Global meta-analysis shows that climate and land use disturbances
increase forest soil CO2 efflux
Abstract
Forest soil CO2 efflux (FCO2) is a
crucial process in global carbon cycling; however, how
FCO2 respond to disturbance regimes in different forest
biomes is poorly understood. We quantified the effects of disturbance
regimes on FCO2 across boreal, temperate, tropical, and
Mediterranean forests based on 1240 observations from 380 studies.
Globally, FCO2 was increased by 13 to 25% due to
climatic perturbations such as elevated CO2
concentration, warming, and increased precipitation.
FCO2 was increased by forest conversion to grassland and
elevated carbon input by forest management practices but was reduced by
decreased carbon input, fire, and acid rain. Disturbance also caused
changes in soil temperature and water content, which in turn affected
the direction and magnitude of disturbance effects on
FCO2. Our results suggest that disturbance effects on
FCO2 should be incorporated into earth system models to
improve the projection of feedback between the terrestrial C cycle and
climate change.