| Инд. авторы: | Stampfli N.C., Knillmann S., Liess M., Noskov Y.A., Schafer R.B., Beketov M.A. |
| Заглавие: | Two stressors and a community - Effects of hydrological disturbance and a toxicant on freshwater zooplankton |
| Библ. ссылка: | Stampfli N.C., Knillmann S., Liess M., Noskov Y.A., Schafer R.B., Beketov M.A. Two stressors and a community - Effects of hydrological disturbance and a toxicant on freshwater zooplankton // Aquatic Toxicology. - 2013. - Vol.127. - P.9-20. - ISSN 0166-445X. - EISSN 1879-1514. |
| Внешние системы: | DOI: 10.1016/j.aquatox.2012.09.003; PubMed: 23063066; SCOPUS: 2-s2.0-84872178377; WoS: 000314623100003; |
| Реферат: | eng: Climate change models predict an increase in the frequency and intensity of extreme fluctuations in water level in aquatic habitats. Therefore, it is necessary to understand the combined effects of hydrological fluctuations and toxicants on aquatic biological communities. We investigated the individual and combined effects of the insecticide esfenvalerate and recurring fluctuations in water level on zooplankton communities in a system of 55 outdoor pond microcosms. The communities were exposed to esfenvalerate contamination as a single pulse (at 0.03, 0.3, or 3 μg/L) and gradual removal of water and its subsequent replacement over three cycles and monitored until 84 days after contamination. The results showed that the sensitivities of the community and its constituent populations to the toxicant were increased by the hydrological stress. Specifically, for both the community structure and abundance of Daphnia spp. the lowest-observed-effect concentrations (LOEC) were 0.03 and 0.3 μg/L for the series with fluctuating and constant water levels, respectively. Despite these differences in sensitivity, the interactive effects of the two stressors were found to be additive for both the community structure and the abundance of the most affected species. Presumably, it was not possible to detect synergism due to the strong individual effects of the water level fluctuations. Recovery times in the series exposed to the highest pesticide concentration were 64 and 55 days under fluctuating and constant water level regimes, respectively. Competition and water quality are suggested to be the major factors that underlie the observed effects of fluctuations in the water level. For the ecological risk assessment of toxicants, the present results suggest that (i) community sensitivity may vary substantially, depending on the environmental context, and (ii) this variability can be assessed experimentally to derive safety factors (coefficients used to avoid unexpected effects and define safe concentrations of toxicants) based on empirical findings. This contrasts with the current approach where such factors are usually defined arbitrarily. © 2012 Elsevier B.V.
|
| Ключевые слова: | Zooplankton; Water Pollutants, Chemical; Water Movements; Pyrethrins; Population Density; Nitriles; Fresh Water; Biodiversity; Animals; zooplankton; water quality; water pollution indicator; water pollution; water cycle; water contamination; surface water hydrology; sensitivity analysis; priority journal; population abundance; pond; pollution monitoring; nonhuman; microcosm; microbial community; freshwater species; freshwater environment; ecotoxicity; Daphnia; controlled study; concentration (parameters); competitive behavior; community structure; article; zooplankton; water quality; water level; synergism; pyrethroid; mesocosm; insecticide; hydrology; competition (ecology); community structure; climate effect; aquatic ecosystem; abundance; fenvalerate; Daphnia; Multiple stressors; Mesocosm; Ecological risk assessment; Community-level effects; Combined effects; Pyrethroid pesticide; |
| Издано: | 2013 |
| Физ. характеристика: | с.9-20 |