8.1-8.3 APES notes- Aquatic and Terrestrial Pollution - Unit 8

Topic 8.1: Sources of Pollutants

Differences in Pollution Sources

• Point Source Pollution:

  • Definition: A point source refers to a single, identifiable source of pollution (e.g., smokestack, waste discharge pipe).

• Nonpoint Source Pollution:

  • Definition: Nonpoint sources are diffused, making them hard to identify (e.g., pesticide spraying, urban runoff).

Examples of Point Sources

• Concentrated Animal Feeding Operations (CAFOs): Discharge pipes release ammonia (nitrogen source) from animal waste and fecal coliform.

• Coal Power Plant: Emits CO2, NOx, SOx, and particulate matter (PM).

• Leaking Underground Gas Storage Tanks:

• Wastewater Treatment Facilities:

• Electronic & Automobile Manufacturers:

• Oil Refineries:

• Oil Spills: Notable incidents include the BP spill in 2010 (Gulf of Mexico) and the Exxon Valdez spill in 1989 (Alaska).

Clean Water Act

• Requirement: Industries classified as point sources must obtain a permit from the state or EPA prior to discharging effluent into any body of water.

• Mandate on Treatment: Effective technology must be employed to treat effluent before discharge.

Nonpoint Sources of Pollution

Types of Nonpoint Sources:

• Agriculture: Includes pesticides, fertilizers, herbicides, insecticides, and animal waste.

• Sediment: Arises from improperly managed construction sites or agricultural fields as well as eroding stream beds.

• Urban Runoff:

  • Consists of motor oil, road salt, sediments, leaking chemicals from vehicles, and grease.

  • Pesticides can be carried by wind or rain into other areas.

Challenges in Identifying Nonpoint Sources

• Difficulty in pinpointing specific sources in urban areas due to the nature of runoff and the variety of pollutants.

Hydrological Impacts

• Pre-Development vs. Post-Development:

  • Increase:

  • Impervious surfaces → Increase in drainage slope and direct runoff.

  • Decrease:

  • Evapotranspiration and groundwater recharge.

Managing Nonpoint Sources

• Collaborative Efforts: Private landowners, businesses, and state/local governments must work together to manage and maintain clean areas.

Effects of Sediment Pollution

• Low Dissolved Oxygen Levels:

  • Can suffocate fish (29259 fish reportedly affected).

  • Alters food webs and decreases fish populations.

• Impact of Sediment:

  • Stable soil prevents runoff into water, whereas unstable soil contributes to sediment pollution.

  • Clear, cooler water supports spawning, while sediment covers spawning areas and inhabits insect habitats.

Specific Pollutants and Their Ecosystem Impacts

• Studying Specific Pollutants: Aim for clarity and precision in detailing sources and impacts on ecosystems.

Study Recommendations

• Action Items:

  • Watch AP Classroom Videos.

  • Read specified pages in the Withgott Book.

  • Competencies to develop:

  1. Define and identify point source and nonpoint source pollution.

  2. State how the EPA regulates point source pollution.

  3. Identify management strategies for nonpoint source pollution.

Topic 8.2: Human Impacts on Ecosystems

Marine Challenges

• Statistics:

  • 30% of mangroves and seagrasses lost.

  • 90% decline in large predatory fish stocks due to overfishing.

  • Ocean acidification linked to carbon emissions.

  • An estimated 100 million sharks targeted by humans annually.

  • Rising sea levels resulting from a 0.7°C increase in global temperatures.

  • Approximately 300,000 whales and dolphins killed annually as bycatch.

  • 8-12 million tonnes of plastic enter the ocean each year.

  • 19% of coral reefs lost and 75% of global reefs threatened.

  • Mass coral bleaching events, notably 93% of the Great Barrier Reef have experienced bleaching due to increased ocean temperatures.

Topic 8.3: Endocrine Disruptors & Industrial Water Pollutants

Understanding Endocrine Disruptors

• Definition: Chemical compounds that interfere with endocrine systems in animals, binding to cellular receptors meant for hormones, thereby blocking hormone activity.

• Examples of Sources: Birth control and other medications can enter waterways through sewage or improper disposal.

Impact on Ecosystems

• Endocrine disruptors can significantly disrupt animal endocrine systems and overall ecosystem health.

Examples of Endocrine Disruptors

Heavy Metals as Endocrine Disruptors

Coal Ash and Heavy Metal Contamination

• Pathways: Arsenic, lead, and mercury can attach to fly ash carried by wind, affecting regions far from the source.

• Environmental Concerns: Bottom ash may leach or overflow, contaminating water sources or agriculture.