III Перепишите английские предложения, найдите и подчеркните в них зависимый или независимый причастный оборот. Переведите предложения на русский язык
1. Alkali soils being brought into production and soils that have accumulated salts through the use of high salt-content water require leaching.
2. Principal crops grown under irrigation are corn, alfalfa, and sorghums, corn being the most important.
3. The amount of fresh water being small, we must use fresh water efficiently.
4. A new irrigation system having been built, some water problems were solved.
IV Перепишите и письменно переведите на русский язык следующие
сложные предложения, подчеркните в каждом английском предложении придаточные предложения условия.
1. If sea water did not contain harmful substances, it would be used for irrigation or drinking purposes.
2. There are comparatively few regions where irrigation would not be profitable if it could be cheaply provided.
3. Improving irrigation would be much easier if we could see what is taking place
below the soil surface.
V. Прочитайте текст "Methods of Water Application ", письменно ответьте на вопросы:
1. What factors will influence the choice of irrigation methods?
2. What is the objective of irrigation?
Methods of Water Application
Many factors, including topography, source, amount, and quality of water supply, permeability of the soil, slope of land, method of distribution of the water to the irrigator, precipitation during the irrigation season and the crop growth will influence the choice of methods.
The only objective of applying water to the field is to supply sufficient moisture to meet the needs of the growing crop. The soil in which the crop grows is a storage reservoir. Application of water fills the storage space in the soil and makes water available to the plant through its root system.
Therefore, the objective of irrigation is to apply water uniformly throughout the root zone in sufficient quantities to meet the plant needs, without erosion, with a minimum amount of deep percolation, and with a minimum amount of surface runoff.
ТЕКСТЫ ДЛЯ АУДИТОРНОЙ РАБОТЫ
The Supply of Water
The total amount of water contained in our planet is constant and invariable and can neither be increased nor diminished. It assumes а variety of forms, such as the oceans, moisture vapour, fresh water, lake water of varying degrees of salinity, and ice. As most of this water is locked away in the oceans, in snow fields, ice caps and glaciers, only а sma11 proportion is available in а form readily usable by man. Moreоvег, а great deal of the water in and on the land is polluted by minerals or by industrial waste and so frequently rendered unusable.
Of the water contained in the oceans, а very sma11 proportion daily changes its form and composition and is moved to the 1and, where it can be used by man and from where it returns to the oceans. This process, which has no beginning and no end, is known as the hydrologic cycle. It comprises а gigantic system operating in and on the land and oceans of the earth and in the atmosphere surrounding it. It is estimated that something like 80,000 cubic miles of water are evaporated each year from the oceans, together with approximately 15,000 cubic miles of water evaporated from the lakes, rivers, canals and land surfaces of the continents. This total global evaporation is exactly balanced by the total precipitation. of which approximately 24,000 cubic miles in the form of waterfa11 on the land surfaces and the rest on the oceans. This cyclical movement of water is divisible into three main stages. Firstly, solar radiation, acting upon the surface of the oceans, heats the surface layers and causes evaporation and the diffusion of water vapour upwards into the atmosphere. The water vapour, which at this stage is pure, is then transported great distances by the winds. During its movement across the oceans and over the land, it may become polluted in а variety of ways: by atmospheric dust, by particles of radioactive material or by industrial and domestic smoke.
In the second stage of the cycle, the air masses containing the water vapour are suddenly cooled. This cooling, which may occur for а number of reasons, though primarily as а result of the air masses being forced to rise over high ground, causes condensation to take place and rain or snow to be precipitated. Of this precipitation, some falls directly into the oceans, out of man's reach and some is too heavily polluted.
