摘要
The frequency and duration of droughts are predicted to increase with global warming, increasing the risk of wildland fires. This motivates research into how drought interacts with management practices to control fires, especially in non-target ecosystems. Fire-retardant chemicals help prevent or control fires, but adversely affect the natural (pristine) ecological status in aquatic ecosystems. Using a multiple before-after control-impact design, and univariate and multivariate statistics, this study assesses population- and community-level responses of zooplankton to the single and compounded effects of drought and contamination in experimental field mesocosms. The contamination treatment simulated real scenarios of dosage-dependent fire-retardant pollution. Drought and contamination interacted in ways that caused complex synergistic or antagonistic responses in zooplankton. Response patterns differed between population-level and community-level assessments. Also, zooplankton population responses to drought and contamination impacts were context specific. This study provides an example of a management dilemma for areas affected by droughts. Not only will drought increase the risk of wildland fires but also complicate the prediction of ecological impact in aquatic environments when using retardant chemicals as a fire control and mitigation option. Management trade-offs are needed to minimize the uncertainties related to ecological damage from wildland fires and protect valuable but scarce water resources.