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Fritz Braun 《Die Naturwissenschaften》1930,18(28):652-652
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Chris R. Pavey Chris J. Burwell Gerhard Körtner Fritz Geiser 《Die Naturwissenschaften》2009,96(6):679-683
One of the energetic benefits of daily torpor over prolonged hibernation is that it enables animals to regularly forage and,
therefore, replenish food reserves between bouts of torpor. However, little is known about the diet of predators undergoing
torpor or whether differences in prey composition among individuals influence torpor characteristics. Here, we test the hypothesis
that prey composition affects winter torpor use and patterns of a population of carnivorous marsupial, the brush-tailed mulgara
(Dasycercus blythi), in the Great Sandy Desert, Australia. Mulgaras in the study population captured a wide range of prey including vertebrates
(mammals, reptiles, birds), seven insect orders, spiders and centipedes. The proportion of vertebrates in the diet was negatively
correlated with both frequency of torpor use and maximum bout duration. This variation in torpor use with diet can be explained
by the higher energetic content of vertebrates as well as their larger size. Even assuming uniform intake of prey biomass
among individuals, those that subsisted on an invertebrate-dominated diet during winter apparently suffered energetic shortages
as a result of the scarcity of invertebrate taxa with high energy content (such as insect larvae). Our study is the first
to demonstrate a link between diet composition and daily torpor use in a free-ranging mammal. 相似文献
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Physical and Chemical Connectivity of Streams and Riparian Wetlands to Downstream Waters: A Synthesis 下载免费PDF全文
Ken M. Fritz Kate A. Schofield Laurie C. Alexander Michael G. McManus Heather E. Golden Charles R. Lane William G. Kepner Stephen D. LeDuc Julie E. DeMeester Amina I. Pollard 《Journal of the American Water Resources Association》2018,54(2):323-345
Streams, riparian areas, floodplains, alluvial aquifers, and downstream waters (e.g., large rivers, lakes, and oceans) are interconnected by longitudinal, lateral, and vertical fluxes of water, other materials, and energy. Collectively, these interconnected waters are called fluvial hydrosystems. Physical and chemical connectivity within fluvial hydrosystems is created by the transport of nonliving materials (e.g., water, sediment, nutrients, and contaminants) which either do or do not chemically change (chemical and physical connections, respectively). A substantial body of evidence unequivocally demonstrates physical and chemical connectivity between streams and riparian wetlands and downstream waters. Streams and riparian wetlands are structurally connected to downstream waters through the network of continuous channels and floodplain form that make these systems physically contiguous, and the very existence of these structures provides strong geomorphologic evidence for connectivity. Functional connections between streams and riparian wetlands and their downstream waters vary geographically and over time, based on proximity, relative size, environmental setting, material disparity, and intervening units. Because of the complexity and dynamic nature of connections among fluvial hydrosystem units, a complete accounting of the physical and chemical connections and their consequences to downstream waters should aggregate over multiple years to decades. 相似文献