The third and final stage is that in which the water moves back, over and under the 1and, into the oceans, from which it came. Of the water which falls upon the land, some flows оvег the surface, some sinks into the soil, and some is taken uр by the roots of vegetation to be used by plants and subsequently released into the atmosphere by transpiration. If, for example, an average of thirty inches of rainfa11 reaches the land surface each year, approximately twenty-one inches will evaporate directly or be transpired by vegetation. Of the remaining nine inches, most will run directly to the oceans as surface runoff or permeate the rock materials beneath the surface to form underground water аnd, at а later stage, indirectly reach the oceans. Water which began in the oceans sooner or later returns to them. The only stage in the cycle at which man can, at present, intervene and make use of the water on а large scale is the third, and only then if the water is comparatively pure.
Упражнения
1. Найдите в упражнении слова, сходные с русскими словами, переведите словосочетания на русский язык без использования словаря:
the total amount; minerals of our planet; hydrological cycle; solar radiation; diffusion of water; radio-active mаterial; industrial smoke; the stages of the cycle; atmospheric dust; global evaporation; final stage; gigantic system, to balance condensation; the ocean of air
II. Определите, к каким частям речи относятся следующие слова и переведите их:
1) to use, the use, used, usable; 2) to divide, division, divided, divisible; 3) to vary, variation, variable, invariable; 4) to move, movement, moved, movable; 5) to compare, comparison, compared, comparable; 6) to permeate, permeability, permeable; 7) to measure, measurement, measured, measurable
Ill. Выпишите парами слова-синонимы:
to take place, to return, to occur, to come back, tо cause, to comprise, to use, to make use of, to involve, to force, average, upwards, under, beneath, downward, part, upward, downwards, the rest, proportion, the remainder, quantity, mean, amount
IV. Найдите в тексте антонимы следующих слов:
to increase, little, pure, rarely, usable, approximately; to cool, condensation, to fall, initia1, to condensate, beginning, sooner, gradually
V. Из следующих предложений выпишите сказуемые-синонимы и определите их значения:
1. Solar radiation makes water evaporate from the surface of the ocean. 2. Solar radiation causes water to evaporate from the surface of the ocean. 3. Solar radiation forces water to evaporate from the ocean surface.
VI. Найдите в тексте слова, которые соответствуют следующим словарным определениям:
1)the total measurable supply of water of a11 forms of falling moisture; 2) total precipitation that appears in natural or artificial surface streams
Vll. Расположите следующие существительные в порядке, отражающем бесконечный гидрологический цикл:
runoff; precipitation; evaporation; infiltration and ground water; stream flow; reprecipitation
VIII. Переведите без словаря следующий текст и ответьте на вопрос: “Why is the knowledge of hydrology necessary for reclamation engineers?”.
Hydrology is science dealing with waters of the earth in rivers, streams, lakes, in or below the land surface, in the atmosphere in all its states – their occurrence, distribution аnd circulation through the unending hydrologic cycle of precipitation, consequent runoff, stream flow, infiltration and ground water, evaporation and reprecipitation. It is concerned with the physical, chemical and physiological reactions of the water with the rest of the earth and its relation to the life of the earth.
IX. Исходя из содержания текста, выберите для него наиболее подходящий заголовок:
"The Circulation of Water", "The Hydrological Cycle", "Sources of Water", "The Supply of Water".
Sources of Water
In practice, there are four genera1 sources of water available to man: surface water, ground water, atmospheric water and the oceans. The most important of these is surface water in the form of rivers, streams and lakes. Of the other three sources, ground water is increasing rapidly in importance, particularly in those areas which lack surface drainage. The use of pure water derived artificially from the atmosphere and the oceans may become significant if and when technological advances make it available on а sufficiently large scale and at an economic cost.
Ground water or, as it is sometimes called, underground water occurs below the surface of the ground in а zone of saturation, that is, the zone in which permeable rocks are saturated with water under hydrostatic pressure. Water moves down from the surface by gravity to enter this zone, the upper surface of which is called the water-table or phreatic surface; for this reason, ground water is sometimes called phreatic, subsurface or subterranean water. The lower 1irnit of the zone is the point at which the underlying rock formation becomes so dense that water cannot penetrate it. It may vary in depth from а few feet to hundreds of feet and there are isolated examples of porous rock having been found at depths of more than а mile. The zone of saturation is very important because it supplies all wells and maintains the normal, relatively uniform flow of streams. It acts as а gigantic reservoir which retains water during wet periods, causing а rise in the watertable.
