Dataset for: The unexpected absence of nickel effects on a Daphnia population at three temperatures is correctly predicted by a dynamic energy budget individual-based model (DEB-IBM)

Recent studies have shown that temperature affects chronic Ni toxicity to Daphnia magna at the individual (apical) level. However, the effect of temperature on Ni toxicity to D. magna at population-level is unknown. The present study investigated whether the effect of temperature on chronic Ni toxicity to D. magna assessed on apical endpoints can be extrapolated to the population-level. The results of the performed population experiment showed no consistent Ni effects on total D. magna population abundance at 15, 20 and 25ºC although the Ni concentrations tested were previously reported to significantly reduce reproduction in D. magna individuals. This result supports the idea that ecological risk assessment should not extrapolate as such from apical endpoints to the population-level. A Dynamic Energy Budget Individual-Based Model (DEB-IBM) was calibrated using apical Ni toxicity data at 15, 20 and 25°C. The goal was to investigate whether the calibrated DEB-IBM would be able to predict the unexpected absence of effects at population-level and to further investigate the effect of temperature on Ni toxicity to a D. magna population. At the population level, the calibrated DEB-IBM correctly predicted the unexpected absence of Ni effect to a D. magna population. Extrapolated EC50 values for population density predicted that the effect of temperature on Ni toxicity to D. magna populations was smaller (1.9-fold higher at 25°C than at 15°C) than on Ni toxicity to D. magna apical reproduction (the EC50 is 6.5-fold higher at 25°C than at 15°C, previous study). These results show that the DEB-IBM can help to replace population experiments by in silico simulations and to optimize the experimental design of population studies.已有研究表明，温度会在个体（顶端）水平上影响镍（Ni）对大型溞（Daphnia magna）的慢性毒性。然而，温度对镍对大型溞种群水平毒性的影响尚不明确。本研究旨在探究：以顶端终点为评估指标得到的温度对大型溞慢性镍毒性的影响，能否外推至种群水平。本研究开展的种群实验结果显示，在15℃、20℃与25℃条件下，镍并未对大型溞总种群丰度产生一致影响；尽管此前已有研究表明，本次实验所用的镍浓度可显著抑制大型溞个体的繁殖能力。该结果佐证了这一观点：生态风险评估不应直接将个体顶端终点的结果外推至种群水平。本研究基于15℃、20℃与25℃下的镍顶端毒性数据，对动态能量预算个体模型（Dynamic Energy Budget Individual-Based Model, DEB-IBM）进行了校准。本研究的目标为：验证经校准的DEB-IBM能否预测种群水平上未出现预期毒性效应的现象，并进一步探究温度对镍对大型溞种群毒性的影响。在种群水平上，经校准的DEB-IBM准确预测了镍对大型溞种群未出现预期毒性效应的结果。外推得到的种群密度半数效应浓度（EC50）预测结果显示，温度对镍对大型溞种群毒性的影响较弱（25℃下的EC50仅较15℃高1.9倍），而温度对镍对大型溞个体顶端繁殖毒性的影响则更为显著（此前研究表明25℃下的EC50较15℃高6.5倍）。上述结果表明，DEB-IBM可通过计算机模拟替代种群实验，并助力优化种群研究的实验设计。