Agriculture, like other economic sectors in the developed world, has experienced significant structural change over recent decades as farm size, intensity, capitalisation and specialisation have dramatically moved from traditional to industrial configurations. From an historical perspective, the rate of change occurring in agriculture has varied from the imperceptible to the dramatic with many writers recognising three periods of great change or "agricultural revolutions" (Troughton 1986; Bowler 1 992). The developments of recent decades make up the latest of these revolutions. The first agricultural revolution, the prehistoric domestication of crops and animals and the development of the plough, resulted in farming replacing hunting and gathering as the basis of subsistence. With the second agricultural revolution, many centuries later, farming changed from subsistence to commercial modes of production in response to the growing urban markets arising out of the industrial revolution. This new commercial agriculture diffused rap idly to the areas of overseas colonisation including Canada where most agricultural settlement by Europeans was market-oriented from the start. The third period of dramatic change has occurred since about the Second World War and is referred to as "'agricultural industrialisation" or "agricultural restructuring" (Troughton 1982). Theory relating to agricultural restructuring suggests that changes in the spatialpatterns of agricultural activity have resulted from the restructuring process. While these spatial changes can be examined at many scales, the purpose of this research note is to analyse broad, Canada-wide, adjustments using provincial-level data for the post-war restructuring period from 1951 to 1991.
Tremendous diversity characterises Canada's geography contributing to on-going regional disparity problems. In most parts of the country, the first non-Native immigrants came in search of farmland. With very different technology and priorities compared to the present, they settled many land types including the southern Shield, the uplands throughout the Maritime provinces and the northern Clay Belts, areas that are now considered agriculturally unsuitable. These regions, which have all experienced precipitous declines in agricultural activity over the twentieth century, illustrate the increasing relative disadvantage of certain locations and environments associated with recent agricultural restructuring (Mandale 1984; Parson 1979, 1990; Troughton 1982-83, 1988).
Many theories of the agricultural restructuring process in developed countries have been proposed (Pierce 1994). These theories take large to small scale approaches and examine the contribution of political, economic or individual factors in reshaping the structure and role of agriculture in the context of broader economic change. An important theme in this work relates agricultural change to the productivity gains resulting from the substitution of capital for labour (Hayami and Ruttan 1985). In terrelated is the growing significance of agribusiness as agriculture has become an increasingly international pursuit (Commins 1990; Found 1996; LeHeron 1993). Although regional and local markets still exist in urban-centred locations (Bryant and Johnston 1992), the development of global food systems means that many small producers with limited resources are increasingly marginalised.
With restructuring, agriculture has become increasingly intensive, spatially concentrated and specialised (Bowler 1992). Intensification, the increased use of off-farm inputs including machinery, chemicals, hybrids and technology, has resulted in significantly higher per hectare output and in capital replacing labour. Farmers who cannot afford to adopt these new technologies or whose land is unsuited, enter a cyclical downward spiral and eventually go out of business (Beattie et al 1981). Concentration, a related outcome, translates into farm production increasingly focused on fewer, larger farms in the most productive regions. …