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I. Read the text and find out the paragraphs about the results of using combined fertilizers.

 

FERTILIZATION

 

In spite of the increasing use of synthetic fertilizers in agricultural practice and the subsequent raise of crop yields, it is found generally that, to maintain a high level of inherent fertility, their use must be accompanied by periodic applications of bulky organic manure, either in the form of farm manure, compost, or other organic by-product, either of the farm or of certain industries.

The maintenance of high productivity depends on a number of factors: the soil must be in the optimum condition for crop growth and must be in a position to furnish both food and water; it must have a suitable reaction in the chemical sense, and it must contain no substances toxic to growth. It must be physically amenable to cultivation, resistant to forces of erosion, and the micro-flora and micro-fauna must be of a character to ameliorate the general chemical and physical properties of the soil and the soil-plant relationship. Any substance which when added to the soil brings about an improvement in any one of those directions could be considered as a fertilizer or manure using the terms in their widest sense, and it is in connection with these indirect benefits that organic manures are of such great importance in fertilizer practice.

As a source of plant food, farmyard manure contains all the important nutrients although their availability is variable. The potassium present is readily soluble and immediately available; the nitrogen is present in both available forms, and in compounds, which only slowly break down; the phosphate compounds also decompose slowly.

Whatever the type of soil, applications of manure can have a beneficial action upon the physical properties. Heavy soils can be made easier to work, and the aeration and drainage improved by means of the increased organic-matter content, whilst on sandy soils the moisture-holding capacity of the manure increases drought resistance, the binding effect of the organic matter controls erosion and the increased base-exchange capacity improves the power of the soil to retain plant nutrients. Soil colour will be darkened by the incorporation of humus, with an increase in the heat-absorbing power.

 

II. Find in the text the words with the similar meaning.

to check erosion, decrease in yields, to keep high fertility, to break down, to add, especially, the following crop

 

III. Find in the text all international words and translate them.

IV. In the second column select the words and the word combinations equivalent to those in the first one.

1. moisture-holding capacity 1.

2. heavy soils 2.

3. nutrients 3.

4. resistant to forces of erosion 4.

5. organic manure 5. 糿

6. crop yields 6.

7. synthetic fertilizers 7.

8. inherent fertility 8.

9. physically amenable 9.

10. farmyard manure 10.

11. beneficial action 11. ,

12. sandy soils 12.

V. Fill in the blanks in the given figures, explain the necessity of the soil fertilization.

 
 


VI. Answer the following questions:

1. How is it possible to maintain the high level of inherent fertility?

2. What factors does the maintenance of high soil productivity depend on?

3. What substance could be considered as a fertilizer or manure?

4. What important nutrients does farmyard manure contain?

5. What are the effects of the manure application for heavy and sandy soils?

 

VII. Read the text without the dictionary, divide it for paragraphs and give the name to each paragraph.

APPLICATION OF FERTILIZERS

 

Fertilizer must be put into the seedbed, where it will do most good to the young plant as it grows. This is done in two ways: a) fertilizer is spread on the seed-bed before the seed is sown and usually harrowed in; b) fertilizer is put in at the same time as the seed and usually near to it in the soil. Top-dressing means putting a fertilizer onto a growing crop. It is commonly done with nitrogen fertilizers on growing grain crops such as a spring dressing of sulphate of ammonia for a crop of winter wheat. If the nitrogen had been applied in the seedbed, most of it would be washed out during the winter. Lime and plant foods in fertilizers are not all used up in the year they are applied to the land. Some of the value is left over for a year or more and helps later crops.

GRAMMAR EXERCISES

I. Put up four questions of different types (general, special, disjunctive, alternative) to each sentence.

Model: Farmyard manure contains all the important nutrients.

1) Does farmyard manure contain all the important nutrients?

2) What does farmyard manure contain?

3) Farmyard manure contains all the important nutrients, doesnt it?

4) Does farmyard manure or chemical fertilizer contain all the important nutrients?

 

1. Soil must have a suitable reaction in the chemical sense.

2. Soil must contain no substances toxic to growth.

3. The potassium present is readily soluble and immediately available.

4. Applications of manure can have a beneficial action upon the physical properties.

5. Soil colour will be darkened by the incorporation of humus.

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