Across the world, an estimated 1 billion acres of forests are in need of restoration right now, a formidable challenge that will only intensify under continued climate change. Where to start in restoring the world’s forests? What methods are appropriate? Restoring forests, already a complex process, is further complicated—and sometimes stymied—by a basic lack of consensus on what restoration means.
To provide managers with a better understanding of restoration and the factors to consider when planning forest restorations, U.S. Forest Service researchers synthesized the current thinking and available science in two journal articles that explore the paradigms underlying contemporary approaches to forest restoration and outline restoration strategies around specific methods and tools.
“Restoration is the reversal of degradation, so we looked to the definition of degradation for our starting point,” said John Stanturf, Forest Service Southern Research Station senior scientist who led the synthesis effort. “We decided that a broad definition fits best: a degraded forest has diminished capacity to supply goods and services, whatever the causal agent. Degradation can also be seen as the decreased capacity for resistance or resilience when disturbed.”
Forest restoration is needed to reverse degradation, but what is the ultimate goal? In North America, the ending point for restoration has often been seen as an idealized natural forest where there’s been no human influence, but humans have played a part in the disturbance regimes of forests worldwide for tens of thousands of years. Paradigms for restoration have shifted over the years from returning forests to a largely unknowable original condition to restoring function, most recently with the inclusion of human activities and needs. In the first synthesis article, the researchers map out four restoration paradigms:
- Revegetation describes early restoration efforts that focused on planting trees or other plants to restore productivity or stop soil erosion without regard for nativeness of species or structural diversity. Early tree plantings on the ruined soils of the South are an example of this.
- Ecological restoration is mostly site-level restoration focused on assisting the recovery of an ecosystem that’s been degraded, damaged, or destroyed, and includes specific goals for composition and structure often based on historic conditions. Stand-level longleaf pine restoration is an example, where the intent is to return to a forest ecosystem that once existed on the site.
- Forest Landscape Restoration (FLR) differs from site-level restoration in seeking to restore ecological processes that operate at larger landscape-level scales, and in incorporating human activities and needs. Current community forestry projects across the world focus on the human dimension of restoration and conservation.
- Functional restoration emphasizes the restoration of abiotic or non-living processes (water and soil chemistry and temperature, for example) and biotic processes regardless of structure. For example, introducing prescribed fire back into a longleaf pine forests where long-term fire suppression has allowed a hardwood mid-story to develop.
Part 2 of “Restoring Forests” focuses on four major approaches for altering structure and composition in degraded stands from a functional and landscape perspective.
For more information, email John Stanturf at firstname.lastname@example.org