Grazers
Mostrando 1-12 de 26 artigos, teses e dissertações.
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1. Grazing of particle-associated bacteria-an elimination of the non-viable fraction
Abstract Quantification of bacteria being grazed by microzooplankton is gaining importance since they serve as energy subsidies for higher trophic levels which consequently influence fish production. Hence, grazing pressure on viable and non-viable fraction of free and particle-associated bacteria in a tropical estuary controlled mainly by protist grazers wa
Braz. J. Microbiol.. Publicado em: 2017-03
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2. Efeitos da rugosidade de substratos, distúrbios físicos e organismos pastejadores na estruturação de assembleias de algas bênticas e na biomassa perifítica em um riacho subtropical : uma abordagem experimental
Os estudos apresentados nesta tese tiveram como objetivo compreender aspectos da organização de assembleias de algas bênticas em riachos. Foi avaliado especificamente o efeito da heterogeneidade de habitat na escala de rugosidade de substratos e sua interação com distúrbios hidrológicos e organismos pastejadores (grazers). Utilizou-se uma abordagem ex
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2012
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3. Sucessão ecológica em parcelas orgânicas de madeira, macroalgas e em carcassas de baleia no mar profundo; e similaridade de espécies entre habitats redutores no talude continental da Califórnia (Pacífico Nordeste) / Whales, wood and kelp islands in the deep-sea: ecological succession and species overlap with other chemosynthetic habitats in the Californian continental slope (NE Pacific)
Sunken parcels of macroalgae, wood and whale carcasses provide important oases of organic enrichment at the deep-sea floor, but sediment community structure and succession around these habitat islands are poorly evaluated. We experimentally implanted parcels of kelp and wood falls nearby a 30-ton deep-sea whale-fall at 1670 m in the Santa Cruz Basin (SCr; NE
Publicado em: 2009
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4. Improved Method for Determining Bacterial Filtration Rates in Zooplankton
Filtration rates were determined for a natural population of zooplankton grazers (Bosmina longirostris [Müll.], Cyclops vicinus vicinus [Ulianine], Acanthodiaptomus denticornis [Wierz.], and Daphnia longispina [Müll.]) by using 3H-labeled bacteria as food for these organisms. There was a relationship between filtration rates of the major zooplankton grazer
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5. Rates of Microbenthic and Meiobenthic Bacterivory in a Temperate Muddy Tidal Flat Community
Rates of bacterivory in micro- and meiobenthic species were determined by an improved technique in a muddy tidal flat community in Boston Harbor, Mass. The predominant grazers of bacteria were identified, and their rates of grazing were measured in the top 1 cm of the sediment. Grazing rates were measured by a fluorescence-labeled bacteria (FLB) technique. A
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6. Relationships between oral morphology and feeding style in the Ungulata: a phylogenetically controlled evaluation.
In ungulates it is argued that specialization in the consumption of a particular type of food (feeding style) is reflected in morphological adaptations of the organs involved in the selection, processing and digestion of food. We analysed the differences in size and morphology of some oral traits that have been functionally related to food-selection ability
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7. Productivity, consumers, and the structure of a river food chain.
We tested models of food chain dynamics in experimentally manipulated channels within a natural river. As light levels increased, primary productivity and the biomass of algae and primary predators increased, but the biomass of grazers remained relatively constant. In the presence of a fourth trophic level, algae and primary predators decreased, but grazers
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8. Nitrogen Mineralization by Acanthamoeba polyphaga in Grazed Pseudomonas paucimobilis Populations
Nitrogen mineralization was studied in a simple grazing system in which the protozoan Acanthamoeba polyphaga was grown with the bacterium Pseudomonas paucimobilis (two soil organisms isolated from the shortgrass prairie in northern Colorado). In different experiments, either carbon or nitrogen was adjusted to be in limiting amounts. When carbon was limiting,
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9. Intrinsic ruminal innervation in ruminants of different feeding types
According to their feeding habits, ruminants can be classified as grazers, concentrate selectors and those of intermediate type. The different feeding types are reflected in distinct anatomical properties of the forestomachs. The present study was designed to investigate whether the intrinsic innervation patterns of the rumen (the main part of the forestomac
Blackwell Science Inc.
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10. Mixotrophs combine resource use to outcompete specialists: Implications for aquatic food webs
The majority of organisms can be grouped into those relying solely on photosynthesis (phototrophy) or those relying solely on the assimilation of organic substances (heterotrophy) to meet their requirements for energy and carbon. However, a special life history trait exists in which organisms combine both phototrophy and heterotrophy. Such “mixotrophy” i
National Academy of Sciences.
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11. Effect of Silicate Grain Shape, Structure, and Location on the Biomass and Community Structure of Colonizing Marine Microbiota
Microbiota colonizing silica grains of the same size and water pore space, but with a different microtopography, showed differences in biomass and community structure after 8 weeks of exposure to running seawater. The absence of surface cracks and crevices resulted in a marked diminution of the total microbial biomass measured as lipid phosphate and total ex
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12. Effects of productivity, consumers, competitors, and El Niño events on food chain patterns in a rocky intertidal community
We experimentally manipulated nutrient input to a rocky intertidal community, using nutrient-diffusing flowerpots, to determine (i) whether nutrients limited intertidal productivity, (ii) how a large-scale oceanographic disturbance (an El Niño event) affected patterns of nutrient limitation, (iii) the relative impacts of molluscan grazers and nutrient
The National Academy of Sciences of the USA.