Ch 42 - ecosystems and energy

law of conservation of mass

matter cannot be created or destroyed

detritvores/decomposers

fungi and prokaryotes

detritus

nonliving organic matter

primary production

the amount of light energy made to chemical energy by autotrophs during a period of time

gross primary production (GPP)

total primary production

net primary production (NPP)

GPP minus energy used by primary producers for autotrophic respiration

limiting nutrient

the element that must be added for production to increase in an area. nitrogen and phosphorus most often limit marine production

eutrophication

caused by the addition of large amounts of nutrients to lakes

secondary production

the amount of chemical energy in food converted to new biomass during a period of time

production efficiency

the fraction of energy stored in food that is used for secondary production

trophic efficiency

the percent of production transferred from one trophic level to the next, on avg 10%

biogeochemical cycles

nutrient cycles; involve both biotic and abiotic components