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1.
Acta sci., Biol. sci ; 41: e46936, 20190000. map, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460902

Resumo

The Atlantic Forest is highly anthropized, this reduce the areas of native vegetation and impacts the biodiversity of the biome. The objective of this study is to analyze forest remnants with native vegetation characteristics using a free GIS. This analysis takes place using landscape metrics and was based on the supervised vectorization of land use in the municipality of California, PR. The area of the vectored polygons was obtained and a classified, and then the calculation was made with the nearest neighbor index, mean distance observed, Patton diversity index and the perimeter/area ratio of forest fragments. The results show that most of the fragments have an area smaller than 1 ha, the fragments with more significant area (<50 ha) represent more than 16% of the native vegetation area. The small fragments are important to maintain the connectivity, since the withdrawal of these increases the mean distance observed and nearest neighbor index. Most of the fragments are elongated and amorphous in accordance with the perimeter/area ratio and the Patton diversity index respectively, this may demonstrate the fragments may be subject to edge effects. Even with these characteristics, these fragments may be part of what is planned in public policy for preservation in the Atlantic Forest in the state of Paraná. Therefore, even small fragments with little core area are important for maintaining biodiversity, especially in a highly anthropogenic landscape.


Assuntos
Biodiversidade , Florestas , Árvores
2.
Acta Sci. Biol. Sci. ; 36(3): 293-298, july.-sept.2014.
Artigo em Inglês | VETINDEX | ID: vti-695363

Resumo

The present study examined the influence of the availability of riparian vegetation and C3 emergent aquatic macrophytes on carbon assimilation by Prochilodus lineatus. The vegetal cover of these producers, available at 30 m of the bank, for the terrestrial ecosystem of the rivers Baia, Ivinheima and Paraná, was quantified with the image processing Landsat 5 TM, of the year 2000, period of sampling of the biological material at each river. The assimilation of the energy sources (riparian vegetation and C3 aquatic macrophytes, C4 aquatic macrophytes, periphyton, and phytoplankton) by P. lineatus was determined by analysis of stable carbon isotopes (13C). The area of vegetal cover was estimated at 1,017 km2 in the Ivinheima river, 669 km2 in the Paraná river, and 268 km2 in the Baia river. The assimilation of the carbon from riparian vegetation and aquatic macrophytes was proportional to the availability in the environment, but these producers were not the main source of carbon for P. lineatus. Thus, in the rivers with greater vegetation cover, consequently, these items had higher availability in the water body becoming an important carbon source for the species maintenance.(AU)


No presente estudo investigou-se a influência da disponibilidade da vegetação ripária e macrófitas aquáticas C3 emergentes sobre a assimilação de carbono por Prochilodus lineatus. A cobertura vegetal destes produtores, disponível a 30 m da margem para o ecossistema terrestre dos rios Baia, Ivinheima e Paraná, foi quantificada com o processamento de imagens Landsat 5 TM, do ano de 2000, período de amostragem do material biológico em cada rio. A assimilação das fontes de energia (vegetação ripária e macrófita aquática C3, macrófita aquática C4, perifiton e fitoplâncton) por P. lineatus foi determinada por análises de isótopos estáveis de carbono (13C). A área de cobertura vegetal foi estimada em, 1017 km2 no rio Ivinheima, 669 km2 no rio Paraná e 268 km2 no rio Baia. A assimilação por P. lineatus, do carbono proveniente da vegetação ripária e das macrófitas aquáticas foi proporcional a sua disponibilidade no ambiente, porém estes produtores não foram a principal fonte de carbono para a espécie. Sendo assim, os rios que apresentaram maior cobertura vegetal, consequentemente, tiveram maior disponibilidade no corpo aquático tornando-se importante fonte de carbono para a manutenção da espécie.(AU)


Assuntos
Animais , Caraciformes/metabolismo , Desenvolvimento Vegetal/fisiologia , Macrófitas/análise , Carbono/administração & dosagem , Carbono/análise
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