8.9 Analyzing The Science

One important value of forest ecosystems is their capacity to store carbon, thereby keeping it out of Earth’s atmosphere and mitigating climate change. Intact ecological communities are better at performing this ecosystem service than degraded ones. All ecosystems can both take up carbon and emit it; it is the net difference between accumulation versus emission that tells us whether the ecosystem is a net sink or source of carbon to the atmosphere. Globally, terrestrial ecosystems are a major net sink for atmospheric carbon dioxide, storing about 1 metric gigaton of carbon per year. Wetlands store even more carbon than most forests, making wetlands extremely important carbon sinks.

CARBON ACCUMULATION IN DIFFERENT WETLAND SEDIMENTS

INTERPRETATION

Question 8.13

Which wetland type stores the most carbon? Which stores the least?

Question 8.14

What is the difference in carbon accumulation (in kg C per square metre per year) between temperate peatlands and prairie wetlands? Identify two possible reasons for this difference.

ADVANCE YOUR THINKING

Question 8.15

By what processes do ecosystems take up and emit carbon dioxide?

Question 8.16

What do the two wetland types with the highest carbon storage have in common? (HINT: What biome is represented by both?)

Question 8.17

If you had to decide what kind of wetlands to protect or restore in order to enhance carbon storage, which type of wetland would you prioritize? What challenges would you face in this effort?

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