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Unit 6 – Economic Geography I: Agriculture
38:180 Human Geography
Agriculture within Economic Geography• Sectoral division of economy:
– Primary– Secondary– Tertiary– Quaternary– Quinary
• Indicator of economic development– Share of employment– Share of GDP
• … and as precondition for civilization
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Evolution of Agriculture
• Hunter – Gatherer– Improved by tools and fire
• First Agricultural Revolution (up to 14,000 years ago)– Plant domestication– Domestication of animals– More sedentary settlement pattern– Subsistence agriculture
• “Shifting cultivation”• “Slash and burn”
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Evolution of Agriculture
• Second Agricultural Revolution (17th and 18th centuries)– New crops (colonial exchange)– Larger fields (consolidation of land-holding)– Crop rotation, soil preparation, etc.– New technologies: seed drill, tractor, combine
(eventually)– Advances in breeding (e.g. dairy vs beef cattle)– Banking (lending)– Railway
Evolution of Agriculture
• Third Agricultural Revolution (from 1930s)– Principally driven by more modern, scientific
approach to engineering seed hybrids• Maize/corn in Mexico• Rice in India and Philippines• Wheat in North America
– Debate over environmental impacts; who benefits
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Locational Factors
• Physical– Climate– Soils– Topography
• Technological• Cultural (religion and ethnicity)• Institutional (state)• Economic
– Principally, competition for land
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Why is Agriculture Spatially Dispersed?Reasons are principally economic:• Productivity of land is not the same
everywhere (for the same type of produce).
• Agriculture competes with other land uses / users.
• Markets for agricultural products are geographically dispersed.
• Agriculture is inherently land extensive
Von Thünen and the Bid Rent Model
• Because agriculture is spatially dispersed, transportation costs are a significant factor in its location logic.
• Key element of competition is over proximity to the market.
• Resulting spatial regularities make this process amenable to modeling.
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• Why does proximity matter?– direct costs of transport– perishability– risk of damage
• Technology can alter the friction of distance.
• ‘Good’ agricultural land is good for many different uses.
Von Thünen and the Bid Rent Model
• Johann Heinrich von Thünen, The Isolated State.– The first model of spatial organization based
on economic principles.• Von Thünen was a land owner, with
different agricultural activities at different places on his estate.
• He wondered what would be the optimal arrangement of land use on his estate.
Von Thünen and the Bid Rent Model
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Rent:• Economic Rent: ER = p - c
where:– ‘p’ = price– ‘c’ = cost
Von Thünen and the Bid Rent Model
Assumptions of von Thünen’s model:1) Homogenous physical plane2) Uniform transportation surface3) Single market centre served 100% by its
agricultural hinterland4) Farmers are profit maximizersThe model von Thünen develops describes
the spatial structure of location rents.
Von Thünen and the Bid Rent Model
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Location Rent: economic rent specifically derived from location (e.g. due to proximity to the market).
LR = Q(p – c) – QfkQ = quantity produced per unit of landp = price per unit of outputc = cost per unit of outputf = freight rate per unit of outputk = distance to market
Von Thünen and the Bid Rent Model
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The Real World and Modifications
What happens when we relax the assumptions?
• Introduce a transportation corridor• Introduce another (competing) market
centre
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The Real World and Modifications
To what extent is the model reflected in reality?
• developing countries• market gardens (local scale)• the national pattern in Canada, US (macro
scale)• predictive capacity of ‘distance’, likely to
be reinforced by rising fuel costs
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The Real World and Modifications
How was the ‘Crow Rate’ related to von Thünen’s principles?
• reduced transport costs to producers• distorted the pattern of agricultural
production in Canada’s Prairies
Bid Rent Functions with (LR1) and without (LR2) Crow Rate for Prairies (P) and Quebec (Q)
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The Real World and Modifications
Effects of the Crow Rate:• stalled industrialization in the Prairies• maintained an otherwise uneconomic
grain production pattern• deterioration of railways
The Real World and Modifications
Effects of Removing the Crow Rate:• diversification of agriculture in the Prairies• increased off-farm employment, dual
income farm families• changing profile of farm-related industry• sale of farms (and shift from ‘family
business’ to agribusiness / corporate farms)
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General Forms of Diversification
A response to several factors driving agricultural restructuring, especially in commercial agriculture systems (most notably the ‘cost-price squeeze’)
1) Shift to other crops2) Shift to other agricultural products3) Alternative methods (e.g. organic)4) Off-farm employment5) Shift to related industry (e.g. farm tourism)
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Agriculture and Cultural Landscapes
• Basic relation between humans and environment• Production system as culture
– extensive vs intensive• Land survey systems• Building materials / styles
– Barns, fences, etc.• Technology (e.g. irrigation)• Food as element of culture• …and the ‘character’ of a place
Subsistence Agriculture