functioning ecosystems Flashcards
biomass
total mass of living matter (organic matter) in an ecosystem
producers (autotrophs)
organisms that photosynthesise
trophic level
a level in the food chain of an ecosystem based on feeding relationships
heterotrophs (consumers)
organisms that cannot photosynthesise and must consume other organisms for food
trophic levels in a food chain
producer (autotroph) ->
herbivore (primary) ->
omnivore or carnivore (secondary consumer) ->
omnivore or carnivore (tertiary consumer)
specialist
a heterotroph that can thrive on a limited diet
eg. koala and eucalyptus
generalist
a heterotroph with a varied diet
scavenger
feed on animals they have not killed themselves
do producers have arrows going into them?
no
food webs
show all the possible feeding relationships between organisms in an ecosystem
food chain
simple linear arrangement of organisms showing the flow matter and energy from one organism to another through feeding relationships
energy transfer in a food chain
- show the energy flow within an ecosystem
- at each step, there is a loss of energy
what happens at each tropic level in an food chain?
a proportion of the available energy is either used to fuel the needs of an organism or lost due to inefficiencies
how is energy lost throughout a food chain?
- heat loss due to metabolism
- loss of chemical energy in uneaten portions of an organism
- loss of chemical energy in waste
energy (trophic) efficiency
the energy produced by an organism occupying a particular trophic level is divided by the energy available from the previous trophic level
percentage efficiency formula
(net productivity of the organism / net productivity of the previous trophic level )× 100
energy flow diagrams
map the path of the sun’s energy as it transfers through the trophic levels of an ecosystem and is transformed into heat by metabolism
what do the arrow in an energy flow diagram indicate?
the direction of energy flow and are labelled with the from and quantity they carry
what do the boxes in an energy flow diagram indicate?
the trophic levels in an sequence
ecological pyramids
represent the amount of energy, biomass, or number of individuals at each trophic level
three types of ecological pyramids
pyramid of numbers,
pyramid of biomass,
pyramid of energy
pyramid of numbers
shows the number of individual organism at each trophic levelling an food chain
pyramid of biomass
shows the total mass of living matter at each level in an food chain. collects data at a particular point in time
pyramid of energy
shows the amount of energy transformed through a food chain
carbon containing compounds
carbohydrates,
proteins,
nucleic acid,
nutrient cycles
cyclic movement of key chemical elements through the biotic and abiotic components of an ecosystem
biogeochemical
biological and geochemical components
two basic components of biogeochemical cycles
reservoir pool (sink) and cycling (exchange) pool
the water cycle
follows water molecules between the abiotic and abiotic components of an ecosystem, as well as the three states of matter, solid, liquid and gas
what water bodies does evaporation come from?
oceans, streams, lakes, and land
transpiration
loss (evaporation) of water from plants
surface run-off
rainwater stays on the surface and runs from higher to lower ground
percolation
water seeping into the deeper layers of the earth
infiltration
water seeping into the shallow layers of soil
define carbon
an essential compound of the organic molecules that make up and living organism
what does the carbon cycle digram display?
how carbon atoms circulate between the organic compounds of living things and their non-living surroundings through a number of pathways
define nitrogen
a key element in making proteins, including structural proteins and enzymes. plays an essential role in controlling cell activities and growth
nitrogen fixation - nitrifying bacteria
the conversion of atmosphere nitrogen gas to useable nitrogen compounds
nitrogen fixing bacteria
transform free nitrogen gas in the soil metabolic reactions to release ammonia/nitrate, which is transferred to the plants to form proteins
ammonification - decomposers
process of decomposers breaking down dead plants and animals, which are organic sources of nitrogen to produce ammonia
nitrification - nitrifying bacteria
bacteria that converts ammonia to nitrate and nitrate to nitrate. forms of nitrogen that can be absorbed and used by plants in the production of amino acids
denitrification - denitrifying bacteria
bacteria that converts nitrate to nitrate or atmospheric nitrogen, or nitrate to amino acid
ecological niche
the role and space that an organism occupies in an ecosystem, including all its interactions with the biotic and abiotic factors of its environment
fundamental niche
the widest potential niche that a species could ideally occupy without competitors, predators, or parasites
realised niche
the actual niche that a species occupies, given the restrictions place on it by interactions with other species
