The sustainable management and use of aelolian derived landscapes in south-eastern Australia
Retired, Mildura Victoria, Australia
The aeolian derived landscapes of south-eastern Australia have been used for commercial agriculture for 150 years. This is a brief time in the context of the occupation of the area by indigenous people that has extended over 60 000 years or more.
The objective of the Paper is to provide an overview of the progression of the use and management of these aeolian derived landscapes. It will describe the modification of farming practices to address the problems of soil erosion and salinity. It will also discuss the actions of government in the context of the original alienation of the natural environment and its role in resuming and rehabilitating landscapes where farming failed.
The progression of alienation through to the present sustainable practices necessitated the development of land management practices that balanced the capability of the landscape, climate and economic pressures.
The aeolian landscapes of North-west Victoria were systematically described and mapped from the 1950’s onwards, and the information flowing from that systematic approach remains relevant. Landscapes were described at four levels; Land -zone, Land-system, Land- unit and Land-component. The Land-components, being the basic mapping unit, were described within defined limits. Repeat groupings of Land-components were mapped at the higher level of Land-systems.
The outcome of this assessment provided a very strong and systematic understanding of the capability of the land in the context of the climate and its variability. The mapping of the landscape at the Land-system level took account of the distribution and grouping of dunes, jumbled dunes and ridges. The surface materials range in texture from sands to clays, with soil texture being the dominant variable for mapping purposes. As aeolian derived soils often exhibit large variations both spatially and vertically it is necessary to target management actions to the land-component level.
The Paper will provide examples of how the use of derived knowledge has led to improvements in productivity whilst addressing problems of wind erosion, poor soil fertility and salinity. The importance of appropriate monitoring and reporting tools appropriate for variable landscapes is discussed.
Information in now being gained from remote sensing and focused surveys. This information is being applied at the farm management level for dryland cropping and for irrigation, utilizing geographic positioning capability.
The need to adapt to climate change has been recognized for the past 2 decades and some key actions to adapt to climate change are being successfully adopted. A sound understanding of the capability of the land is important in developing responses to changes in climate.
Examples of the rehabilitation of land previously used for agriculture and now managed for conservation purposes are described and discussed.