Ecological succession

ECOLOGICAL SUCCESSION

^v   Ecological succession is defined as, “A change in the community in which new populations of organisms gradually replace existing ones”.

^v   There are two types of ecological succession:

1) Primary Succession

^v   Occurs where there is no soil, e.g. after a volcanic eruption or a glacial retreat.

^v   “Pioneer organisms”

^v     Simple plants first – no or shallow roots.

^v    Gradual influx of more complicated and larger plants as the habitat changes

^v   Unfavorable for life at first.

^v   Ends with a “climax community” – ecosystem stays constant, provided there are no changes in abiotic influences.

2) Secondary Succession

^v   Community development in the areas that were previously occupied by a other community.

^v   Occurs after a disturbance. E.g., loss of trees after disease, Fire or wind, deforestation etc.

^v   Conditions are favorable for as soil and nutrients are already present.

^v   More rapid than primary succession.

Primary Succession Vs Secondary Succession

Ecology

Study of the distribution and abundance of organisms, the flows of energy and materials between abiotic and biotic components of ecosystems.

Ecosystem

The living things in a given area, non-living chemical and physical factors of their environment, linked together through nutrient cycle and energy flow.