Contrasting effects of organic and inorganic toxicants on freshwater periphyton.

摘要: This study analyses the factors influencing response of periphyton communities to toxicants in order test validity short-term physiological method. The effects two model compounds, atrazine and zinc, on photosynthesis from different lotic systems were analyzed using toxicity tests. Periphyton seven sites belonging a relatively small area used explore ecological parameters affecting flowing waters. Furthermore, time course studies zinc intact suspended carried out evaluate significance structure (thickness) toxicity. Atrazine varied slightly (0.42–2.42 μM) tests with as an endpoint. Only environmental light was detected lead systematic changes sensitivity field collected communities. In contrast, range EC10 values for very broad (7–>1000 μM), mainly related algal biomass, while also water chemistry (alkalinity) important. results time–course experiments indicated that penetration into thick biofilms limited. compounds tested present may exemplify situations. case atrazine, effect is easy predict here. On other hand, assessed much affected by many biological chemical variables. It concluded metals organic inorganic should be based longer times exposure.