COS 55-7
A global synthesis of belowground C responses to biotic disturbance: a meta-analysis
Climate change, especially extreme events, likely increase intensity and frequency of insect/pathogen outbreaks (referred to as biotic disturbance), which considerably affects plant ecophysiological traits and then ecosystem carbon cycle. However, little is known about how biotic disturbance quantitatively affect ecosystem carbon processes. We quantify effects of biotic disturbance on belowground carbon (C) dynamics at biome and global scales. The meta-analysis approach was used to examine the effects of biotic disturbance on 16 variables associated with belowground C processes from 64 experimental studies.
Results/Conclusions
Biotic disturbance significantly decreased litter mass, root biomass, and soil organic carbon (SOC) but increased microbial biomass, dissolved organic carbon (DOC), and soil respiration, resulting in the negative responses of net ecosystem exchange. Compared with the positive effects of other environmental changes, biotic disturbance negatively affected biomass and SOC but positively impacted DOC to greater extent. These results suggest belowground C processes are vulnerable in response to biotic disturbance and more research efforts are needed to improve the forecasting of C cycle-climate feedback.