An important study from the Australian National University (ANU) has found that forest land needs decades to recover from forest fires and logging – much longer than previously thought.
Principal researcher Elle Bowd from the ANU Fenner School of Environment and Society said the team found forest land recovered very slowly for years from this event – up to 80 years after forest fires and at least 30 years after logging.
"We found that natural and human disturbances can have long-term effects on forest soils that can affect plant communities and ecosystem functions," said Bowd, who is the lead author of the ANU team. Natural Geoscience paper.
Image: Dr. Elle Bowd
"We think forests can recover in 10 or 15 years, at most, after this kind of event," said Professor Lindenmayer from ANU Fenner Community and Environmental School.
"Nearly 99 percent of Mount Ash Victoria's forests have been cut down or burned in the past 80 years, so these forests face a big battle to restore themselves to their former glory."
The team collected 729 soil nuclei from 81 locations exposed to nine different disturbance histories in Victoria's Ash Mountain forest.
These forests produce almost all water for five million people living in Melbourne, storing large amounts of biomass carbon and supporting the wood, pulp and tourism industries.
"It is very possible that other forests in the world face the same big challenges in terms of land recovery after forest fires and deforestation," Bowd said.
"Soil temperatures can exceed 500 degrees Celsius during high intensity fires and can cause loss of soil nutrients.
"Logging can expose forest floor, compact soil, and change soil structure, reduce important soil nutrients. This decline is more severe in areas that experience a lot of fires and logging. "
Large and old trees in these forests take more than a century to recover from disturbances, and forest land may require the same time to be restored.
"To preserve the vital functions of land in the forest, land management and policies need to consider the impact of long-term disruption to forest land, and reduce future disturbances such as clear-cutting logging."