Von Thunen’s model

1. Von Thunen’s model AND THE GREEN REVOLUTION

2. The Assumptions (1826) • The central city is located centrally within an "Isolated State" which is self-sufficient and has no external influences. • The Isolated State is surrounded by an unoccupied wilderness. • The land of the State is completely flat and has no rivers or mountains to interrupt the terrain. • The soil quality and climate are consistent throughout the State. • Farmers in the Isolated State transport their own goods to market via oxcart, across land, directly to the central city. Transport costs thus rise linearly with distance. • The selling price for the agricultural products is determined at the market by supply and demand. • Farmers act to maximize profits.

3. The “Central City” • There are four rings of agricultural activity surrounding the city. • Dairying and intensive farming occur in the ring closest to the city. The related products (vegetables, fruit, milk and other dairy products) have the highest profits, but also the highest transportation costs because they are vulnerable and perishable. • Timber and firewood will be produced for fuel and building materials in the second zone. Before industrialization (and coal power), wood was a very important fuel for heating and cooking. Wood is very heavy and therefore difficult and costly to transport. • The third zone consists of extensive field crops such as grain for bread. Since grain lasts longer than dairy products and is much lighter than wood transport costs are considered to be lower, allowing a location further from the city. • Ranchingis located in the final ring surrounding the central city. Animals can be raised far from the city because they are self-transporting and thus have low transport costs. • Beyond the fourth ring lies the unoccupied wilderness (hinterland), which is too great a distance from the central city for any type of agricultural product.

4. Von Thunen’s Model

5. Where would you find… • Farmers harvesting wheat? • Cows grazing in a field? • Lumberjacks cutting down trees? • A farmer selling fruits and vegetables? • A dairy farm?

6. The Green Revolution • Practices • Modified genetics (originally cross breeding, now genetic manipulation) • Fertilizers • Pesticides • Irrigation • Fattening livestock • Capital investments

7. The Green Revolution • What is it? • Beginning in the 1930s, American farmers begin using technologically manipulated seeds • Example: • IR8 – dwarf Chinese rice is crossed with Indonesian rice • Results: bigger head of grain, stronger stem • IR36 – bred from 13 parent plants • Results: rice is resistant to 15 insects, growing cycle is only 110 days, 3 crops per year in warm climates

8. The Green Revolution • Around the World • America – 1930’s and 1940’s – corn (maize) • India – 1960’s – rice • Asia – 1970 to 1995 – 67% increase in rice production

9. The Green Revolution • Factors that encourage success • The revolution came on the scene as the world was waking up to the significant hunger crisis • Increased yield, shorter growing seasons increase food supply • Increased yield leads to greater market presence, trade

10. The Green Revolution • Factors that limit the success • Emphasis on rice, corn and wheat meant little impact in Africa, where it was most needed • Monocropping (the practice of emphasizing only one crop) leads to vulnerabilities due to weather/insect/nature challenges • Soil erosion due to overfarming • Water shortages due to irrigation demands • Concerns over health risks associated with fertilizers, pesticides and GMOs • Small family farms aren’t competitive in techno-seed agriculture