A Geomorphological Framework for Land and Soil Data -a Victorian Example.
David B. Rees1, Nathan J. Robinson1, and E. Bernie Joyce2. (1) Dept. Primary Industries, 40 Ballarto Rd, Frankston, 3199, Australia, (2) Dept. of Earth Sciences, Univ of Melbourne, Grattan St, Melbourne, 3010, Australia
A review of a geomorphological framework for land type polygon (Land Systems)information is being carried out in the State of Victoria, Australia. There is a history of describing land in Victoria as a hierachical system which is scale dependent. The existing system prior to the review has used geomorphology as a framework for polygonal land units that incorporates a range of data such as soils, landforms and vegetation at finer scales. The review which has been underway since the late 1990's still has the objective of a framework for existing and new soil and land mapping but needs to incorporate new data as well as capturing existing expertise while available. An expert panel was assembled consisting of academics, public service specialists and consultants; many retired or semi retired. A key premise was their ability to give the best possible overview of how the framework could be reviewed. This is predominantly an iterative process with many of the panel giving freely of their time, though other priorities have reduced the time given to this process. A scheme of three levels (or Tiers) has been agreed to which replaces the two levels in the existing scheme. There are seven Divisions at Tier 1 the broadest level (with an addition of coastal features). There are approximately 25 divisions at Tier 2 level and approximately 75 divisions at Tier 3. The Land System units are the building blocks that fit into this Framework, which themselves are divided into other units or components where soil data resides. A number of discussions continue on the homgeneity of similar groups such as Uplands and Lowlands. For example, so far there are contrasting criteria for Upland groupings where topographical and litholgical aspects vary in their importance to land behaviour description. A report template as well as mapping for the whole State is underway to various degrees with much of the progress available via Victorian Resources Online (VRO)- a Dept. of Primary Industries (DPI)website.