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parent material – материнська або residual soil – безструктурний грунт;
корінна порода елювій
bottomland - заплава saturated – заболочений, просичений
вологою
precipitation – опади; випадання опадів steepness - крутість
interdependent -взаємозалежний unconsolidated – пухкий; той, що не
затвердів
soak in – всмоктатись, просочитись

Task 2. Read the text. Translate it into Ukrainian. Talk about soil formation
controls.

Controls of Soil Formation
Soil is the product of the complex interplay of several factors. The most
important of these are parent material, time, climate, plants and animals, and
topography. Although all of these factors are interdependent, their roles will be
examined separately.
The source of the weathered mineral matter from which soils develop is called
the parent material and is a major factor influencing a newly forming soil. Gradually it
undergoes physical and chemical changes as the processes of soil formation progress.
Parent material might be the underlying bedrock, or it can be a layer of unconsolidated
deposits, as in a stream valley. When the parent material is bedrock, the soils are termed
residual soils. By contrast, those developed on unconsolidated sediment are called
transported soils.
Time is an important component of every geological process, and soil formation
is no exception. The nature of soil is strongly influenced by the length of time that
processes have been operating. If weathering has been going on for a comparatively
short time, the parent material strongly influences the characteristics of the soil. As
weathering processes continue, the influence of parent material on soil is overshadowed
by the other soil-forming factors, especially climate.
Climate is the most influential control of soil formation. Just as temperature and
precipitation are the climatic elements that influence people the most, so too are they the
elements that exert the strongest impact on soil formation. Variations in temperature and
precipitation determine whether chemical or mechanical weathering predominates. They
also greatly influence the rate and depth of weathering.
Plants and Animals. The biosphere plays a vital role in soil formation. The
types and abundance of organisms present have a strong influence on the physical and
chemical properties of a soil. In fact, for well-developed soils in many regions, the
significance of natural vegetation in influencing soil type is frequently implied in the
description used by soil scientists. Such phrases as prairie soil, forest soil, and tundra
soil are common.
Topography. The lay of the land can vary greatly over short distances. Such
variations in topography can lead to the development of a variety of localized soil types.
Many of the differences exist because the length and steepness of slopes have a
significant impact on the amount of erosion and the water content of soil. On steep
slopes, soils are often poorly developed. In such situations little water can soak in; as a
result, soil moisture may be insufficient for vigorous plant growth. Further, because of
accelerated erosion on steep slopes, the soils are thin or nonexistent. In contrast,
waterlogged soils in poorly drained bottomlands have a much different character. Such
soils are usually thick and dark. The dark color results from the large quantity of
organic matter that accumulates because saturated conditions retard the decay of
vegetation.

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