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M. L. Mallory A. J. Gaston M. R. Forbes H. G. Gilchrist B. Cheney S. Lewis P. M. Thompson 《Marine Biology》2008,154(6):1031-1040
Variation in the timing and abundance of marine food resources is known to affect the breeding behaviour of many seabirds,
constraining our understanding of the extent to which these behaviours vary in different parts of a species’ range. We studied
incubation shifts of northern fulmars (Fulmarus glacialis) breeding at two colonies in Arctic Canada (High Arctic oceanographic zone) and one colony in the UK (Boreal oceanographic
zone) between 2001 and 2005. Fulmars in Arctic Canada had longer incubation shifts than previously reported at more southern
colonies, presumably because marine productivity is lower early in the breeding season in the Arctic. Shift durations were
particularly long at one colony in years with abnormally late, extensive sea-ice cover, although at the other Arctic colony,
where sea-ice cover is predictably late every year, the duration of shifts was shorter than expected. At the Boreal colony,
incubation shifts were much longer than expected, similar to Arctic colonies, and likely attributable to poor marine food
supplies in the North Sea in recent years. Collectively, our data suggest that fulmars can adjust their incubation rhythm
to compensate for poor marine feeding conditions, although this may incur a cost to body condition or reproductive success. 相似文献
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Ferchichi Karima Amdouni Noureddine Chevalier Yves Hbaieb Souhaira 《Environmental science and pollution research international》2022,29(55):83112-83125
Environmental Science and Pollution Research - The presence of antibiotics as micro-contaminants in the water and aqueous environments is a health concern to humans and the ecosystem. Therefore,... 相似文献
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J.?Orestes?CerdeiraEmail author Kevin?J.?Gaston Leonor?S.?Pinto 《Environmental Modeling and Assessment》2005,10(3):183-192
The spatial relations of sites within networks of priority areas for conservation is critical to the long-term maintenance
of key genetic, population and ecosystem processes. However, these relations have received relatively little attention in
the development of mathematical methods for objectively identifying such networks. Here we present a novel heuristic for incorporating
connectivity explicitly as part of the model constraints, provide an integer linear programming formulation for the same problem,
describe an integer cutting procedure which defines a sequence of non-decreasing lower bounds on the optimal solution and
report the results of some computational experiments using these algorithms. 相似文献
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Domestic gardens make substantial contributions to the provision of green space in urban areas. However, the ecological functions provided by such gardens depend critically on their configuration and composition. Here, we present the first detailed analysis of variation in the composition of urban gardens, in relation to housing characteristics and the nature of the surrounding landscape, across different cities in the United Kingdom. In all five cities studied (Belfast, Cardiff, Edinburgh, Leicester, and Oxford), garden size had an overwhelming influence on garden composition. Larger gardens supported more of the land-use types recorded, in greater extents, and were more likely to contain particular features, including tall trees and mature shrubs, areas of unmown grass and uncultivated land, vegetable patches, ponds, and composting sites. The proportional contribution of non-vegetated land-uses decreased as garden area increased. House age was less significant in determining the land-use within gardens, although older houses, which were more likely to be found further from the urban edge of the city, contained fewer hedges and greater areas of vegetation canopy >2 m in height. Current UK government planning recommendations will ultimately reduce the area of individual gardens and are thus predicted to result in fewer tall trees and, in particular, less vegetation canopy >2 m. This might be detrimental from ecological, aesthetic, social, and economic stand points. 相似文献
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Burwell RW Beasley JS Gaston LA Borst SM Sheffield RE Strahan RE Munshaw GC 《Journal of environmental quality》2011,40(4):1241-1248
Nutrient and sediment runoff from newly constructed levee embankments pose a threat to water quality during soft armor vegetation establishment. Research was initiated in 2008 and 2009 to evaluate the effect of bermudagrass ( L.) coverage and N source on nutrient and sediment runoff from levee embankments during establishment. Bermudagrass plots were seeded at 195.3 kg pure live seed ha and fertilized at 50 kg N ha using a water-soluble N source, urea or NH-NO, or slow-release N source, S-coated urea (SCU) or urea formaldehyde (UF), with controls unfertilized. Vegetative cover percentage, time until the onset of runoff, runoff volume, and total solids (TS), NO-N, and NH-N concentrations were measured from simulated and natural rainfall events for 70 d in 2008 and 56 d in 2009. Bermudagrass at 90% grass cover delayed