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121.
Axel Strauß Katrin Y. Solmsdorff Roger Pech Jens Jacob 《Behavioral ecology and sociobiology》2008,62(10):1551-1558
Predators can strongly influence the microhabitat use and foraging behaviour of prey. In a large-scale replicated field experiment
in East Gippsland, Australia, we tested the effects of reduced alien red fox (Vulpes vulpes) and alien wild dog (Canis lupus familiaris) abundance (treatment) on native bush rat (Rattus fuscipes) behaviour. Bush rats are exposed to two main guilds of predators, namely mammalian carnivores and birds of prey. Tracking
rat movements using the spool-and-line technique revealed that, in treatment sites, rats used ground cover, which provides
shelter from predators, less often than at unmanipulated fox and wild dog abundance (non-treatment sites). In treatment sites,
rats more frequently moved on logs where they would have been exposed to hunting foxes and dogs than in non-treatment sites.
Furthermore, in treatments, rats showed a preference for understorey but not in non-treatments. Hence, bush rats adapted their
behaviour to removal of alien terrestrial predators. Giving-up densities (GUDs) indicated no treatment effects on the marginal
feeding rate of bush rats. Interestingly, GUDs were higher in open patches than in sheltered patches, suggesting higher perceived
predation risk of bush rats during foraging at low versus high cover. The lack of treatment effects on GUDs but the clear
response of bush rats to cover may be explained by the impact of predators other than foxes and wild dogs. 相似文献
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The consideration of time in environmental research allows new insights into the fundamentals of environmental research and new pathways for perceiving and answering questions which might arise in environmental research. In order to take this all into account, one must realize that ecological systems have a history and that both the spatial aspects and the chronological expansion of these systems must be taken into consideration. Considering temporalities, rhythms and time scales as well as their interdependencies in environmental research and environmental protection enables us to obtain a better understanding. The significance of relationships and functions in ecological systems can be perceived better as well. The impact of pollutants as well as the outcome of human actions in ecology, and in economics and politics, is consequently mandatory for not only a spatial, but also for the involved temporal scales. 相似文献
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DM Peter Lorenz Rainer Bollmann Georg Klaus Hinkel Marco Mächler Gabriele Siegert Gudrun Stamminger Jörg Wendisch Sabine Ziemer 《黑龙江环境通报》1991,11(11):819-825
The study of the fetal platelet count and size can, according to the literature, be used for the prenatal diagnosis of the Wiskott-Aldrich syndrome (WAS). So far, no affected fetuses have been identified by this method. All pregnancies in which this method had been applied to resulted, as correctly predicted, in the birth of normal children. Here we report on a familial case of WAS where the haematological parameters failed to reveal the affected second child. Hence we assume that the platelet count and size of platelets remain normal in fetuses with WAS to the gestational age of 22 weeks and cannot be used for prenatal diagnosis. 相似文献
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