This chapter is the first of two that justify the project. It begins to answer the question of why we did what we did by stating the nature of the problem that we addressed.
It is a reflection upon both the maturity of Australian society and on the nature of the principal issues that there is substantial and persistent public interest in the state of the environment: the well being of the entire Australian continent.
Three issues dominate contemporary public debate about the state of the nation's environment. They are: sustainable landuse, the loss of biodiversity, and the potential for climate change driven by the Enhanced Greenhouse Effect (EGE).
All three issues are perceived by the public and by policy-makers to be intimately related to the quality of life enjoyed by Australian society; see, for example Bridgewater (1994), Broome (1992), Cocks (1992), Roberts (1995).
All three issues contain considerable uncertainty:
Our basic proposition is that there is a thread that links all three issues. That thread is landcover; the cover of vegetation and soils.
Changes in landcover, in vegetation and in soils, usually have significant consequences for biodiversity, sustainable landuse, and for changing the greenhouse gas composition of the global atmosphere.
Therefore, a focus on landcover can contribute understanding to all three issues.
Landcover is another name for the land surface that is the boundary between the atmosphere and the lithosphere. For the Australian continent, it is predominantly vegetation and soils with a minor percentage of dry salt lakes. The landcover of very large areas of other continents consists only of snow and ice.
In this document we report the strategy and findings of an assessment that we made of landcover disturbance for the entire Australian continent.
The assessment had two objectives:
We believe the findings presented here will interest a wide audience because of their continental scope and currency: this is what the nation's landscapes are like, now.
What was achieved here was built on earlier efforts. In the same way, while we hope our undertaking will contribute to increased overall understanding, it is far from the last word and will also serve as a stepping stone for future efforts.
For example, within two years, we will publish our next step: a more finely detailed assessment of the landcover clearing rate over the last decade. Until these and other studies are completed, we offer this document as a contemporary mapping of the disturbance level of continental landcover, and an assessment of its consequences for biotic impoverishment, both existing and potential.
We have set ourselves the goal of undertaking a survey of the entire continent to examine the big picture. For the reader to begin to appreciate the spatial scales of this report we recommend that you examine this image of Australia and navigate your way around it using the geographic knowledge that you have.
This is a contemporary image of the nature and condition of the landcover of the entire continent. The ecological information that can be extracted from this image is both empowering and unique. For a continental assessment - the big picture - space data is a critical prerequisite.
