chap 14 Flashcards
Ecology
study of the interaction among organisms and between organisms and their environment
Population
all the individuals of a species in a given area
Basic census
all individuals counted (humans, trees)
Mark-recapture
some individuals trapped, marked released, note number of
marked individuals in later captures
clumped
high densities in resource-rich areas, low densities elsewhere
uniform
no compelling feature pushing individuals together or apart
Carrying capacity
he maximum number of individuals that can be supported indefinitely in a given environment
Density-dependent factors
actors that increase with population size
Growth Rate =
Death rate- Birth Rate
Net Primary Productivity
measures plant growth
Endangered Species Act (ESA)
law passed in 1973 to protect and encourage population growth of threatened and endangered species
Biodiversity
the entire diversity of living organisms in an area
Severe threats to Species loss
1) Loss or degradation of habitat
2) Introduction of non-native species
3) Overexploitation
4) Pollution
Species area curve
he number of species that a natural area of a given size can support
Eutrophication
is the excess growth of bacteria that depletes oxygen from the
water
Energy flow
only a small portion ( ~10%) of the energy in one level of a trophic pyramid be converted to biomass at the next level
Nutrient cycling
nutients that pass through a food web rarely leave the system
Commensalism
One partner benefits the other is neither harmed or helped
endemic species
a species that is native to where it is found.
niche
describes the role an organism plays in a community
