Community ecology Flashcards
Principle of allocation
when resources are devoted to one use, they cannot be allocated to another
niche
the range of conditions a species lives in
fundamental niche
the range of physical conditions that a species can tolerate (defines habitat)
range of tolerance
the range of environmental conditions within which an organism can survive, grow, and reproduce
realized niche
the range of physical conditions that a species actually occupies, given the constraints of biotic interactions
treatment
transplant outside current range
control
transplant inside current range
range shift
occurs when the geographical location of a species changes its location
range expansion
the process by which species increase its geographical distribution, usually by moving into new areas where it was not previously found
range contraction
occurs when a species reduces its geographical distribution, either by withdrawing from certain areas or through local extinction
Competition
the interaction between two species that has a negative impact on both species involved (aka both populations decrease)
Exploitative competition
the indirect competition between individuals or species for limited resources within an environment
Interference competition
the direct interactions between individuals or species that impede access of competitors to essential resources
the competitive exclusion principle
states that if two species with identical niches compete then one will inevitably drive the other to extinction
Temporary co-existence
both species continue to live in an area, but at lower #’s (lower carrying capacity)
competitive exclusion
one of the species disappears from the area (usually not random - some species are better competitors than others)
niche partitioning
both species continue to co-exist but they diverge to occupy diff ecological niches (realized niche changes = type of character displacement)
foundation species
provide an ecological foundation for many other species, even though they might not benefit from the interactions
keystone species
species with a disproportionately large impact on its environment relative to its abundance or biomass
biomass
total mass of living organisms in a specific area
mutualism
+,+
consumption
+, - (predation, parasitism, herbivory)
commensalism
+, neutral
amensalism
-, neutral
food web
ecological network that shows who eats whom and how much, aka the trophic relationships (diagram)
trophic levels
a position in the food chain that represents a group of organisms sharing the same primary source of nutrition and energy
- primary producers
- primary consumers (herbivores)
- secondary consumers (omnivores, carnivores
- tertiary consumers (feed on secondary consumers, largest)
ecosystem services
goods and services humans derive from the natural ecosystem
humus
organic matter
