Home Link to Earth Structure Link to Biosphere Link to Atmosphere Link to Hydrosphere Link to Biogeochemical Cycles Link to Activities Geography4Kids Sections Search
Biogeochemical Cycles of the Earth

Yes. Iron Cycles Too.

Iron (Fe) atoms also cycle through the ecosystems of the world. Although there is cross-over, there is a difference between the cycling on land and in the water. The differences are based on how the producers get their iron in the first place. Iron must be in the seawater for sea plants and phytoplankton to use it. A great deal of iron is in the soil or other organisms for the land creatures to consume.

Start With The Plants

As with many cycles, the iron cycle starts with plants. Plants on land get their iron from the soil. Iron is an abundant element on the planet so you will find it in many rocks and biomes. Good soils are often rich in iron compounds. Iron also gets into the soil when organisms die and sometimes when they poop. All organisms use iron in some form. Iron is an essential nutrient. Many enzymes require iron to work. So plants get iron out of the soil and into their tissues.

Then The Animals

Animals need plants to get iron into their systems. You might get iron by eating beets, carrots, celery, or potatoes. If you eat meat you will get a lot of iron from eating the flesh of other animals. The main point is that animals need to eat substances that have already absorbed iron. We can't get our iron from the soil or by eating rocks. Humans use iron in their hemoglobin. Hemoglobin is the compound that carries oxygen through the body. A lack of iron in the diet results in a disease called anemia.

Iron Does An Organism Good

Once the iron is captured from the environment it is free to circulate between plants and animals. Scientists have even tried to stimulate the growth of plants in the ocean by adding iron to the water. The phytoplankton grew more with the extra iron, but it was only a temporary effect. Iron usually makes its way into the ocean from runoff or from the dust circling the earth. When a volcano erupts, large amounts of dust are sent into the atmosphere. That iron rich dust lands on the soil and in the ocean.

Next Stop On Geography4Kids Tour
Next page on the biogeochemical cycles.
- Overview
- Energy
- Carbon
- Water
- Oxygen
- Nitrogen
> Iron
- Phosphorus
- Rocks


Link to Link to Link to Link to Link to Link to Rader Network Side Navigation

Study of Antarctica Rocks (US-NSF Video)
- or -

Earth Science Quiz

Biogechemical Cycles Quiz

Useful Reference Materials (Iron Cycle):
Encyclopædia Britannica (Iron):

- Geography4Kids: Phosphorus Cycle
- Chem4Kids: Biochemistry
- Chem4Kids: Chemical Reactions
- Chem4Kids: Environmental Chemistry
- Biology4Kids: Passive Transport
- Biology4Kids: Digestive System
- Biology4Kids: Respiratory System
- Biology4Kids: Plants
- Cosmos4Kids: Earth

- NASA: Kennedy Space Center
- NASA: Goddard Spaceflight Center

Search for more information...

* The custom search only looks at Rader's sites.

Help Page Go for site help or a list of earth science and geography topics at the site map!
©copyright 1997-2015 Andrew Rader Studios, All rights reserved.
Current Page: | Physical Geography | BGC Cycles | Iron Cycle

** Andrew Rader Studios does not monitor or review the content available at these web sites. They are paid advertisements and neither partners nor recommended web sites.