Drivers of landscape change: Aaron Petty
Tropical savannas extend across nearly one third of the
Earth’s — and Australia’s — surface.
Although the biome is principally defined by a climate condition
— highly seasonal but regular rainfall patterns — the
name “savanna” is also given to the dominant feature of
tropical savannas: open woodlands characterised by the coexistence
of grasses and trees.
Under classical successional theory this is a paradox: either
conditions do not support trees, or trees eventually supplant
grasses. There has been much debate over the factors that lead to
grass-tree coexistence in savannas, but a consensus is forming that
disturbance, particularly from grazing and fire, is the key
structuring factor. Because tropical savannas are disturbance
dependent systems, they can be particularly impacted by seemingly
subtle changes in disturbance regime.
Landscape Change Slideshow
Slideshow of talk delivered by Aaron Petty to Savanna Futures Forum, February 28th, 2008, Darwin [pdf 4.1 Mb]
Landscape Change Summary
Summary of talk delivered by Aaron Petty to Savanna Futures Forum, February 28th, Darwin [pdf 15.1 kb]