Green Revolution-1 (1)
Energy Subsidies in Food Production
Understanding Energy Subsidies
Energy input: 5 calories of energy from human and fossil fuels are required to produce food for every 1 calorie received from food.
The food experiences an energy subsidy of 5.
Uses of input mass as an alternative measure for energy:
Feedlot Beef:
20 kg (44 lbs) of grain → 10 kg (22 lbs) of beef, with an energy subsidy of 20.
Chicken Meat:
2.8 kg (6 lbs) of grain → 1 kg (2.2 lbs) of chicken meat, energy subsidy = 2.8.
Traditional Small-Scale Agriculture:
Requires fewer energy inputs per calorie produced.
Modern U.S. Diet:
Estimated at a 10-calorie energy input for every calorie consumed, primarily from fossil fuel energy.
Transportation Energy Use:
Average food item travels 2,000 km (1,240 miles) from farm to table.
17% of U.S. commercial energy use is for food production (Department of Energy).
The Green Revolution
Overview:
A shift in agricultural practices in the 20th century: management techniques, mechanization, fertilization, irrigation, improved crop varieties.
Initiated by scientists like Norman Borlaug, who developed disease-resistant wheat strains.
Impact:
Increased production dramatically; helped developing countries feed growing populations.
Transitioned from small farms to large industrial operations.
Land Requirements for Food Production
Feeding with Corn vs. Beef:
A hectare yields 370 bushels of corn.
Assumption: a person requires 2,000 kilocalories/day.
Food requirements calculation:
Total: 730,000 kilocalories/year.
Corn yield:
370 bushels/hectare → 37,000,000 kilocalories/hectare.
Land requirement = 0.02 ha (0.05 acres) for a year.
Feeding with Beef:
Producing 1 kg of beef requires 20 kg of grain.
Land requirement = 0.4 ha (1 acre) for beef.
Global Implications:
Earth has ~1.5 billion ha of land suitable for food.
2.72 billion ha required to feed 6.8 billion people on a beef-only diet.
Agricultural Practices
Mechanization:
Costs of equipment like combine harvesters can vary between $150,000-$400,000.
Larger farms benefit from economies of scale.
Single-crop farms are more efficient due to reduced equipment costs.
Irrigation:
Transforms unproductive land into high-yield agricultural areas.
Irrigated land (16% of agricultural land) produces 40% of the world’s food.
Negative Effects:
Groundwater depletion, waterlogging, and salinization.
Fertilizers:
Nutrients: nitrogen, phosphorus, potassium (NPK).
Types:
Organic: from animal manure and plant materials.
Synthetic: produced using fossil fuels; more concentrated and quickly absorbed.
Use increased from 20 million metric tons in 1960 to nearly 200 million in 2011.
Environmental Impacts
Monocropping:
Dominant agricultural practice; enhances productivity but increases vulnerability to pests and soil erosion.
Large expanses of one crop create favorable conditions for pests.
Pesticides:
Types of Pesticides:
Insecticides and Herbicides: Target specific pests and plants.
Broad-Spectrum vs. Selective: Some kill a wide variety of pests; others target specific species.
Pesticide Resistance:
Pest populations evolve resistance leading to the pesticide treadmill effect, requiring new pesticide development.
Pesticides can harm non-target organisms and pollute waterways, posing risks to farmers and ecosystems.