Automated Tree (Hugging) measurements
Daily or weekly measurement of tree circumference growth yields insights into the seasonality of carbon accumulation and CO2 exchange in forests and can be measured using automated precision dendrometer bands (Zweifel et al. 2010). Because of the tight coupling between tree diameter at breast height (DBH) and total tree mass (Jenkins et al. 2003), measuring the change in stem circumference can be used to estimate carbon allocation to woody growth of trees on the ecosystem level (NPP_wood; Stenzel, J. et al., in review). A combination of self-reporting, wireless dendrometer bands (TreeHuggers) that report half-hourly stem wood growth and expansion, traditional manual dendrometer bands, and sap flow sensors (Granier et al. 1996) have been placed on over 100 trees at the UI experimental forest. Pre- and post-plot biomass, carbon, and nitrogen pools (including soils) are being measured using standard protocols established in the region (Hudiburg et al. 2009).