Reviving Dead Zone Quiz Black Sea

A  No

B  Yes

A  Mussels release too many nutrients.

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

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

D  Mussels eliminate all other animals that can live there.

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

B  All of these

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

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

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

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

B  All of these

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

D  Eutrophication

A  Nothing can be done to restore the area

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

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

A  3 days

B  Its entire life

C  40 days

D  20 days

E  7 days

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  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.

D  It occurs when plankton die and thus all who need them die

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  Its causing the diatoms to outnumbered other ocean creatures

D  Gelatinous organisms eat all the diatoms

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

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

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

B  The spill of chemicals that block plant growth.

C  A drop in the salinity of the ocean.

D  A rapid rise in the pH of water.

A  1,000 square kilometers

B  20,000 square kilometers

C  10,000 square kilometers

D  40,000 square kilometers

E  100,000 square kilometers

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

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

C  An area where all the fish have been caught