4.3. Ask your groupmates questions in English about:

– у яких країнах метод крапельного зрошення отримав визнання;

– яка структура системи крапельного зрошення;

– які особливості розташування крапельниць при зрошенні різних с/г культур;

– які шляхи розв’язання невирішених проблем крапельного зрошення.

4.4. Fill in the gaps from the words given below:

1. In trickle irrigation pressures and flow rates are much…. those used in conventional irrigation systems.

2. Water and … can be applied at the same time and there is an important water conservation.

3. … normally considered too small for drip irrigation may be used.

4. On fairly … the drippers spacing may be increased.

5. Area between rows remains firm and dry assisting in spraying and…

(heavy soils, fertilizers, harvesting operations, below, water sources).

4.5. Get ready to speak on the following topics (3-5 sentences):

1. The general characteristics of drip irrigation.

2. The advantages of trickle irrigation.

3. The basic components of the trip irrigation system.

4. A relatively new method of irrigation and perspectives of its application.

4.6. Write a summary of Text a in English.

4.7. Pair-work. Role-play. You are a professor. You are examining one of your students. Ask him questions concerning the advantages and disadvantages of trickle irrigation.

V. Additional text

5.1. Memorize the following words:

community	суспільство
waterway	водний шлях
wastes	відходи
to contaminate	забруднювати, заражати
to affect	діяти, впливати
depletion	вичерпування (запасів, ресурсів), спустошення
scope	сфера, обхват, розмах
to consume	споживати
to decrease	зменшувати, спадати
fitness	придатність
inadmissible	недопустимий, неприйнятний
to shift	переміщати, зсовувати
a closed production cycle	замкнутий цикл виробництва
there is no doubt	безсумнівно
to acquire a growing importance	набувати все більшого значення
a means of treatment	засіб очищення
to claim	вимагати
sewage	стічні води
arid areas	засушливі землі
hardy crops	стійкі, витривалі культури
low-salinity sea water	морська вода з низьким вмістом солей
to dump	викидати, скидати
meanwhile	тим часом, в той же час

5.2. Read the text. Text b. Protection of water.

1. Ever since man progressed from a hunting to an agricultural society, with the corresponding development of stable communities, the phenomenon of water pollution has been his constant companion.

2. The hydrosphere is a dynamic system containing physico-chemical and biological equilibria, and there is no doubt that a normally active waterway has a large capacity to assimilate wastes.

3. However, in many areas this capacity is now being reached or exceeded so that many waterways are becoming increasingly contaminated. Before this contamination becomes readily noticeable, however, equilibria are changed and the ecological structure may be seriously affected.

4. The question of the rational use of water resources and their protection from pollution is acquiring growing importance in Ukraine. The Law on Conservation of Nature states that all rivers, lakes and underground waters are to be protected from depletion and pollution as water supply resources, a source of energy and means of treatment.

5. It is obvious that the exploitation of water resources is extremely varied at the present time. The scope of water resource exploitation is growing rapidly due to population growth, fast development of industry and expansion of irrigated land areas.

6. Unlike other natural resources water renews itself. This is due to its constant circulation in the ocean-atmosphere-earth-ocean system. No matter how much water is consumed in daily industrial life, its amount does not decrease. With time and under certain conditions water regains its properties and its fitness for drinking. This is probably the reason why resources a long time appeared to be unlimited.

7. However, this view has substantially changed in the past 40 or 50 years. The use of water leaves it polluted. Newspapers report that all the large rivers of industrially developed countries are completely or partially polluted. So it is absolutely inadmissible to dump uncleaned sewage into rivers and lakes.

8. The most effective method of protecting the water environment is to shift to a closed production cycle. Today water recycling in industrial enterprises is a reality. In Ukraine recirculated water systems have been functioning in many plants and factories since the 1980s.

9. Worldwide, the irrigation claims almost 80 per cent of the water consumption. Meanwhile stable crops can also be obtained in other equally effective ways – by employing agricultural practice designed specially for arid areas and by choosing the most hardy crops and their varieties.

10. An interesting experience is that of some farms in the southern regions of Ukraine which have introduced irrigation by low-salinity sea water.