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71.
72.
Maartje J. Klapwijk Anna J. M. Hopkins Louise Eriksson Maria Pettersson Martin Schroeder Åke Lindelöw Jonas Rönnberg E. Carina H. Keskitalo Marc Kenis 《Ambio》2016,45(2):223-234
Intensifying global trade will result in increased numbers of plant pest and pathogen species inadvertently being transported along with cargo. This paper examines current mechanisms for prevention and management of potential introductions of forest insect pests and pathogens in the European Union (EU). Current European legislation has not been found sufficient in preventing invasion, establishment and spread of pest and pathogen species within the EU. Costs associated with future invasions are difficult to estimate but past invasions have led to negative economic impacts in the invaded country. The challenge is combining free trade and free movement of products (within the EU) with protection against invasive pests and pathogens. Public awareness may mobilise the public for prevention and detection of potential invasions and, simultaneously, increase support for eradication and control measures. We recommend focus on commodities in addition to pathways, an approach within the EU using a centralised response unit and, critically, to engage the general public in the battle against establishment and spread of these harmful pests and pathogens. 相似文献
73.
Maeva Giraudo Audrey Bruneau Andrée D. Gendron Philippe Brodeur Martin Pilote David J. Marcogliese Christian Gagnon Magali Houde 《Environmental science and pollution research international》2016,23(18):18073-18084
A multi-disciplinary approach was used to evaluate the health of yellow perch (Perca flavescens) in the St. Lawrence River (Quebec, Canada), which is experiencing a severe population decline in the downstream portion of the river. Physiological parameters, liver alterations, trace metal concentrations, parasite prevalence and abundance, stable isotope composition, and the presence/absence of the viral hemorragic septicemia virus (VHSV) were evaluated in perch collected at six sites along the river: Lake St. François, Lake St. Louis (north and south), Beauregard Island, and Lake St. Pierre (north and south). Trace metal concentrations in surface water were higher in Lake St. Louis and downstream of a major urban wastewater treatment plant discharge, indicating that this effluent was a significant source of Cu, As, Ag, Zn, and Cd. Levels of Pb in surface water exceeded thresholds for the protection of aquatic life in Lake St. Louis and were negatively correlated with body condition index in this lake. In Lake St. Pierre, Cu, Ag, and Cd bioaccumulated significantly in perch liver and lower body condition index and greater liver damage were observed compared to upstream sites. Parasite analyses indicated a higher abundance of metacercariae of the trematodes Apophallus brevis and Diplostomum spp. in Lake St. Louis, and VHSV was not detected in the liver of yellow perch for all studied sites. Overall, results suggested that the global health of yellow perch from Lake St. Pierre is lower compared to upstream studied sites, which could contribute to the documented population collapse at this site. 相似文献
74.
Climate change generally requires species to migrate northward or to higher elevation to maintain constant climate conditions, but migration requirement and migration capacity of individual species can vary greatly. Individual populations of species occupy different positions in the landscape that determine their required range shift to maintain similar climate, and likewise the migration capacity depends on habitat connectivity. Here, we demonstrate an approach to quantifying species vulnerabilities to climate change for 419 rare vascular plants in Alberta, Canada, based on a multivariate velocity of climate change metric, local habitat fragmentation, and migration capacity. Climate change velocities indicated that future migration requirements ranged from 1 to 5 km/year in topographically complex landscapes, such as the Alberta Foothills and Rocky Mountains. In contrast, migration requirements to maintain constant climate in relatively flat Boreal Plains, Parkland, and Grassland ranged from 4 to 8 km/year. Habitat fragmentation was also highest in these flat regions, particularly the Parkland Natural Region. Of the 419 rare vascular plants assessed, 36 were globally threatened (G1–G3 ranking). Three globally threatened species were ranked as extremely vulnerable and five species as highly vulnerable to the interactions among climate change velocity, habitat fragmentation, and migration capacity. Incorporating dispersal characteristics and habitat fragmentation with local patterns in climate change velocity improves the assessment of climate change threats to species and may be applied to guide monitoring efforts or conservation actions. 相似文献
75.
Claire L. Martin Ian D. Longley James R. Dorsey Rick M. Thomas Martin W. Gallagher Eiko Nemitz 《Atmospheric environment (Oxford, England : 1994)》2009,43(31):4714-4721
Little information is known about the behaviour of ultrafine particles (UFP) on a citywide scale. Total particle number flux, dominated by UFP, and other meteorological parameters were collected from tower sites in Manchester, London, Edinburgh and Gothenburg between 1999 and 2006 using the eddy covariance technique. Averaged diurnal cycles were produced for particle number flux, concentration, sensible heat flux, emission velocity, friction velocity, wind speed and temperature. UFP flux cycles showed clear diurnal trends which were linked to traffic activity and local sources. Wind sector analysis showed contributions to flux from local heavily urbanised areas. A simple parameterised model linking UFP flux to traffic activity, sensible heat and friction velocity above the city was produced. 相似文献
76.
