Carbon cycle, inorganic

Fig. 2.9 Scheme of the inorganic carbon cycle (inorganic carbon burial). 

Fig. 11-9 (a) The vertical distributions of alkalinity (Aik) and dissolved inorganic carbon (DIC) in the world oceans. Ocean regions shown are the North Atlantic (NA), South Atlantic (SA), Antarctic (AA), South Indian (SI), North Indian (NI), South Pacific (SP), and North Pacific (NP) oceans. (Modified with permission from T. Takahashi et ah, The alkalinity and total carbon dioxide concentration in the world oceans, in B. Bolin (1981). Carbon Cycle Modelling," pp. 276-277, John Wiley, Chichester.)... 

The strong increase in atmospheric concentrations of carbon dioxide [ 127] has generated considerable interest in the global carbon cycle [ 128-130]. Techniques for determining the components of the carbonate system have been refined, new techniques have been developed, or both. Among the four measurable parameters (total inorganic carbon), pH, pC02, and total alkalinity... 

The oceanic carbon inventory was presented in Table 15.3. Most of the carbon is inorganic (98%), predominantly in the form of bicarbonate (87%), and is located in the intermediate and deep waters. Of the 2% that is organic, the majority is DOC (see Table 23.2). At present, the ocean is acting as a net sink for atmospheric CO2. In the modern-day carbon cycle, the sole oceanic sink fitr carbon is burial in the sediments in the form of detrital biogenic PIC and POC. 

Miller, W. L., and R. G. Zepp. 1995. Photochemical production of dissolved inorganic carbon from terrestrial organic matter Significance to the oceanic organic carbon cycle. Geophysical Research Letters 22 417-420. 

To begin the discussion, we will present briefly a view of the modern carbon cycle, with emphasis on processes, fluxes, reservoirs, and the "CO2 problem". In Chapter 4 we introduced this "problem" here it is developed further. We will then investigate the rock cycle and the sedimentary cycles of those elements most intimately involved with carbon. Weathering processes and source minerals, basalt-seawater reactions, and present-day sinks and oceanic balances of Ca, Mg, and C will be emphasized. The modern cycles of organic carbon, phosphorus, nitrogen, sulfur, and strontium are presented, and in Chapter 10 linked to those of Ca, Mg, and inorganic C. In conclusion in Chapter 10, aspects of the historical geochemistry of the carbon cycle are discussed, and tied to the evolution of Earth s surface environment. 

Figure 10.12 illustrates the carbon and sulfur isotopic compositions of a variety of materials. For both carbon and sulfur, there is an important fractionation that obtains when organic processes are involved. Organic material is depleted in 3c, and sulfide produced from bacterial reduction of sulfate is depleted in 34s. In the exogenic carbon cycle, there are two principal reservoirs of carbon the oxidized inorganic carbon reservoir, which is mostly carbonate... 

There is a strong need both from a scientific and practical viewpoint for a more quantitative understanding of the inorganic and organic carbon cycles and their interactions immediately prior to important human intervention in these cycles. 

Mineralisation Conversion of a biodegradable plastic to C02, H20, inorganic compounds and biomass. For instance the carbon atoms in a biodegradable plastic are transformed to C02, which can then reenter the global carbon cycle. 

The natural rates of carbon cycling in oceans and land are nearly in a steady state that is, the rates of movement of carbon between the atmosphere and trees, or between algae and the inorganic carbon dissolved in the ocean do not change measurably from year to year and tend to balance each other. However, human activities have recently introduced changes that will be addressed in Chapter 8. 

Mechanistic Modeling of the Organic and Inorganic Carbon Cycle in Soils... 

Aravena R., Schiff S. L., Tmmbore S. E., Dillon P. J., and Elgood R. (1992) Evaluating dissolved inorganic carbon cycling in a forested lake watershed using carbon isotopes. Radiocarbon 34(3), 636—645. 

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