For decades, scientists believed cool temperate rainforests were fragile ecosystems easily damaged by disturbances like fires or logging. But new research from the University of Melbourne challenges this view, revealing how these ancient forests actually depend on disturbance for their survival.
The study focused on Nothofagus moorei, or Antarctic beech, a towering tree that forms the backbone of these ecosystems. The research team analyzed data from silvicultural experiments established in the 1960s across 15 plots in northern New South Wales. These experiments involved different levels of canopy removal, providing a unique opportunity to study how rainforest species respond to various disturbance intensities.
Using advanced statistical models, the researchers examined the growth rates of trees following disturbance, mortality rates in response to different disturbance levels, and the recruitment success of new trees. The findings found that N. moorei grew faster and recruited more successfully following higher disturbance intensities. Additionally, 60% of the 30 species examined could resprout after disturbance, highlighting the ecological resilience of cool temperate rainforests.
These discoveries have significant implications for conservation strategies. "Actively excluding all forms of disturbance may actually threaten the survival of species like N. moorei" explains Kate A. Simmonds, the corresponding author. "These forests need disturbance of some extents to maintain their ecological diversity".
As climate change intensifies fire regimes across Australia, the research suggests that managed disturbance regimes—rather than complete exclusion—could be the key to preserving these ancient ecosystems. The study not only advances our understanding of cool temperate rainforest ecology but also provides actionable insights for forest managers working to protect these ancient ecosystems in a changing world.
This work was supported by the Bushfire and Natural Hazards Cooperative Research Centre and New South Wales National Parks and Wildlife Service.
