48 terms

Ecology Terms

IB Biology HL Ecology Unit Review Terms
group of same species living in the same area at the same time
a form of plant sampling and calculating the density of plants in the area- divide into quadrats, count in certain quadrats, find average, multiply by all the quadrats
the pattern of spacing among individuals within the boundaries of a population ie clumped, random, or uniform
study of vital statistics of populations and how they change over time
a group of individuals from birth until all are dead
Type I
a species with few offspring but lots of parent involvement (k species) high population density
Type III
a species that produces many offspring with little parent involvement (r species) low population density
per capita birth rate
number of offspring produced per unit of time by an average member of the population
zero population growth
when births and emigration=deaths and immigration
carrying capacity
the maximum population an environment can sustain
"one shot" reproduction
repeated reproduction
intrinsic rate
maximum rate of growth
density independent
a birth/death rate that does not change with population density
density dependent
as density increases, the birth rate drops and the death rate increases
population dynamics
population fluctuations from year to year
ecological footprint
aggregate land and water area required to produce resources consumed and absorb waste generated
all the organisms that live together in a place and interact
ecological role
fundamental niche
full range of habitat, resource, etc
realized niche
the resources an organism ends up using in their fundamental niche due to competition with other organisms
interspecific competition
different species compete for resources
competitive exclusion
local elimination of inferior competitor
species diversity
variety of organisms in a community
species richness
number of species in a community
trophic structure
feeding between organisms
mass of all individuals in an ecosystem
dominant species
the species that is the most abundant with the greatest biomass in an ecosystem
keystone species
species that are not dominant but are important to ecosystem
remove/alter an organism due to fire, storm, etc.
ecological succession
disturbed area/species replaced by new species
primary succession
no soil for succession, starts with lichens and moss
secondary succession
ecological succession with soil to begin with
disease-causing organisms
sum of all organisms living in a given area and the abiotic factors with which they interact
primary producers
primary production
amount of light energy->chemical energy
gross primary production
total primary production (GPP)
net primary production
GPP subracted by energy used by producers for cellular respiratio
limiting nutrient
element that must be added for production to increase in an ecosystem
ecological impact of increase of cyanobacteria and algae in aquatic ecosystems due to an increase in the limiting nutrient (usually nitrogen or phosphorus)
secondary production
chemical energy in consumer food that is converted to their own new biomass
trophic efficiency
% of production transferred from one trophic level to the next (usually 5-20)
oxidation of ammonium in the soil to nitrite and nitrate
nitrogen fixation
reduction of atmospheric nitrogen to ammonia
process in which fixed nitrogen compounds are converted back into nitrogen gas and returned to the atmosphere
resource partitioning
the differentiation of niches that enables similar species to coexist in a community