Coarse woody debris in relation to disturbance and forest type in boreal Canada

Abstract

We measured volume of coarse woody debris (CWD) in three mature forest types (conifer, mixed, and deciduous), and two disturbance types (burns and clearcuts, both formerly mixed forests) in a boreal landscape in northwestern Ontario, Canada. The CWD levels in mixed (160.80±15.43 m 3/ha) and deciduous (105.29±14.05 m 3/ha) forests were significantly higher than those measured in coniferous forests (17.81±4.64 m 3/ha). Deadwood in these mature forests was predominantly downed material (i.e. logs) from a range of sizes and decay states. One-year-old burns, previously of mixedwood composition, had significantly more CWD (342.61±60.60 m 3/ha) than mature mixed forests (160.80±15.43 m 3/ha) and recent clearcuts (111.97±35.14 m 3/ha). The CWD in burns was primarily standing deadwood in the early stages of decay, while the bulk of CWD in clearcuts was made up of small pieces of recently downed material. Our findings underline the differences between burns and clearcuts with respect to CWD dynamics. We note the implications of this for boreal wildlife.