Ground water has been laid down very unevenly beneath the surface and moves towards the oceans like surface water, only much more slowly.
The chief uses of ground water are for irrigation and domestic purposes. It is of no direct importance for the generation of hydroelectricity but of considerable indirect importance in that the flow of streams is primarily sustained by it.
Atmospheric water, or water vapour, has two major advantages over water contained in the oceans: it is to be found everywhere above the land surface and it is free of salt. Unfortunately, nо large-scale, successfu1, economic method has yet been devised to tap this water-supply and direct it to places where it is most needed. One serious initial obstacle lies in the fact that clouds are not necessarily water-bearing and may be 'dry'. If, however, they do contain appreciable amountsof water vapour, this may either dry out or condense and fall as rain or snow. The most that we have been able to do is to cause а particular humid cloud – one that would almost certainly sooner or later have precipitated – to shed its moisture at а time and place of our choosing.
This is achieved in one or two ways. The first method involves the "seeding" of clouds from aeroplanes or rockets with small particles of various chemicals, which cause waterdroplets to form and precipitation to take place. The second method is to create artificial convection currents by heating а large air mass near the ground. The air thereupon rises rapidly into the cloud, upsets the equilibrium, and causes precipitation. Some local successes have been achieved by these methods, but both are expensive and both depend upon the presence of water-filled clouds.
The oceans remain by far the largest potential source of water and together with the island seas contain 92.7 per cent of the earth's water. This water could be made potable if its saline content were reduced from about 35,000 parts per million to 500 parts per million or less. We have known for а long time that it is possib1e to produce fresh water by heating salt water and so promoting distillation.
Each of these processes depends upon the use of energy, which may be thermal, mechanical or solar. They each suffer from the disadvantage that the cost of desalination is very high.
It is clear therefore that although а great deal of water is available for use by man, the supply is not infinite. While it is likely that the quantity of usable water will be increased by desalination and the creation of artificial precipitation, it is certain that for some time to come the greater proportion of our water supply will be derived primari1y from surface runoff and to а lesser extent from subterranean sources.
Water is put to а great variety of uses: for irrigating crops, for the generation of hydroelectricity: for canals and waterways, for controlling pollution and as а source of food. All these uses are interdependent. For example, the construction of а modern dam promotes irrigation, the generation of hydroelectricity, flood control and recreation. Frequently, however, the uses of such natural resources as water may be mutually exclusive and а choice must sometimes be made between one, use and another.
Упражнения
I. Переведите следующие словосочетания исходя из сходства английских и русских слов:
hydrostatic pressure; the lower 1imit of the zone; rock formation; а wet period; hydroelectricity, successfu1 method; various chemicals; convection currents; loca1 success; potential source; salt water, the process of distillation; pollution control; а modern dam; isolated examples; in practice; equilibrium; uniform flow; thermal energy; gigantic reservoir
II. Определите, к каким частям речи относятся следующие слова и, переведите их:
significant, artificial, sufficient, successful, significantly, initially, sufficiently, successfully, artificially, initia1, particularly, particular, considerably, fortunate, appreciably, considerable, appreciable, fortunately
lll. Прочтите следующие предложения и скажите, отличаются лиони по содержанию:
1. The quantity of usable water is likely to be increased through desalinization and the creation of artificial precipitation. 2. It is likely that the amount of usab1e water wi1l be increased by means of desalinization and the creation of artificial precipitation. 3. The quantity of usable water is likely to be increased by desalinization and the creation of artificial precipitation. 4. The quantity of usable water is unlikely to be increased by means of desalinization and the creation of artificial precipitation
IV. Найдите в тексте предложения, в которых содержится:
1) отрицательная оценка метода опреснения морской воды;
2) описание работы по вызыванию искусственного дождя.
V. Сделайте пересказ текста “Sources of Water” °