Development of an integrative approach for the characterization of ecological risk on marine transition ecosystems: the Sado Estuary as a case study

Estuaries and other transitional waters are complex ecosystems critically important as nursery and shelter areas for organisms. Also, humans depend on estuaries for multiple socio-economical activities such as urbanism, tourism, heavy industry, (taking advantage of shipping), fisheries and aquaculture, the development of which led to strong historical pressures, with emphasis on pollution. The degradation of estuarine environmental quality implies ecologic, economic and social prejudice, hence the importance of evaluating environmental quality through the identification of stressors and impacts. The Sado Estuary (SW Portugal) holds the characteristics of industrialized estuaries, which results in multiple adverse impacts. Still, it has recently been considered moderately contaminated. In fact, many studies were conducted in the past few years, albeit scattered due to the absence of true biomonitoring programmes. As such, there is a need to integrate the information, in order to obtain a holistic perspective of the area able to assist management and decision-making. As such, a geographical information system (GIS) was created based on sediment contamination and biomarker data collected from a decade-long time-series of publications. Four impacted and a reference areas were identified, characterized by distinct sediment contamination patterns related to different hot spots and diffuse sources of toxicants. The potential risk of sediment-bound toxicants was determined by contrasting the levels of pollutants with available sediment quality guidelines, followed by their integration through the Sediment Quality guideline Quotient (SQG-Q). The SQG-Q estimates per toxicant or class was then subjected to georreferencing and statistical analyses between the five distinct areas and seasons. Biomarker responses were integrated through the Biomarkers Consistency Indice and georreferenced as well through GIS. Overall, in spite of the multiple biological traits surveyed, the biomarker data (from several organisms) are accordant with sediment contamination. The most impacted areas were the shipyard area and adjacent industrial belt, followed by urban and agricultural grounds. It is evident that the estuary, although globally moderately impacted, is very heterogeneous and affected by a cocktail of contaminants, especially metals and polycyclic aromatic hydrocarbon. Although elements (like copper, zinc and even arsenic) may originate from the geology of the hydrographic basin of the Sado River, the majority of the remaining contaminants results from human activities. The present work revealed that the estuary should be divided into distinct biogeographic units, in order to implement effective measures to safeguard environmental quality.

Marine toxins in bivalves: accumulation, kinetics and subcellular responses

Sociedade Polis Litoral Ria Formosa,Projects Quasus and Project Toxigest financed by PROMAR (2007-2013)

Marine Protected Areas (MPAs): Methodologies for assessment

Marine Protected Areas are an effective way of protecting biodiversity, with potential socio-economic benefits including the enhancement of local fisheries and maintenance of ecosystem services. However, local fishing communities often fear short-term revenue losses and thus may oppose marine protected areas creation. This work includes a review of the need of having management effectiveness evaluation and its importance in providing useful information for stakeholders. Therefore, evaluation methodologies are presented and assessed in order to suggest possible approaches to the Berlengas MPA. In this case, an indicator-based approach can be relevant as a starting point, providing already some insights about the management effectiveness of Berlengas MPA. It also supports the development of a more ambitious approach such as a bio-economic model.

Caracterização dos padrões de mortalidade e identificação dos pontos negros de mortalidade da fauna na A21

A monitorização da mortalidade da fauna nas estradas tem vindo a receber mais atenção no decorrer dos anos sendo uma temática em que ainda existe potencial para investigação assim como de propostas para medidas de mitigação. Em Portugal, os estudos mais desenvolvidos são geralmente realizados por concessionárias como a Infraestruturas de Portugal, a Brisa entre outras. Reconhece-se a importância desta temática devido aos impactes negativos a nível ecológico e ambiental resultantes da expansão da rede viária. Um fator agravante é a fraca sensibilidade dos condutores para a presença de animais na estrada e problemas devido às caraterísticas da estrada. Existem espécies que são atraídas para a estrada para se alimentarem da vegetação envolvente ou de cadáveres de outros animais, para realizarem a termorregulação ou por simplesmente precisarem de atravessar a estrada regularmente sendo por isso mais propícias a serem atingidas por veículos. A presença de animais na estrada pode acarretar riscos de acidentes assim como perdas humanas e financeiras. Deste modo, as concessionárias implementam estudos de monitorização da mortalidade da fauna nas estradas para perceberem os locais com maior número de atropelamentos, quais as espécies mais afetadas e assim conseguirem introduzir medidas de minimização que podem ser desde vedações a passagens próprias para a fauna. O objetivo deste trabalho consistiu na caracterização dos padrões de mortalidade e identificação dos pontos negros de mortalidade da fauna na autoestrada nº 21 (A21), bem como a sua relação com o habitat envolvente. Conclui-se que os animais mais afetados são os coelhos seguindo-se as cobras e as corujas e mochos. Através do buffer do habitat envolvente e do teste estatístico de Spearman não se conseguiu provar a influência do habitat envolvente sobre a mortalidade. Finalmente, foram propostas algumas medidas de minimização para os pontos negros identificados.