Processes of the Long-Term Carbon Cycle: Organic Matter and Carbonate Burial and Weathering

The organic subcycle of the long-term carbon cycle, where organic matter burial and weathering are involved, constitutes the major control on the evolution of atmospheric oxygen. It is also important as a secondary factor affecting atmospheric CO2. Thus, it is important to better understand the processes whereby organic matter is buried in sediments and oxidized upon subsequent exposure to weathering during uplift onto the continents. This is especially true of the Paleozoic rise of land plants, which had a large effect on atmospheric CO2 because of increased global organic burial due to the addition of plant debris to sediments. The burial of organic matter in marine sediments is impacted strongly by the availability of the nutrient elements, phosphorus and nitrogen, so a complete discussion of the cycling of organic carbon should involve some discussion of the cycles of these elements.

Carbonate burial is the ultimate sink for CO2 derived from the atmosphere via the weathering of Ca and Mg silicates. The location of this burial, shallow water shelves versus the deep sea floor, is important because it affects the probability that the carbonate will be eventually thermally recycled and the carbon returned to the atmosphere. Carbonate weathering is the dominant process affecting river water composition and is a key component of the cycling of carbon. Its importance to the long-term carbon cycle is that, in order to calculate the removal of CO2 from the atmosphere via Ca and Mg silicate weathering, it is neces sary to correct total carbonate burial for that derived from carbonate weathering.

Organic Gardening

Organic Gardening

Gardening is also a great way to provide healthy food for you and your loved ones. When you buy produce from the store, it just isnt the same as presenting a salad to your family that came exclusively from your garden worked by your own two hands.

Get My Free Ebook

Post a comment