Chapter 12

Question 1

Biogeochemistry

Answer 1

Biotic controls on the chemistry of the environment and the geochemical control of the structure and function of ecosystems.

Question 2

Source-sink

Answer 2

Source: producer of an element

Sink: sites of such storage of an element

Question 3

Radiative forcing

Answer 3

The difference between sunlight absorbed by the Earth and energy radiated back to space.

Question 4

Residence time

Answer 4

For material flowing through a volume, the residence time is a measure of how much time the matter spends in it.

Question 5

Methanogenesis

Answer 5

Methane produced by bacteria when oxygen is absent.

Question 6

Carbon cycle

Answer 6

Warmer water holds less CO2 than cold water.

A portion of the carbon in the atmosphere is absorbed in terrestrial and marine sinks, the rest remains in the atmosphere.

CO2 in the water becomes carbonic acid, and results ocean acidification.

Question 7

Methane cycle

Answer 7

Methane is a more potent greenhouse gas, per molecule, than CO2.

Increasing temperature results in permafrost thaw which releases methane.