Wildfires deplete soil carbon for over four years
Burned chamise in Otay Mountain Wilderness Area, 2003.
Wildfires are becoming more severe and frequent and soil carbon is an important component of healthy forests. Yet, we do not have a good understanding about how severe fires affect soil carbon stocks. This is because in addition to directly depleting soil carbon through combustion, wildfires also affect the plant and microbial processes that control soil carbon accumulation. We found that microbial communities recovered more quickly than plants after the fire, which caused soil carbon pools to continue to decrease for one year after burning. However, plant recovery remained limited for 4 years after the fire, slowing the recovery of soil carbon pools. This finding suggests that promoting the recovery of native plant communities may be key to retaining soil carbon stocks in burned ecosystems.