2.5. Read the text.

1. On the basis of word-building chains with the stem “moist” and “drip” try to define:

– the factors which provide a soil-water-plant relationship and favour better growth and better yields;

– the peculiarities of the trickle irrigation on shallow rooted crops, on crops like vines and bananas, in the case of fruit trees and so on.

2.6. Translate the text into Ukrainian: text a.

1. Drip or trickle irrigation can be defined as the continuous maintenance of adequate portion of the root zone of a plant with moisture somewhere between saturation and field capacity during the entire growing season. This provides a soil-water-plant relationship that favours better growth and better yields because the plant is never subjected to moisture stress.

2. Work on the drip irrigation has been gaining acceptance in Australia, United States and other parts of the world since the 1980s. In the United States the greatest interest in drip irrigation is presently in California and the south-west where the relatively low water requirements are very attractive.

3. Overall water use is considerably reduced by eliminating evaporative losses during application and supplying only the plants` exact requirements. In this way, water sources normally considered too small for irrigation may be used.

4. The basic components of the drip irrigation system are head-unit, including control valves, water-meter, pressure gauge, fertilizer tank and injector, main pipe of 1,5 or 2 in diameter, laterals of 0,5 in diameter which are inserted into the main pipe at intervals.

5. On shallow rooted crops such as vegetables on light (sandy) soils, the drippers spacing is 24 in apart. On fairly heavy soils this may be increased to 40 in apart. On crops like vines and bananas, drippers are usually spaced 40 in apart but this may be increased to 50 in on heavy soils.

6. In the case of fruit trees, the usual dripper spacing is 50 in apart but on old trees, having a shallow and wide-spread root system and growing on light sandy soils, two rows of drippers per row of trees are sometimes used in such cases, drippers are spaced 60 in apart along the line.

7. Generally it can be said that the shallower the root system and the more sandy the soil, the closer the dripper spacing will be. The small bore of the micro-tube restricts the rate at which water can leave the lateral, but the degree of restriction depends on the length of the micro-tube.

8. According to the reports from the farmers who have been using the trickling lines for the past twenty years the system has the following potential advantages:

a) increased yields;

b) accelerated growth of young trees and plants;

c) root zone remains moist all the time;

d) plant is not subject to continual cycles of soil saturation to wilting point and the consequent set-backs to growth.

9. Besides, water and fertilizers can be applied at the same time and there is a significant water conservation. Area between rows remains firm and dry assisting in spraying and harvesting operations. And as for the use of poor quality water – high saline waters have been used with far less damage that comparable waters used with sprinklers.

10. People who have been working with this system since the early eighties are optimistic that there will not be as many disadvantages in all the soil types as there are advantages. However, there are some areas, which need further investigation.