Текста. Перепишите и письменно переведите 1, 3 и 4-й абзацы.

The plague that's killing trees

1. A strange sickness influences the growth of tree throughout vast areas of American forests. Scientists fear it being the start of a widespread environmental disaster. From mountain peaks of New England to foothills in the Deep South, some species of trees p.re being deformed and some have stopped growing at all. The trees are losing their vitality and resistance to insects and di­seases. Beech trees are producing abnormally brittle wood (xpyпкая древесина). Spruce and fir branches are growing vertically instead of horizontally. Acid rain and air pollution are supposed to be the causes of such disaster. Acidity breaks down the waxy coating on leaves. Roots are damaged. The loss of green color (chlorosis) points to nutrient deficiency in the soil.

2. Scientists agree that when coal, oil and other fuels are burnt, the emissions are converted in the atmosphere into particles that return to the earth in the form of highly acidic rain (кислотный дождь), snow or fog. There is certainly a close link between acid rain and the devastation (paзорение) of forests. Gaseous pollu­tants such as nitrogen oxides, sulfur dioxide and airborne mic­roscopic particles of metals pollute the atmosphere and influence the plant growth.

3. It was estimated that biomass — the combined weight of tree trunk, limbs and branches — in Vermont dropped for eight spe­cies of trees. The most dramatic change is in the red spruce (aмериканская ель). More alarming is the 25% decline in bio­mass of the commercially valuable sugar maples and beeches. Commercial foresters report no change in timber production.

4. But scientists are discovering shortages to come in many areas. Timber economy is growing slower than ever. Pitch-pine growth is already at a standstill, hardwoods (древесина твердых пород), such as: yellow birch, black oak, sugar maple and hickory (гикори - сорт дерева) are also affected. Even tolerant trees are losing growth. According to the results of an Oak Rid­ge National Laboratory study of 34 species in 15 states in the eastern half of the nation hidden damage is occuring.

II Прочтите 2 -ой абзац текста и письменно ответьте на следующий вопрос:

What pollutes the atmosphere and influences the plant growth?

Контрольная работа № 5

(для специальностей ЛХФ)

Вариант 5

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