More than 2 million hectares of forest and scrub land was burned during the 1997-1998 El Nino event. Satellite analysis of the 1997-1998 fires revealed that 80 percent of the fires could be linked to plantations or logging concession holders.
Forest fires remain a devastating phenomenon in the tropics. How the tropical rainforest may be recovered after fire damage has been a common concern.
Through studies on the forest structure, tree species diversity, tree species composition, and aboveground biomass during the first 7 years since fire in unburned, once burned and twice burned forest of eastern Borneo, Dr. Ferry Slik of XTBG and his cooperators determined the rate of recovery of these forests.
The observation result “Tree diversity, composition, forest structure and aboveground biomass dynamics after single and repeated fire in a Bornean rain forest” has been published in Oecoloia: DOI 10.1007/s00442-008-1163-2.
Borneo and Sumatra burn as forest fires rage
Abstract Forest fires remain a devastating phenomenon in the tropics that not only affect forest structure and biodiversity, but also contribute significantly to atmospheric CO2. Fire used to be extremely rare in tropical forests, leaving ample time for forests to regenerate to pre-fire conditions. In recent decades, however, tropical forest fires occur more frequently and at larger spatial scales than they used to. We studied forest structure, tree species diversity, tree species composition, and aboveground biomass during the first 7 years since fire in unburned, once burned and twice burned forest of eastern Borneo to determine the rate of recovery of these forests. We paid special attention to changes in the tree species composition during burned forest regeneration because we expect the long-term recovery of aboveground biomass and ecosystem functions in burned forests to largely depend on the successful regeneration of the pre-fire, heavy-wood, species composition. We found that forest structure (canopy openness, leaf area index, herb cover, and stem density) is strongly affected by fire but shows quick recovery. However, species composition shows no or limited recovery and aboveground biomass, which is greatly reduced by fire, continues to be low or decline up to 7 years after fire. Consequently, large amounts of the C released to the atmosphere by fire will not be recaptured by the burned forest ecosystem in the near future. We also observed that repeated fire, with an inter-fire interval of 15 years, does not necessarily lead to a huge deterioration in the regeneration potential of tropical forest. We conclude that burned forests are valuable and should be conserved and that long-term monitoring programs in secondary forests are necessary to determine their recovery rates, especially in relation to aboveground biomass accumulation.
Keywords Burned forest regeneration - El Nino drought - Fire damage - Pioneer species - Recruitment
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