Caracterização de processos hidrológicos em ambientes de estágio inicial e avançado de regeneração em Floresta Atlântica

• Autor(a) principal: Freitas, João Paulo Oliveira de
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3166
• topic: Hidrologia florestal; Ciclo hidrológico; Bacia hidrográfica; Recuperação ecológica; Mata Atlântica; Forest hydrology; Hydrological cycle; Watershed; Ecological recovery; Atlantic Forest; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::CONSERVACAO DA NATUREZA

Studying the processes occurring inside the forest is of fundamental importance in watershed management. With the reduction of its original area, the small rainforest fragments have become real laboratories essential to the study of water dynamics. This study aimed to compare the internal precipitation, stem flow, interception and effective rainfall in a rainforest fragment in two successional stages; evaluate runoff and litter influences on it, as well as the water retention capacity of litter and flow of the basin of Mata do Paraíso. This study was conducted at the Estação de Pesquisas, Treinamento e Educação Ambiental Mata do Paraíso, located in Viçosa, in the Zona da Mata of Minas Gerais from January 2012 to July 2013. The area has 194 ha and is located in the area of Seasonal Semideciduous Forest, making up a mosaic of different successional stages. For the assessment of effective rainfall and interception, three 20 x 20m plots with rain gauges of throughfall were allocated in each regeneration stage. In each plot of throughfall a sub plot of 10 x 10m was allocated, in which stemflow collectors were installed in all trees with circumference ≥ 15 cm to 1.30m from the soil (CAP). The runoff was obtained by the average of the three plots with presence of litter and three plots without litter, allocated in the initial area of regeneration. To monitor the flow, the method with direct reading of the volume with a lab bucket was used and the time marked with a stopwatch. The effective rainfall and interception were 1544 mm and 390 mm respectively for the initial stage and 1435 mm and 499 mm, respectively, for the advanced stage of regeneration, corresponding, respectively, to 79.8%, 20.16%, 74.2%, 25.80% of the precipitation in the open, which was equal to 1934 mm. Runoff in the plot with litter was 21 mm, and 24 mm in the bare soil plot, corresponding to 1.78% and 2.00% of the precipitation in the open. The water retention capacity of litter was 3.747 kg / kg. The average flow rate during the study period was 1.89 l/s. It was observed during the study that only the stem flow differ significantly between the two successional stages. Despite having no difference between plots with litter and bare soil in the runoff, its presence is of fundamental importance to the ecosystem. The flow shows a rapid response to rainfall; however, it is only in high rainfall that they generate high peak flows.