The role of Peatlands in the carbon cycle

Peatlands greatly aid control of the carbon content. It is important to know that despite covering a relatively small 3 percent of the earth’s total land surface, bogs hold a third of the total atmospheric carbon content. These regions are characterized by extensive plant cover, with the peat itself being an accumulated layer of organic material that has not undergone complete decomposition. This plant matter will have remained in the same location, in an environment that is oxygen deficient. This deficiency is as a result of the presence of a stable water level. The water can be either just below or just above the surface. Limited aerobic decomposition, therefore, is the key to the formation of peatlands.

Photosynthesis, emissions after the damage of the bogs, and the absorbed carbon in partially decomposed plant matter form are the primary processes that form the carbon cycle in peatlands. To correctly understand the aspects of each method, it is essential to look at the sub-processes that take place in these zones. Photosynthesis is a crucial part of the survival of plant life. It aids in the formation of food for the plant and is a vital part of the carbon cycle.

Carbon is the essential raw material that enables photosynthesis. This absorption of carbon as carbon dioxide is the critical process in the initial stages of photosynthesis. It is in the absorption of this compound that plants can generate organic compounds. During photosynthesis, a molecule of water is used up for every molecule of carbon dioxide absorbed.

The chemical equation of photosynthesis looks like this;

6C02 + 6H2O              In the presence of sunlight                        C6H12O6 + 6O2

 

Simplified, it means that six molecules of carbon dioxide react with six molecules of water – in the presence of sunlight – to produce a molecule of glucose and six molecules of oxygen. The glucose in this equation represents the energy that the plant needs to develop, generally referred to as ‘food’ in lay terms. The chief role of sunlight in the process is to provide the energy that facilitates the reaction. Oxygen is a crucial byproduct of this process.

A closer examination of the process makes it evident that the healthier the peatland, the more significant the number of plants, and the higher its capacity to absorb carbon.

The principal way in which peatlands absorb carbon is the presence of a low oxygen level. Low levels of oxygen, in turn, hamper the decomposition process. The stagnation of this process, therefore, means that the carbon content in the dead plant fails to be oxidized. This halting of the process means that there is no conversion to carbon dioxide that eventually ends up in the atmosphere. Human activity has overseen the draining of an estimated 65 million hectares of peat bogs. In the drying process after the peatland drainage, microbes subsequently find the perfect combination of carbon (food) and oxygen. This environment is ideal for the formational of additional CO2. The extra carbon dioxide forms other emissions into the atmosphere. The decay or draining of peatlands alone is responsible for the release of approximately three billion tons of carbon dioxide into the atmosphere annually.

Another activity that has proven harmful is burning of peat bogs. This process directly releases carbon back into the atmosphere as well as reducing the capacity of the peatland to absorb and keep carbon levels in check. Peatlands hold an estimated 500 billion metric tons of carbon, exceeding the ability of all the world’s forests combined. This total amounts to about 1,450 metric tons contained in each hectare of peatland. They can hold carbon for even thousands of years. To control the carbon content, protection of peat bogs is crucial.