Sources, sinks, and drains in double breeding bird species?
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منابع مشابه
Sources, sinks, and drains in double breeding bird species?
The recognition of a second breeding season in some migratory bird species by Rohwer et al. (1) creates an interesting scenario for conserving migratory bird populations. Previously, conservation biologists assessed sources as large undisturbed habitats and sinks as degraded breeding grounds (2), and treated fragmented and deforested habitats in nonbreeding “wintering” areas as drains on the po...
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Species in a Colorado subalpine ecosystem show subtle interdependences. Red-naped sapsuckers play two distinct keystone roles. They excavate nest cavities in fungus-infected aspens that are required as nest sites by two species of swallows, and they drill sap wells into willows that provide abundant nourishment for themselves, hummingbirds, orange-crowned warblers, chipmunks, and an array of ot...
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We count labeled acyclic digraphs according to the number sources, sinks, and edges. 1. Counting acyclic digraphs by sources. Let An(t;α) = ∑ D αt, where the sum is over all acyclic digraphs D on the vertex set [n] = {1, 2, . . . , n}, e(D) is the number of edges of D, and s(D) is the number of sources of D; that is, the number of vertices of D of indegree 0. Let An(t) = An(t; 1). To find a rec...
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Through estimations of above-and below-ground standing biomass, annual biomass increment, fine root production and turnover, litterfall, canopy respiration and total soil CO 2 efflux, a carbon balance on seasonal and yearly timescales is developed for a Eucalypt open-forest savanna in northern Australia. This carbon balance is compared to estimates of carbon fluxes derived from eddy covariance ...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2010
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0912607107