So surprised tonight, my task still not be completed. Thus, I'll sleep very late.... Some of my resume on Von Thunen's theory,
The most famous model of all is that first proposed by Von Thunen in 1826. Von Thunen owned an estate near Rostock in Northern Germany and his major work, The Isolated state, was largely based on personal observations and deductions. The processes making for land use patterns in that area, Von Thunen argued, mighty equally apply elsewhere and with similiar results. In other words, the model can be expended into a general theory of land use patterns. The model in question is illustrated by the example of a single town in the midst of a uniform land surface where physical factors such a climate, relief, geology, soils and drainage remain constant and transport costs are directly proportional to distance. Each farmer would sell his surplus produce only in that town, would bear the total cost of transport himself, and would always aim to undertake that type of farming which yields maximum profits.
A cornerstone of the theory is the principle of economic rent, whereby different types of land use produce different net returns per unit area. Of the three commodities, potatoes yield the largest bulk per hectare and require the highest transport costs.
One aspect of agricultural land use that seems not to have concerned Von Thunen is the way in which it can be determined, and can change, in response to urban growth. This fact has led many geographers fundamentally to modify Von Thunen’s original hypothesis and to suggest alternative land use patterns. One such geographers is R. Sinclair.
Sinclair has developed a model in which agricultural land use pattern are to a certain extent at least, the reverst of those of Von Thunen. Instead of agriculture becoming less productive and less efficient away from a town, it actually becomes more productive and efficient. The reason for this, according to Sinclair is the blight effect that urban sprawl has on land values.
to be continue....on processing :3