Widespread forest disturbance from windthrow in central African rainforests
摘要
Natural disturbances are major drivers of tropical forest dynamics, yet their role in Central Africa’s old-growth rainforests, the world’s second largest tropical forest block, remains poorly quantified. Here we present the first regional assessment of windthrow, the uprooting or breakage of trees by wind. Using Landsat imagery from 2019 to 2020, we detected 74 windthrow events ≥30 ha, collectively affecting ~18,600 ha. These events were concentrated in eastern regions where mesoscale convective systems and extreme rainfall are most frequent. Sizes of windthrow events followed a Weibull distribution, with a single 3974 ha event accounting for one fifth of the total affected area. Event orientations aligned with prevailing storm outflows, and their timing coincided with peaks in extreme rainfall. For a subset of seven events with adequate temporal coverage before and after disturbance, near-infrared reflectance returned to pre-disturbance levels within months, indicating a rapid vegetation regrowth. Together, these findings show that windthrow is an important disturbance agent in Central Africa and must be considered in assessments of forest resilience under intensifying storm regimes.