Sandy Shore Communities

Upper intertidal

drier habitat with crabs and birds

Lower intertidal

less dry habitat with clams and worms

gravel, sand, silt/clay, mud

sediment classified by size, biggest to smallest

wave action

what results in smaller grain sizes of sediment further away from shore

well sorted (coarse)

all large grain size so water drains quickly

greater O2 availability, animals dry faster

positives of well sorted (coarse)

less detritus, shifting rocks create instability

negative of well sorted (coarse)

well sorted (fine)

all small grain size, water drains slowly

more detritus builds up

positive of well sorted (fine)

harder to burrow, dries slower, less O2 available

negatives of well sorted (fine)

poorly sorted

all different grain sizes with little to no draining of water

dig-and-pull

muscular foot that expands and contracts to burrow in sediment

digging

moving particle grains out of the way, and sometimes eating it as they burrow

meiofauna

live between sediment grains due to small body size

bioturbation

burrowing activity that can alter the physical and chemical characteristics of sediments

siphon and increased hemoglobin

adaptations for animals to live within sediment

detritus (decomposing organic material)

main food source of organisms in sediment

primary and secondary producers

suspension feeders role