The use of airborne laser scanning to develop a pixel-based stratification for a verified carbon offset project

This paper presents a pixel-based forest stratification method that uses both ALS and optical remote sensing data to optimally partition the variability across an ~10,000 ha forest ownership in Mendocino County, CA, USA. This new stratification approach improved the accuracy of the forest inventory, reduced the cost of field-based inventory, and provides a powerful tool for future management planning. This approach also details a method of determining the optimum pixel size to best partition a forest.The use of ALS and optical remote sensing data can help reduce the cost of field inventory and can help to locate areas that need the most intensive inventory effort. This pixel-based stratification method may provide a cost-effective approach to reducing inventory costs over larger areas when the remote sensing data acquisition costs can be kept low on a per acre basis.The world's forests are a critical sink of carbon dioxide [1]. It is estimated that forest degradation or destruction results in 6 to 17% of total anthropogenic CO2 emissions annually [2]. Because of the importance of forest ecosystems in adapting to and mitigating climate change, there are now many policy initiatives to preserve and restore forest ecosystems for a climate benefit [3,4]. Despite years of discussion however, policies to reduce emissions from terrestrial ecosystems have generally not been adopted. An exception to this is California's cap and trade system that will incorporate carbon offsets starting in 2012 (barring a legal challenge) - see [5].In part due to the dearth of climate change policies, a vibrant voluntary carbon offset market has sprung up centered around a suite of different carbon project standards [6-9], and managing forests for carbon offsets can provide an important income stream for landowners willing to undertake the costs and requirements of these standards. These standards all have slightly different requirements regarding how to quantify the amount of carbon offsets g