Coarse woody debris dynamics in the southern Appalachians as affected by topographic position and anthropogenic disturbance history

We examined the influence of topography and anthropogenic disturbance associated with European settlement in the southern Appalachian Mountains of Tennessee on contemporary distributions of coarse woody debris in western Great Smoky Mountains National Park. Coarse woody debris (≥10 cm diameter) was sampled on 63 permanent 20 m × 50 m plots, which were classified into one of five anthropogenic disturbance history classes based on published accounts: concentrated settlement, corporate logging, diffuse disturbance, diffuse disturbance with large residual trees present, or primary forest (no documented history of anthropogenic disturbance). Former concentrated settlement areas contained significantly less down deadwood (DDW) than areas with a history of less intense disturbance (P < 0.05). Areas of primary forest contained more total (134.3 ± 56.9 m3 ha−1) and highly decayed (39.2 ± 16.2 m3 ha−1) DDW than areas with a history of anthropogenic disturbance prior to Park Service acquisition in the 1930s (87.1 ± 15.5 and 21.1 ± 5.3 m3 ha−1, respectively). Large diameter DDW was most abundant in primary forests (90.1 ± 46.0 m3 ha−1) and least common in forests with a history of concentrated settlement (7.3 ± 3.0 m3 ha−1). Within a disturbance history class, the greatest levels of DDW were found on more mesic sites and/or higher elevations. Our results suggest that areas with a history of anthropogenic disturbance may require well over a century to recover coarse woody debris distributions found in areas of primary forest.