APES UNIT 5

5.1 Tragedy of the Commons

• Definition: The phenomenon of using up a public resource to depletion. Examples include:

  • Overfishing

  • Overgrazing

  • Air and water pollution

  • Overusing groundwater

• Clear Cutting: The practice of cutting down all trees in a given area at once for lumber or land clearance.

  • Direct Effects: Leads to monoculture plantations where the same tree species is repeatedly planted, grown, and harvested.

  • Reason for Practice: Lack of regulations (e.g., Peru dumping hazardous waste into rivers without penalties).

  • Behavior: Individuals exploit resources to avoid losing them to others.

• Problems:

  • Overfishing causes fisheries to collapse, leading to loss of income and potential starvation for communities relying on fish.

  • Loss of biodiversity in fish populations affects ecological balance.

  • Air pollution from coal power plants leads to increased healthcare costs due to respiratory issues (asthma, bronchitis).

  • Pesticide runoff contaminates groundwater, posing health risks (drinking/bathing).

• Externalities: Negative side effects of human actions, e.g., farmers spraying pesticides pollute water without facing consequences.

• Solutions to Tragedy of the Commons:

  • Implement private ownership of resources.

  • Establish a permit system for grazing and logging.

  • Introduce taxes and fines for pollution and contamination.

  • Legislation such as the Clean Water Act, Clean Air Act, and Safe Drinking Water Act that impose fees.

  • Bureau of Land Management (BLM) collects grazing fees to manage public lands.

• Soil Erosion:

  • Caused by destabilized root structures, leading to sedimentation in streams and increased water temperature.

  • Loss of tree shade increases soil and stream temperatures.

• Flooding and Landslides:

  • Logging practices compact soil, reducing water retention and leading to flooding and potential landslides.

• Impact on Biodiversity:

  • Deforestation shifts biodiverse forests to single-species plantations, decreasing habitat and species diversity.

5.2 Forest Benefits and Deforestation Consequences

• The Green Revolution:

  • Shift from family farms to industrialized agriculture, with an emphasis on mechanization, high-yield crops, GMOs, synthetic fertilizers, and irrigation.

  • Consequences of Deforestation:

    • Loss of air pollution filtration, CO2 storage, and habitat for various organisms.

    • Slash and burn agriculture releases significant CO2 and other gases into the atmosphere.

• Benefits of Agricultural Practices:

  • Increased efficiency and crop yields lead to short-term profitability and food security.

  • However, practices like monocropping result in soil erosion and contamination of water supplies from runoff.

• Mechanization and Chemical Use:

  • Increased use of tractors and fertilizers leads to higher yields.

  • GMOs facilitate higher productivity but may decrease genetic diversity among crops.

  • Synthetic fertilizers can contaminate water bodies leading to algal blooms.

• Irrigation:

  • Essential for agriculture, especially in arid areas, but can deplete groundwater and surface resources.

5.3 Pesticides and Agricultural Practices

• Tilling:

  • Process of mixing and loosening soil can lead to soil erosion and loss of organic matter.

• Irrigation Methods:

  • Various methods including furrow, drip, flood, and spray, each with their pros and cons.

    • Drip irrigation is the most efficient but costly.

• Pest Control:

  • Overuse of pesticides leads to resistance in pest populations and unintended negative impacts on non-target species.

5.4 Meat Production Methods

• CAFOs (Concentrated Animal Feeding Operations):

  • Pros include efficient meat production.

  • Cons encompass animal waste contaminating water supplies and methane emissions contributing to climate change.

• Free-range Grazing:

  • Less efficient than CAFOs but better for animal welfare.

  • Risks associated with overgrazing include topsoil erosion and desertification.

• Fishing Practices:

  • Bottom trawling leads to bycatch and damage to marine ecosystems.

  • Overfishing downsizes fish populations, affecting the food web.

5.5 Mining Basics and Environmental Impacts

• Mining Techniques:

  • Surface mining, subsurface mining, and particularly harmful practices like mountaintop removal.

  • Tailings and slag can pollute streams and diminish biodiversity.

• Mine Reclamation:

  • Restoring land post-mining is necessary to mitigate environmental impact.

5.6 Urbanization and Ecological Footprint

• Urbanization Trends:

  • Movement from rural to urban areas increases population density but can reduce per-capita environmental impact.

• Ecological Footprint:

  • Measures the biophysical resources needed to support human activities.

  • Key factors include food production and energy consumption.

5.7 Sustainable Practices for Agriculture and Forestry

• Reducing Urban Runoff:

  • Solutions like permeable pavements and rain gardens.

• Integrated Pest Management (IPM):

  • A holistic approach to pest control that minimizes environmental impact.

• Soil Conservation Techniques:

  • Crop rotation, agroforestry, cover cropping, and no-till farming practices enhance soil health and reduce erosion risks.

5.8 Sustainable Aquaculture and Forestry

• Aquaculture Benefits:

  • Provides a sustainable source of fish while reducing pressure on wild stocks.

• Ecologically Sustainable Forestry:

  • Focuses on selective logging and replanting practices to maintain forest biodiversity and health.

• Recycling Wood and Reforestation:

  • Helps reduce deforestation and restores habitats.