Figure 23.21: Winter flock of bearded reedling in their natural habitat of dense wetland
reeds, in Helsinki, Finland ( 6 )
Habitats can also be examined from a human point of view. Thus, it is the environment in
which humans live, work, recreate, and move about. Human habitat is the sum total of all
factors which constitute the total environment where humans live, work, and perform their
essential and day-to-day obligations.
Lesson Summary
- Anecosystemisanaturalunitconsistingofallthebioticandabioticfactorsfunctioning
together in an area. - Biotic factors include all living components of an ecosystem and abiotic factors are the
non-living chemical and physical factors in the environment. - There are six major abiotic factors.
- The niche concept is one of the most important ideas associated with ecosystems.
- If niche overlap occurs, then the competitive exclusion principle comes into play.
- The habitat is the area where a particular species, species population, or community
lives. - Habitat destruction is a major cause of population decrease, leading to possible extinc-
tion. - Both the ecosystem and habitat can be looked at from a human point of view.
Review Questions
- Give three examples of ecosystems.