Вопрос № 1054922 - Экология

When examining the soil of the potato field the quantity of rain worms was calculated on test plots 100*100 centimeters in size. In 10 test plots there were found 120 rain worms. To combat potato beetle the field was pesticide-laden and then the rain-worm were recalculated in the same test plots. There were only 30 rain worms found. Calculate the population density of rain worms per square meter before and after pesticide-laden; calculate by how many times the population density has become lower under the impact of pesticide. (Give your answers in the answer fields as whole numbers separated by a comma without any spaces.)

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Вопрос задал(а): Анонимный пользователь, 13 Ноябрь 2020 в 18:02
На вопрос ответил(а): Анастасия Степанова, 13 Ноябрь 2020 в 18:02

Вопрос № 222833

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Scientists are finding other effects of acid rain. In some large areas trees are dying. Not just one tree here and there, but whole forests. At first scientists couldn’t understand why. There were no bugs or diseases in these trees. The weather was not dry. But now they think that the rain was the cause. Acid rain is making the earth more acidic in these areas. Some kinds of trees cannot live in the soil that is very acidic.

The Weather

Forests

Acid Rain

Effects of Acid Rain

Вопрос № 1054928

Decrease of the ozone layer by 1 % leads to increase in the steam of ultraviolet light by 2 % and increases the skin cancer occurrence by 4%. Calculate the reduction of the ozone layer (%), increase of the ultraviolet light (%) and increase of skin cancer (%) by 2063 in relation to the present time on condition that the average ozone layer annual thinning rate is by 0,2%. (Give your answer in the field for answers as whole numbers separated by a comma.)

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