Earth’s Life Support Systems: The Water And Carbon Cycles In Contrasting Locations - Amazon Rainforest And Alaskan Tundra

Question 1

How large is the Amazon rainforest?

Answer 1

6 million square kilometers - which is the world’s largest rainforest

Question 2

What are the temperature conditions in the Amazon like?

Answer 2

25 to 30 degrees celsius average annual temperatures, with small seasonal temperature variation

Question 3

What are the weather conditions in the Amazon like?

Answer 3

High average annual rainfall of 2000mm which is convectional (stays in place), no dry season and significant cloud cover

Question 4

How much precipitation is recycled by evapotranspiration in the Amazon?

Answer 4

50-60%

Question 5

Describe the effects on the water cycle of the Amazon

Answer 5

10% of precipitation is intercepted, evapotranspiration rates are high, run-off is rapid and lots of water is stored in the soil

Question 6

How much carbon does the Amazon absorb each year?

Answer 6

2.4 billion tonnes

Question 7

Why are carbon exchanges fast in the Amazon?

Answer 7

As warm humid conditions allows for high rates of decomposition and photosynthesis

Question 8

What is the NPP of the Amazon?

Answer 8

2500 grams of carbon per meter squared a year

Question 9

How does rock lithology affect stores and flows of water in the Amazon?

Answer 9

As porous and permeable rocks such as limestone and sandstone stores water

Question 10

How does relief affect stores and flows of water in the Amazon?

Answer 10

As most of the Amazon basin has a gentle relief that allows water to move faster as overland and through flow

Question 11

How much deforestation occurred in the Amazon between 1970 and 2013?

Answer 11

17,500km squared per year, almost a fifth of the primary forest

Question 12

How does deforestation in the Amazon affect stores and flows of water?

Answer 12

Run-off will become even faster, raising flood risks, and high humidity will no longer be sustained leading to permanent climate changes

Question 13

How does deforestation in the Amazon affect stores and flows of carbon?

Answer 13

The carbon biomass stores will greatly decrease, as grasslands holds little carbon and the burning of trees causes huge flows of carbon to the atmosphere

Question 14

What are the three ways to manage the water and carbon cycles in the Amazon?

Answer 14

The protection of rainforest through legislation, reforesting degraded areas and improving agricultural techniques

Question 15

How much rainforest is Brazil committed to restoring?

Answer 15

120,000 square kilometers by 2030

Question 16

How much of the Amazon has been national parks, wildlife or indigenous reserves since 2015?

Answer 16

44%

Question 17

How does improved agricultural techniques help to manage the water and carbon cycles?

Answer 17

Diversifying crops maintains soil fertility, or recreating ‘dark soil’ could allow farming to be intensive, permanent and productive

Question 18

How large is the Alaskan Tundra?

Answer 18

8 million square kilometers across northern Canada, Alaska and Siberia

Question 19

What are the temperatures and weather like in the Alaskan tundra?

Answer 19

Mean annual precipitation and temperatures are low, with mean temperatures below -15 degrees celsius and winter temperatures going below -40 degrees celsius

Question 20

How much annual precipitation is there in the Alaskan tundra?

Answer 20

Less than 100mm

Question 21

What are the rates of evapotranspiration in the Alaskan tundra?

Answer 21

Both are low due to a short growing season and the subzero temperatures almost year round

Question 22

How much carbon does permafrost hold globally?

Answer 22

1600 GT of carbon

Question 23

When is carbon and water flux in the Alaskan tundra highest?

Answer 23

In the summer months, as the active layer thaws and small plants start growing

Question 24

What is the NPP in the Alaskan tundra?

Answer 24

200g/square meter/year

Question 25

How does human activity affect the water and carbon cycles in the Alaskan tundra?

Answer 25

Oil and gas production causes localised permafrost melting, due to an urban heat island effect, which in turn releases large amounts of carbon and water previously stored in the permafrost

Question 26

How can effects on the water and carbon cycles in the Alaskan tundra be managed?

Answer 26

Constructing buildings or infrastructure on piles or insulated gravel pads reduces heating affects on the permafrost, and advanced drilling and prospecting techniques reduces the need for exploration wells and additional oil drilling sites, which reduces permafrost impact