Notes on Biosphere, Ecosystems, and Biomes

Physical Science and Ecosystems Overview

  • General Concepts
    • This section will cover major themes in physical science, the biosphere, ecosystems, and biomes.

Biosphere

  • Definition: The biosphere is the sum of all living organisms on Earth and the environments in which they inhabit.
  • Components:
    • Living organisms (plants, animals, microorganisms)
    • The interactions among these organisms and their physical surroundings.

Ecosystem

  • Definition: An ecosystem encompasses a community of living organisms interacting with their physical environment.
  • Key Characteristics:
    • Includes all the biological (living) and abiotic (non-living) factors in an area.
    • Comprised of various habitats, biotic communities, and environmental variables.

Atmosphere

  • Definition: The atmosphere is a layer of gases that surrounds the Earth, essential for life.
  • Structure:
    • Composed primarily of nitrogen (approximately 78%) and oxygen (approximately 21%), with traces of other gases.
  • Role:
    • Provides necessary gases for respiration, influences weather patterns, and protects life from harmful solar radiation.

Lithosphere

  • Definition: The lithosphere consists of the upper layers of the Earth, including the crust and the rigid upper mantle.
  • Functions:
    • Provides solid ground for terrestrial life and contains minerals and resources essential for human activity.

Hydrosphere

  • Definition: The hydrosphere includes all of Earth’s water in all forms (liquid, solid, vapor).
  • Components:
    • Oceans, rivers, lakes, groundwater, and atmospheric moisture.
  • Importance:
    • Essential for sustaining life, facilitating biochemical processes, and regulating climate.

Biomes

  • Definition: A biome is a large geographic biotic unit, a major community of plants and animals with similar life forms and environmental conditions.
  • Types of Biomes:
    • Examples include tundra, desert, rainforest, grassland, and aquatic.
  • Factors Influencing Biomes:
    • Climate, geography, and available water resources.