Carbon compounds global estimates

The efficiency of the carbon sink on land depends on the transformation of carbon compounds into forms characterized by having a long lifetime (wood, soil). An enhancement of carbon sink due to increasing NPP can manifest itself only as a result of the inertia of these slow reservoirs of carbon in the process of land cultivation. At present, global pure production in agriculture is estimated at 8 109 tCyr-1. 

Carbon. Most of the Earth s supply of carbon is stored in carbonate rocks in the Hthosphere. Normally the circulation rate for Hthospheric carbon is slow compared with that of carbon between the atmosphere and biosphere. The carbon cycle has received much attention in recent years as a result of research into the possible relation between increased atmospheric carbon dioxide concentration, most of which is produced by combustion of fossil fuel, and the "greenhouse effect," or global warming. Extensive research has been done on the rate at which carbon dioxide might be converted to cellulose and other photosyntheticaHy produced organic compounds by various forms of natural and cultivated plants. Estimates also have been made of the rate at which carbon dioxide is released to soil under optimum conditions by various kinds of plant cover, such as temperature-zone deciduous forests, cultivated farm crops, prairie grassland, and desert vegetation. 

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