Description: Das Projekt "Effekte von Nickel auf eine aquatische Lebensgemeinschaft in Mikrokosmen" wird vom Umweltbundesamt gefördert und von Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie durchgeführt. Quality standards to assess the chemical status of water bodies under the Water Framework Directive are often based on a few standardized laboratory tests and fixed assessment factors for extrapolation to the field situation. If larger data sets including tests with non-standard species are available, a statistical extrapolation approach, the Species Sensitivity Distribution approach (SSD) is applied. For assessing the remaining uncertainty on the SSD, the threshold concentration derived can be compared with data from field monitoring or model ecosystem studies. Taking the priority substance Ni as an example we present the use of microcosms to test the protectiveness of the quality standard derived from laboratory toxicity tests. The study was conducted in 14 microcosms including a natural sediment layer and an overlaying water volume of 750 L located in a greenhouse. After a pre-treatment period for establishing a diverse aquatic community of phytoplankton, zooplankton, periphyton and snails, Ni solution was added to reach concentrations of 6, 12, 24, 48 and 96 micro g Ni/L in two microcosms each. Four microcosms served as untreated controls. To achieve the intended constant exposure over the test period of four months, Ni concentrations were frequently determined in the microcosms and appropriate amounts of nickel solution were added mostly on a daily basis. Parameters known to affect Ni toxicity, i.e. water hardness, pH, and dissolved organic carbon, were also measured. Population abundance and community structure were analysed for difference to the dynamics in the controls. In the microcosms with 48 and 96 micro g Ni/L long-term effects on phytoplankton, rotifers, snails and, due to reduced grazing by snails, indirectly on the periphyton biomass were observed. Only minor, and/or temporary deviations from controls, i.e., for single sampling dates, were found for a few algae taxa at lower concentrations. Because these deviations showed no clear dose-response and were not found at the end of the study they were not seen as adverse effects. However, for the snail (Lymnaea stagnalis), effects on the trend of population development could not be excluded at 24 micro g/L. Thus, the overall No Observed Effect Concentration (NOEC) for a chronic exposure to nickel in this microcosm study was considered to be 12 micro g Ni/L. This NOEC confirms the protectiveness of the quality standard derived from the laboratory single species tests.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Populationsdynamik ? Nickel ? Schnecke ? Seen ? Abraum ? Periphyton ? Langzeitwirkung ? Phytoplankton ? Skigebiet ? Gewächshaus ? Zooplankton ? Molekularbiologie ? Chronische Exposition ? Gewässerbiozönose ? Demografischer Wandel ? Biozönose ? Datierung ? Kind ? Rädertierchen ? Wirkung ? Chemischer Zustand ? Wasserrahmenrichtlinie ? Prioritäre Stoffe ? Nil ? Gelöster organischer Kohlenstoff ? Laborversuch ? Studie ? Toxizität ? Grundwasserleiter ? Wasserhärte ? Hochrechnung ? Bevölkerungsstruktur ? Sediment ? Algen ? Beweidung ? Ackerland ? NOEL ? Aquatisches Ökosystem ? Wirkung ? Ökosystemmodell ? Chemikalien ? Daten ? Artenbestand ? Messung ? REACH ? Exposition ? Gewässerqualität ? Ökosystem ? Forschungseinrichtung ? Kenngröße ? Richtlinie ? Norm ? Schwellenwert ? Aquatische Biomasse ? KONTROLLE ? Konzentrat ? LOESUNG ? ORTSFEST ? PROBE ? UEBEREMPFINDLICHKEIT ? UNTERSUCHUNG ? VERFUEGBAR ? VERGLEICHEN ? VERTEILUNG ? Vorbehandlung ? ZEITRAEUME ? ANGEWANDT ? Art [Spezies] ? DATENSATZ ? DAUER ? GEGENWART ? GELOEST ? GEMEINSCHAFT ?
Region: Nordrhein-Westfalen
Bounding box: 6.76339° .. 6.76339° x 51.21895° .. 51.21895°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2009-01-01 - 2011-05-10
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