Foodweb
Mostrando 1-12 de 15 artigos, teses e dissertações.
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1. Effects of the introduction of an omnivorous fish on the biodiversity and functioning of an upland Amazonian lake
RESUMO A introdução de espécies não nativas é uma ameaça aos ecossistemas de água doce. Embora a onivoria e a predação intraguilda sejam comuns nesses sistemas, os efeitos da introdução de peixes onívoros nas comunidades pelágicas e litorâneas é pouco conhecido. Nós testamos as previsões da teoria da teia trófica considerando os efeitos da
Acta Amaz.. Publicado em: 12/08/2019
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2. Isotopic variation among Amazonian floodplain woody plants and implications for food-web research
Isotopic variation within food sources adds uncertainty to models intended to reconstruct trophic pathways. Understanding this variation is pivotal for planning sampling protocols for food-web research. This study investigates natural variation in C and N stable isotopes among plant species in two western Amazon flooded forests with contrasting watershed bio
Biota Neotrop.. Publicado em: 14/06/2016
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3. Composição florística e fauna associada das ilhas flutuantes livres, Rio Paraguai, Corumbá, MS.
As ilhas flutuantes livres englobam várias espécies vegetais tais como camalotes e gramíneas. Nas folhas e raízes destas plantas encontra-se uma diversidade de organismos. Este trabalho teve como objetivo fazer o levantamento das espécies vegetais componentes das ilhas flutuantes livres e conhecer os organismos associados e seus hábitos alimentares. Fr
SIMPÓSIO SOBRE RECURSOS NATURAIS E SOCIOECONÔMICOS DO PANTANAL. Publicado em: 2011
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4. Identification of Astyanax altiparanae (Teleostei, Characidae) in the Iguaçu River, Brazil, based on mitochondrial DNA and RAPD markers
Astyanax fishes are among the most important food-web components of South America rivers. In the Iguaçu River basin, the Astyanax genus is represented mainly by endemic species. For millions of years, that hydrographic basin has been geographically isolated from the Paraná River basin by the Iguaçu Falls. Recently, a species from the Upper Paraná River b
Genetics and Molecular Biology. Publicado em: 2002
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5. The more food webs change, the more they stay the same
Here, we synthesize a number of recent empirical and theoretical papers to argue that food-web dynamics are characterized by high amounts of spatial and temporal variability and that organisms respond predictably, via behaviour, to these changing conditions. Such behavioural responses on the landscape drive a highly adaptive food-web structure in space and t
The Royal Society.
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6. Cascading extinctions and community collapse in model food webs
Species loss in ecosystems can lead to secondary extinctions as a result of consumer–resource relationships and other species interactions. We compare levels of secondary extinctions in communities generated by four structural food-web models and a fifth null model in response to sequential primary species removals. We focus on various aspects of food-web
The Royal Society.
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7. Evolutionary emergence of size-structured food webs
Explaining the structure of terrestrial and aquatic food webs remains one of the most important challenges of ecological theory. Most existing models use emergent properties of food webs, such as diversity and connectance as parameters, to determine other food-web descriptors. Lower-level processes, in particular adaptation (whether by behavioral, developmen
National Academy of Sciences.
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8. Food-web structure and network theory: The role of connectance and size
Networks from a wide range of physical, biological, and social systems have been recently described as “small-world” and “scale-free.” However, studies disagree whether ecological networks called food webs possess the characteristic path lengths, clustering coefficients, and degree distributions required for membership in these classes of networks. O
The National Academy of Sciences.
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9. Food-web constraints on biodiversity–ecosystem functioning relationships
The consequences of biodiversity loss for ecosystem functioning and ecosystem services have aroused considerable interest during the past decade. Recent work has focused mainly on the impact of species diversity within single trophic levels, both experimentally and theoretically. Experiments have usually showed increased plant biomass and productivity with i
National Academy of Sciences.
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10. Inter- and intraspecific trait compensation of defence mechanisms in freshwater snails.
Trait compensation occurs when mechanically independent adaptations are negatively correlated. Here, we report the first study to demonstrate trait compensation in predator-defence adaptations across several species. Freshwater pulmonate snails exposed experimentally to predation chemical cues from fishes and crushed conspecifics showed clear interspecific d
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11. Two degrees of separation in complex food webs
Feeding relationships can cause invasions, extirpations, and population fluctuations of a species to dramatically affect other species within a variety of natural habitats. Empirical evidence suggests that such strong effects rarely propagate through food webs more than three links away from the initial perturbation. However, the size of these spheres of pot
The National Academy of Sciences.
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12. Food-web structure and ecosystem services: insights from the Serengeti
The central organizing theme of this paper is to discuss the dynamics of the Serengeti grassland ecosystem from the perspective of recent developments in food-web theory. The seasonal rainfall patterns that characterize the East African climate create an annually oscillating, large-scale, spatial mosaic of feeding opportunities for the larger ungulates in th
The Royal Society.