Agriculture

1. Agriculture

2. Agriculture: Deliberate land modification through plant cultivation and raising animals for food or profit. • Percentage of labor force MDC: 5% (avg.), LDC: 55%

3. Subsistence Agriculture: Food production primary for farm family consumption Example: slash and burn

4. Commercial Agriculture: • Food production primarily for sale off the farm • Can Start as subsistence farming, excess sold • Can transition to pure commercial agriculture

5. Wet Rice Agriculture • Generally expands to hillsides as population increases • In earthquake zones, mudslide risks increase… Also, storms.

6. Swidden Agriculture / slash and burn / shifting cultivation • Slash vegetation. • Burn the slashed veg. • Plant in nutrient ashes. • Yields drop off. • Change sites. Repeat. • Requires much land recovering from past slash and burn activities.

7. Shifting cultivation (observations) • SOUND: Done wisely, it is ecologically sound in otherwise uncultivable soils. • POPULATION: Increasing population density eventually makes this practice unsustainable. • TITLE: In some countries, land tenure (ownership) is established by cutting the land, not leaving it “idle” (letting it recover). • COMPETITION: In some places, shifting cultivation is being replaced by a pattern of logging, cattle ranching, and more intensive cash crop cultivation. • LOSS: This can be a first step in forest conversion to grassland.

8. Issues for subsistence agriculture: • Population growth • Forest fallow  bush fallow  short fallow  annual  multi-cropping • Intensification may not be sustainable. (Site dependent) • New farming methods require cash. • more inputs: fertilizer, manure, new tools, more labor intensive • new seeds and new crops • Needs to have enough income to fertilize, buy equipment, buy seed. • International trade pressure: • conversion of food crops to cash crops for more profit… • drug crops (can be involuntary) Examples: wet rice cultivation, dry farming • maximize yield per acre, minimize unused land, some double cropping • low machinery inputs, high animal and human inputs • dry farming  crop rotation

9. Pastoral nomadism works on marginal lands If you avoid overgrazing! Story:http://www.geographie.uni-freiburg.de/ipg/forschung/ap1/current_projects/chad/nomads_project%20area.html

10. MDC farming: • Mixed crop and livestock farming: crops  animals  humans (e.g. beef, milk, eggs) • crop rotation, nitrogen fixing crop intermixed with primary crop(s) • Dairy farming: within range of market (avoid spoiling), refrigeration extends this range • Grain farming: e.g. wheat belt • Livestock ranching: often on marginal lands in the West, also Amazonia, Pampas, Outback • Mediterranean agriculture: Horticulture: growing of fruits and vegetables, and flowers • Commercial gardening and fruit gardening: horticulture, large scale, migrant workers • Plantation farming: specialize in 1-2 crops, once slavery, now import workers

11. How Do you figure out what to grow where? Important Influences: • Market Price • Distance • Government policies • Large areas of levelled lands • Water supply • Transportation Cost • Perishability, (actually covered under transportation cost)

12. Von Thunen Model • Distance is a function of land rent and transportation costs. • Basically, what produces the most profit at each location? • http://people.hofstra.edu/geotrans/eng/ch6en/conc6en/img/vonthunen.gif • Info: http://people.hofstra.edu/geotrans/eng/ch6en/conc6en/vonthunen.html

13. Issues for commercial farmers: • Access to market: Von Thunen model (ring and transport) • Land rent and distance driven… too far  no profit, lose $ • Overproduction • encourage growth of crops with global demand • price subsidies • buy surplus yield, often donate to foreign governments • Unsustainable agriculture • move to more sustainable practices • sensitive land management • Ridge contour tillage • limited use of chemicals • (organic farming)

14. Issues for subsistence farmers: • Population growth • Forest fallow  bush fallow  short fallow  annual cropping  multi-cropping • Conversion from slash and burn to multi-crop farming may not be sustainable • Profit motives impact farmers. • Lure of money • Land loss (legal, and illegal) to for-profit activity

15. International trade pressure: • conversion of food crops to cash crops • may make the economy dependent on foreign foods • if so, cash crop shortfalls or price drops  avoidable food shortages • drug crops • forced or voluntary growth of drug crops

16. Strategies for increasing food supply: Increase agricultural land • marginal lands • require careful management for long-term yields • must worry about soil salinization, selenium, etc. • desertification: human action causes land deterioration to a desert-like state. • Increaseland productivity • greenrevolution • often requires nutrient inputs (external, cost) • often relies on machines (external, cost, needs gas) • seed stocks are foreign owned, possibly not self propagating

17. Strategies for increasing food supply: (part 2) Identify new sources: • Cultivate the oceans • We are already over-fishing now. • (Stock recovery, or risk extinction.) • Develop higher protein cereals (decrease meat demand) • Promote the consumption of under-used foods, e.g. soybeans (soy burgers, etc.) • increase trade • Reduces local famines • Works until you run out globally. • Who starves first?

18. Food supply crises Example: Africa • Population increases faster than local food supply. • Over-planting removes soil nutrients. • Trees harvested for firewood. • Overgrazing removes grasses and herbs. • Desertification is a major problem. • The desert has been marching south towards the sea. • Warfare, ethnic cleansing, cash crops, and global warming exacerbate the problem.

19. THANK YOU!!