2.2: Introducing Ecosystems
pg. 32
Key Concepts:
5. Ecosystems are composed of biotic and abiotic components.
Evidence of Learning: Students can …
- identify and describe an ecosystem.
- identify biotic and abiotic factors in an ecosystem.
- explain why an ecosystem is sustainable or unsustainable.
Introducing Ecosystems
Ecosystem: all the living organisms and their physical and chemical environment.
Biotic Factors: living things, their remains, and features, such as; nests, associated with
their activities.
Abiotic Factors: the non-living physical and chemical components of an ecosystem.
- Living organisms that share regions and interact with each other (biotic) and their
external non-living environment (abiotic), are found in ecosystems.
- Examples of non-living factors (abiotic) are; water, rock, temperature, wind, weather,
air, and sunlight.
- Examples of living factors (biotic) are; plants, animals, bacteria, other micro-organisms
and once living organisms and their remains.
- Organization of Ecosystems; species, populations, and communities.
Figure 3: An ecosystem is composed of populations of plant and animal species and their
biotic and abiotic environments.
Describing Ecosystems
- consists of various sizes, and combinations of biotic and abiotic features.
- All ecosystems are characterized by their distinct set of features.
See Table 1: Examples of large and small ecosystems, page 34
Sustainability of Ecosystems
Sustainable Ecosystem: an ecosystem that is maintained though natural processes.
Sustainable: the ability to maintain ecological balance.
- When ecosystems maintain a relative constant set of characteristics over long periods of
time.
- The human population negatively impacts the sustainability of ecosystems and causing
the ecosystem to become unsustainable.
- Humans can also create sustainable ecosystems, but these are artificial, and need to be
maintained by humans.
- Humans are also affected by changes in their biotic and abiotic environments.
Check Your Learning
Questions 1 – 7, page 35
Summary:
- Ecosystems are characterized by their biotic and abiotic factors.
- Biotic factors are living components of an ecosystem. Abiotic factors are the non-living
physical and chemical components.
- A population is all individuals of the same species living in an ecosystem.
- A community is all organisms living in the same ecosystem.
- Natural ecosystems are generally sustainable, whereas artificially created ecosystems
must usually be managed.
- Surrounding ecosystems influence many aspects of our daily lives.