Parameter Tree:
EARTH SCIENCE > BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > COMMUNITY STRUCTURE

Definition:
A community is a group of populations of plants and animals in a given
place or an ecological unit used in a broad sense to include groups of
various sizes and degrees of integration. Community structure can refer to
the physical structure or to the biological structure of a community. The
physical structure is what one sees when looking at a community. For
example, in a forest, a primary structure is imposed by large trees, and a
secondary structure is the understory trees and shrubs. Biological
structure involves species composition and abundance, temporal changes in
communities, and relationships between species in a community. 


Reference:
Adapted from Krebs, Charles K. Ecology - 4th ed. 1994. HarperCollins College
Publishers, New York, New York.