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To sum it up, all the soil-forming factors descried above work together to form
soil. No single factor is responsible for a soil’s character. Rather, it is the combined
influence of parent material, time, climate, plants and animals, and topography that
determines this character.

Task 3. Look at Figure 10.2. Talk about the parent material for different
types of soil. Also note that as slopes become steeper, soil becomes thinner.

Task 4. Be ready to discuss the most important factors producing soil:
 parent material;
 time;
 climate;
 plants and animals;
 topography.

Individual work

Task 1. Read the information below. Did you know about it before?
D I D Y O U K N O W?
It usually takes between 80 and 400 years for soil-forming processes to create 1
cm of topsoil.

Task 2. Read the text and translate it into Ukrainian (in written form).
Build up a list of key terms to the text.
Soil Erosion
Soils are a tiny fraction of all Earth materials, but they are a vital resource.
Because soils are necessary for the growth of rooted plants, they are the foundation of
the human life-support system. Soils can be damaged or destroyed by careless activities.
Despite their basic role in providing food, fibre, and other basic materials, soils are
among our most abused resources. Perhaps this neglect and indifference has occurred
because a substantial amount of soil seems to remain even where soil erosion is serious.
Nevertheless, although the loss of fertile topsoil may not be obvious to the untrained
eye, it is a growing problem as human activities expand and disturb more and more of
Earth’s surface.
Soil erosion is a natural process. It is part of the constant recycling of Earth
materials that we call the rock cycle. Once soil forms, erosional forces, especially water
and wind, move soil components from one place to another. Every time it rains,
raindrops strike the land with surprising force. Water flowing across the surface carries
away the dislodged soil particles. Because the soil is moved by thin sheets of water,
this process is termed sheet erosion.
After a thin, unconfined sheet has flowed for a relatively short distance, threads
of current typically develop, and tiny channels called rills begin to form. Still deeper
cuts in the soil, known as gullies, are created as rills enlarge. When normal farm
cultivation cannot eliminate the channels, we know the rills have grown large enough to
be called gullies. Although most dislodged soil particles move only a short distance
during each rainfall, substantial quantities eventually leave the fields and make their
way downslope to a stream. Once in the stream channel, these soil particles, which can
now be called sediment, are transported downstream and eventually deposited
elsewhere.
In the past, erosion occurred at slower rates than it does today because more of
the land surface was covered and protected by trees, shrubs, grasses, and other plants.
However, human activities such as farming, logging, and construction, which remove or

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