ENVIRONMENTAL SCIENCE 1.8 PRIMARY PRODUCTIVITY

IM PASSING

primary productivity

rate at which energy is converted to organic substances by photosynthesis produces.

secondary productivity

amount of chemical energy and biomass produce by heterotrophic organisms at a given location and at a specific time.

net primary productivity

difference between the total energy that is fixed by the autotrophic and the energy expensed as their respiration losses.

gross primary productivity

amount of carbon fixed during photosynthesis by all producers in the ecosystem, total rate of photosynthesis

herbivore

an organism that mostly feeds on plants

detritivore

an organism that eats dead or decaying animals as food

omnivore

an organism that eats plats and animals

carnivore

an organisms that mostly eat meat or flesh of animals

producer

an organism that creates its own food or energy

10% rule

average only 10 percent of energy available at one tropic level is passed on to the next

1st law of thermodynamics

energy can neither be created nor destroyed, only altered in form.

2nd law of thermondynamic

when energy is converted from one form to another, some energy is lost and efficiency decreases.

food chain

describes how energy and nutrients move through an ecosystem

food web

a complex net worth or interconnecting and overlapping food chains showing a relationship within a community.

trophic levels

position of an organism in the food chain and ranges

trophic casade

powerful indirect interaction that can control entire ecosystems

persistant organic pollutants

toxic chemical that adversely affect human health the environment around the world.

DDT

one of the earliest and most widelt used pesticides leading to widespread contamination of water and soil resources.