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From Wasteland to Farmland

I. Memorize the following words:

an aqueduct - акведук

a barrage - запруда, плотина

a dam - дамба, плотина

an embankment - насыпь, набережная

a sluice - шлюз

a system of basin irrigation - система орошения затоплением

ample - достаточный

surplus - излишний

to alter - изменять, переделывать

to drain - осушать

to distribute - распределять

to irrigate - орошать

to fashion - моделировать

to fertilize – удобрять

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From Wasteland to Farmland

Four thousand years ago. Queen Semiramis ruled over the Assyrians. On her tomb was inscribed: "I constrained the mighty river to flow according to my will and led its water to fertilize lands that before had been barren and without inhabitants." A thousand years before that, the first pharaoh. King Menes, had introduced a system of basin irrigation along the Nile, which with some improvements, still plays its part in Egyptian agriculture today. From China, Egypt, India, and Iraq, irrigation spread westward. When the Spaniards arrived in Mexico and Peru they found man-made water supply system which the Indians had been using for centuries.

One the whole, nature has given man an ample and dependable supply of water. It is a resource unchanged by time: falling as rain, it flows to the sea, then returns to the clouds, in an endless cycle. But its distribution on the earth varies enormously, and in general there is either too little or too much of it.

More than three quarters of the world's land has insufficient natural water for agriculture, and therefore requires irrigation. Some places have to be irrigated for part of the year only. Where there is too much water, the land must be drained. And so men call upon the civil engineer to drain and reclaim the marshes and the lowlands. They ask him to bring water to deserts and dry lands, and to store surplus water in the wet seasons for use in the dry seasons. To do this the engineer must alter and regulate great rivers, raise embankment, dams, and barrages, construct aqueducts and sluices, build vast reservoirs, and fashion many thousands of miles of canals and channels of every description.

Egypt's Nile Basin is a modern example of river control and irrigation on the grand scale. The Nile is a unique river than flows through waterless desert for most of its total length of nearly 3000 miles. The lives of thousands of people depend on the volume and regularity of its annual flood, brought down from its mountain sources Over many centuries, the Egyptians evolved the technique of basin irrigation, which means trapping part of the annual floodwaters within low earth embankments built beside the river. The Nile usually overflowed at the right time of year for planning crops. If the water arrived early or late, if they were much lower or higher than normal, then famine or flood threatened.

II. Answer the questions.

1. Why was it important for Queen Semiramis "to constrain the mighty rivers to flow" according to her will?

2. Who introduced the first system of basin irrigation? Does it still exist?

3. What cycle does natural water pass through?

4. Name the most important measures required for the regulation of water distribution.

III. Choose the sentences expressing the main idea of the text.

1. Water is one of the most important factors for the existence of a community.

2. More than three quarters of the world's land has insufficient natural water for irrigation.

3. Natural water distribution needs improving.

4. Nature has given man an ample supply of water.

5. The main task of civil engineers is to control natural water distribution.

IV. True or false. Correct the false statements.

1. The problem of water distribution is not acute.

2. Nature has given man an ample supply of water.

3. Less than a quarter of the world's land has insufficient water for agriculture.

V. Match the words with their definitions.

1. Embankment a. An artificial water course.

2. A barrage b. A canal through which water is conducted with the flow, regulated

by the means, of a valve.

3. An aqueduct c. A bank, raised to hold back water.

4. A dam d. A barrier to obstruct the flow of water, built across a stream.

5. A sluice e. A formation of an artificial obstruction in a water course to

increase the depth of the water.

6. A canal f. A conduct for conveying water from one place to another.

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