Management trade-offs between forest carbon stocks, sequestration rates and structural complexity in the central Adirondacks

Managing forests for carbon sequestration is an emerging objective within forestry sectors, although considerable uncertainty remains about how best to influence forest C dynamics through silviculture. This study tests hypotheses regarding forest C management within the central Adirondacks and assesses management trade-offs between aboveground live tree C relative to forest structural and biological complexity. The effects of management on forest C stocks, sequestration rates and structural complexity were assessed using a multivariate metric of management intensity derived from historical harvest records, combined with forest inventory data collected from Huntington Wildlife Forest (Newcomb, NY) from 1970 to 2011. Management intensity was quantified using a principal component analysis on measures of management inputs (harvest duration, total harvest area, number of harvest entries) and outputs (harvested wood volume). The first principal axis was used as a unitless metric of management intensity, which explained 64.1% of the variation in management activity. As management intensity increased, above ground live tree C stocks significantly declined but C sequestration rates significantly increased. Management intensity was correlated with decreased structural complexity. Active management can increase forest C uptake through the distribution of resources to young tree cohorts within a stand, which is consistent with the hypothesis of the C stock-sequestration trade-off. However, structural complexity was significantly reduced in areas with the highest C sequestration rates. These trade-offs should be considered and balanced when implementing management that aims to improve the C storing potential of central Adirondack forests.