4. Ecological Succession
• ecological succession:
transition from one biotic
community to another
• pioneer species: first to
colonize a newly opened area
• pave the way for other species
by improving conditions for
subsequent species - known as
facilitation
5. Ecological Succession
• climax ecosystem: when
there appears to be a dynamic
balance between all of the
species and the physical environment
• implies more stability than actually
occurs in nature
6. Succession
• succession - existing species taking advantage of available
niches
• disturbance constantly creates gaps or patches in the landscape
• enhances biodiversity
7. Primary Succession
• primary succession:
process of initial invasion
and progression from one
biotic community to the
next
8. Secondary Succession
• secondary succession:
when an area has been
cleared by fire, humans, or
floods and then left alone,
plants and animals from the
surrounding ecosystem may
gradually invade the area
• starts with pre-existing soil
9. Aquatic Succession
• aquatic succession:
when soil particles erode
from the land and settle out
in ponds or lakes, gradually
filling them in
• climax ecosystem may be a
bog or forest
10. Resilience
• resilience: ability of an ecosystem to return to normal after a
disturbance
• resilience mechanisms:
process of
replenishment of
nutrients, dispersion
of plants/animals,
rapid regrowth of
plant cover
11. Fire
• fire climax ecosystems:
ecosystems that depend on fires to
“reset” the ecological
“clock”
• major form of disturbance common
to terrestrial ecosystems
• create a patchwork of meadows and
forests at different stages that lead to
a more diverse environment
