energy flow and biochemical cycles

ecosystem

a community of living organisms and their interactions with their abiotic (nonliving) environment

equilibrium

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

resistance

the ability of an ecosystem to remain at equilibrium spite of distrubances

resilience

the speed at which an ecosystem recovers equilibrium

each organism occupies a ______ _________

trophic level

primary producer

the bottom of the food chain, usually photosynthetic organisms

primary consumer

consumes the primary producer

secondary consumers

usually carnivores that eat the primary consumers

apex consumer

the highest-level consumer in the ecosystem

decomposers

feed on dead-decaying organisms

_______ capture light energy and CO2 to produce sugars through photosynthesis

producers

chemical energy and nutrients are then passed to _______

consumers

________ recycle nutrients by breaking down organic matter (cellulose) and releasing carbon and other nutrients back to the environment

decomposers

holistic

ecosystem model attempts to quantify the composition, interaction, and dynamics of entire ecosystems; it is the most representative of the ecosystem in its natural state

mesocosm

experimental systems usually involve either partitioning a part of a natural ecosystem that can be used for experiments

microcosm

recreating an ecosystem entirely in an indoor or outdoor laboratory environment

a conceptual model

consists of flow charts to show interactions of different compartments of the living and nonliving components of the ecosystem

an analytical model

uses simple mathematical formulas to predict the effects of changes on ecosystem structure and dynamics

a simulation model

uses complex computer algorithms to model ecosystems and to predict the effects of changes

photoautotrophs

such as plants, algae, and photosynthetic bacteria, serve as the energy source for a majority of the world’s ecosystem

chemoautotrophs

synthesize complex organic molecules, such as glucose, for their own energy, usually they do its without sunlight and rather use other sources of energy

heterotrophs

acquire energy from digesting living or previously living organisms

biomass

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

gross primary productivity

The rate at which photosynthetic primary producers incorporate energy from the sun

net primary productivity

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

tropic level transfer efficiency

the measurement of energy transfer efficiency between two successive trophic levels

net production efficiency

allows organisms of a particular trophic level to incorporate the energy they receive into biomass

biomagnification

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

biogeochemical cycles

depict the recycling of inorganic matter between living organisms and the environment

water cycle

Water from the land and oceans enters the atmosphere by evaporation or sublimation, where it condenses into
clouds and falls as rain or snow. Precipitated water may enter freshwater bodies or infiltrate the soil. The cycle
is complete when surface or groundwater reenters the ocean

carbon cycle

Photosynthesis converts carbon dioxide
gas to organic carbon, and respiration cycles the organic carbon back into carbon dioxide gas. Long-term storage
of organic carbon occurs when matter from living organisms is buried deep underground and becomes fossilized

nitrogen cycle

Nitrogen enters the living world from the atmosphere via nitrogen-fixing bacteria. This nitrogen and
nitrogenous waste from animals is then processed back into gaseous nitrogen by soil bacteria, which
also supply terrestrial food webs with the organic nitrogen they need.