Long-Term Effect of Prescribed Burning Regimes and Logging on Coarse Woody Debris in South-Eastern Australia

Abstract

Coarse woody debris (CWD) is vital within forest ecosystems for an array of fauna. Forest management practices, such as prescribed burning and logging, influence the creation or loss of CWD. We examined the effect of long-term prescribed burning and logging on (i) the abundance of hollow-bearing CWD, (ii) the volume of CWD in different decay classes, (iii) the probability of hollow presence, and (iv) the size of hollows at a long-term (28 years) experimental site. Volume of CWD in moderate and advanced stages of decomposition decreased with increasing fire frequency while moderately decomposed material was higher in logged plots. The likelihood of a hollow being present increased with diameter and decreased when CWD was extensively charred. Hollow size was smaller when material was externally charred but larger when charring affected a pre-existing hollow. Increases in moderately decayed CWD reflect a pulse input of unmerchantable timber following the one-off logging event 28 years ago, though future loss of mature trees may lead to reduced input rates of woody debris in the future. Charring effects on hollow formation, increasing hollow size but decreasing overall presence, demonstrate the complex effect of fire on this resource. Our research highlights the need to develop a fundamental understanding of CWD input and loss dynamics in response to fire and logging in order to predict changes to this resource under a broad range of management scenarios.

Keywords

• hollows
• cavities
• logs
• fire frequency
• temperate eucalypt forest
• logging