Biodiversity is diminishing at alarming rates due to multiple
anthropogenic drivers. To mitigate these drivers, their impacts must be
quantified accurately and comparably across drivers. To enable that, we
present a generally applicable framework introducing fundamental
principles of ecological impact quantification, including the
quantification of interactions between multiple drivers. The framework
contrasts biodiversity variables in impacted against those in unimpacted
or other reference situations, while accounting for their temporal
dynamics through modelling. Properly accounting for temporal dynamics
reduces biases in impact quantification and comparison. The framework
addresses key questions around ecological impacts in global change
science, namely, how to compare impacts under temporal dynamics across
stressors, how to account for stressor interactions in such comparisons,
and how to compare the success of management actions over time.