Understanding the Biosphere and Ecosphere: Ecosystem Dynamics

The Biosphere and Ecosphere

The biosphere is the life zone of the Earth, which includes all living organisms and all organic matter. The biosphere is the living component of the ecosphere. The ecosphere includes the large-scale ecosystems of the world. An ecosystem refers to the organisms that live in a particular area, the relationships between them, and their physical environment, such as a lake or a field.

Biomes

Biomes are the large-scale ecosystems of the world.

Ecosystem Components

Animals in terrestrial ecosystems obtain oxygen from the air, while animals in aquatic ecosystems obtain it from the water. Ecosystems consist of two main components:

• Biocenosis: The set of living beings in the ecosystem, including animals, plants, and microorganisms. Biotic factors are the effects that other organisms have on a living being in its environment.
• Biotope: The inorganic part of the ecosystem, or the physical environment. Abiotic factors are the physical and chemical elements in an ecosystem that affect living organisms.

How Living Things Obtain Food

All living things need energy to perform their vital functions. They obtain this energy from the nutrients in food. The way they obtain food determines their trophic level (their place in the food chain):

• Producers: Living beings that make their own organic matter from carbon dioxide, water, and mineral salts. They use energy from the Sun during photosynthesis. This is known as autotrophic nutrition (e.g., plants, algae).
• Consumers: Living beings that cannot produce their own organic matter. They feed on organic matter produced by other beings and transform it into their own. This is known as heterotrophic nutrition. There are three types of consumers:
  • Primary consumers: Herbivores that feed on producers.
  • Secondary consumers: Carnivores that feed on primary consumers; some are omnivores.
  • Tertiary consumers: Feed on primary and secondary consumers; some are omnivores.
• Decomposers: Living beings that decompose organic matter into inorganic matter. Producers then use this inorganic matter in the process of photosynthesis.