Nonylphenol (NP) has been known for long time as a suspected endocrine disruptor in animals. We have conducted an experiment to look at the effect of NP on the life-history of the parthenogenetic springtail, <i>Folsomia candida</i>. Six sub-lethal concentrations (0, 8,16, 24, 32, 40 mg/kg dry soil) were applied to 6 replicates of soil containing an individual of 0-1 day old juvenile. During continuous exposure (63 days), we assessed springtail life-history traits such as: survival, growth rate, molting time, time between molting, time to first reproduction, egg production, and viability in response to different concentrations of NP. The juveniles did not survive the highest concentration of the chemical. In linking the effects on individuals to the population level and for identifying which trait(s) was (were) responsible for the effect on l, we used a simple two-stage model to estimate population growth rate (l). Decomposition analysis to investigate the contribution of each of the affected life-history traits to the effects observed on l, and elasticity analysis to examine the relative sensitivity of l to changes in each of the life history traits provided valuable insight into the mechanistic basis of population-level effects of NP.
Folsomia candida; nonylphenol; population growth; elasticity
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Understanding the Complexity of Environmental Issues: A Way to Sustainability, 2003