Ocean 115 - Introduction to Oceanography » Spring 2022 » Reviving Dead Zone Quiz Black Sea

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Question #1
What is a dead zone?
A.   A burial ground for dead animals no longer useful on a farm
B.   An area of hypoxia or where there is too little oxygen in the water causing organisms to die
C.   An area where all the fish have been caught
Question #2
What is the size of the dead zone off the Danube River?
A.   40,000 square kilometers
B.   100,000 square kilometers
C.   20,000 square kilometers
D.   1,000 square kilometers
E.   10,000 square kilometers
Question #3
What is eutrophication?
A.   A rapid rise in the pH of water.
B.   The spill of chemicals that block plant growth.
C.   A drop in the salinity of the ocean.
D.   The over enrichment of the sea by nutrients that allow plants to grow.
Question #4
What are the three ways humans drive excess nitrogen into coastal waters?
A.   Rising fossil fuel use, bykill, and the construction of sewage systems drive excess nitrogen into coastal waters.
B.   Rising fossil fuel use, mass breeding of food animals and intensive farming, and bykill.
C.   Rising fossil fuel use, mass breeding of food animals and intensive farming, and the construction of sewage systems drive excess nitrogen into coastal waters.
D.   Nuclear energy use, mass breeding of food animals and intensive farming, and the construction of sewage systems drive excess nitrogen into coastal waters.
E.   Overfishing, bykill, and thermo luminescience.
Question #5
Is the increase of excess nitrogen into coastal waters a global problem?
A.   Yes
B.   Not yet but models predict it will be in 50-100 years
C.   No
Question #6
Why is the increase of gelatinous organisms and the subsequent swamping of the diatoms a problem?
A.   Diatoms are toxic and they destroy all food webs
B.   This is a problem because diatoms become outnumbered by small or less digestible types of species and gelatinous organism reduce the efficiency of the food chain causing fish stocks to drop.
C.   Gelatinous organisms eat all the diatoms
D.   Its causing the diatoms to outnumbered other ocean creatures
Question #7
Describe how the process of “tropic cascading” develops?
A.   It occurs when fishing vessels catch all members of one species and then catch all members of another.
B.   An imbalance of the food chain worsened by immense fishing. The hunting of a top predator results in rising numbers of smaller fish eating more zooplankton and leading to more phytoplankton.
C.   It occurs when plankton die and thus all who need them die
D.   An imbalance of the food chain worsened by immense fishing. The hunting of a top predator results in rising numbers of zooplankton and less phytoplankton.
Question #8
How long can a clam survive low oxygen conditions?
A.   7 days
B.   20 days
C.   40 days
D.   Its entire life
E.   3 days
Question #9
What is most critical thing required so that dead zones can be restored?
A.   Dead zones can be restored by reducing the nutrient delivery from nearby lands
B.   Nothing can be done to restore the area
C.   Dead zones can be restored by adding nutrients from the land to the water.
Question #10
What factors delay recovery?
A.   All of these
B.   Dearth of nearby healthy populations of marine plants & animals that can provide the seed stock
C.   River catchments that store high amounts of nutrients dissolved  ingroundwater or trapped in soils
D.   Eutrophication
Question #11
What steps must governments take to tackle the problem of dead zones?
A.   All of these
B.   Governments must make sure economic development does not lead to resurgence of nutrients into the sea. 
C.   Governments have to reduce the intensity of commercial fishing activities.
D.   Comprehensive plans must be in place in order to prevent nitrogen and phosphorus from getting into the water. 
E.   Landmark iniatives to maintain runoff nutrients also need to be put into effect. 
Question #12
What causes the partial and failed comeback of the mussels?
A.   Mussels eliminate all other animals that can live there.
B.   Mussels filter water but bacterial decomposition consumes as large amount of oxygen. The end result is the mussels collapse from low oxygen.
C.   Mussels use so little oxygen that once the nutrients fall other animals out compete them and cause the mussels to collapse.
D.   Mussels release too many nutrients.
Question #13
Can we just expect nature to absorb our waste?
A.   Yes
B.   No

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