The price tag put by researchers on the annual ecosystem services is about:
1. USD 11 trillion
2. USD 22 trillion
3. USD 33 trillion
4. USD 44 trillion
Identify the incorrectly matched pair:
Ecosystem service |
Cost out of total [%] |
|
1. |
Soil formation |
50 |
2. |
Nutrient cycling |
10 |
3. |
Climate regulation |
6 |
4. |
Habitat for wildlife |
3 |
The earth is regarded as “open” system with respect to:
1. | organisms | 2. | chemicals |
3. | energy | 4. | water |
If decomposers go extinct on Earth:
1. | Detritivores will replace them |
2. | Primary production will increase |
3. | Nutrients will accumulate in dead plants and animals |
4. | There will be no effect on carnivores |
A chemical that enters living organisms primarily from the atmosphere is:
1. | phosphorus | 2. | sulfur |
3. | sodium | 4. | carbon |
What is the best description of trophic efficiency?
1. | the ratio of net secondary production to the assimilation of primary production. |
2. | the percentage of production transferred from one trophic level to the next. |
3. | a measure of how nutrients are cycled from one trophic level to the next. |
4. | usually greater than production efficiencies. |
Nitrogen fixation is carried out by:
1. | bacteria | 2. | fungi |
3. | protists | 4. | algae |
What percent of the energy fixed by primary producers in a typical field ecosystem is received by a secondary consumer?
1. | 0.1% | 2. | 1% |
3. | 10% | 4. | 20% |
The rate at which energy is converted by photosynthetic and chemosynthetic autotrophs to organic substances is called as:
1. | biomass | 2. | transpiration |
3. | net primary productivity | 4. | gross primary productivity |
The chemical energy that is not converted to new biomass in the process of energy transfer between trophic levels in an ecosystem is finally:
1. removed in the feces
2. recycled by decomposers
3. used by heterotrophs to thermoregulate.
4. dissipated into space as heat