Distribuição espacial e temporal do fitoplâncton da Baía de Guanabara (RJ) definida por estratégias funcionais

Abstract

The Guanabara Bay is located in the metropolitan region of Rio de Janeiro and it is an estuarine environment that receives in natura sewage, industrial waste, among others discharges. The eutrophication resulting from anthropic activities influences the system s productivity, since there is an increase of phytoplankton biomass. The high species diversity, often observed in phytoplankton, shows frequent patterns that are expressed by adaptations in the morphology and physiology of the most ecologically successful species. Have been collect samples montly from April 2016 to April 2017, distributed in six stations: entrada, Urca, central canal, interior, Caju and Paquetá. The Guanabara Bay shows a spatial heterogeneity, with environments impacted by the influence of the drainage basin, and the entrance of seawater influences places with clearer and turbulent waters, which define nutrient gradients, salinity and turbidity. Besides, of a heterogeneous spatial pattern defined by gradients, a temporal pattern has been also observed associated with the influence of ACAS, temperature and rainfall currents that determine phytoplankton responses that have been analyzed from survival strategies. The CSR sensu Reynolds adaptive strategies associate the shape and metric characteristics of phytoplankton cells with their ecological strategies. The system proposed by Kruk recognizes functional traits, organized in a system based on the morphology of the individuals (GFBM) creating functional groups, while the proposition of Chen s functional groups (GFBMR) incorporates the separation of some groups of GFBM for a better elucidation of the species frequently found in rivers (Diatoms and Dinoflagellates), which are the same large groups found in estuaries. The use of the CSR strategies and the GFBM and GFBMR help in the interpretation of the quantitative and qualitative patterns of the phytoplankton and the interaction of the individuals with the environment. The CSR strategy has been defined throughout the study, exhibiting intersections between them and ecological strategies' plasticity of bay's phytoplankton. The GFBMR group approach showed an interesting relationship between the groups and Guanabara Bay, which has been able to evidence the diversity of the functional composition of phytoplankton and its responses to the factors that determine spatial and temporal gradients in the bay