Environmental Science Study Notes

Environmental Science (CE 155) Lecture Notes

UNIT 1

Objectives / Goals
  • At the end of the course, students should understand the composition and operational mechanisms of various elements in the environment.
  • Students should have knowledge of sources and management strategies for various types of environmental pollution.
Learning Outcomes
  • Appreciate the effects of domestic, industrial, vehicular, and other anthropogenic emissions and their causal impacts on the environment.
  • Identify, diagnose, and resolve issues associated with these activities.
Course Outline
  1. Environmental Ethics and Sustainable Development (SDGs & Resources)
    • Weeks 1 & 2
    • Activity: Lecture Tour/Field Survey
  2. Ecological Concepts and Interactions
    • Week 3
    • Activity: Lecture Group Work
  3. Global Crisis
    • Week 4
    • Activity: Lecture
  4. Soil Formation & Nutrient Cycles
    • Weeks 5 & 6
    • Activity: Lecture
  5. Environmental Impact Assessment (EIA), Public Health Hygiene & Public
    • Weeks 7 to 10
    • Activity: Lecture & Presentation
  6. Water Quality
    • Weeks 11 & 12
    • Activity: Lecture & Presentation

Environmental Science Overview

  • Environmental Science is an interdisciplinary field that includes both scientific and social aspects regarding human impact on the world.
  • Involves understanding scientific principles, economic influences, and political actions.
  • Quote by John Muir: “Tug on anything at all and you will find it connected to everything else in the universe.”
  • Example in local ecology: Development at the College of Engineering led to loss of reptile populations like pythons and an increase in rodent populations, attracting predators like owls and hawks. Water quality in local streams decreased due to deforestation and increased evaporation.

Environmental Ethics

  • Ethics: A branch of philosophy defining right and wrong, relevant to environmental issues.
  • Example of ethical actions includes helping a neighbor or not littering.
  • The goal is to focus on the moral foundation of environmental responsibility, including:
    1. Anthropocentrism: All environmental responsibility stems from human interest. Adage: ‘protect when it benefits humans.’
    2. Biocentrism: All forms of life have inherent rights to life.
    3. Ecocentrism: The entire environment has intrinsic moral worth, deserving consideration.
Sustainable Development
  • Definition: “Meeting the needs of current generations without compromising the ability of future generations to meet theirs.”
  • Focuses on balancing economic development, social equity, and environmental protection.
  • Cultural development is sometimes considered a fourth pillar.

Ecosystems

  • The UN Conference on Environment and Development (1992) outlined the roadmap for sustainable development and acknowledged international challenges.
Key Definitions
  • Resource: Any entity of limited availability or anything helping to earn a living.
    • Natural Resources: Derived from the environment.
    • Human Resources: Involves human input/efforts.
Types of Natural Resources
  1. By Origin: Biotic (living), e.g. forests, animals; Abiotic (non-living), e.g. minerals, water.
  2. By Stage of Development:
    • Potential Resources: Not currently in use but may be exploited in the future.
    • Actual Resources: Currently used, amount and quality known.
  3. By Renewability:
    • Renewable Resources: E.g. sunlight, wind, and plants, which can replenish naturally.
    • Non-renewable Resources: E.g. fossil fuels and metals, which deplete over time.
Mitigation Measures
  • Recycle: Returning materials back into use.
  • Reuse: Using items multiple times before disposal.
  • Reduce: Cutting down on consumption.
  • Recovery: Developing technologies to recover minerals from used ores.

The Environment

  • Defined as the totality of external conditions affecting the development and life of an organism; it encompasses physical, biological, cultural, and socio-economic factors.
    • Physico-chemical: Includes water, air, soil.
    • Biological: Refers to terrestrial and aquatic life.
    • Cultural: Influences like beliefs and practices.
    • Socio-economic: Population dynamics, economy, infrastructure.

Environmental Engineering

  • Application of science and material theories to solve ecological and socio-economic issues by reducing pollution and ensuring sustainable practices concerning air, water, and soil.

UNIT 2

Ecological Concepts
  • Ecology: Study of relationships between organisms and their environment.
  • Ecosystem: A self-sustaining and regulating community of organisms.
  • Biotic Factors: Living components of an ecosystem.
  • Abiotic Factors: Non-living components like air, water, soil.
Interaction Types
  1. Predation: One organism (predator) kills and eats another (prey).
  2. Competition: Organisms competing for limited resources, either intraspecific (same species) or interspecific (different species).
  3. Symbiosis: Close and long-lasting relationships between species, featuring types like:
    • Parasitism: One benefits at the expense of another.
    • Commensalism: One benefits while the other is unaffected.
    • Mutualism: Both organisms benefit from the interaction.
Trophic Levels
  • Producers (first level), primary consumers (herbivores), secondary consumers (carnivores), and decomposers occupy different trophic levels.
  • Energy transfer follows laws of thermodynamics, and with every level, energy is lost as heat.
Energy Flow in Ecosystems
  • Energy flow involves complex interactions and recycling of materials, necessary for ecosystem stability and function.
Food Chains and Food Webs
  • Food Chain: Linear sequence of organisms through which energy and nutrients pass.
  • Food Web: Interconnected food chains representing multiple feeding relationships.
Energy Laws
  1. First Law: Energy cannot be created nor destroyed, only transformed.
  2. Second Law: In every energy transformation, some energy is lost as entropy, typically as heat.
Climate Change and Environmental Crisis
  1. Global Warming: Elevated temperatures due to greenhouse gases, causing drastic environmental changes.
  2. Ozone Layer Depletion: Resulting from pollutants like CFCs, impacting health and ecosystems.
  3. Acid Rain: Formation of acids from industrial emissions affecting soil and water quality.
  4. Land Pollution: Detrimental impacts on ecosystems and public health from hazardous waste.

UNIT 3

Environmental Crisis Details
  • Identifies a variety of global issues including resource depletion, pollution, and climate change.
  • The Earth’s atmosphere comprises different layers, each with varied temperature dynamics affecting environmental conditions and climate systems.
Ozone Layer
  • Critical for filtering UV radiation, pollution from CFCs leads to its degradation, impacting ecosystems and human health, including increased risk of skin cancer.
Greenhouse Gas Effect
  • Natural occurrence crucial for maintaining temperature but exacerbated by human activities, leading to climate instability.
Pollution Types
  1. Water Pollution: Contaminants in water bodies harming ecosystems and human health.
  2. Air Pollution: Emissions from vehicles, industries, and natural occurrences like volcanic eruptions.
  3. Land Pollution: Accumulation of hazardous waste in soils.
Solutions
  • Implement environment-focused regulations, promote renewable energy, enhance recycling and reuse, and educate communities about sustainable practices.

UNIT 4

Soil Formation
  • Land is defined as non-ocean covered portions of Earth, while soil is the thin layer supporting plant life composed of minerals, organic matter, and living organisms.
  • Soil components include minerals (45%), organic matter (5%), air (25%), and water (25%).
Soil Profiles and Horizons
  • Layers of soil differ in composition and properties: A (topsoil), B (subsoil), and C (parent material).
Chemical and Physical Properties of Soil
  • Characteristics such as texture, structure, moisture, and nutrient content influence soil's fertility and usability for agriculture.

UNIT 5

Environmental Impact Assessment (EIA)
  • A systematic process evaluating potential environmental impacts prior to project implementation, ensuring that decision-makers consider environmental factors thoroughly.
  • Key stakeholders include project proponents, government agencies, environmental consultants, and local communities.
Legal Framework and History
  • EIA was incorporated into environmental policy in 1970 in the USA, establishing standards for evaluating ecological effects across development projects.