Introduction to Environmental Science

Introduction

• The environment encompasses all surroundings and conditions supporting living organisms, including landscapes, animals, and their interactions.
• It consists of abiotic components (lithosphere, hydrosphere, atmosphere) and biotic components (plants, animals, microorganisms).

Environmental Science

• Environmental science studies the interaction of humans with the natural environment.
• It examines how humans utilize natural resources, relate to the nonliving environment, and alter the environment.
• Key areas of study include:
  • Interactions between living organisms and their nonliving surroundings
  • Impact of human activities on the environment
  • Interrelationships between various organisms

The Goals of Environmental Science

• To understand and solve environmental problems by examining:
  • How humans use natural resources
  • How human actions alter the environment

Fields of Study

• Environmental science is interdisciplinary, incorporating concepts from various fields:
  • Biology: Study of living organisms
  • Zoology: Study of animals
  • Botany: Study of plants
  • Microbiology: Study of microorganisms
  • Ecology: Study of interactions between living organisms and their environment
  • Earth Science: Study of Earth's nonliving systems and the planet as a whole
    • Geology: Study of Earth's surface, interior processes, and history
    • Paleontology: Study of fossils and ancient life
    • Climatology: Study of Earth's atmosphere and climate
    • Hydrology: Study of Earth's water resources
  • Physics: Study of matter and energy
  • Engineering: Application of matter and energy for human use
  • Chemistry: Study of chemicals and their interactions
    • Biochemistry: Study of the chemistry of living organisms
    • Geochemistry: Study of the chemistry of materials like rocks, soil, and waste
  • Social Science: Study of human populations
    • Geography: Study of relationships between populations and Earth's features
    • Anthropology: Study of the interactions of biological, cultural, geographical, and historical aspects of humankind
    • Sociology: Study of human population dynamics and statistics

Environmental Issues and Example

• Example illustrating the interconnectedness of various fields:
  • A community decides to use coal for electricity (economics).
  • Coal is mined from underground (geology).
  • Coal is transported (engineering).
  • Burning coal releases air pollution (chemistry).
  • Pollution forms acid in the atmosphere (chemistry).
  • Acid rain affects plants (ecology).
  • Pollution regulations are implemented (politics).

Our Environment Through Time

• Humans have impacted the environment throughout history:
  • Hunting
  • Agriculture
  • Settlement

Hunter-Gatherers

• Humans foraged for sustenance:
  • Collecting plants
  • Hunting animals
  • Scavenging remains
• They lived in tribes, using fire to manage prairies.
• They migrated seasonally to areas with abundant resources.

Early Environmental Problems

• Native American tribes and Aborigines utilized fire to drive animals (e.g., buffalo).
• They transported plants to new locations, introducing invasive species.

The Agricultural Revolution

• Agriculture began about 10,000 years ago, leading to the domestication of plants and animals.
• This revolution greatly impacted human populations by:
  • Increasing population size
  • Causing resource depletion
  • Leading to pollution
  • Contributing to biodiversity loss

Resource Depletion

• Natural resources are materials used by humans, classified as:
  • Renewable: Can be replaced rapidly (e.g., timber, water)
  • Nonrenewable: Replenished extremely slowly or not at all (e.g., coal, oil, minerals)
• Resource depletion occurs when the rate of resource use exceeds the rate of replenishment, resulting in pollution and waste.

Major Environmental Problems

• Resource Depletion:
  • The large human population (8.2 billion globally, 118.2 million in the Philippines) requires significant resources.
  • Nonrenewable resources are finite and subject to depletion.
  • The estimated remaining coal reserves are sufficient for about 250 years at current consumption rates.
• Pollution:
  • Pollution is a degradation or undesired change in air, water, or soil that affects the health of living organisms.
  • Biodegradable pollution: Can be broken down naturally.
  • Nondegradable pollution: Does not break down (e.g., plastics, mercury, lead).

Loss of Biodiversity

• The number of species on Earth is estimated in the tens of millions.
• Biodiversity refers to the variety of species within an ecosystem.
• Extinction is a natural process, but human actions can accelerate it.
• Loss of biodiversity is a concern due to human dependence on other organisms for food, oxygen, etc.
• Five major extinction events have occurred in Earth's history, with the most recent one (65 million years ago) causing the disappearance of 75% of species.
• Extinction normally occurs at a slow rate (background rate), but human activities are accelerating it.