Functioning Ecosystems Flashcards
Food Chain
Simple linear arrangement of organisms showing the flow of matter and energy from one organism to another through feeding relationships.
Consumer
Organism that eats other living organism (or part of an organism) for nutrition.
Productivity
Amount of energy fixed in organic compounds; measured by increase of biomass per unit of time.
Photosynthetic Efficiency
The fraction of light energy that plants and algae convert into chemical energy during photosynthesis.
Gross Primary Production
The total amount of organic matter in an ecosystem produced as a result of photosynthesis.
Net Primary Production
Amount of energy available for herbivores in an ecosystem.
Specialist Feeder
A heterotroph that can thrive only on a limited diet.
Generalised Feeder
A heterotroph with a varied diet.
Detritus
Organic Debris from decomposing plants and animals.
Detritivore
An organism that feeds on detritus.
Decomposer
An organism (e.g. bacteria and fungi) that utilises dead organisms or waste matter for its nutrient, releasing simple inorganic molecules.
Trophic Level
A feeding level in a food chain e.g. producer, herbivore.
Food Web
All the possible feeding relations in an ecosystem.
Law of Conservation of Matter and Energy
Matter and energy cannot be created or destroyed but can be changed to other forms.
Ecological Pyramid
A model of the relationships between different organisms in a food chain.
Pyramid of Numbers
A model of the numbers of organisms at each trophic level of a food chain.
Pyramid of Biomass
A model of the amount of living matter transferred through a food chain.
Pyramid of Energy
A model of the amount of energy transferred through food chains.
Standing Crop
Biomass of an organism at any particular moment.
Biogeochemical Cycles
Circulation of chemical elements in the biosphere.
Nutrient Cycle
Cycling of a particular element between biotic and abiotic ecosystem components.
Reservoir Pool
Large abiotic component of a biogeochemical cycle in which matter is slowly exchanged with organisms.
Cycling Pool
Small compartment of a biogeochemical cycle with active exchange of matter between organisms and the environment.
Upwelling
Upward movement of deep, cold water to replace warm surface water.
Guano
Sedimentary rock, rich in phosphates, formed from the build-up of sea birds excreta.
Nitrogen Fixation
Conversion of atmospheric nitrogen to nitrate by bacteria and cyanobacteria.
Nitrifying Bacteria
Bacteria that convert ammonia to nitrite and nitrite to nitrate.
Denitrifying Bacteria
Bacteria that convert nitrate to nitrite, or atmospheric nitrogen or nitrite to ammonia.
Keystone Species
A species that has a disproportionately large effect on its environment relative to its abundance by maintaining local biodiversity within a community either by controlling populations of other species that would otherwise dominate the community or by providing critical resources.
Umbrella Species
Species selected when making decisions about conservation because they are representative of other species, and protecting them indirectly protects other species in the same habitat.
Flagship Species
A species chosen to raise support for biodiversity conservation in a chosen place or context.
