Statistical implications of end-point selection and inspection interval in the Daphnia reproduction test -- a simulation study
- Aachen Univ. of Technology (Germany)
In order to protect an ecosystem against anthropogenic stressors such as xenobiotics, potential impacts on its sensitive populations must be investigated. A general simulation approach was developed for validating biotest end points in the Daphnia reproduction test. Various toxic-effect scenarios, sample sizes, and inspection regimes were used to study the behavior and robustness of different end points. The intrinsic rate of natural increase (IR) and the capacity for increase (CI) were estimated because of their ecological significance. Both parameters were compared to conventionally chosen end points, the offspring number per female (ON) and the percent mortality (MO). The IR appeared to be the most sensitive end point among the different toxic-effect scenarios. In particular, effects on the age at first reproduction, which are highly relevant in population dynamics, were integrated. In general, the CI was as sensitive as the IR. However, the CI tends to overestimate the first brood. In contrast to ON and MO, both the IR and CI responded sensitively to the inspection regime. The IR was found to require daily recording if reproduction and mortality events, at least until the first broods appeared. Whereas the value of the CI remained questionable, from a statistical and ecological viewpoint the IR appeared to be superior.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 474303
- Journal Information:
- Environmental Toxicology and Chemistry, Vol. 15, Issue 10; Other Information: PBD: Oct 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Environmental Impacts of Wind Power Development on the Population Biology of Greater Prairie-Chickens
Effects of development mode, contaminated sediments, and maternal characteristics on growth and reproduction in the polychaetes Streblospio benedicti (Spionidae) and Capitella sp. I (Capitellidae)