Environmental Systems and Societies (ESS) Revision Guide

Quick Overview of ESS Topics

  • 8 Broad Topics:
    1. Foundations of Environmental Systems and Societies
    2. Ecosystems and Ecology
    3. Biodiversity and Conservation
    4. Water and Aquatic Food Production Systems and Societies
    5. Soil Systems and Terrestrial Food Production Systems and Societies
    6. Atmospheric Systems and Societies
    7. Climate Change and Energy Production
    8. Human Systems and Resource Use

Papers and Assessment Structure

  • Paper 1:

    • Duration: 1 hour
    • Marks: 35
    • Weight: 25% of total grade
    • Includes case study, resource booklet questions, and a mini essay

  • Paper 2:

    • Duration: 2 hours
    • Marks: 65
    • Weight: 50% of total grade
    • Section A: Short answers based on graphs/diagrams
    • Section B: Essay questions (two sets from four options)

  • Internal Assessment:

    • Marks: 30
    • Weight: 25% of total grade
    • Requirement: Written report (1500-2250 words)

Foundations of ESS

1. Environmental Value Systems (EVS)
  • Definition:
    • An EVS is a worldview that influences how individuals or groups perceive environmental issues.
  • Key Influences:
    • Cultural, religious, economic, socio-political contexts
  • Spectrum of EVS:
    • Ecocentric (nature-centered)
    • Anthropocentric (human-centered)
    • Technocentric (technology-centered)
1.1 Historical Influences on EVS
  • Historical Events:
    • Moon landing, environmental disasters (e.g., Chernobyl, Fukushima)
  • Media Influence:
    • Save the Whale campaign, Silent Spring, An Inconvenient Truth
  • Environmental Movements:
    • Greenpeace, WWF, Friends of the Earth
1.2 EVS Spectrum

  • Ecocentric:

    • Values ecological balance, less materialistic living, prioritizes biodiversity rights, focuses on self-restraint
    • Example Case Study: Buddhist societies

  • Anthropocentric:

    • Advocates for human management of environmental issues, reliant on consensus and pragmatic approaches
    • Example Case Study: Judaeo-Christian ethics

  • Technocentric:

    • Believes technology can resolve all environmental issues, supports scientific research for sustainability
    • Subcategories: Environmental managers and Cornucopians

Systems and Models

1.3 Systems in Environmental Science
  • Definition of a System:
    • An assemblage of parts that work together; includes inputs, outputs, flows, and storages
  • Types of Systems:
    • Open: exchanges both energy and matter
    • Closed: only exchanges energy
    • Isolated: no exchanges
1.4 Energy and Equilibria
  • Laws of Thermodynamics:
    • First Law: Energy cannot be created or destroyed, only transformed.
    • Second Law: Energy disperses; disorder increases over time, explaining inefficiencies in energy transfer in ecosystems.
Feedback Mechanisms
  • Negative Feedback:
    • Stabilizes a system, returning it to its previous state
  • Positive Feedback:
    • Drives change away from equilibrium, leading to new equilibrium states

Sustainability

1.5 Concepts in Sustainability
  • Definition of Sustainability:
    • Management of resources allowing for the natural replacement and recovery of ecosystems
  • Terminology:
    • Natural Capital: resource that yields sustainable income
    • Renewable, replenishable, and non-renewable resources are defined.
Importance of Biodiversity and Conservation

  • Biodiversity:

    • Variability in species, genetics, and ecosystems; increasing habitat diversity enhances species diversity.

  • Conservation Indices:

    • Simpson's index to assess biodiversity health

Pollution and Human Impact

2.1 Human Pollution
  • Definition:
    • Addition of harmful substances by human activity surpassing the environment's ability to cope.
  • Types of Pollution:
    • Point-source (e.g., Chernobyl) vs. non-point source (e.g., urban runoff)
Pollution Management
  • Strategies:
    • Altering human activities, regulating emissions, and restoring ecosystems after damage.

Aquatic and Soil Systems

Water Systems
  • Water Cycle:
    • Interactions of water through various phases and human impacts on water availability.
Soil Systems
  • Soil Management:
    • Soil profiles, transfers, and transformations, focusing on agricultural practices and sustainability.

Climate Change and Energy

Climate Change Impacts
  • Greenhouse Effect:
    • Natural process enhanced by human activities leading to global warming and its environmental consequences.
Energy Resources
  • Types:
    • Renewable (solar, wind) vs. non-renewable (fossil fuels) resources, discussing advantages and disadvantages.

Human Population Dynamics

Population Growth

  • Factors Influencing Growth Rates:

    • Birth and Death rates, social structures, and resource availability.

  • Carrying Capacity Models:

    • Understanding limits on population supported by environmental resources.