IEA project Site productivity impacts of intensified biomass recovery

The global move towards sustainable energy solutions to reduce reliance on finite fossil fuel energy sources and greenhouse gas emissions, is driving demand for biomass from a wide range of sources, including forest biomass. The greatest opportunity for increased supply of forest biomass is from forest harvesting residues (Long & Boston, 2013). This is especially true in Australia, as only a small proportion of the millions of tonnes of residues produced per annum is currently utilised (Lock & Whittle, 2018).

Past “clear and burn” silvicultural practices that almost completely removed above ground biomass have demonstrated site productivity losses, in some cases catastrophic, particularly on low fertility sites, as compared to removal of stem wood products only (Isaac & Hopkins, 1937; Woods, 1990). Concerns have subsequently been raised about potential productivity impacts of any forest biomass removals additional to log harvesting (Egnell & Valinger, 2003; Nambiar, 1996). With limited understanding of where critical points are on how intensive a biomass recovery plantation managers can carry out while sustaining long-term site productivity, forest managers tend to be conservative with the intensity of forest biomass recovery, limiting biomass availability at scale.

IEA project Site productivity impacts of intensified biomass recovery