Lead Investigator: Dr Michael Franklin (WSU)

Co-Investigators: Dr Emma Gorrod (DCCEEW), Dr Laura White (DCCEEW), Dr Ian Oliver (DCCEEW), Associate Professor Paul Rymer (WSU) and Associate Professor Uffe Nielsen (WSU)

Project Summary: To support the persistence of Australian woodlands, conservation must be augmented with restoration of areas where these communities are degraded. However, restoration outcomes can be difficult to predict because historical efforts have achieved varied results, with little evidence of what enhances success, and the causes of failures are rarely widely disseminated. When the management aim is to restore a resilient native ecosystem, barriers to success, such as altered soil nutrient levels, require consideration. Restoration interventions are increasingly applied with this end in mind, but there is a need to consolidate the available information on the effectiveness of different interventions, to support project planning and adaptive management of ongoing projects. The aim of this meta-analysis was to gather and assess quantitative information on the responses of plants and soils to individual management interventions applied to restore degraded temperate and semi-arid woodlands in Australia. Planting trees and shrubs improved some ecological attributes compared with degraded areas, but soil phosphorous and exotic plants remained higher, and native plant responses were lower, than in intact reference systems. Results of interventions to remove biomass were mixed, in that burning promoted native plants and inhibited exotic plants, slashing promoted exotics over natives, and herbicide had mostly negative effects on both plant groups. Carbon addition to the soil surface increased native plant responses and had negative effects on exotics, while coarse woody debris addition improved soil conditions. These findings provide a basis for trialling interventions to achieve pre-defined and measurable ecological responses in an adaptive management context.