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Caudal autotomy (tail shedding) is a defence mechanism against predation which is used by lizards when other tactics, such
as crypsis and escape, prove ineffective. The speed at which autotomy occurs has important implications for survival, and
the accuracy of tail loss is of consequence for an individual’s future fitness. Autotomy is shaped by both taxon-specific
tail morphology as well as environmental factors such as predator history, and it can be difficult to distinguish between
these processes. In this study, the frequency of tail-regeneration observed (field rate of autotomy), latency (speed of autotomy
in the laboratory) and accuracy of tail loss were measured in six lizard species from two families (Scincidae and Diplodactylidae).
The field rate and latency of autotomy was similar among all species except for the large nocturnal skink Oligosoma macgregori, which was less likely to autotomise. Latency and field rates of autotomy were not correlated, implying that the field rates
of autotomy are related to predation attacks, social interactions, or some other environmental factor, rather than an innate
disposition to autotomy. Further study, for example comparing populations with low and high predation pressure, will help
to explain which of these factors are influencing autotomy rates. 相似文献
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Amvrossios C. Bagtzoglou Eric D. Kenney April Hiscox David R. Miller 《Environmental Forensics》2014,15(2):147-158
This work applies optimization and an Eulerian inversion approach presented by Bagtzoglou and Baun in 2005 in order to reconstruct contaminant plume time histories and to identify the likely source of atmospheric contamination using data from a real test site for the first time. Present-day distribution of an atmospheric contaminant plume as well as data points reflecting the plume history allow the reconstruction and provide the plume velocity, distribution, and probable source. The method was tested to a hypothetical case and with data from the Forest Atmosphere Transfer and Storage (FACTS) experiment in the Duke experimental forest site. In the scenarios presented herein, as well as in numerous cases tested for verification purposes, the model conserved mass, successfully located the peak of the plume, and managed to capture the motion of the plume well but underestimated the contaminant peak. 相似文献
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Elisabeth Nyberg Sara Danielsson Ulla Eriksson Suzanne Faxneld Aroha Miller Anders Bignert 《Ambio》2014,43(1):45-57
Polychlorinated biphenyls (PCBs) have been monitored in perch (Perca fluviatilis), pike (Esox lucius), and Arctic char (Salvelinus alpinus) in reference lakes since the late 1960s. Temporal trends and spatial patterns are currently monitored in nine and 32 lakes, respectively. Overall, PCB concentrations are decreasing. However, this is not consistent for all congeners across all lakes and species. Perch has comparatively low PCB concentrations relative to suggested target levels, but individual congener concentrations in some lakes are concerningly high. No temporal trend is seen for CB-118 and CB-153 in perch, but significant decreasing trends exist for Arctic char and pike, for which monitoring started earlier than for perch. The lower/higher chlorinated congener ratio decreased over time in most lakes, indicating fewer new emissions. CB-118 and CB-153 concentrations in perch show spatial gradients across Sweden, with higher concentrations found near urban/industrial areas. 相似文献
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Coupling of the Water Cycle with Patterns of Urban Growth in the Baltimore Metropolitan Region,United States 下载免费PDF全文
Aditi S. Bhaskar Claire Jantz Claire Welty Scott A. Drzyzga Andrew J. Miller 《Journal of the American Water Resources Association》2016,52(6):1509-1523
Regional municipal water plans typically do not recognize complex coupling patterns or that increased withdrawals in one location can result in changes in water availability in others. We investigated the interaction between urban growth and water availability in the Baltimore metropolitan region where urban growth has occurred beyond the reaches of municipal water systems into areas that rely on wells in low‐productivity Piedmont aquifers. We used the urban growth model SLEUTH and the hydrologic model ParFlow.CLM to evaluate this interaction with urban growth scenarios in 2007 and 2030. We found decreasing groundwater availability outside of the municipal water service area. Within the municipal service area we found zones of increasing storage resulting from increased urban growth, where reduced vegetation cover dominated the effect of urbanization on the hydrologic cycle. We also found areas of decreasing storage, where expanding impervious surfaces played a larger role. Although the magnitude of urban growth and change in water availability for the simulation period were generally small, there was considerable spatial heterogeneity of changes in subsurface storage. This suggests that there are locally concentrated areas of groundwater sensitivity to urban growth where water shortages could occur or where drying up of headwater streams would be more likely. The simulation approach presented here could be used to identify early warning indicators of future risk. 相似文献
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Miller Aubrey D. Vaske Jerry J. Squires John R. Olson Lucretia E. Roberts Elizabeth K. 《Environmental management》2017,59(1):50-67
Environmental Management - Parks and protected area managers use zoning to decrease interpersonal conflict between recreationists. Zoning, or segregation, of recreation—often by non-motorized... 相似文献
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