Key in the ecosystem figures

Exercise and reference answers

Questions

1. Answer

   10

   Question

   Percentage of energy that passes from one trophic level to the next

2. Answer

   170

   Question

   Annual net primary productivity of the whole biosphere, in billion tons

3. Answer

   55

   Question

   Yearly productivity of the oceans, in billion tons

4. Answer

   70

   Question

   Percentage of the Earth's surface the oceans occupy

Instructions

Read each prompt and key the number in on the pad.

Explanation