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A model for analysing agricultural location patterns based on the pioneering work of a Prussian landowner, Johann Heinrich von Thünen (1966: originally published in 1826). His goal was to explain variations in farm product prices and the way they influenced the use of agricultural land. He envisaged a single market for the products and, by simplifying his analysis to a small number of variables only, suggested that distance from that market would be a prime determinant of the geography of agricultural land use. His model was a statement of what the contemporary distribution of land uses should be, given certain assumptions, and it has been widely used as a norm against which actual patterns are compared — thereby accepting that the assumptions are largely valid (Chisholm, 1979).
The model is constructed around the concept of rent and assumes that all farmers will produce that commodity which yields the \'highest\' rent in order to maximize their net returns. Their net profit is land rent (L), whose value is determined by the production costs per unit of the commodity (a), its market price (p), the yield per unit of land (E), and the distance from the market to the production point (k). These are combined to give (Dunn, 1954): L = E(p — a) — Efk
Land rent in this context differs from economic rent because it takes no account of opportunity costs and ignores what might be earned from alternative uses.
In the model\'s simplest applications only transport costs vary (i.e. prices, production costs and yields are held constant for each commodity): rates per unit of distance are highest for bulky and/or perishable items such as dairy products and timber. Thus land rent declines away from the market point where the net returns are greatest (cf. distance decay), but the rate of decline differs by commodity. The result is a family of land rent slopes, as shown for three commodities in the figure. If the distance-decay curves are translated from one- to two-dimensional space, they describe a zonal pattern of land use organization around the market point.
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von Thünen model Land rent variations and land-use patterns
Although geographers have focused on the distance variable in von Thünen\'s model, each of the others can be allowed to vary, generating idealized land-use patterns which reflect differences in land productivity, for example. Similarly, price changes and/or changes in production costs can be introduced, to illustrate how the zonal pattern might change as a consequence — on the assumption that farmers respond rationally to those changes (cf. rational choice theory).
Geographers were particularly attracted to the zonal component of von Thünen\'s model, having \'discovered\' it when locational analysis was a dominant paradigm, and its validity has been evaluated at a range of spatial scales from the global (Peet, 1969) to the individual village and farm holding (Blaikie, 1971; Chisholm, 1979): it also stimulated similar modelling of zonal patterns of intra-urban land use (cf. Alonso model). This concentration on spatial factors meant less recognition of the role of environmental factors as determinants of land-use patterns: only part of von Thünen\'s analytical framework was widely adopted by geographers, whereas the remainder was considered the source of a \'deviation\' from the basic principles of locational analysis.
As with most economic models, von Thünen\'s simplifies the \'real world\' in order to understand it. The processes of decision-making by farmers are considerably oversimplified, for example, and the elements of risk and uncertainty are ignored (see game theory and Wolpert, 1964). Its spatial component is thus no more than an ideal type, therefore, whereas its analytical framework has much wider applicability. (RJJ)
References Blaikie, P.M. 1971: Spatial organization of agriculture in some north Indian villages. Transactions, Institute of British Geographers 52: 1-40, 53, 15-30. Chisholm, M. 1979: Rural settlement and location, 3rd edn. London: Hutchinson; Atlantic Highlands, NJ: Humanities Press. Dunn, E.S. 1954: The location of agricultural production. Gainesville: University of Florida Press. Peet, J.R. 1969: The spatial expansion of commercial agriculture in the nineteenth century: a von Thünen explanation. Economic Geography 45: 283-301. Thünen, J.H. von 1966: Isolated state, an English translation of der isolierte staat, trans. C.M. Wartenberg, ed. P. Hall. Oxford and New York: Pergamon Press. Wolpert, J. 1964: The decision process in spatial context. Annals of the Association of American Geographers 54: 337-5 8.
Suggested Reading Grotewöld, A.A. 1959: Von Thünen in retrospect. Economic Geography 35: 346-55. |
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