Unit 2.3 Flashcards
trophic level
refers to the position of an organism within a food chain
food web def
connects more than one food chain, and is a very complex. it shows how everything is connected to each other
food chain def
linear diagram of what eats what
source food web def
links are drawn upward from a species that is a basal resource
sink food web def
links are drawn downward from a species that is considered a top predator
community food web def
considers a group of species in an area and identifies all the trophic links btwn the species
3 different types of food webs
source, sink, community
top down model postulates what
that predation controls community structure
bottom up model postulates what
that nutrients control community structure as they control primary producers
diversity def
a function of richness and evenness
richness def
the number of different types or components
species richness def
the number of differnet species
evenness def
the relative abundance of all the different types or components
biodiversity used most ocmmonly to refer to what
is used in reference to the species richness of a system
ecological def of biodiversity
the richness and evenness among organisms and the ecological complexes in which they occur
3 types of diversity
structural, functional, genetic
structural diversity def
the richness and evenness amound different types of components in a system
functional diversity def
the richness and evenness of differnet roles played by all the different components within a system
genetic diversity def
the richness and evenness of genotypes within a particular population or species
ecological redundancy def
when two or more different species perform a similar function
what is the shannon wiener diversity function used to compare
diversities among communities
shannon wiener diversity equation
H= sum of (Pi)(log10(Pi))
H
index of species diversity
S
number of species
Pi
proportion of total belonging to the i the species
the higher the H, what
the greater the uncertainty and the higher the diversity
what does diverstity provide an ecosystem
stability, making it less vulnerable to collapse
diversity-stability hypothesis is what
a straight 1:1 linear progression
rivet hypothesis is what
based on ecological redundancy. is more of a slow gradual slope, steep at first but then decreases..
redundancy hypothesis is what
based on a few critical species, this one is steep at first and increases but then plataues.
idiosyncratic hypothesis is what
the idea that the relationship between stability and diversity is different for every community
