Simulating options for carbon sequestration through improved management of a lowland tropical rainforest

Trade-offs between the two management criteria and cost-effectiveness of carbon sequestration were evaluated for alternative felling cycles, diameter cutting limits, and adoption of reduced impact logging methods. Simulations were driven by a growth model calibrated with data from a 50 hectare demographic plot in Peninsular Malaysia. This plot defined the initial state for all simulations. From a financial point of view, under any scenario, felling all valuable trees proved superior to a selective cut with a diameter limit. Lengthening to 50-60 years the current customary felling cycles of 30 years was desirable since it did not affect financial returns, while it increased carbon storage in the stand. The additional amounts of carbon sequestered per hectare by lengthening the felling cycle are, however, small. Net carbon sequestration could also be increased by reducing logging damage. The cost-effectiveness of this approach depended primarily on the incremental cost to achieve such damage reduction. If logging damage was reduced from 40% to 15% at an additional cost of about $150/hectare, carbon sequestration could be increased at a cost of only $3-5 per ton. However, findings suggest that there is no financial incentive in current management practices to reduce logging damage. In the absence of regulations and/or other forms of economic incentives, harvesting practices will continue to reduce net carbon sequestration. (Author abstract, modified)