Reviving Dead Zone Quiz Black Sea

A  Yes

B  No

A  Mussels filter water but bacterial decomposition consumes as large amount of oxygen. The end result is the mussels collapse from low oxygen.

B  Mussels use so little oxygen that once the nutrients fall other animals out compete them and cause the mussels to collapse.

C  Mussels release too many nutrients.

D  Mussels eliminate all other animals that can live there.

A  All of these

B  Governments have to reduce the intensity of commercial fishing activities.

C  Landmark iniatives to maintain runoff nutrients also need to be put into effect. 

D  Comprehensive plans must be in place in order to prevent nitrogen and phosphorus from getting into the water. 

E  Governments must make sure economic development does not lead to resurgence of nutrients into the sea. 

A  Dearth of nearby healthy populations of marine plants & animals that can provide the seed stock

B  River catchments that store high amounts of nutrients dissolved  ingroundwater or trapped in soils

C  All of these

D  Eutrophication

A  Dead zones can be restored by adding nutrients from the land to the water.

B  Nothing can be done to restore the area

C  Dead zones can be restored by reducing the nutrient delivery from nearby lands

A  7 days

B  3 days

C  Its entire life

D  40 days

E  20 days

A  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.

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  It occurs when fishing vessels catch all members of one species and then catch all members of another.

A  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.

B  Diatoms are toxic and they destroy all food webs

C  Gelatinous organisms eat all the diatoms

D  Its causing the diatoms to outnumbered other ocean creatures

A  No

B  Yes

C  Not yet but models predict it will be in 50-100 years

A  Rising fossil fuel use, mass breeding of food animals and intensive farming, and the construction of sewage systems drive excess nitrogen into coastal waters.

B  Overfishing, bykill, and thermo luminescience.

C  Rising fossil fuel use, bykill, and the construction of sewage systems drive excess nitrogen into coastal waters.

D  Rising fossil fuel use, mass breeding of food animals and intensive farming, and bykill.

E  Nuclear energy use, mass breeding of food animals and intensive farming, and the construction of sewage systems drive excess nitrogen into coastal waters.

A  The over enrichment of the sea by nutrients that allow plants to grow.

B  A rapid rise in the pH of water.

C  A drop in the salinity of the ocean.

D  The spill of chemicals that block plant growth.

A  100,000 square kilometers

B  1,000 square kilometers

C  10,000 square kilometers

D  40,000 square kilometers

E  20,000 square kilometers

A  An area of hypoxia or where there is too little oxygen in the water causing organisms to die

B  An area where all the fish have been caught

C  A burial ground for dead animals no longer useful on a farm