Term
|
Definition
|
Any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment.
|
|
|
Term
|
Definition
|
The pattern of change in community composition following a
disturbance. This is often repeatable and regular and will
result in a climax community.
|
|
|
Term
|
Definition
|
When disturbance strips away all
pre-existing living organisms exposes
bare substratum.
|
|
|
Term
|
Definition
|
When early colonizers in succession change the environment in such a way that helps the establishment of other species.
Example: Alders (In Pioneer Community and can help extract more
nitrogen and fix CO2) helping Spruce colonize an area.
|
|
|
Term
|
Definition
When a species changes the enviroment in such a way to help prevent the establishment of another species. |
|
|
Term
|
Definition
|
When organisms re-establish themselves
on disturbed sites where some organisms
survived said disturbance. (Hurricane of1938)
|
|
|
Term
|
Forest Disturbance in the Northeast
|
|
Definition
|
Without disturbance, stable forest communities often come to be dominated by just a few tree species: sugar maple, hemlock, and beech.
Big Canopy
Adults cast deep shade
Slow Growing
Seeds can grow in low light
|
|
|
Term
|
Definition
Grows opportunistically; fills in a gap
created by a natural disturbance.
Eg. Fills in the gap created by a falling tree. |
|
|
Term
Non-equalibrium Community |
|
Definition
Competitive exclusion may not have a chance to proceed
all the way to completion and thus more species are able to
coexist.
|
|
|
Term
Intermediate Disturbance Hypothesis
(Low Disturbance) |
|
Definition
Competitive exclusion occurs because there is not enough disturbance to increase species richness. |
|
|
Term
Intermediate Disturbance Hypothesis
(High Disturbance) |
|
Definition
Population rates fail to recover when there is frequent (high) disturbance. |
|
|
Term
|
Definition
The disruption of continuity in pattern or process, which then creates a pattern composed of smaller elements (a mosaic). |
|
|
Term
|
Alpha diversity
(Species evenness )
|
|
Definition
The number of species within a single location or community; this is local species richness.
SE: How equally distributed the number of species in a community are. |
|
|
Term
|
Definition
The total number of species in a region, across all communities or habitats. Includes multiple habitats in a defined region. |
|
|
Term
Beta diversity
(Between Habitat Diversity)
|
|
Definition
The habitat diversity or “turn-over” of species from one habitat to another.
Gamma/Alpha--> Regional # of Species/Local number of Species
|
|
|
Term
Key Premise of Island Biogeography Theory (IBT)
|
|
Definition
The species richness of an island or habitat patch represents a dynamic equilibrium between two processes: colonization by new species extinction of species on island
|
|
|
Term
|
Definition
A system in a steady state where the rate of loss is equal to the rate of gain. |
|
|
