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FR Discuss negative impact of agriculture on the environment. In the past century, agriculture has been characterized by enhanced productivity, the replacement of human labor by synthetic fertilizers and pesticides, selective breeding, and mechanization.
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FR Discuss negative impact of agriculture on the environment.
In the past century, agriculture has been characterized by enhanced productivity, the replacement of human labor by synthetic fertilizers and pesticides, selective breeding, and mechanization. The recent history of agriculture has been closely tied with a range of political issues including water pollution, biofuels, genetically modified organisms, tariffs, and farm subsidies. In recent years, there has been a backlash against the external environmental effects of mechanized agriculture, and increasing support for the organic movement and sustainable agriculture.
The Impact of Agriculture on the Environment • soil erosion
soil and water pollution (herbicides, pesticides, and fertilizers)
Sustainable agriculture integrates three main goals: environmental stewardship, farm profitability, and prosperous farming communities. Practices that can cause long-term damage to soil include excessive tillage (leading to erosion) and irrigation without adequate drainage (leading to salinization).
FR Von Thunen’s Agricultural ModelA land use model In into too
used to explain the importance of proximity to the market in the choice of crops on commercial farms
(this created a concentric pattern: circles sharing the same centers)
Von Thunen believed farmers compare two costs in deciding what to grow: transportation costs versus rent He defined rent as the difference between revenues received and costs paid — in other words, the profit earned from the land.
Because farmers must pay to transport their produce to the market, and these costs are directly proportional to distance, the profit for each product declines as a straight line with increasing distance from the market
The decline in profit with increasing distance from the market is an example of distance decay.
Von Thunen's model made several simplifying assumptions. • all the farmers in a certain area would send their produce to one market town • an evenly flat plain surrounded the market town • the fertility of the soil and the climate were the same everywhere on that plain • the cost of transport was the same in every direction from the market town, and directly proportional to distance.
Ring one • Intensive farming (fruits, vegetables, and dairying closest to the city
What is intensive agriculture?high inputs (labor, fertilizer, pesticides, machinery) makes a high cost so only a higher priced goods can turn a profit (strawberries for example)
Why is intensive farming used in the inner ring? • Perishable products (needs to get to the market quickly) • Higher land value so a higher value commodity must be produced • High transportation costs could prevent a profit
2nd Ring timber and firewood • Fuel and building materials for industrialization • Wood is heavy and expensive to transport if farther away from the market
3rd Ring Extensive field crops • Grains • Less profit per acre • However: • Cheaper to transport • Can locate further from the city (less perishable) on less expensive land
4th ring Ranching • Animal raising • Can be self transported
For example: On California’s poultry farms site factors are not as important as on other farms because chickens can be raised indoors on cheap land with poor soils.
The most ideal bioclimatic zone for wheat would be the Ohio River Valley and the great prairies of Iowa, Illinois, and Indiana, however, wheat is grown on the high plains farther west in the arid region. Wheat is grown there not because it is the best place to grow it, but because it is the crop that will yield a profit there while other crops will not.
Up to 10 miles farmers grow strawberries • 10-30 forest • 30-50 wheat • 50-80 cattle City 10 30 50 80 Now draw this on a map
Up to 10 miles farmers grow strawberries 10-30 forest 30-50 wheat 50-80 cattle Now draw this on a map City stawberries 10 forest 30 wheat 50 cattle 80
10 30 50 80 Distance from the market
$ tom 10 wheat 50 100 10 50 100 75
Discuss two factors that explain why agriculture land-use patterns today differ from those developed by Von Thunen’s model of 1826.What is this question asking?
Can grow crops further is zero points. The rings are bigger is still von Thunen
Examples of how the rings are not relevant today:Forest no longer is near the city
Refrigeration, preservation, canning and much faster transportation allows perishable products to be shipped from beyond the inner ring