Low-impact harvesting entails harvesting methods that are developed and executed to provide minimum disturbance to soil, remaining vegetation, and extracted trees. The practice influences the carbon stock change from trees left in the forest after harvest, as well as the growth (and corresponding carbon storage) of new trees and vegetation. It also influences carbon storage in end products by influencing timber quality and affecting the type of utilization that can be made of the timber.
Use and Potential
Winjum et al. (1998) estimate regional and global harvest volumes and corresponding carbon storage and emission changes. Putz and Pinard (1993) and Pinard and Putz (1996, 1997) demonstrate that reduced-impact logging is an activity that substantially decreases the emission of carbon in tropical forests because of reduced damage to soil and remaining trees.
Uncertainties associated with this practice relate to quantification of differences between carbon stock changes associated with better practices compared to those normally applied in a country or region. Estimates are needed of damage to soil, remaining trees, and other vegetation and the consequences of these damages for carbon stocks. In addition, regarding damage on extracted trees, estimates of the decay time of end products into which harvested timber is manufactured are needed. None of these measurements are included in the present IPCC methodology. Compiling results from several measurements in different forests may make possible the development of benchmarks for typical high-impact logging in different forest types and economies.
Monitoring, Verifiability, and Transparency
If the uncertainty factors are adequately met, monitoring and verifying this practice should be possible. Assumptions and methodologies associated with this practice are easily explained for replication and assessment of impacts.
In most cases this practice will have positive environmental benefits regarding biodiversity, recreation, and landscape management; no associated environmental damage is likely. In addition, this practice is likely to increase the economic value of remaining trees, as well as logged trees. Boscolo et al. (1997) estimate the cost efficiency of reduced-impact harvesting in a lowland tropical rainforest in Malaysia as $5.5 t-1 C. No conflicts are likely. The equity implications are small. The main barrier that prevents these activities from being implemented is lack of economic incentives. Without some incentives based on carbon impacts, costs are likely to remain higher than benefits.
Relationship to IPCC Guidelines
See Fact Sheet 4.12.
Other reports in this collection