6.3.1 ecosystems Flashcards
(44 cards)
what is an ecosystem
6.3.1(a)
all the living organisms and non-living conditions in an area
key word describing how ecosystems change over time
6.3.1(a)
dynamic
how are ecosystems dynamic
6.3.1(a)
-pathogens can arrive
-species may arrive or leave -imm or -emi gration
what are the 3 components of an ecosystem
6.3.1(a)
-habitat-physical location where organism lives
-population-all the organisms of one species
-community-all the populations of all the species living in an ecosystem
what is the role of each species in an ecosystem called
6.3.1(a)
niche
what is a biotic factor and name some examples
6.3.1(a)
living
eg-predation, competition and hunting
what is a abiotic factor and name some examples
6.3.1(a)
non-living
eg-light, temperature and pH
what are the 3 different types of dynamic changes an ecosystem can face
6.3.1(a)
-cyclic changes-changes repeat themselves in a predictable rhythm
-directional changes-they go in one direction and are irreversible
-unpredictable/erratic-dont have a particular direction and cant be predicted
How can biomass be calculated experimentally
6.3.1(b)
- collect sample of your species
2.dry it in an oven at 80 degrees to remove water then measure the dry mass - multiply dry mass to reflect dry mass of total population size.
what is a producer also known as
6.3.1(b)
photoautotroph
how do producers create their own energy
6.3.1(b)
using light energy from the sun however only a small amount is converted into biomass
what are the units for biomass
6.3.1(b)
energy per area of habitat per time
kj m-2 year-1
give 3 reasons all the light energy isnt converted to biomass in producers
6.3.1(b)
- light may not hit a chloroplast
2.it may be the wrong wavelength of light so be reflected
3.other factors eg-low CO2 may limit rate of photosynthesis
how can you calculate biomass efficiency
6.3.1(b)
biomass efficiency=biomass present in higher trophic level/biomass present in previous trophic level x 100
what is gross production
6.3.1(b)
total amount of energy used to form biomass
what is net production
6.3.1(b)
total amount of biomass after respiration
what is net production
6.3.1(b)
net production=gross production - respiratory losses
name 3 reasons why all the biomass isnt transferred from producers to consumers
6.3.1(b)
- some of the organism won’t be digested
Eg-may not be able to digest the cellulose cell wall of the plant
2.energy is lost through faeces and urine - energy is lost in respiration
how can you improve ecosystem efficiency
6.3.1(b)
simply food chains by removing competeing organisms
reduce respiratory losses
eg-reducing reliance on repsiration to keep them warm by having a heater
what is carbon fixation
6.3.1(c)
when producers take in CO2 for photosynthesis and use it to make organic carbon containing compounds
how do producers and consumers release CO2 back into the environment
6.3.1(c)
respiration
how are organic C containing compounds passed along the food chain
6.3.1(c)
when consumers eat producers
what is decomposition
6.3.1(c)
when producers and consumers die organic C containing compounds remain in waste matter when broken down by decomposers this releases CO2 back into the environment
what is combustion
6.3.1(c)
waste matter that isn’t decomposed is converted into fossil fuels which can be burnt to produce CO2