the onset of runoff an additional 441 to 538 s and reduced runoff volumes 74 to 84% of that exhibited at 10% grass cover. Nitrogen fertilizers did not accelerate bermudagrass growth sufficiently, however, to reduce TS loading compared with unfertilized bermudagrass in either year of the study. The application of urea and SCU resulted in cumulative N losses of 2.45 and 3.13 kg ha compared with 1.59 kg ha from the unfertilized bermudagrass in 2008, and 1.73 kg ha from NH-NO vs. 0.24 kg ha from controls in 2009. Only UF increased bermudagrass establishment without increasing cumulative N losses compared with unfertilized bermudagrass. Therefore, the benefit of greater erosion and runoff resistance expected from N-accelerated vegetative growth did not occur but had the unintended consequence of higher N losses when water-soluble N and SCU fertilizers were applied. 相似文献
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Long-term application of poultry (Gallus gallus domesticus) litter has built high levels of P in certain Coastal Plain soils of north Louisiana. However, soil P/runoff P relationships for soil and environmental conditions of the area have not been examined. This study measured soil P (total, Bray 1, Bray 2, Mehlich 3, resin-exchangeable, and water-extractable) and runoff P (dissolved P, DP; and total P, TP) at four pasture sites previously amended with poultry litter. Sites varied in soil P due to annual litter applications ranging from 1 to more than 20. Three replicated plots at each site were subjected to simulated rainfalls over 2 yr, and concentrations of DP and TP in runoff were measured and related to soil P. This allowed examination of soil P/runoff P relationships and their changes over time. Runoff DP was also related to DP desorbed from surface soil in a miscible displacement experiment. Among measures of soil P, only resin-exchangeable and water-extractable P showed significant decreases over 2 yr. These measures of soil P explained 54 to 64% of the variability in runoff DP data. However, the miscible displacement technique proved the best indicator of runoff DP, explaining 70% of the variability. Runoff varied among sites (decreasing with increasing years of litter application), limiting the predictive capability of the soil extraction methods. Linking runoff characteristics with miscible displacement data may be a useful predictive tool and warrants further examination. 相似文献
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Chevalier LR 《Environmental monitoring and assessment》2003,84(1-2):19-33
Improper disposal, accidental spills and leaks of non-aqueousphase liquids (NAPL) such as gasoline, fuel oil and creosote result in long-term persistent sources of groundwater pollution.Column and 2-D tanks experiments were conducted to evaluate the use of surfactant-enhanced recovery of light non-aqueous phase liquids (LNAPL) in groundwater aquifers. These experiments focused on the use of surfactants to promote dissolution and mobilization in addition to evaluating the increase of aqueous phase permeability as residual NAPL is recovered. Further experiments are presented that show the innovative use of surfactants during primary pumping to recover free product canpotentially increase the amount of free product recovered, canpotentially reduce the amount of residual NAPL remaining afterprimary pumping and performs better than the use of surfactantsto mobilize trapped residual NAPL. 相似文献
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Martin Röösli Charlotte Braun-Fährlander Nino Künzli Lucy Oglesby Gaston Theis Markus Camenzind 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1115-1124
ABSTRACT The spatial variability of different fractions of particulate matter (PM) was investigated in the city of Basel, Switzerland, based on measurements performed throughout 1997 with a mobile monitoring station at six sites and permanently recorded measurements from a fixed site. Additionally, PM10 measurements from the following year, which were concurrently recorded at two urban and two rural sites, were compared. Generally, the spatial variability of PM4, PM10, and total suspended particulates (TSP) within this Swiss urban environment (area = 36 km2) was rather limited. With the exception of one site in a street canyon next to a traffic light, traffic density had only a weak tendency to increase the levels of PM. Mean PM10 concentration at six sites with different traffic densities was in the range of less than ±10% of the mean urban PM10 level. However, comparing the mean PM levels on workdays to that on weekends indicated that the impact of human activities, including traffic, on ambient PM levels may be considerable. Differences in the daily PM10 concentrations between urban and more elevated rural sites were strongly influenced by the stability of the atmosphere. In summer, when no persistent surface inversions exist, differences between urban and rural sites were rather small. It can therefore be concluded that spatial variability of annual mean PM concentration between urban and rural sites in the Basel area may more likely be caused by varying altitude than by distance to the city center. 相似文献
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Reserve Selection in Regions with Poor Biological Data 总被引:9,自引:0,他引:9