Residual Soils

Residualsoilsarethoseformedinplacebythegradualdecayofparentmaterialwhencutthroughtheyshowagradualtransitionfromfreshrockuptodecayedrocktosubsoilandtopsoilresidualsoilsusuallyformslowlythedeepeningsoillayerprotectstherockbeneathfromfurtherchemicalactiontypesofresidualsoilsdependontherockfromwhichtheyformclimateandotherfactors.

Exercise 4. Read about different types of soils and decide which title is the most suitable for each text:

1. Tropical Red Soils, 2. Clay, 3. Transported Soils, 4. Northern Forest Soils

Text A. These soils are developed on parent material that has been moved by wind, water, or ice. Huge deposits of windblown silt serve as the parent material for the loess soils in the western prairies. In the Mississippi valley and along western streams are deposits of water-borne alluvial materials on which some very rich soils have formed. In northern states glacial debris is often the parent material.

Text B. These soils are well-developed, well-drained soils resulting from the deep leaching action of much rain and the chemical action of warm air. These may be residual soils of great thickness. The leaching and oxidation make poor soil which may be exhausted after a few years of cultivation. The fall of the Mayan civilizations has been attributed to soil exhaustion.

Text C. These soils illustrate different conditions from those above. These gray soils form under beds of spruce, pine, and fir needles which are acid in composition and decay slowly. The organic and inorganic materials mix poorly. Many of these soils of cooler regions have no been altered enough to make them good producers without special handling.

Text D. This soil was used by primitive men to make pottery not long after they first began to use stones as tools and weapons. After centuries of service, clay is still essential in many industries. About 35 million tons are mined annually and are used in bricks, pottery, chinaware, ceramic pipe, drilling muds, and for many other purposes. Clays are a mixture of silica, alumina, and water. Clay particles are small — less than 0.0001 inch. They stick together but are slippery when moist. Clays may come from granitic rocks, as a weathering product of the feldspars. They also form from weathered shales which came mainly from clay minerals originally. Clay deposits form on lake bottoms and in other quiet water, sometimes with annual layers (varves). One of the clay minerals is kaolin.

Exercise 5. Read the texts above once again and complete the following sentences:

1. In different parts of the country soils are formed of different parent material …

a. – sand, ice, and silt.

b. – windblown silt, water-borne alluvial materials, and glacial debris.

c. – glacial debris and ice.

2. The residual soils were formed by …

a. – leaching action and the chemical action of warm air.

b. – the exhausted cultivation.

c. – leaching and oxidation.

3. Soils under beds of spruce, pine, and fir needles are poor because …

a. – they haven’t been altered.

b. – they are found in cooler climates.

c. – of the rapid decay processes.

4. Clay is …

a. – a productive agricultural soil.

b. – a good producer without special handling.

c. – essential in many industries.

Exercise 6. Practice the reading of the following words and expressions and translate them into Russian:

nitrogen fixation, unwanted accumulation in the topsoil, plant growth, high levels of metal, primary nutrients, manure and fertilizer, soil and water contamination, significant losses in quality and growth, weight loss, petroleum-based products, transported from field to field by livestock, elevated salinity levels, soluble compounds, incorporated into the soil, nitrogen deficiencies

Exercise 7. Match the words on the left with their definitions on the right:

A. Nouns:

1. alkali a. liquid capable to dissolve other substances

2. tissue b. taking food or drink into a body

3. persistence c. any kind of liquid poured from a tank or container

4. toxicity d. stability

5. equilibrium e. plant without leaves, flowers, or roots

6. solvent f. poisoning

7. sawdust g. substance which combines with acid and neutralizes it to form a salt

8. ingestion h. a centre from where a disease could be spread further around

9. nursery i. ability to survive in severe conditions

10. manure j. fine wood fragments made in sawing

11. fungus k. substance of an animal body or plant

12. spillage l. animal excrement used as a fertilizer

B. Adjectives:

1. immobile a. being able to produce a copy of oneself

2. microbial b. unable to move

3. excess c. able to be dissolved

4. deleterious d. antagonistic or hostile

5. unanticipated e. being more than the permitted limits

6. adverse f. not suitable

7. reproductive g. being harmful

8. beneficial h. very intense or unpleasant

9. hydraulic i. unexpected

10. severe j. referring to tiny living creatures that could be seen only with a help of a microscope

11. soluble k. being very useful

12. inappropriate l. operated by pressure forced through a pipe by a liquid such as water

C. Verbs:

1. to tie up a. to separate or become separated into two or more pieces

2. to attain b. to pour from a container

3. to apply c. to remove or be removed from substance by liquid passing through it

4. to spill d. to include or be included as part of a larger unit

5. to restrict e. to put something on or into

6. to leach f. to link parts

7. to load g. to put to practical use

8. to release h. to achieve or to accomplish, to reach

9. to incorporate i. to set free, to let go or fall

10. to break down j. to confine to certain limits

Exercise 8. Check yourself. Match the English names of the following substances on the left with their Russian equivalents on the right:

1. nickel a. железо 2. manganese b. сера 3. zinc c. ртуть 4. nitrogen d. магний 5. mercury e. фосфор 6. carbon f. свинец 7. iron g. цинк 8. copper h. калий 9. lead i. танин 10. chromium j. смоляная кислота 11. magnesium k. хлор 12. boron l. аммиак 13. chlorine m. никель

14. molybdenum n. нитриты 15. phosphorus o. углерод 16. potassium p. азот 17. sulphur q. нитраты 18. calcium r. хром 19. tannin s. водород 20. resin acid t. бор 21. ammonia u. щёлочь 22. nitrates v. марганец 23. nitrites w. кальций 24. oxygen x. молибден 25. hydrogen y. кислород 26. alkali z. медь

Exercise 9. Read the following texts and match them with the titles below: