Human Activites That Cause Soil Erosion And Degradation

Question 1

Why is vegetation removal causing soil loss

Answer 1

Removing vegetation leaves the soil exposed to the processes of wind and water erosion
There is no longer roots to bind the soil or organic matter to create the humus that hold the soil together

Question 2

What is the benefits of ploughing

Answer 2

Breaks up the soil allowing it to be aerated and easier for roots to grow

Question 3

What is the problem with ploughing

Answer 3

Breaks up the soils structure so the soil particles are no longer in larger clumps so are more at risk of soil erosion
Only disturbs upper layer while compacting the lower soil layers

Question 4

What is overgrazing

Answer 4

When there are too many animals on a the same land for an extended period

Question 5

What are the problems with overgrazing

Answer 5

Animals eat the vegetation so much there is nothing left to protect the soil from wind and water erosion
Animals also damage roots meaning the soil is no longer held together

Question 6

What is the job of soil biota

Answer 6

To break down organic matter

Question 7

What is the importance of organic matter

Answer 7

Improved soil structure making it less prone to soil erosion

Question 8

Why are worms important

Answer 8

Increase infiltration by aerating the soil reducing surface runoff

Question 9

What causes soil compaction

Answer 9

Farm machinery
Large herds of livestock

Question 10

What is soil compaction

Answer 10

When the pore spaces in the soil are squashed reducing aeration levels

Question 11

What is the problem with soil compaction

Answer 11

Creates an anaerobic environment so decomposition is reduced
Reduced soil infiltration increases soil erosion

Question 12

what was the cause of the 2014 Somerset flood

Answer 12

highly sedimented rivers which reduced the rivers capacity

Question 13

why did the Somerset flood occur (Human cause)

Answer 13

the rivers had not been extensively dredged for 20 years meaning flow was dramatically reduced

Question 14

what is sediment

Answer 14

loose deposited material

Question 15

what is the problem with soil erosion reaching a reservoir

Answer 15

means the reservoir has reduced storage capacity.
will require dredging which is costly and time consuming

Question 16

what are the positive of sediment reaching the ocean

Answer 16

increases the rate of delta formation

Question 17

what are the negatives of sediments reaching the ocean

Answer 17

Eutrophication- pesticides and nitrates causes algae bloom killing aquatic plants and the fish that rely on the plants for oxygen
Can settle on corals

Question 18

what are particles in the atmosphere called

Answer 18

known as atmospheric particles

Question 19

what is the problem with atmospheric particulates

Answer 19

most important causes of air pollution
can trigger asthma

Question 20

where is the production of atmospheric particulates most likely

Answer 20

flat and bare areas
dry and sandy soils

Question 21

what is desertification

Answer 21

occurs when productive but arid land turns to desert

Question 22

how can soil erosion increase the risk of landslides

Answer 22

1. erosion makes it difficult for plant growth, plant roots hold the soil together and absorb water reducing separation of soil
2. erosion creates channels that promote landslides

Question 23

what are long term crops? (definition)

Answer 23

crops that do not require planting every year once grown they can remain in the soil
no need to plough (break up the soil)
Usually large so act as a windbreak (windblow)

Question 24

what are some examples of long term crops

Answer 24

fruit trees, coffee, nuts (almond + walnuts)

Question 25

what is contour ploughing

Answer 25

where the field is ploughed at 90 degrees to the slope angle

Question 26

how does contour ploughing reduce soil erosion

Answer 26

water doesn’t flow all the way down the slope so the the soil remains relatively stationary

Question 27

what is tied ridging and what is needed for it to take place

Answer 27

on flat fields
involve planting crops in a criss-cross of intersecting ridges

Question 28

what are the positives of tied ridging

Answer 28

increases infiltration and reduces runoff.

Question 29

why are windbreaks used?

Answer 29

good solution to wind blow as they reduce wind velocity

Question 30

where does terracing occur

Answer 30

where the land is heavily sloped fields are cut into the slope to create a terrace

Question 31

what do they do the hold the soil in place (terracing)

Answer 31

build walls to hold and retain the soil

Question 32

what are the positives of terracing

Answer 32

helps in filtration as the terraces are flat allowing more time for water to be absorbed

Question 33

what is multicroppiing

Answer 33

growing more than one crop in a field

Question 34

what is strip cropping

Answer 34

wide strips by a tractor
strips are grown at 90 degrees tot eh prevailing wind reducing wind erosion

Question 35

what is mulching

Answer 35

addition of organic matter
decomposition of organic matter creates the humus layer

Question 36

why is the humus layer important

Answer 36

make soil particles stick together more effectively

Question 37

what is mulch

Answer 37

any material laid over the soil surface
bark, straw composted manure

Question 38

what is no tillage

Answer 38

no ploughing occurs seeds are instead drilled directly into the ground
prevents breaking of soil damaging its structure