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Bryony A. Tolhurst Alastair I. Ward Richard J. Delahay Ann-Marie MacMaster Timothy J. Roper 《Applied animal behaviour science》2008,113(1-3):224-235
Behavioural investigations into the transmission of bovine tuberculosis (Mycobacterium bovis) between badgers and cattle suggest that badger activity in farm buildings may incur a significant risk of cross-infection. However, measures to exclude badgers from buildings have not been systematically field-tested. In the present study, remote surveillance and radio-tracking were used to monitor the effect of electric fencing manipulations on the frequency of badger incursions into feed stores and cattle housing, and on badger ranging behaviour. Electric fencing was effective in preventing access to the farm buildings where it was installed and also significantly reduced incursions into unfenced buildings. Badger home range and core activity areas tended to increase in size when the fencing was installed, although they did not extend beyond the boundaries of the relevant social group territories. We discuss the logistical constraints of using electric fencing in this context and conclude that it is a potentially useful method of reducing contact between badgers and cattle, within farm buildings and yards. 相似文献
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Takaharu Natsumeda 《Environmental Biology of Fishes》1998,53(3):295-301
Patterns of space use related to the activity of individual Japanese fluvial sculpins, Cottus pollux, were examined during the non-breeding season, in the upper reaches of the Inabe River, central Japan. Sculpins appeared more frequently at night than in daytime. Among 31 recaptured sculpins, 30 (96.8%) showed nocturnal activity patterns, there being no fish which exhibited an entirely diurnal activity pattern. Of 21 sculpins captured both in daytime and at night, the most common pattern of space use (n = 14, 66.7%) was that in which the nocturnal home range entirely encompassed the diurnal range. Overall, nocturnal home ranges were significantly larger than diurnal ranges. Active sculpins were rarely found on sand-associated substrata in daytime, but were seen more frequently on such substrata at night. 相似文献
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LCA of concrete and steel building frames 总被引:1,自引:0,他引:1
Asa Jonsson Thomas Bjorklund Anne -Marie Tillman 《The International Journal of Life Cycle Assessment》1998,3(4):216-224
The effects on the external environment of seven concrete and steel building frames representative of present-day building
technology in Sweden were analysed using LCA methodology. Objects of the study included frame construction and supplementary
materials. Several-storey offices and dwellings were studied. The functional unit was defined as one average m2 of floor area during the lifetime of the building. Inventory data were elaborated for concrete and steel production, the
building site, service life, demolition and final disposal. Parameters included were raw material use, energy use, emissions
to air, emissions to water and waste generation. The inventory results were presented and evaluated as such, in addition to
an interpretation by using three quantitative impact assessment methods. Parameters that weighed heavily were use of fossil
fuels, CO2, electricity, SOx
2 NOx
2 alloy materials and waste, depending on what assessment method was used. Over the life cycle, building production from cradle
to gate accounted for about the same contribution to total environmental loads as maintenance and replacement of heat losses
through external walls during service life, whereas demolition and final disposal accounted for a considerably lower contribution. 相似文献
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Mainly cyanobacteria, but also algae and fungi, were identified on the Jesuit missions San Ignacio Miní, Loreto, Santa María and Santa Ana, in NE Argentina. Many organisms were deeply pigmented, indicative of stressful conditions. San Ignacio samples of itacurú rock showed higher colonization and biodiversity, related to higher porosity allowing entry of water and nutrients. Sandstone from other locations was arenitous, containing 95% silicates. Physicochemical analyses suggested mobilization of ions, particularly Fe, from within the stone to the surface. This intense deteriorating colonization, together with climatic weathering, transforms the sandstone to a “protosoil,” for growth of bryophytes and higher plants. 相似文献
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Lenwood W. Hall Jr. William D. Killen Ronald D. Anderson Raymond W. Alden III 《人类与生态风险评估》2009,15(3):526-553
This study was designed to characterize benthic communities and physical habitat in both an urban (Kirker Creek) and residential (Pleasant Grove Creek) stream in California in late spring of 2006 and 2007. Concurrent water quality evaluations, physical sediment parameters, pyrethroids, bulk metals, and SEM/AVS ratios were also measured during both years of this study. The relationship of various benthic metrics to physical habitat metrics, pyrethroids, and metals was evaluated for each stream using stepwise multiple linear regressions with both years combined for each stream, as well as both years and both streams combined, to increase the statistical power for determining significant relationships. Physical habitat was determined to be poor in each stream during both years of sampling. More than 100 benthic taxa were reported annually for both streams based on 2006 and 2007 sampling. A significant result from the stepwise regression analysis combining data for 2 years across both streams is that when habitat metrics and to a lesser degree metals are considered in the statistical models pyrethroids do not display any significant relationships to the benthic metrics. In summary, it is apparent from this analysis that the health of benthic communities in both streams is primarily affected by habitat metrics. 相似文献
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Justine A. Smith Yiwei Wang Christopher C. Wilmers 《Proceedings. Biological sciences / The Royal Society》2015,282(1802)
The fear induced by predators on their prey is well known to cause behavioural adjustments by prey that can ripple through food webs. Little is known, however, about the analogous impacts of humans as perceived top predators on the foraging behaviour of carnivores. Here, we investigate the influence of human-induced fear on puma foraging behaviour using location and prey consumption data from 30 tagged individuals living along a gradient of human development. We observed strong behavioural responses by female pumas to human development, whereby their fidelity to kill sites and overall consumption time of prey declined with increasing housing density by 36 and 42%, respectively. Females responded to this decline in prey consumption time by increasing the number of deer they killed in high housing density areas by 36% over what they killed in areas with little residential development. The loss of food from declines in prey consumption time paired with increases in energetic costs associated with killing more prey may have consequences for puma populations, particularly with regard to reproductive success. In addition, greater carcass availability is likely to alter community dynamics by augmenting food resources for scavengers. In light of the extensive and growing impact of habitat modification, our study emphasizes that knowledge of the indirect effects of human activity on animal behaviour is a necessary component in understanding anthropogenic impacts on community dynamics and food web function. 相似文献