Vocabulary
What is a dead zone?
an area in water that has little to no oxygen
Name 4 spheres of the earth.
Biosphere, Geosphere, Hydrosphere, and Atmosphere
Name 4 biogeochemical cycles.
Water cycle, nitrogen cycle, carbon cycle, and phosphorus cycle
What nutrients are primarily responsible for causing algal blooms?
Nitrogen and phosphorus
What happens to marine life when a dead zone occurs?
They leave or die off.
What is a nutrient?
a substance that provides nourishment for life and growth
What does geo-, bio-, hydro-, and atmo- stand for?
Ground, life, water, air
What organism is the driving force in the nitrogen cycle?
Which human activity is the primary cause of dead zones?
agricultural runoff
How do dead zones impact human communities?
It decreases fisheries and tourism for coastal communities.
What is agricultural runoff?
runoff that contains nitrogen and phosphorus from fertilizing crops
Give an example of each of the spheres.
Ex: Geosphere - rocks
Biosphere - humans
Atmosphere - gases
Hydrosphere - lake
What can scientists monitor to detect dead zone formations?
nutrient levels and oxygen levels
How does eutrophication lead to the formation of dead zones?
excess nutrients cause algal blooms that deplete oxygen level when they decompose
Why would implementing better agricultural practices be a good solution for preventing dead zones?
It would reduce nutrient rich runoff getting into the water
_____________ is excess nutrients in a body of water which causes overgrowth of algae
eutrophication
Give an example of how the hydrosphere interacts with the geosphere.
Answers vary.
Ex: Rain lands on the geosphere.
What do decomposers use when they break down dead organic material?
Oxygen
How would strong ocean currents reduce the effect of dead zones?
strong ocean currents increase oxygen mixing in the water
What is the effect of dead zones on a food web?
It disrupts the food web by killing off important species
Agricultural runoff causes _________ which leads to the formation of _________ _________.
eutrophication, dead zones
What spheres are involved in the formation of dead zones? BONUS x2 if you explain it in terms of spheres.
All of them!
How do humans impact the nitrogen, phosphorus, and carbon cycles?
Fertilizers add unnatural amounts of N and P.
Burning fossil fuels adds extra CO2.
Why are estuaries (where a river meets the sea) the most at risk for dead zones?
They receive a lot of nutrient rich runoff from land
List two agricultural practices that would reduce the formation of dead zones.
Answers vary.
Less fertilizer, plant cover crops (buffer zones), increase biodiversity of crops