Navegando por Autor "MEDEIROS, Priscila Sanjuan de"

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Acesso aberto (Open Access)
Fungos poróides (Agaricomycetes) na Floresta Nacional de Caxiuanã: fenologia e relação com o substrato, topografia e fatores micrometeorológicos
(Universidade Federal do Pará, 2011-03-30) MEDEIROS, Priscila Sanjuan de; CATTANIO, José Henrique; http://lattes.cnpq.br/1518769773387350
This study was conducted in one of the sites of Amazon Biodiversity Program (PPBio) located in the Caxiuanã National Forest (PA) and aimed to present the poroid fungi with emphasis on new record, analyze the relationship of these fungi with the woody substrate and to examine the association between micrometeorological variables (air temperature, relative humidity and rainfall) for one year, in relation to environmental variables, produced by topography, with richness, density, and phenology of these fungi. Were identified 76 species of poroid fungi, distributed in 27 genera and 5 families. The species Cerrena sclerodepsis, Phellinus dependens and Trametes pavonia represent the first records for the Pará state. Microporellus iguazuensis is mentioned for the first time in Brazil and presents the proposal of a new species to science, called Microporellus hirsuta. Most of the species was considered rare and showed preference for substrates in the early decomposition stages. The number of occurrences of basidiomata and fungi species was higher on the stem of the families plants Caesalpinaceae, Sapotaceae, Annonaceae, Mimosaceae and Lecythidaceae, respectively, and at substrate with a smaller diameter. It was expected that differences in microclimate generated by different altitudes, in a short topographic gradient, were sufficient to generate differences in the poroid fungal community. However, although it was found a greater number of species in a region called the intermediate, this difference was not significant. The largest number of individuals was found in the first rains and the richness is positively correlated with rainfall. The activity index of basidioma production of the abundant species was higher during the first rains after the dry period. This study represents an advance in understanding the relationships of the fungi with the environment in which they grow, mainly in tropical regions, but many studies still need to be developed to clarify these relationships.
Acesso aberto (Open Access)
Indicadores ambientais para funcionalidade ecológica em florestas secundárias de diferentes idades na Amazônia Oriental
(Universidade Federal do Pará, 2016-06-17) MEDEIROS, Priscila Sanjuan de; FERREIRA, Leandro Valle; http://lattes.cnpq.br/8103998556619871
Currently secondary forests occupy about 25% of the Amazon region, and have received attention for ecosystemic services they provide. Beyond the role in carbon sequestration, soil protection and water sources, secondary forests can shelter an enormous diversity. However, public policies directed to the maintenance of the succession process these forests are required, so that they can contribute with maintenance of biodiversity and environmental services. The objective of this work was to evaluate the ecological functionality of secondary forests of different ages, using as indicators that successional dynamics vegetation, seed bank, soil macrofauna and arbuscular mycorrhizal fungi. The study was developed in areas of primary forest and secondary upland forest of different ages in Caxiuanã National Forest, in the state of Pará. We applied the Chronosequence method which is to the methodology most used for succession studies. 40 areas were selected, with an average size of 0.75 hectares, three areas of primary forest and 37 of secondary forest (capoeira). The time of abandonment these areas varies between 1 and 40 years and all have similar usage history. In each area it was implanted a permanent plot where vegetables individuals were sampled (understory and forest stratum) and where soil samples were taken to evaluate the seed bank and the density of arbuscular mycorrhizal fungi. In these plots was applied the methodology of Program "Tropical Soil Biology and Fertility" (TSBF) for the sampling of the soil macrofauna and earthworms. Six campaigns were conducted, three in the dry season and three in the rainy season. Were also collected soil moisture data, canopy opening, litter stock, amount of fine roots and soil physicochemical variables (K, P, Na, Ca, Mg, Al, N, pH, sand coarse sand fine , Silt and clay full). For a better compression of the relationships between biotic and abiotic variables data were analyzed and discussed in an approach continues and other categorical, classifying areas into four groups according to age of the secondary forest (stage 1-0 to 10 years; stage 2 – 11 to 25; stage 3 26 to 40; stage 4 primary forest). Vegetation variables and the life forms present in the seed bank showed strong relationship with the age of the secondary forest. The use of macrofauna as bioindicator demonstrated to be an excellent strategy for monitoring of secondary forests, enabling the conservation of these habitats and the correct management of their resources. Already the density and biomass of earthworms have low relationship with the successional process. The arbuscular mycorrhizal fungi showed up to be good indicators in the separation of primary and secondary forest. With this, we have environmental variables of vegetation, seed bank and soil macrofauna that have potential to be used in a quality index of ecosystemic functions in secondary upland forest.