Friday, August 7, 2009: 8:20 AM
Cinnarron, Albuquerque Convention Center
Andrew E. Scholl, Geography, Wittenberg University, Springfield, OH and Alan H. Taylor, Geography Department, The Pennsylvania State University, University Park, PA
Background/Question/Methods Carbon dynamics in forested ecosystems are recognized as an important component of the global carbon cycle and are influenced by tree growth, regeneration and disturbance events. Fire suppression has altered forests through the process of woody encroachment and infilling, however few studies have been able to identify pre-fire suppression forest conditions in much detail and quantify changes in biomass and carbon sequestration over time. Using dendroecological techniques we developed a more complete estimate of carbon storage change using a detailed reconstruction of the pre-fire suppression forest including the incorporation of trees that have died since fire suppression. Using measured growth rates in the forest we also tracked the changes in carbon storage through the different storage components of the forest over 100 years. In addition, the reconstruction allows us to determine the relative impacts of infilling and forest encroachment on carbon storage.
Results/Conclusions
Total carbon increased significantly from an average of 222.7 Mg C/ha in 1899 to an average of 525.9 Mg C/ha in 2002. The majority of carbon was stored in trees between 80-130 cm dbh in both 1899 and 2002. Following fire suppression, the largest increase in carbon storage occurred in trees <50 cm, while the proportion of carbon stored in live trees >180 cm declined. However, dead trees >180 cm were still present in the study area and contained a larger proportion of carbon than live trees >180 cm. Carbon sequestration of live trees shifted from large trees in the pre-fire suppression forest, to mid-sized trees in the contemporary forest, while dead trees still present in the forest stored significant amounts of carbon.
