PARENT SESSION
Poster Session #20: Arid Lands Restoration.
Tuesday, August 6. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Understanding an Australian semi-arid ecosystem: lessons for restoration of a National Park.

Page, Manda^*,1, ¹ The University of Queensland, Gatton, Queensland, Australia

ABSTRACT- Investigating the vegetation dynamics of an Australian semi-arid National Park has revealed insights for restoration and management. Currawinya National Park, situated in southwest Queensland, was proclaimed a National Park in 1992 following 150 years as a sheep station. Rainfall (<200mm/yr) is highly unpredictable both within and between years. The area is considered degraded (as is 2/3 Australian rangelands) with evidence of soil erosion, palatable perennial grass extinction and increased native woody shrub density. Vegetation monitoring and woody shrub removal experiments under three grazing regimes began in 1992. More recently fire experiments and seed bank investigations have been undertaken. The results indicate that vegetation dynamics is mostly dictated by the amount and timing of rainfall. However, total removal of mammalian grazing pressure has resulted in significant increases in the cover and diversity of perennial grasses while simply removing sheep only results in significant differences following good summer rainfall. The success of woody shrub control is negatively correlated with grazing pressure. The seed banks have not improved significantly after 8 years of destocking. As managers cannot manipulate the timing or amount of rainfall, this information indicates that total grazing pressure should be managed in order to gain the greatest restoration results. Without reducing grazing pressure, other strategies may be a waste of time.

KEY WORDS: Australia, Restoration, Semi-arid, National Park