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Task 2. Match the words and word combinations to their definitions




1. Consumptive a. a balance between two opposing things, that you are willing to accept in order to achieve something
2. Available b. the process of supplying lands and crops with water
3. Sewage c. chiefly derogatory of or relating to the using up of resources
4. Irrigation d. to improve something
5. Crop e. something that is present and is able to be used
6. Enhance (v) f. the mixture of waste from the human body and used water that is carried away from houses by pipes under the ground
7. Trade-off g. a piece of equipment used for scattering water on grass or soil
8. Furrow h. the amount of wheat, rice, fruit etc. that is produced in a season
9. Sprinkler i. a wide deep line made in the surface of the ground

Task 3. Read the text and translate the second paragraph in written form

The use of fresh water in agriculture

Uses of fresh water can be categorized as consumptive and non-consumptive (sometimes called renewable). A use of water is consumptive is that water is not immediately available for another use. Losses to sub-surface seepage and evaporation are considered consumptive, as is water incorporated into a product (such as farm produce). Water can be treated and returned as surface water, such as sewage, is generally considered non-consumptive if that water can be put to some additional use.

It is estimated that 69% of worldwide water use is for irrigation, with 15-35% of irrigation withdrawals being unsustainable.

In some areas of the world irrigation is necessary to grow any crop at all, in other areas it permits more profitable crops to be grown or enhances crop yield. Various irrigation methods involve different trade-offs between crop yield, water consumption and capital cost of equipment and structures. Irrigation methods such as furrow and overhead sprinkler irrigation are usually less expensive but are also typically less efficient, because much of the water evaporates, runs off or drains below the root zone. Other irrigation methods are considered to be more efficient and include drip or trickle irrigation, surge irrigation, and some types of sprinkler systems where the sprinklers are operated near the ground level. These types of systems, while more expensive, usually offer greater potential to minimize runoff, drainage and evaporation. Any system that is improperly managed can be wasteful, all methods have the potential for high efficiencies under suitable conditions, appropriate irrigation timing and management. One issue that is often insufficiently considered is salinization of sub-surface water.

Aquaculture is a small but growing agricultural use of water. Freshwater commercial fisheries may also be considered as agricultural uses of water, but have generally been assigned a lower priority than irrigation.

As the global population grows and the demand for food increases in the world with a fixed water supply, there are efforts underway to learn how to produce more food with less water, through the improvements in irrigation methods and technologies, agricultural water management, crop types and water monitoring.

Task 4. Decide whether the following statements are True (t) or False (F). If you think the statement is false, change it to make it true

1. Consumptive water use means that water is immediately available for any use.

2. More than half of worldwide water use is used for irrigation.

3. Among the most efficient methods of irrigation are furrow and overhead sprinkler irrigation.

4. Drip or trickle irrigation and surge irrigation are efficient and inexpensive.

5. Aquaculture can be viewed as another kind of water use.

6. Improvements in irrigation methods is one more way to produce more food for the growing world population.

 





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