Soil

Question 1

What percentage of global carbon do soils store, and how does this compare to the carbon stored in the atmosphere and terrestrial vegetation?

Answer 1

Soils store 20-30% of global carbon, which is 2 times the carbon in the atmosphere and 3 times that of terrestrial vegetation.

Question 2

How does the carbon storage in arid soils compare to that in colder regions?

Answer 2

Arid soils store significantly less carbon, about 30 tonnes per hectare, compared to 800 tonnes per hectare in colder regions.

Question 3

What type of soils tend to store more CO2, clay-rich or sandy soils?

Answer 3

Clay-rich soils tend to store more CO2 than sandy soils.

Question 4

Over what period since the 1850s has there been a loss of carbon from soils, and how much carbon has been lost?

Answer 4

Since the 1850s, 40-90 billion gigatonnes of carbon have been lost from soils.

Question 5

How much carbon could be absorbed each year by improving farming techniques in half of the world’s agricultural soils by just 1%?

Answer 5

Improving farming techniques to store 1% more carbon in half of the world’s agricultural soils could absorb 31 gigatonnes of CO2 each year.

Question 6

What is the estimated cost to restore 40,000 hectares of degraded farmland in Kenya?

Answer 6

Estimates suggest it would cost $1 million to restore 40,000 hectares of degraded farmland in Kenya.

Question 7

According to UN estimates, what percentage of the world’s farmland is currently degraded?

Answer 7

According to UN estimates, about 40% of the world’s farmland is now degraded.

Question 8

What are some examples of better farming methods to enhance soil carbon storage?

Answer 8

Better methods include changing crop rotation, planting cover crops, direct drilling, establishing hedgerows, and growing native grasses.