exam 3 Flashcards
(25 cards)
a group or organisms that interact with each other are called?
a Community
species dominance is characterized by what 4 factors?
Density, biomass, largest energy flow, and most influence over rest of community.
How is the “importance value” calculated?
Relative Density + Relative Dominance + Relative Frequency
How is “Relative Density” calculated? (same for Dominance and Frequency)
Density of target species / Density of community
“species Density” is calculated how?
Number / Area
“Species Dominance” is calculated how?
Coverage / Area
“Species Frequency” Is calculated how?
Occurrences per plot / Total plots
what is “species Richness”?
total number of species in a community
What is “Species Evenness”?
abundance of individuals among species. how likely are you to encounter 1 species after another
what is a “Key Stone” species?
a species that has a major effect on community structure.
What is a “Food Web”?
feeding relationships within communities. (interlocking food chains become food webs)
A terrestrial structure is defined by what?
plant forms
an aquatic/marine structure is defined by what?
depth and motion of water.
vertical stratification of aquatic include profiles of what 3 aspects?
Temperature, light, and oxygen
how are aquatic environments stratified from top to bottom? (3)
Epilimnion -> Thermocline -> Hypolimnion
what is the “Benthic Zone”?
Bottom mud of an aquatic environment
what is the “Littoral Zone”?
shallow water with rooted plants: light touches bottom
what is the “Limnetic Zone”?
deep water, no rooted plants: light does not touch the bottom
what is the “Photic Zone”?
same as epilimnion: has light for plants to grow
what is the “Compensation Level”?
same as metalimnion: furthest light reaches
what is the “Profundal Zone”?
same as hypolimnion: not enough light for plants
what is the “ Autotrophic Layer”?
on top: fixes light and makes food
what is the “Heterotrophic Layer”?
eats food made by autotrophs: energy transfers: circulates nutrients via predation and decomposition
what does a “Sharp Boundary” imply?
species are found in distinct groups and have Rigid boundaries as you move across a landscape
