The movement of mineral nutrients through organisms and their environment is called a ________ cycle.
Carbon is present in the atmosphere as ________.
- carbon dioxide
- carbonate ion
- carbon dust
- carbon monoxide
The majority of water found on Earth is:
- water vapor
- fresh water
- salt water
The average time a molecule spends in its reservoir is known as ________.
- residence time
- restriction time
- resilience time
- storage time
The process whereby oxygen is depleted by the growth of microorganisms due to excess nutrients in aquatic systems is called ________.
- dead zoning
The process whereby nitrogen is brought into organic molecules is called ________.
- nitrogen fixation
- nitrogen cycling
Which of the following approaches would be the most effective way to reduce greenhouse carbon dioxide?
- Increase waste deposition into the deep ocean.
- Plant more environmentally-suitable plants.
- Increase use of fuel sources that do not produce carbon dioxide as a by-product.
- Decrease livestock agriculture.
How would loss of fungi in a forest effect biogeochemical cycles in the area?
- Nitrogen could no longer be fixed into organic molecules.
- Phosphorus stores would be released for use by other organisms.
- Sulfur release from eroding rocks would cease.
- Carbon would accumulate in dead organic matter and waste.