Are soil and vegetation responses to precipitation changes coupled?

Droughts and extreme precipitation alter soil and vegetation functions, but the joint responses of these two ecosystem components are not well understood. To assess how much soil and vegetation responses to precipitation changes are coupled, we collated data from more than 150 precipitation manipulation experiments where both soil (carbon and nitrogen contents, microbial biomass, respiration) and vegetation responses (biomass, nutrient contents, productivity, respiration) were assessed. We found that soil and vegetation responses were sometimes coupled, while often only soil or vegetation responded. If responses were coupled, drought tended to reduce, and increased precipitation enhance, both soil and plant storages and fluxes. In addition, drought and increased precipitation changed more often vegetation and microbial biomass than soil organic matter pools. Several response combinations were underrepresented, indicating a knowledge gap that we need to fill to quantify the coupling of different ecosystem components in the face of extreme events.