We investigated the vegetation of two active floodplains and associated stable landforms over a period of seven years, paying particular attention to the types of soil surfaces on which the plants grew. Long -lived trees were established on stable surfaces laid down in 700 -year -old superfloads and during much older activity. Less stable surfaces supported shorter - lived trees and shrubs, while the most active surfaces were entirely treeless. Many pasture species also showed preference for particular erosional surfaces. For example, the presence of Sclerolaena bicornis distinguished active floodplains from stable sand sheets, while S. divaricata separated severely eroded from less damaged floodplains. The dynamics of pasture composition over the seven -year period were also different for contrasting surfaces. Interestingly, erosion of stable surfaces did not change pasture dynamics until the subsoil became exposed. Regardless of surface type, changes in species composition brought about by major rainfall persisted for several years. We could not detect any impact of grazing cattle on pasture composition over time, despite independent evidence of grazing patterns in the area.
HOW EROSIONAL HISTORY AFFECTS THE DEVELOPMENT OF PASTURE AND SCRUB - A CENTRAL AUSTRALIAN CASE STUDY
Australian Rangeland Society
6TH Australian Rangeland Society Conference