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1.
Braz J Biol ; 70(1): 47-53, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20231959

RESUMO

We studied the role of white-lipped and collared peccaries (Tayassu pecari and Pecari tajacu) as seed predators and dispersers in the Atlantic rainforest of Brazil. The Atlantic rainforest ecosystem is highly threatened and has experienced dramatic declines in its populations of large mammals. Local extinctions can disrupt essential plant-animal interactions such as seed dispersion and seed predation. We tracked seeds from time of consumption to germination to assess the direct impact peccaries have on seed survival. We offered fruits of 20 species found in the Atlantic rainforest to the peccaries. Seeds were categorised as intact, scarified, ingested or defecated, and germination tests were performed. The overall impact by both peccary species was similar. Seeds were sometime scarified by mastication, always with fatal consequences. Most seeds that were consumed were destroyed during ingestion and digestion. Only small seeds (<10 mm) were found in the feces and germination tests suggest a positive effect from the passage through the guts. Peccaries clearly have a double role as both seed predators and as small seeds dispersers, which is a specialised role within the granivore/frugivore community of the Atlantic rainforest.


Assuntos
Artiodáctilos/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Germinação/fisiologia , Sementes , Animais , Artiodáctilos/classificação , Brasil , Defecação/fisiologia
2.
Braz. j. biol ; 70(1): 47-53, Feb. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-539732

RESUMO

We studied the role of white-lipped and collared peccaries (Tayassu pecari and Pecari tajacu) as seed predators and dispersers in the Atlantic rainforest of Brazil. The Atlantic rainforest ecosystem is highly threatened and has experienced dramatic declines in its populations of large mammals. Local extinctions can disrupt essential plant-animal interactions such as seed dispersion and seed predation. We tracked seeds from time of consumption to germination to assess the direct impact peccaries have on seed survival. We offered fruits of 20 species found in the Atlantic rainforest to the peccaries. Seeds were categorised as intact, scarified, ingested or defecated, and germination tests were performed. The overall impact by both peccary species was similar. Seeds were sometime scarified by mastication, always with fatal consequences. Most seeds that were consumed were destroyed during ingestion and digestion. Only small seeds (<10 mm) were found in the feces and germination tests suggest a positive effect from the passage through the guts. Peccaries clearly have a double role as both seed predators and as small seeds dispersers, which is a specialised role within the granivore/frugivore community of the Atlantic rainforest.


O papel dos porcos-do-mato, cateto (Pecari tajacu) e queixada (Tayassu pecari), como predadores e dispersores de sementes foram estudados no contexto da Mata Atlântica. Neste ecossistema extremamente ameaçado, as populações de grande mamíferos vêm diminuindo drasticamente. A extinção local de algumas dessas espécies pode modificar as interações plantas-animais como a dispersão e a predação de sementes. Sementes de 20 espécies de plantas lenhosas da Mata Atlântica foram acompanhadas desde a ingestão até a germinação para avaliar o impacto direto que queixadas e catetos têm sobre a sobrevivência destas sementes. As sementes foram categorizadas em: ignoradas, escarificadas (danos mecânicos), engolidas ou defecadas. Também foram realizados testes de germinação. O impacto das duas espécies de foi similar. Às vezes, as sementes foram escarificadas por mastigação, com consequências letais. A maioria das sementes consumidas foi destruída durante a ingestão e digestão. Somente sementes pequenas (<10 mm) foram defecadas. Os testes de germinação sugerem um impacto positivo nas sementes que passaram pelo trato digestivo. Os porcos desempenham claramente um papel duplo: predadores de sementes e dispersores de sementes pequenas, um papel especializado dentro da communidade de frugívoros/granívoros na Mata Atlântica.


Assuntos
Animais , Artiodáctilos/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Germinação/fisiologia , Sementes , Artiodáctilos/classificação , Brasil , Defecação/fisiologia
3.
Environ Manage ; 21(3): 359-65, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9106411

RESUMO

/ It has been suggested that the general public should be moreinvolved in environmental policy and decision making. It is important forthem to realize that they will have to live with the consequences ofenvironmental policies and decisions. Consequently, policy makers shouldconsider the concerns and opinions of the general public before makingdecisions on environmental issues. This raises questions such as: How can weintegrate the perceptions and reactions of the general population inenvironmental decisions? What kind of public participation should weconsider? In the present study, using a new regional ecosystem model, weattempted to integrate these aspects in its decision making model byincluding the formation of an advisory committee to resolve problems relatedto waste management. The advisory committee requested the activeparticipation of representatives from all levels of the community: economic,municipal, and governmental intervenors; environmental groups; and citizens.Their mandates were to examine different management strategies available inthe region, considering all the interdisciplinary aspects of each strategy,elaborate recommendations concerning the management strategies that are mostsuitable for all, and collaborate in communication of the information to thegeneral population. The results showed that at least in small municipalitiessuch an advisory committee can be a powerful tool in environmental decisionmaking. Conditions required for a successful consultation process, such aseveryday lay language and the presence of a facilitator other than ascientific expert, are discussed.KEY WORDS: Public consultation; Environmental policies;Interdisciplinary aspects; Municipal sewage sludge management; Generalpopulation; Decision-making process

4.
Environ Pollut ; 92(1): 67-72, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-15091412

RESUMO

The survival of faecal and total coliform bacteria and Streptococcus faecalis (indicator bacteria) were monitored in experimental plots receiving various amounts of biological or dephosphatation municipal sewage sludge. Biological sludge was applied on coniferous and mixed regenerative forest soils. The results show that except for total coliforms, there was little significant treatment effect on the indicator bacteria numbers in all of the sites. In most cases, there was a significant time effect, indicating that bacterial populations vary over time, according to environmental factors such as temperature, moisture or nutrient level conditions. In total coliform bacteria, populations varied over time but also in function of treatment levels. The present study suggests that even if the standards of Québec (Canada) for sludge application are respected, there may be some risk for bacterial contamination depending on the types of sewage sludge and forest habitat. Although there is only a short-term effect, high slopes can influence the movement of the indicator bacteria and may potentially cause some contamination problems.

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