Histological and ultrastructural techniques in plankton ecophysiological studies [Tecnicas histologieas e ultraestruturais em estudos de eeofisioiogia planctonica]

Abstract

This study is part of a multidisciplinary and integrated project over the Mondego Estuary-Portugal, which aims to estimate the impact of the anthropic effects and natural forcing in the energy and matter circulation. The main objective is the characterisation of the different pelagic groups in its taxonomic, trophic and ecological components. Trough this is meant to evaluate the environmental impacts in the structure and functioning of the pelagic ecosystem, leading to the development of conceptual tools and guiding lines for the integrated and sustainable management of the estuarine ecosystem. The application of histological and electron microscopic techniques to key species of the zooplankton, besides the innovation that represents in itself, is of the greatest importance, once we take in consideration that the internal organisation of the organisms constitutes a reliable indicator of the influences environment bestows upon the functioning and behaviour of ecosystems. The methods here described allow the identification of anomalies/pathologies in various organs of zooplanktonic organisms and their connection with anthropic activities present in the estuary. These techniques act as a complement to the information obtained by the biochemical composition analysis of these key species allowing the schematic representation and modelling of the systems.