期刊
AQUATIC TOXICOLOGY
卷 106, 期 -, 页码 25-31出版社
ELSEVIER
DOI: 10.1016/j.aquatox.2011.09.012
关键词
Indirect effect; Intraspecific competition; Interspecific competition; Community; Daphnia magna; Culex pipiens
资金
- EU CREAM [PITN-GA-2009-238148]
- Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
We investigated how persistent competitive pressure alters toxicant sensitivity and recovery from a pesticide pulse at community level. Interacting populations of Daphnia (Daphnia magna) and Culex larvae (Culex pipiens molestus) were pulse-exposed (48 h) to the pyrethroid fenvalerate. The abundance and biomass of the populations were monitored by non-invasive image analysis. Shortly after exposure. Daphnia showed a concentration-response relationship with the toxicant with an LC50 of 0.9 mu g/L Culex larvae were slightly less sensitive with an LC50 of 1.7 mu g/L. For both species, toxicant sensitivity increased with the population biomass of the respective species before exposure, which is explained by intraspecific competition. Several weeks after exposure to the highest treatment concentration of 1 mu g/L, the slight differences in sensitivity between the two species were amplified to contrasting long-term effects due to interspecific competition: high interspecific competition impaired the recovery of Daphnia. Subsequently, Culex larvae profited from the slow recovery of Daphnia and showed an increased success of emergence. We conclude that, in natural systems where competition is present, such competitive processes might prolong the recovery of the community structure. Hence, natural communities might be disturbed for a longer period by toxic exposure than predicted from single-species tests alone. (C) 2011 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据