QUESTIONS AND ANSWERS SURE A+
✔✔nutrients lose - ✔✔-they leave upper layer by:
a. organism die/excretion- sink to the sea floor can occur
b. harvesting/fishing- removes nutrients from the ecosystem
c. when nutrients have sunk to the bottom,they are considered lost. why? because
decomposition is very slow. why is decomposition slow at the bottom? it is cold and
there is less oxygen
✔✔human impact - ✔✔process in which human activity affects the cycles:
a. runoff- agricultural waste/chemical/fertilizer/pollutants wash into sea
b. dissolution- burning fossil fuels pollutants air then gases dissolve into water
c. harvesting/fishing- removal of nutrients
✔✔how do nutrients enter the surface water? - ✔✔1. dissolving or atmospheric
dissolution of carbon dioxide and nitrogen
2. runoff from land- rock gets weathered and minerals are carries via erosion
3. runoff from land from agricultural waste that wash into the sea
✔✔how do the nutrients get into the food chains? - ✔✔1.
assimilation/uptake/absorption- producers absorb nutrients from water
2. consumers either get the nutrients from what they eat or directly from the water
, ✔✔death/decomposition - ✔✔then they sink to sea floor and are either:
1. incorporated into reefs
2. or are compacted together through sedimentation to form rock
✔✔upwelling - ✔✔brings weathered minerals/nutrients back to the surface; happened at
the edge of landmass
✔✔harvesting/fishing - ✔✔by humans, takes nutrients out of the cycle
✔✔how to calculate change in a nutrient on a diagram with numbers - ✔✔first, identify
where you are calculating the change. then, identify which numbers are going in to the
area and which are going out. next, add up all the amounts of the arrows going in. ass
up alls the amounts of arrows going out. subtract the sums and that will be your answer-
the total amount of change in a nutrient in the area you were asked to calculate. do not
include any number for arrows which are nit directly touching the area in which you are
calculating.
✔✔how to calculate rate of change of amounts or concentration of nutrients on a graph
- ✔✔rate is the slope of a line, like in math, that means use the slope formula
✔✔atoll formation - ✔✔list the stages in the formation of an atoll
1. fringing reef develops on island
2. barrier reef forms
3. island subsides/sinks
4. atoll forms
✔✔atoll theory - ✔✔explain the Darwin-Dana-Daly theory of atoll formation
1. fringing reef forms at the edge of volcanic island
2. island subsides/sinks or sea level rises
3. reef grows forming barrier reef
4. island completely subsides/sinks
5. forming a lagoon around an atoll
evidence to support this theory
1. deep drilling examples Marshall Islands/Bikini Atoll
2. coral deposits
3. corals can only grow 50m below surface
4. carbon dating
5. corals live 30m-65m years old
6. soils on atoll relatively young. matches dates of post glacial periods; supports
hypothesis that sea level fall exposed reef platform
✔✔three methods used for the reconstruction of the history of coral reefs - ✔✔1. carbon
dating-the process of carbon dating: