Chapter 16: Community Structure Flashcards
A group of interacting plants and animals inhabiting a given area
community
Number of species in a given area
species richness
A component of species diversity index;
A measure of the distribution of individuals among total species occupying a given area
species evenness
Proportional representation of a species in a community or sample of a community
relative abundance
Population possessing ecological dominance in a given community and thereby governing type and abundance of other species in the community
dominant
A species whose activities have a significant role in determining community structure
keystone species
Movement of energy and nutrients from one feeding group of organisms to another in a series that begins with plants and end with carnivores, detrital feeders, and decomposers
food chain
Interlocking pattern formed by a series of interconnecting food chains
food web
Species that feed on no other species but are fed upon by others
basal species
Species that feed on other species, and they themselves are prey of other species
intermediate species
Species not subjected to predators;
They prey on intermediate and basal species
top predator (also called apex predator)
connectance
check the book
A measure of the average number of links per species in the food web
linkage density
A group of populations that utilize a gradient of resources in a similar way
guild
A collection of species that exploit the same array of resources or perform similar functions within the community
functional group
Functional classification of organisms in an ecosystem according to feeding relationships, ranging from first-level autotrophs through succeeding levels of herbivores and carnivores
trophic level
Uppermost layer of vegetation formed by trees;
Also the uppermost layer of vegetation in shrub communities or in any terrestrial plant community where the upper layer forms a distinct habitat
canopy
Growth of medium-height and small trees beneath the canopy of a forest;
Sometimes includes a shrub layer as well
understory
Lighted water column of a lake or ocean, inhabited by plankton
photic zone
A deepwater area of marine ecosystems below the depth of effective light penetration
aphotic zone
The area of the sea or lake bottom
benthic zone
Changes in the physical and biological structures of communities as one moves across the landscape;
Spatial changes in community structure
zonation
Idea that species, especially plant species, are integrated into an internally interdependent unit;
Upon maturity and death of the community, another identical plant community replaces it
organismic concept of community
Clements
check the book
The view, first proposed by H. A. Gleason, that vegetation is a continuous variable in a continuously changing environment;
Therefore, no two vegetational communities are identical, and associations of species arise only from similarities in requirements
individualistic or continuum concept of communities
Gleason
check the book
Applying principles of ecosystem development and function to the restoration and management of disturbed lands
restoration ecology
