VARIATION IN CADMIUM .UPTAKE, FEEDING RATE, AND LIFE-HISTORY EFFECTS IN THE GASTROPOD POTAMOPYRGUS ANTIPODARUM: LINKING TOXICANT EFFECTS ON INDIVIDUALS TO THE POPULATION LEVEL

摘要

A life-table response experiment was performed to investigate the effects of sediment-bound cadmium on individual life-history traits and feeding rates of four clones of Potamopyrgus antipodarum. Demographic effects were evaluated using a simple two-stage model to estimate population growth rate (λ). Decomposition analysis was performed to investigate the contributions of each of the affected life-history traits to the effects observed on λ, and elasticity analysis was applied to examine the relative sensitivity of λ to changes in each of the life-history traits. Interclonal differences in tolerance to sediment-bound cadmium were statistically significant but were within an order of magnitude.