The Written Test

Instructions for the contestant

This test consists of 6 themes. Each theme contains a number of questions. The number of marks you can gain for a correct answer is given for each question. The maximum number of marks is 100. Do not give more answers (reasons, examples, etcetera) than is requested. For example, if two reasons are asked and you give more than two reasons, only the first two are taken into account. Any question that calls for an explanation or a commentary will only gain marks if the answer contains such explanation or comment. Write all the answers with the corresponding numbers on your answering sheet. Use a new answering sheet for each theme. You have three hours to complete this test.

Good luck!

Theme C: The water cycle

Location: Lake Aral

Study the maps of the subsiding lake Aral in source C.2. and the graphs in source C.1.

17. Because of what human activity has lake Aral subsided? (2 marks)

18. Mention two causes of the rising salt content of lake Aral. (2 marks)

19. About 20 of the 24 species of fish in lake Aral have disappeared. Fishing, which amounted to 44,000 tons in the fifties and which provided about 60,000 jobs, has gone down to zero. Make a connection between these facts and the subsidence of lake Aral. (2 marks)

20. The climate round lake Aral has changed. Summers have yielded higher temperatures, winters have become colder. Because frost appears earlier and remains longer, the growth season has become shorter. Find a connection between the changes in the climate and the subsidence of lake Aral. (3 marks)

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