Lab 4 - Succession Flashcards
What is an ecotone?
It is a mixed community formed by the overlapping of adjoining communities in a transition area (transitional strip separating 2 communities)
What is edge effect?
It is the tendency for increased variety and organism density at community junctions as well as microclimate effects associated with changes from one community to another
What are edge species?
They are species particularly adapted to living in ecotones
What does ephemeral organisms mean?
it refers to organisms with short life cycles/growing seasons
What is basal area?
It is the cross section area of a stem of a plant or of all plants in a stand and is used to determine percent stocking
What is importance value?
It provides an overall estimate of the influence or importance of species in a community. It’s expressed as the sum of relative frequency, relative density, and relative dominance, divided by 3
What is dominance?
DBH is used to calculate basal areas of trees and so the total areas of the stems indicate the contribution of each species to the total biomass of the community.
What is relative dominance?
It is the basal area of a species divided by the sum of the basal areas for all species
What is density?
It is the count of individuals per unit area for each species
What is relative density?
It is the number of individual species divided by the sum density of all species, multiplied by 100
What is frequency?
It is based on how many points a species is found in, and provides an estimation of regularity occurence
What is relative frequency?
It is the frequency of species divided by the sum of frequencies of all species multiplied by 100
What is succession?
It is the sequence of replacement of one community by another until a relatively stable community occupies the area
What is primary succession?
It is the development of an ecosystem that begins on an area that has not been previously occupied by a community.
ex. newly exposed rock from former sea beds, lava, glacial retreat, etc
What is secondary succession?
it is the development of an ecosystem after an incomplete disturbance of an area that was previously occupied by another ecosystem
