Evaluating Global Positioning System Accuracy for Forest Biomass Transportation Tracking within Varying Forest Canopy

We examined the accuracy and reliability of consumer-grade global positioning system (GPS) receivers for tracking vehicles transporting forest biomass within several forested road systems. The road systems featured a range of forest canopy types on mountainous terrain. GPS receiver measurements were clearly influenced by forest canopy and varied among the receivers. Under mature forest canopy, the best average measurement accuracy was 5.9 m for one set of GPS receivers. The least favorable average accuracy in mature forest was 14.3 m for a different set of GPS receivers. Measurement accuracies generally increased on roads that featured less forest canopy, with considerable increases in accuracy in some cases. The consumer-grade GPS receivers we tested provided measurement accuracies that support forest biomass transportation applications, including transportation monitoring and planning, mapping forest road networks, and cataloging forest resource locations.