The Dead Zone

Question 1

Based on the graphs, in which months could phytoplankton blooms occur in the Gulf?

Accepted Answer

August, September, and October

Question 2

Which of the following DO content would be considered "normal" and supportive of marine life?

Accepted Answer

6 mg/L

Question 3

Which correctly expresses the relationship between decomposition & dissolved oxygen?

Accepted Answer

Decomposition uses dissolved oxygen, removing it from water

Question 4

What human activity could lead to phytoplankton blooms?

Accepted Answer

waste water treatment, agriculture/fertilizer use, factory emissions, run off

Question 5

This term refers to an ecological imbalance caused by excess nutrients.

Accepted Answer

Eutrophication

Question 6

The term hypoxic means... (HINT: what is hypo-?)

Accepted Answer

DO content is less than 2-3mg/L, but still above zero

Question 7

An excess of which of the following would most likely be associated with dead zone formation ?

Accepted Answer

nitrogen

Question 8

The term anoxic refers to the absence of what molecule?

Accepted Answer

Oxygen gas

Question 9

D.O. content readings- Gulf of Mexico Aug-Nov '93. Which depicts the mostly anoxic conditions?

Accepted Answer

August

Question 10

In which month do you think eutrophication was not occurring?

Accepted Answer

November

Question 11

Typically dissolved oxygen is expressed in...

Accepted Answer

milligrams per liter

Question 12

Which graph depicts the most hypoxic conditions?

Accepted Answer

September

Questions 12