abiotic nonliving components of the environment

aboveground biomass total mass of aboveground living plants per area

acid rain corrosive rain caused by rainwater falling to the ground through sulfur dioxide gas, turning it into weak sulfuric acid; can damage structures and ecosystems

age structure proportion of population members at specific age ranges

analytical model ecosystem model that is created with mathematical formulas to predict the effects of environmental disturbances on ecosystem structure and dynamics

apex consumer organism at the top of the food chain

aposematic coloration warning coloration used as a defensive mechanism against predation

assimilation biomass consumed and assimilated from the previous trophic level after accounting for the energy lost due to incomplete ingestion of food, energy used for respiration, and energy lost as waste

Batesian mimicry type of mimicry where a non-harmful species takes on the warning colorations of a harmful one

biogeochemical cycle cycling of mineral nutrients through ecosystems and through the non-living world

biogeography study of the geographic distribution of living things and the abiotic factors that affect their distribution

biomagnification increasing concentrations of persistent, toxic substances in organisms at each trophic level, from the primary producers to the apex consumers

biomass total weight, at the time of measurement, of living or previously living organisms in a unit area within a trophic level

biome ecological community of plants, animals, and other organisms that is adapted to a characteristic set of environmental conditions

biotic living components of the environment

biotic potential (rmax) maximal potential growth rate of a species

birth rate (B) number of births within a population at a specific point in time

camouflage avoid detection by blending in with the background.

carrying capacity (K) number of individuals of a species that can be supported by the limited resources of a habitat

chemoautotroph organism capable of synthesizing its own food using energy from inorganic molecules

climax community final stage of succession, where a stable community is formed by a characteristic assortment of plant and animal species

commensalism relationship between species wherein one species benefits from the close, prolonged interaction, while the other species neither benefits nor is harmed

competitive exclusion principle no two species within a habitat can coexist when they compete for the same resources at the same place and time

conceptual model (also, compartment models) ecosystem model that consists of flow charts that show the interactions of different compartments of the living and non-living components of the ecosystem

conspecifics individuals that are members of the same species

dead zone area within an ecosystem in lakes and near the mouths of rivers where large areas of ecosystems are depleted of their normal flora and fauna; these zones can be caused by eutrophication, oil spills, dumping of toxic chemicals, and other human activities

death rate (D) number of deaths within a population at a specific point in time

detrital food web type of food web in which the primary consumers consist of decomposers; these are often associated with grazing food webs within the same ecosystem

ecological pyramid (also, Eltonian pyramid) graphical representation of different trophic levels in an ecosystem based of organism numbers, biomass, or energy content

ecology study of interaction between living things and their environment

ecosystem community of living organisms and their interactions with their abiotic environment

ecosystem dynamics study of the changes in ecosystem structure caused by changes in the environment or internal forces

Emsleyan/Mertensian mimicry type of mimicry where a harmful species resembles a less harmful one

endemic species found only in a specific geographic area that is usually restricted in size

environmental disturbance change in the environment caused by natural disasters or human activities

equilibrium steady state of an ecosystem where all organisms are in balance with their environment and each other

eutrophication process whereby nutrient runoff causes the excess growth of microorganisms, depleting dissolved oxygen levels and killing ecosystem fauna

exponential growth accelerating growth pattern seen in species under conditions where resources are not limiting

all and spring turnover seasonal process that recycles nutrients and oxygen from the bottom of a freshwater ecosystem to the top

fallout direct deposit of solid minerals on land or in the ocean from the atmosphere

food chain linear representation of a chain of primary producers, primary consumers, and higher-level consumers used to describe ecosystem structure and dynamics

food web graphic representation of a holistic, non-linear web of primary producers, primary consumers, and higher-level consumers used to describe ecosystem structure and dynamics

foundation species species which often forms the major structural portion of the habitat

grazing food web type of food web in which the primary producers are either plants on land or phytoplankton in the water; often associated with a detrital food web within the same ecosystem

gross primary productivity rate at which photosynthetic primary producers incorporate energy from the sun

heterospecifics individuals that are members of different species

holistic ecosystem model study that attempts to quantify the composition, interactions, and dynamics of entire ecosystems; often limited by economic and logistical difficulties, depending on the ecosystem

host organism a parasite lives on

hydrosphere area of the Earth where water movement and storage occurs

intraspecific competition competition between members of the same species

island biogeography study of life on island chains and how their geography interacts with the diversity of species found there

J-shaped growth curve shape of an exponential growth curve

keystone species species whose presence is key to maintaining biodiversity in an ecosystem and to upholding an ecological community’s structure

logistic growth leveling off of exponential growth due to limiting resources

mesocosm portion of a natural ecosystem to be used for experiments

microcosm re-creation of natural ecosystems entirely in a laboratory environment to be used for experiments

mutualism symbiotic relationship between two species where both species benefit

Müllerian mimicry type of mimicry where species share warning coloration and all are harmful to predators

net consumer productivity energy content available to the organisms of the next trophic level

net primary productivity measurement of the energy accumulation within an ecosystem, calculated as the total amount of carbon fixed per year minus the amount that is oxidized during cellular respiration

net primary productivity and heat loss energy that remains in the primary producers after accounting for the organisms’ respiration

net production efficiency (NPE) measure of the ability of a trophic level to convert the energy it receives from the previous trophic level into biomass

non-renewable resource resource, such as fossil fuel, that is either regenerated very slowly or not at all

ocean upwelling rising of deep ocean waters that occurs when prevailing winds blow along surface waters near a coastline

one-child policy China’s policy to limit population growth by limiting urban couples to have only one child or face the penalty of a fine

parasite organism that uses resources from another species, the host

pioneer species first species to appear in primary and secondary succession

population growth rate number of organisms added in each reproductive generation

primary consumer trophic level that obtains its energy from the primary producers of an ecosystem

primary producer trophic level that obtains its energy from sunlight, inorganic chemicals, or dead and/or decaying organic material

primary succession succession on land that previously has had no life

relative species abundance absolute population size of a particular species relative to the population sizes of other species within the community

residence time measure of the average time an individual water molecule stays in a particular reservoir

resilience (ecological) speed at which an ecosystem recovers equilibrium after being disturbed

resistance (ecological) ability of an ecosystem to remain at equilibrium in spite of disturbances

S-shaped growth curve shape of a logistic growth curve

secondary consumer usually a carnivore that eat primary consumers

secondary succession succession in response to environmental disturbances that move a community away from its equilibrium

simulation model ecosystem model that is created with computer programs to holistically model ecosystems and to predict the effects of environmental disturbances on ecosystem structure and dynamics

species richness number of different species in a community

subduction movement of one tectonic plate beneath another

symbiosis close interaction between individuals of different species over an extended period of time that impacts the abundance and distribution of the associating populations

tertiary consumer carnivore that eat other carnivores

thermocline layer of water with a temperature that is significantly different from that of the surrounding layers

trophic level position of a species or group of species in a food chain or a food web

trophic level transfer efficiency (TLTE) energy transfer efficiency between two successive trophic levels

zero population growth steady population size where birth rates and death rates are equal