Biology 4- what is an ecosystem?

?
  • Created by: Hannah
  • Created on: 27-03-13 15:08

Biosphere- the part of the Earth that is inhabited by living organisms.

Ecosystems- located within the biosphere

Abiotic component- physical and chemical factors like the climate and soil type

Biotic component- factors determined by organisms such as predation and competition.

Habitat- a habitat can be thought of literally as the place with a distinct set of conditions where an organism lives.

Population- a group of individuals of the same species found in an area.

Community- the various populations sharing a habitat or an ecosystem

If two species live in the same habitat and have exactly the same niche within the habitat- the same food source, the same time of feeding, the same shelter and so on- they will compete with each other.

The better adapted of the two species will, sooner or later, out- compete the other and exclude it from the habitat. Two species are able to occupy the same habitat only if they occupy different niches.

What determines which species occur in a habitat?

A particular species lives in a habitat because it is adapted and able to survive and reproduce there. Species that are outcompeted in a habitat can face extinction.

Abiotic factors (non living or physical)

- non living or physical factors including; solar energy input, climate (rainfall, wind exposure and temperature), topography (altitude, slope, aspect (which direction the land faces), oxygen availability, edaphic factors (soil pH, soil texture, soil type), pollution and catastrophes (earthquakes, floods).

Biotic factors (living factors)

Competition, grazing, predation and parasitism (all relationships whereby one organism benefits at the others expense), mutualism (relationship in which both partners benefit).

Intraspecific- competition within species

Interspecific- competition between species

Anthropogenic factors- those arising from human activity- can be either abiotic or biotic.example- wolf (predators) removed and intro of deer and sheep.

Adaptation for survival

Species survive in a habitat because they have adaptations that enable them to cope with both biotic and abiotic conditions in their niche.

Example:polar bear

-hunt seals by standing very still by waters edge.

- Mate in summer

- female builds…

Comments

No comments have yet been made