Environmental Science and Sustainability Notes
Environmental Science and Sustainability Notes
American Desert Historical Perspectives
- Great Plains: Once considered the "American Desert", unsuitable for European farming.
- Steel Plow (1837): Invention by John Deere that revolutionized farming by making it easier to till the tough soil.
Rain Follows the Plow (1860s-1880s)
- Myth: Belief that farming led to increased rainfall due to a period of wet weather.
- Implications: Prairie grasslands replaced by domesticated crops, leading to temporary agricultural success.
Dust Bowl (1930s)
- Causes: Stock market crash led to overplanting, followed by severe drought.
- Consequences: Loss of 1/3 of topsoil, mass migration, and significant farming crisis.
Green Revolution: Major Changes in Agriculture
- Rise of monocultures and genetically modified crops.
- Increased use of irrigation and chemical inputs (fertilizers, pesticides).
- Multiple crop rotations adopted on the same plots.
- Intensified energy use in agriculture.
Types of Agriculture
- Industrialized Agriculture: High-yield monocultures supported by heavy inputs (financial, labor, machinery).
- Traditional Agriculture: Low-input systems focused on subsistence or limited commercial production.
Types of Crops
- Cash Crops: Grown for sale (e.g., corn, soybeans).
- Subsistence Crops: Grown for the farmer's family consumption (e.g., rice, wheat).
Total Factor Productivity (TFP)
- Definition: Increase in agricultural output without proportional increase in inputs.
- Soil Formation: Takes 100-1000 years to create 1 cm of fertile soil.
- Soil Degradation: Threatens food security and arises from factors like erosion, overgrazing, and industrialization.
Desertification and Salinization
- Desertification: Permanent loss of productivity; results from overuse leading to water retention issues.
- Salinization: Occurs through over-irrigation, leading to salt buildup that hampers vegetation.
Soil Erosion Types
- Splash Erosion: Initial stage, small soil particles displaced by raindrops.
- Sheet Erosion: Thin layers of soil washed away by water flow.
- Rill and Gully Erosion: More severe forms, leading to visible channels.
Agricultural Pollution
- Eutrophication: Excessive nutrient runoff leading to algal blooms and fish kills.
- Riparian Zones: Require protection to manage sediment and nutrient flow to waterways.
Biodiversity in Agriculture
- Importance of Seeds: High-quality seeds are crucial for good yields.
- Genetically Modified Organisms (GMOs): Crossbreeding and artificial selection methods have greatly increased the prevalence of GMOs in agriculture.
Soils and Nutrients
- Essential Nutrients: Nitrogen, phosphorus, and potassium are vital for plant growth; their depletion requires replenishment through fertilizers.
- Nitrogen and Phosphorus Cycles: Critical for sustaining agricultural productivity but subject to human impacts.
Pest Control Methods
- Ecological/Biological Controls: Use of natural predators and parasites to manage pest populations.
- Chemical Controls: Usage of synthetic pesticides, their benefits, and disadvantages like pest resistance.
Integrated Pest Management (IPM)
- Combines biological control and minimal chemical usage while maintaining ecological balance.
Organic Farming Standards
- No synthetic chemicals or GMOs; must align with animal welfare standards and undergo certification.
Kentucky Agricultural Overview
- Majority family-operated farms; diverse crop production, strong emphasis on local resources and agricultural contributions.
Natural Capital Degradation
- Consequences of agriculture on biodiversity, soil and water quality, including impacts like pollution, deforestation, and water waste.
