterial pathogens in water used to dilute pesticides
sprayed onto the surfaces of cantaloupe, iceberg lettuce, and bell peppers. The average percent transfer of bacteria was estimated
to range from 0.00021 to 9.4%, while average viral transfer ranged from 0.055 to 4.2%, depending on the type of produce. Based
on these values the concentrations of hepatitis A virus (HAV) and Salmonella in water necessary to achieve a 1:10,000 annual risk of infection were calculated. Under worst case scenario assumptions,
in which a pesticide is applied on the same day that the produce is harvested and when maximum transfer values are used, concentrations
of 1.5 × 10−3 CFU Salmonella or 2.7 × 10−7 MPN HAV per 100 ml of the water used for application would result in 1:10,000 annual infection risk to anyone who consumes
the fresh produce. If harvesting does not occur until at least 14 days after the application, to produce the same risk of
infection, the numbers of Salmonella in 100 ml of water used to dilute the pesticides will be greater by up to five orders of magnitude, while the HAV numbers
will have increased by up to two orders of magnitude. Based on the reported concentrations of enteric viruses in surface and
ground waters in the United States, a 1:10,000 annual risk of infection could easily be exceeded with some groundwater sources
used in the United States. To reduce the risks associated with the consumption of fresh produce, water used to prepare pesticides
in spray applications should be evaluated for its microbiological quality. 相似文献
118.
Arthur J. Caplan Christopher J. Ellis Emilson C.D. Silva 《Journal of Environmental Economics and Management》1999,37(3):256
In this paper, global warming is an asymmetric transboundary externality which benefits some countries or regions and harms others. We use a simple two-country model to analyze the effects of global warming on resource allocations, the global-warming stock, and national and global welfare. 相似文献
119.
Using a multilevel framework, we hypothesized that both employee perceptions of procedural justice and a work unit level measure of procedural justice context would be associated with employee reports of job satisfaction and organizational commitment. Three hundred and twenty-three employees from 53 branches of a financial services organization were used to test this hypothesis. Hierarchical linear modeling analyses revealed that procedural justice context explained variance in employee job satisfaction beyond that accounted for by individual perceptions of procedural justice. With regard to organizational commitment, this hypothesis was not supported. The results are discussed in connection with contextual aspects of procedural justice. © 1998 John Wiley & Sons, Ltd. 相似文献
120.
A great number of pedestrians are killed or injured in traffic crashes every year in the US. Vehicle crashes involving pedestrians are often more severe than other crashes because pedestrians are unprotected and are hence more likely to suffer injuries or death if struck by a motor vehicle. To improve pedestrian safety, a variety of treatments such as overhead flashing beacons, in-street crossing signs, in-roadway warning lights, and traffic calming measures have been used. One treatment, in-street yield-to-pedestrian channelizing devices (YTPCD), has been used in many states, including Pennsylvania, where approximately 10% of traffic crash fatalities are pedestrians each year.In an effort to improve pedestrian safety, the Pennsylvania Department of Transportation (PennDOT) has widely deployed YTPCD. This study examines the spillover (indirect) effects of such devices on motorist and pedestrian behavior. With data collected from eight sites that did not have but were in the vicinity of YTPCD implementations, analysis results show that such devices have significantly positive spillover effects on pedestrian safety at intersections, but they tend to have negative spillover effects at mid-block locations. Overall, the YTPCD appear to have a positive impact on changing motorist and pedestrian behavior, and merit consideration for future usage of this type of device. 相似文献