Dinâmica bacteriana em sedimentos costeiros de Ubatuba, São Paulo / Bacterial dynamics in coastal sediments of Ubatuba, São Paulo
AUTOR(ES)
Paula Carpintero de Moraes
DATA DE PUBLICAÇÃO
2007
RESUMO
Coastal sediments are characterized by high organic matter contents. Bacteria play a key role in organic matter decomposition and are essential in the nutrient recycling process. Moreover, represent an important food source for meio- and macrofaunal organisms. The present study aimed to evaluate the abundance and biomass of the benthic bacterial community in two bays of the coastal region of Ubatuba (SP). Bacterial abundance and biomass were compared with the distribution and abundance of different organic matter sources (marine, terrestrial and anthropogenic) and with the structure of the benthic community. We collected samples every two months for a period of one year in four stations on each bay along a coast-ocean transect. Tube cores were used to collect sediment samples, which were sliced on board in three layers (0-2, 2-5 and 5-10 cm). Bacterial abundance and biomass were counted and measured under epifluorescence microscopy and bacterial activity was estimated by the frequency of dividing cells. Information on sediment grain size distribution, quality and quantity of organic matter, as well as macro- and meiofauna were available from Project DIAGEN, from which this study is part. Bacterial density and biomass were always higher in Ubatuba bay, which appeared to be related to larger amounts of total organic matter, chlorophyll-a, pheopigments and microbial biomass. The differential deposition pattern observed in both bays was probably important determining the higher values of bacterial biomass and density found in the central and shallow portions of the bays. Despite higher bacterial density and biomass were found during the winter (June 2004) in most stations, this seemed not to be related to total organic matter or chlorophyll-a. Bacterial activity was high in surficial sediments, especially during autumn, with consistently larger values in Fortaleza bay.
ASSUNTO(S)
enseada de ubatuba benthic bacteria coastal sediments áreas costeiras enseada de fortaleza bactérias bênticas qualidade da matéria orgânica fortaleza bay. organic matter quality ubatuba bay
Documentos Relacionados
- Variações na acumulação de matéria orgânica, ao longo do holoceno, em sedimentos da região costeira de Ubatuba-São Paulo
- Etnoictiologia de pescadores artesanais da Vila de Picinguaba, Ubatuba, São Paulo
- Low-frequency physical variations in the coastal zone of Ubatuba, northern coast of São Paulo State, Brazil
- Variations in the quatolnary sedimentation of the coastal embayments of the Ubatuba Region, state of São Paulo
- Dinâmica do acoplamento bento-pelágico na plataforma interna ao largo de Ubatuba (São Paulo, Brasil)