Zooplankton als Bioindikator für Umwelt Qualität in der Tamandaré Riff System (Pernambuco - Brasilien): Anthropogene Einflüsse und Austausch mit Mangroven

Abstract

Zooplankton studies carried out in the Tamandaré Bay (Brazil) were aimed at elucidating the role of bioindicators of anthropic impacts, mangrove on zooplankton production, and to see how nutrients, temperature, salinity, dissolved oxygen and seasonal patterns affect the zooplankton community in the reef area. In general the total productivity was high during the rainy and dry season. Copepoda and copepods nauplii emerged as the most dominant groups forming up to 80% of total zooplankton at mangrove area, and about of 70% and 60% of total zooplankton at non- and urbanized area. Oithona hebes, Oithona nana, Oithona oswaldocruzi and Parvocalanus crassirostris were the dominant and most abundant taxa. Holoplankton groups dominated the samples making about of 90% of total zooplankton groups. Other important groups which occurred frequently were Foraminifera, Tintinnina, and also fish eggs and larvae, other Crustaceaa and Molluscan larvae. Taxonomic abundance and spatial distribution of zooplankton are analysed in the two zones of the reef complex, as well as in the mangrove area; ecological subsystems are delimited and exchanges between them are explicited. Bioindicators of anthropic impacts (Rotifera and Nematoda) are very found at the urbanized area of Tamandaré coast, where the nutrients concentrations were also higher. This is an indication of organic pollution in the reef area, through the Maceió River. This river has high densities of Rotifera and Nematoda, and only Polychaeta larvae, Oithona hebes and copepods nauplii were also found in the sample from this river. It suggests that the reef in front of the Tamandaré urban area is a "impacted sector" of the Tamandaré reef complex. Moreover, the mangrove area is a important source of species and biomass, once the dominant and more abundant identified groups have mangrove origin. Zooplankton species diversity index revealed high diversity in mangrove and coral reef stations respectively