Measuring, monitoring, and verification of carbon benefits for forest–based projects

Abstract
Worldwide, there are many pilot forestry projects that are under some stage of implementation, and much experience has been gained from them with respect to measuring, monitoring, and accounting for their carbon benefits. Forestry projects have been shown to be easier to quantify and monitor than national inventories, partly because not all pools need measuring: a selective accounting system can be used that must include all pools expected to decrease and a choice of pools expected to increase as a result of the project. Only pools that are based on field measurements should be incorporated into the calculation of carbon benefits. Such a system allows for trade–offs between expected carbon benefits, costs, and desired precision, while maintaining the integrity of the net carbon benefits. Techniques and methods for accurately and precisely measuring individual carbon pools in forestry projects exist, are based on peer reviewed principles of forest inventory, soil sampling, and ecological surveys, and have been well tested in many part of the world. Experience with several forestry projects in tropical countries has shown that with the use of these techniques carbon stocks can readily be estimated to be within less than ±10% of the mean. To date, there is little experience with measuring the changes in carbon stocks over time but, using the correct design and sufficient numbers of permanent plots, it is expected that precision levels will be maintained at less than ±10% of the mean. Internal verification can be accomplished through use of quality assurance/quality control plans. External or third–party verification is still in its infancy, and would greatly benefit from international agreements in relation to protocols used for all aspects of project design and implementation.