Elizabeth A. Stone Curtis J. Hedman Rebecca J. Sheesley Martin M. Shafer James J. Schauer 《Atmospheric environment (Oxford, England : 1994)》2009,43(27):4205-4213
The high-molecular weight water-soluble organic compounds present in atmospheric aerosols underwent functional-group characterization using liquid chromatography tandem mass spectrometry (LC-MS/MS), with a focus on understanding the chemical structure and origins of humic-like substances (HULIS) in the atmosphere. Aerosol samples were obtained from several locations in North America at times when primary sources contributing to organic aerosol were well-characterized: Riverside, CA, Fresno, CA, urban and peripheral Mexico City, Atlanta, GA, and Bondville, IL. Chemical analysis targeted identification and quantification of functional groups, such as aliphatic, aromatic, and bulk carboxylic acids, organosulfates, and carbohydrate-like substances that comprise species with molecular weights (MW) 200–600 amu. Measured high-MW functional groups were compared to modeled primary sources with the purpose of identifying associations between aerosol sources, high-MW aerosol species, and HULIS. Mobile source emissions were linked to high-molecular weight carboxylic acids, especially aromatic acids, biomass burning was associated with carboxylic acids and carbohydrate-like substances, and secondary organic aerosol (SOA) correlated well with the total amount of HULIS measured, whereas organosulfates showed no correlation with aerosol sources and exhibited unique spatial trends. These results suggested the importance of motor vehicles, biomass burning, and SOA as important sources of precursors to HULIS. Structural characteristics of atmospheric HULIS were compared to terrestrial humic and fulvic acids and revealed striking similarities in chemical structure, with the exception of organosulfates which were unique to atmospheric HULIS. 相似文献
77.
Ecological disturbances of forests by insects have a complex array of associated human dimensions presenting complications
for natural resource decision making and relationships between stakeholders and managers. This article discusses the human
context of forest disturbances by insects by reviewing four cases of bark beetle forest disturbance from British Columbia
in Canada, Bavarian Forest National Park in Germany, the Kenai Peninsula in Alaska, and the north central region of Colorado.
Findings and lessons learned from these studies are outlined along with their implications for managing forest disturbances
by insects in general. Conclusions focus on the need to assess the broad array of impacts and risks perceived by local residents
and the capacity for local action and involvement in managing forest disturbances. Communication and interaction between resource
managers and local stakeholders can facilitate the identification of management priorities and potentially reduce some of
the risks associated with forest disturbances by insects. 相似文献
78.
An indispensable asset at risk: merits and needs of chemicals-related environmental sciences 总被引:1,自引:1,他引:0
79.
T.J. Wallington M.D. Hurley O.J. Nielsen 《Atmospheric environment (Oxford, England : 1994)》2009,43(27):4247-4249
The infrared spectrum of HCF2OCF2OCF2CF2OCF2H (CAS# 188690-77-9) has been re-measured. The integrated absorption intensity over the range 1000–1500 cm?1 measured in the present work is (6.65 ± 0.33) × 10?17 cm2 molecule?1 cm?1 in 700 Torr of air at 296 K. The radiative efficiency of HCF2OCF2OCF2CF2OCF2H is calculated to be 1.02 W m?2 ppb?1. The value reported in the 2007 Intergovernmental Panel on Climate Change (IPCC) report is approximately 35% larger reflecting what we believe to be an erroneously high value for the absorption strength of HCF2OCF2OCF2CF2OCF2H adopted by the IPCC. 相似文献
80.
Martin D. Robards John J. Burns Chanda L. Meek Annette Watson 《Journal of environmental management》2009,91(1):57-66
Decision rules are the agreed-upon points at which specific management interventions are initiated. For marine mammal management under the U.S. Marine Mammal Protection Act (MMPA), decision rules are usually based on either a numeric population or biological-removal approach. However, for walrus and other ice-associated pinnipeds, the inability to reliably assess population numbers or biological removals highlights a significant gap in the MMPA, particularly when the Arctic environment is rapidly changing. We describe the MMPA's ecosystem-based management goals, and why managers have bypassed these goals in favor of an approach that depends upon numerical population assessment. We then revisit the statute's primary goals in light of current knowledge about the Pacific walrus ecosystem and new developments in environmental governance. We argue that to monitor and respond to changes in the walrus ecosystem, decision rules should be based on scientific criteria that depend less on the currently-impractical goal of accurately enumerating population size and trends, or removals from that population. Rather, managers should base decisions on ecological needs and observed ecological changes. To implement this approach would require an amendment to the MMPA that supports filling the gap in management with achievable decision rules. Alternatively, walrus and other ice-associated pinnipeds will remain largely unmanaged during a period of profound environmental change. 相似文献