Figure 8.21 Von Thünen’s isolated-state model. The model is modified to fit the modern world better, showing the hypothetical distribution of types of commercial agriculture. Other causal factors are held constant to illustrate the effect of transportation costs and differing distances from the market. The more intensive forms of agriculture, such as market gardening, are located nearest the market, whereas the least intensive form (livestock ranching) is most remote. Compare this model to the real-world pattern of agricultural types in Uruguay, South America, shown in Figure 8.22. Why does the model have the configuration of concentric circles?