Tools for restoration ecology
A challenge for restoration ecology is to develop theory that guides successful site-level outcomes. One approach to strike this balance is by testing general principles in collaboration with practitioners and in actual restoration projects.
Threshold models for restoration
A general principle of restoration ecology is to identify and reverse “thresholds”—levels of degradation that alter a system to the extent that it cannot recover without intervention. Thresholds can be abiotic (e.g., reduced water availability), or biotic (e.g., introduction of non-native species that suppress native species). After identifying thresholds, practitioners may alter them directly (e.g., irrigate; remove nonnative species) or restore species that can survive modified conditions (e.g., drought-tolerant species; good competitors).
The focus of my masters thesis, advised by Professor Richard Hobbs and Dr. Rachel Standish, was to identify and overcome thresholds to woodland restoration in post-agricultural lands. We worked with the Western Australian Department of Environment and Conservation and an NGO, Greening Australia, to monitor thresholds at ongoing restoration sites. High-summer drought mortality was a primary barrier to restoration success, especially in areas with sandy soils. However, we found that planting species with key traits – such as large seeds – could help increase survival in these areas.