Soils (yr1)

Question 1

Contour ploughing

Answer 1

Ploughing along contours of land in order to minimise soil erosion

Question 2

Desertification

Answer 2

Fertile land becomes desert typically as a result of a drought, deforestation or inappropriate agriculture

Question 3

Edaphic

Answer 3

Of, produced by or influenced by the soil

Question 4

Mulching

Answer 4

Treat or cover with mulch

Question 5

Multi cropping

Answer 5

Growing two or more crops in the same piece of land in the same growing seasons instead of one crop

Question 6

Ploughing

Answer 6

Turn up the earth with a plough especially before sowing

Question 7

Sedimentation

Answer 7

The process of settling or being deposited as a sediment

Question 8

Soil compaction

Answer 8

Stress applied to soil causes densification as air is replaced or displaced by the soil

Question 9

Soil structure

Answer 9

Arrangement or way soil is arranged

Question 10

Soil texture

Answer 10

Determines soil classes based on physical texture

Question 11

Soil fertility

Answer 11

Ability of soil to sustain plant growth

Question 12

Strip cropping

Answer 12

Cultivation in which different crops are sown in alternate strips to prevent soil erosion

Question 13

Surface runoff

Answer 13

Flow of water occurring on the ground when excess water can no longer sufficiently rapidly infiltrate in soil

Question 14

Terracing

Answer 14

A sloped plain cut into a series of successively receding steps

Question 15

How does Thermal Capacity affect different soil types?

Answer 15

Clay soils retain water easily. Water has a higher thermal capacity so theses soils warm up and down slowly compared to sandy soils

Question 16

How does Drainage affect different soil types?

Answer 16

Sandy soils - large pores so good water drainage

Clay particles - smallest pores so slower drainage

Question 17

How does Aeration affect different soil types?

Answer 17

Sandy soils have larger particles with greater pore spaces so they have higher air content

Question 18

How does Nutrient Levels affect different soil types?

Answer 18

Sandy soils - rapid drainage causes leaching of nutrients

Clay soils - clay particles have a negative surface charge so positively charged mineral ions stick to their surface

Question 19

How does Root Penetration affect different soil types?

Answer 19

Sand particles are looser because of the lack of adhesion by surface water so they allow better penetration.

Question 20

How does Capillary Action affect different soil types?

Answer 20

Tiny pore spaces between clay particles allow water underground to rise towards the surface.
There is no capillary action/rising in sandy soils

Question 21

How does ploughing/drainage affect soil fertility?

Answer 21

Could increase fertility as allows aeration (which speeds up decomposition) of soil and can reverse compaction, aiding drainage

Question 22

How does compaction affect soil fertility?

Answer 22

Decrease

Less infiltration, reduced root penetration

Question 23

How does Irrigation affect soil fertility?

Answer 23

Increases

Adds water

Question 24

How does pH control affect soil fertility?

Answer 24

Increases

Adds lime/chalk/buffer solution to make optimum pH to stop nutrient leaching

Question 25

How does pH control affect soil fertility?

Answer 25

Increases | Adds lime/chalk/buffer solution to make optimum pH to stop nutrient leaching

Question 26

What is the optimum pH of soil?

Answer 26

5.5 - 7

Question 27

How does fertillisers affect soil fertility?

Answer 27

Increase Inorganic - adds nitrates/phosphates Organic - adds carbon

Question 28

What is splash erosion?

Answer 28

Raindrops falling and hitting bare soil and disturbing the soil structure. Particles are dislodged and move into the pore spaces, reducing infiltration.

Question 29

What is surface runoff?

Answer 29

Water erosion that dislodges particles and moves them elsewhere. If there is a loss of root binding (e.g. after deforestation) then there is a likelihood of landslides following heavy rainfall

Question 30

What is wind erosion?

Answer 30

The removal of fertile soil from the land and a formation of dune systems. More common in dry areas of low rainfall. Particles are moved across the surface by the wind; small ones are picked up and moved long distances. Agricultural soils are most at risk when exposed without plant cover.

Question 31

What are 5 natural features that reduce soil erosion?

Answer 31

1. Raindrops impact is reduced by vegetation cover (interception) 2. Natural vegetation acts as a windbreak 3. Vegetation and other soil biota increase infiltration rates, so reduced surface runoff 4. Soil organic matter binds the soil particles together 5. Roots binding the soil together

Question 32

Universal soil loss equation (usle) is given in exams but need to be able to understand it

Answer 32

``` Erosion rate = RxKxLxSxCxP Where: R = Rainfall erosivity factor K = Soil erodibility factor L = Slope length factor S = Slope gradient factor C = Cropping management factor P = Erosion preventing factor ```

Question 33

7 human activities causing soil erosion?

Answer 33

1. Clearing vegetation e.g. removing hedgerows 2. Cultivating on steep slopes 3. Loss of soil biota 4. Ploughing vulnerable soils 5. Overgrazing of cattle 6. Compaction from heavy machinery e.g. tractors 7. Deforestation = less interception

Question 34

How is a landslide caused?

Answer 34

When soil becomes wet, increased mass and lubricated with a lack of vegetation and root binding causes land movement. More at risk after heavy rainfall.

Question 35

How is sedimentation caused?

Answer 35

Soil particles are carried into rivers due to surface run off. Increased turbidity and particles downstream can lead to reduced river volume. The river is at risk of flooding

Question 36

How is desertification caused by soil erosion?

Answer 36

Loss of soil fertility leads to less vegetation growth. | less vegetation = more erosion and less rainfall

Question 37

How is desertification caused by soil erosion?

Answer 37

Loss of soil fertility leads to less vegetation growth. | less vegetation = more erosion and less rainfall