Direct and indirect effects of shifting rainfall on soil microbial respiration and enzyme activity in a semi-arid system

Shrub-dominated systems of southern California are predicted to experience higher interannual precipitation variability, promoting variation in soil moisture and changing community composition. Here, we tested the hypothesis that soil microbial responses to differing rainfall regimes would vary depending on litter input and associated quality; an interaction between direct and indirect effects of shifting rainfall quantity showing direct effects of altered precipitation through soil moisture and indirect effects resulting from shifting litter inputs.