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Flashcards in Community Structure & Dynamics Deck (16)
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1

climax community

stable, final community that develops from ecological succession

2

keystone species

species w/ exceptionally great impact on other species in its ecosystem relative to its abundance
- removal/addition could change community structure

(ie) sea stars control mussel populations

3

disturbance

any strong, short-lived disruption to a community that changes distribution of living and/or nonliving resources
- usually occurs w/ predictable frequency (how often) & severity (how massive)

(ie) tree falling, forest fire, disease epidemics, short-term explosion in # of herbivores

4

disturbance regime

characteristic disturbances that affect a given ecological community
- includes how often it occurs
- includes what happens when it occurs

5

succession

gradual habitat recovery after environmental disturbance
- usually by a series of species
- species traits & interactions makes succession predictable
- history & chance contribute a degree of unpredictability to succession

6

primary sucession

gradual habitat recovery after disturbance removes all soil & orgs
- bare rock or gravel

(ie) glaciers, floods, volcanic eruptions & landslides initiate PS

COMPLETE RESET

7

secondary succession

gradual habitat recovery after disturbance removes some or all previous orgs but leave soil intact
- primary & secondary succession

(ie) fire & logging initiate SS

DELETE

8

pioneering species

species that appear first in recently disturbed areas

9

weed

any plant that adapts for growth in disturbed soils
- thrive @ start of SS

10

facilitation

early arriving species make conditions MORE favorable for later arriving speices

(ie) plants provide shade & nutrients that become organic matter

11

tolerance

early arriving species DO NOT EFFECT probability that subsequent species will become established

12

inhibition

early arriving species make conditions LESS favorable for establishment of later arriving species

inhibit = stop/prevent

13

attributes of community structure

(1) total # of species
(2) relative abundance of those species
(3) sum of interactions among all species
(4) physical attributes of community - biotic/abiotic

14

Fredrick Clements biological community view

biological communities = stable, orderly & predictable
- develop same community of species due to coevolution
- extensive interactions
- begin formation of climax community
- determined by climate & biotic factors

15

Henry Gleason biological community view

communities are not stable or predictable
- each should develop different communities
- determined by chance

16

reality of biological community views

balance btwn both views
- leans more to Gleason