Original landscape and causes of change
Original landscape
European settlement
Although some explorers noted that the area was covered in extensive grassy woodlands (eucalyptus), with an 'open park like' appearance (a grassy understorey), there are few records of what the landscape looked like prior to European settlement.
The region supported a hunter-gatherer Aboriginal population and Aboriginal burns may have kept tree species down to a low-level density and this use of fire probably maintained open grassy communities.
Since European settlement fire use has diminished in the area and grazing is now the major cause of disturbance resulting in low-density trees.
Vegetation composition and structure has been modified by
- sheep and cattle grazing
- use of fertilisers
- machinery induced soil disturbance
- altered drainage patterns
Increased stock intensity and the addition of exotic grass species has caused a reduction in native herbivores and an introduction of large feral herbivores, which have all impacted on the vegetation structure.
European settlement introduced exotic fauna species and novel disturbances, exogenous disturbances, which enhanced the invasion of exotic species and the replacement of native vegetation. Endogenous disturbance regimes, like Aboriginal use of fire, have also changed.
The grassy woodland matrix still exists in the landscape but this has become overlain by the effects of grazing, clearing, soil disturbance, nutrient and water enrichment and exotic species introduction, which have occurred at different spatial and temporal scales.
