Geomorphology and soils have been used in conjunction to with recognition of farming system differences to delineate six regional 'primary production landscapes' (PPL) comprising twenty two sub-regions in Victoria. This spatial hierarchy provides a regional platform from which to explore climate change and climate variability impacts on agricultural industries, management practices and soils.
The Victorian landscape exhibits a rich variety of terrestrial ecosystems that is a result of diverse terrain (from the mountains to the plains), climate (alpine to semi-arid), geology and soils. Agriculture has adapted to this diversity, giving rise to differences in land use and management practices around the state in response to rainfall, seasonal temperature conditions, availability of irrigation water, and soil quality.
Over the last fifty years, land use practices have become relatively finely-tuned to climate and soil. Although climate over that period has been highly variable with respect to droughts, good years and wet years, models of the future climate are showing a general shift to drier and hotter conditions.
There are many important questions for the future of Victorian agriculture and its adaptation to changing climatic conditions. For example:
o How might this predicted climate change affect the current distribution of land use?
o Will practices within a particular land use have to change?
o Will some land uses become less competitive or unprofitable?
o How will soils and soil management be affected?
Because farming systems, practices and productivity are different in different parts of the state, answers to these questions will differ according to the land use and where it is placed in Victoria. A regional approach to analysis of these different situations is needed. This will assist in providing regionally relevant scenarios and advice. A division of Victoria into major 'Primary Production Landscapes' is proposed.
The approach is similar to that applied in defining 'Agro-ecological zones' (AEZ), in which climate and soil properties are used to map and determine the suitability of land for different crops (FAO 1981). However, in a time of uncertainty regarding future climate, it is not possible to use climatic data to define fixed attributes of a zone. On the other hand, terrain and location (e.g. relative to the coast or high country) have a local influence on climate (e.g. continental rainfall gradients, orographic rainfall, and temperature gradients) and are relatively permanent features. Landscape differences (soil and terrain) in combination with general spatial trends in climate can therefore be used to delineate 'agro-ecological landscapes' (AEL), or areas with different potential for land use and different requirements for management (e.g. waterlogging may be a constraint that requires special consideration in some landscapes). Primary Production Landscapes are AELs augmented with descriptions of primary production land use and management practices.
The project has developed an approach that encapsulates information on landforms, soils, farming systems, management practices and future climate predictions. Understanding the agricultural capability for production as well as potential impacts on the displacement and redundancy of infrastructure for land uses remains a challenge for NRM managers, planners and policy makers. This spatial hierarchy of PPLs provides a regional platform from which to explore climate change and variability impacts upon agricultural industries and to target investment.

Reference
FAO (1981) Report on the agro-ecological zones project (1978-1981), Volume 1: methodology and results for Africa. World Soil Resources Report 48/1. Food and Agricultural Organisation (FAO) of the United Nations, Luxemburg, Austria, Rome, Italy.