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Ecosystem Cycles

Ecosystem Cycles

Author: John Lui
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Here is the link for the water cycle terms

Here is the link for the carbon cycle terms

Carbon Cycle

How could releasing this much pollution into the atmosphere not be a poor idea?

Burning of fossil fuels, such as oil and coal, releases carbon into the atmosphere in the form of carbon dioxide. This carbon must be cycled - removed from the atmosphere - back into living organisms, or it stays in the atmosphere. Increased carbon dioxide in the atmosphere contributes to the greenhouse effect on Earth.

The Carbon Cycle

Flowing water can slowly dissolve carbon in sedimentary rock. Most of this carbon ends up in the ocean. The deep ocean can store carbon for thousands of years or more. Sedimentary rock and the ocean are major reservoirs of stored carbon. Carbon is also stored for varying lengths of time in the atmosphere, in living organisms, and as fossil fuel deposits. These are all parts of the carbon cycle, which is shown in Figure below.

Carbon in the Atmosphere

Though carbon can be found in ocean water, rocks and sediment and other parts of the biosphere, the atmosphere may be the most recognizable reservoir of carbon. The most common form of carbon in the atmosphere is in the form of carbon dioxide CO2.

Carbon in Carbon Dioxide

Carbon cycles quickly between organisms and the atmosphere. In the atmosphere, carbon exists primarily as carbon dioxide (CO2). Carbon dioxide cycles through the atmosphere by several different processes, including those listed below.

Living organisms release carbon dioxide as a byproduct of cellular respiration.
Photosynthesis removes carbon dioxide from the atmosphere and uses it to make organic compounds.Carbon dioxide is given off when dead organisms and other organic materials decompose. 

Burning organic material, such as fossil fuels, releases carbon dioxide.
Carbon cycles far more slowly through geological processes such as sedimentation.

Carbon may be stored in sedimentary rock for millions of years.
When volcanoes erupt, they give off carbon dioxide that is stored in the mantle.
Carbon dioxide is released when limestone is heated during the production of cement.
Ocean water releases dissolved carbon dioxide into the atmosphere when water temperature rises.

Carbon dioxide is also removed when ocean water cools and dissolves more carbon dioxide from the air.

Because of human activities, there is more carbon dioxide in the atmosphere today than in the past hundreds of thousands of years. Burning fossil fuels and producing concrete has released great quantities of carbon dioxide into the atmosphere. Cutting forests and clearing land has also increased carbon dioxide into the atmosphere because these activities reduce the number of autotrophic organisms that use up carbon dioxide in photosynthesis. In addition, clearing often involves burning, which releases carbon dioxide that was previously stored in autotrophs.


Source: CK-12

Keeping up with the Carbon Cycle

Source: NASA

Water & Carbon Cycle

Source: CrashCourse Videos

Nitrogen & Phospahte Cycles

Source: CrashCourse Videos

Prezi on Cycles in Ecology

Source: Mr. Lui

Ecology Challenge

If you want a challenge try this quiz