Indicators of chemical stressor levels derived from population time series: a retrospective modeling approach

摘要

Transient and asymptotic behavior of a physiologically structured, chemically stressed, individually based Daphnia population method developed for assessment purposes is investigated. An analysis employing this model as a foundation is performed to determine indicators for the magnitude of chemical stress. Using summary statistics, such as total popualtion biomass and total population size time-series data, various approaches, including dynamical systems methodology and a technique based on the mean and variance of total population biomass, were used to generate indicators from these data that could specify the concentration of chemical producing the observed Daphnia population dynamics. In this model setting, only the last approach exhibits promise for identifying indicators of chemical stress.