G8_The Story of Coal and the Carbon Cycle_Gradelevel_03
He explained, that typically, plants take in carbon dioxide from the atmosphere and release oxygen. You can imagine large areas of dense forest would be taking in a lot of carbon as the trees grow. This action is just one of the many critical components in the carbon cycle. It is this process that moves carbon from the atmosphere to the biosphere.
Typically, when vegetation dies, the decay process begins almost immediately. This decay process breaks down the vegetation into simpler organic matter thereby releasing the locked-up carbon. This process is called decomposition. In these low-lying swampy areas of the coal forests, the water is still and contains very little oxygen. This stagnant water thereby slows any decay process for any plant matter falling into the water. Over time, the natural processes of sedimentation covers the dead plant matter that has fallen into the shallow oxygen-depleted waters. As more and more sediments were deposited over the vegetation, the vegetation is compressed.
This action provides more protection from natural decay. In a coal forest, this process of decay is bypassed. This bypassing enables the carbon content of the vegetation to stay intact, in this case, for over 300 million years. Without this unique environment, the carbon would have been quickly recycled back into the environment as a natural part of the carbon cycle.
The guide further explained of how coal is formed from the plant matter. He discussed how, as time passed, the organic sediment was covered with more and more soil. Thusly, it became deeply burying it under the layers of sediment. Once the temperature and pressure reached a high enough level, the “coalification process” begins.
Coalification is a chemical process where water, methane and carbon dioxide are pushed out leaving behind a rich concentration of carbon. Coals is ranked according to the proportion of carbon it contains.