ecology Flashcards
population definition
the number of organisms of the same species living in the same area
biodiversity definition
all the organisms that are interdependent on eachother and the environment in which they live eg living organisms in a rainforest
habitat definition
the area where and organism lives
community definition
the number of organisms of all the species living in the same area
decomposer definition
an organism that gains energy by feeding on dead organisms and breaking them down eg fungi and bacteria
biotic factor
living factors that may affect the distribution of organisms eg predation of mice by owls, competition for sunlight in a field of sunflowers
trophic level definition
the level of the food chain that the organism is feeding at. The producer is always at trophic level 1
food chain definition
shows what eats what in a community
food web definition
shows how food chains interact in a community
pyramid of biomass definition
shows the dry mass of individuals at each stage in a food chain
consumer definition
an organism that gains energy by eating another organism
abiotic factor definition
non living factors that may affect the distribution of plants and animals
examples of biotic factors
predation
food availability
competition
how is wind speed measured
an anemometer
how is ph measured
soil tests or a ph probe
how is light measured
light meter
how is temperature measured
thermometer
how is water/ moisture levels measured
weigh soil sample
dry sample in oven
reweigh sample
calculate change in mass
calculate the % of mass lost
how to calculate % soil moisture
change in mass/original mass X100
sampling method
-use quadrat
-place quadrat along line transect or use random sampling by throwing quadrat over the shoulder or using coordinates
-move quadrat and place at different distances
-use a key to identify species
-calculate percentage cover of species or count number of species
-record results
-repeat
what do food chains show
the feeding relationships which transfer energy and nutrients between several different organisms
what’s an issue with pyramids of numbers
they can be misleading as they don’t take size of the individuals into account 
name an advantage of pyramids of biomass over a pyramid of numbers
accounts for differing sizes of individual organisms, therefore giving a more accurate picture of energy in the ecosystem 
name an advantage of pyramids of numbers over pyramids of biomass
They are easier to calculate as you just count the number of individuals. You don’t need to kill them to calculate their dry mass and you do for biomass.
hi, is energy lost between the Sun and plant
-Light is reflected off of the leaf
-Light passes through the leaf and Mrs chloroplasts
-Light hits the ground rather than the leaf