Midterm 2 Terms and Definitions Flashcards
(30 cards)
Character Displacement
Shift in one or both competing species resources use thereby decreasing niche overlap
Climax Community
A community that occurs in late succession and whose population remain stable until disrupted by disturbance
K SPECIES
Community
An association of interacting species living in particular area, often defined as all organisms living in particular area
competitive exclusion principle
a theory that states 2 species with similar ecology CANNOT coexist
disclimax community
community whose species composition is maintained through time by frequent disturbances, like drought or grazing
disturbance
any relative discrete event disputing an ecosystem, community, or population structure and changes resources, substrate availability or physical environment
equilibrium
state of balance in system which opposing factors cancel each other, stability is maintained by opposing forces such that populations altered by events quickly return to equilibrium state
facilitation model
model of succession which pioneer species modify environment in ways that it becomes less suitable for early successional species and more spottable for species characteristic of later successional stages
functional response
increase in animal feeding rate which eventually levels off, occurs in response to increase of food availability
gross primary production
total amount of NRG fixed by all photoautotrophs in ecosystem
gross secondary production
total amount of NRG entering tropic level through ingestion by consumers
handling time
total amount of time taken to chase, kill and digest a particular type of prey
inhibition model
model of succession that proposes that early occupants of an area modify environment in a way that makes area less suitable for both early and late successional species
insurance hypothesis
theory that increased diversity community stability due to an increased portability of there being some species present in the community able to cope with any particular disturbance
net primary production
gross amount of NRG from primary production minus amount of NRG lost via respiration by photoautotrophs
net secondary production
point of NRG energy trophic level through ingestion by consumer, minus NRG lost to reparation (heat), excretion and urine
numerical response
change in density of predator pop in reposes to increased prey density
optimal foraging theory
through that attempts to model how organisms feed as an optimizing process that maximizes or minimizes some quantity, like NRG intake or predate risk
Pioneer community
first community to become established following disturbance, with species commotion of community changing over time, typically composed of R SELECTED
pioneer plant communities
typically composed of species that can colonize bare rock, disperse over bast distances and can fix nitrogen
primary productivity
amount of NRG fixed by photoautotrophs per unit time- low NRG inorganic carbon to high NRG organic carbon product
primary succession
succession on newly exposed geological substrate, not significantly modified by organisms- ex. newly formed volcanic lava or on substrate exposed bu retreat of glaciers
resource partitioning
when species split or divide recourses to avoid or lessen competitive overlap
secondary production
assimilation of organic matter by heterotrophs to produce biomass
