Carbon river fluxes

Probst, J.L., Mortatti, J., and Tardy, Y. (1994) Carbon river fluxes and weathering CO2 consumption in the Congo and Amazon river basins. Appl. Geochem. 9, 1-13. 

The quantity of primary production that is exported from the upper ocean is said to be equivalent to new production (18, 19) New primary production is that associated with allocthonous nutrients (i.e., those upwelled or mixed into the euphotic zone or input via rivers and rain). In order for steady state to be maintained, an equivalent flux out of the euphotic zone is required. Earlier studies (19) suggested that sediment-trap measurements of particulate organic carbon (POC) flux were equivalent to new primary production however, recently it has become clear that these measurements probably represent only a... 

Fluss-bett, n. river bed. -bild, n. flow sheet, -dichte,/. flux density, -eisen, n. mild (soft, low-carbon) steel, ingot steel, -erde, /. earthy fluorite, -gebiet, n. river basin, -gold, n. river gold, -harz, n. anim, gum anim. ... 

The magnitude and fate of coastal-zone biological production is a major unknown in the global carbon cycle. Since river nutrient flux into these regions may be altered with C02-induced climate change, it is important that generation and fate of coastal-zone production be better understood. 

Rainwater and snowmelt water are primary factors determining the very nature of the terrestrial carbon cycle, with photosynthesis acting as the primary exchange mechanism from the atmosphere. Bicarbonate is the most prevalent ion in natural surface waters (rivers and lakes), which are extremely important in the carbon cycle, accoxmting for 90% of the carbon flux between the land surface and oceans (Holmen, Chapter 11). In addition, bicarbonate is a major component of soil water and a contributor to its natural acid-base balance. The carbonate equilibrium controls the pH of most natural waters, and high concentrations of bicarbonate provide a pH buffer in many systems. Other acid-base reactions (discussed in Chapter 16), particularly in the atmosphere, also influence pH (in both natural and polluted systems) but are generally less important than the carbonate system on a global basis. 

Keywords Carbonate dissolution, Dissolved flux, Dissolved load, Ebro River basin, Evaporite dissolution, Long-term fluxes... 

Tipper ET, Bickle MJ, Galy A, West AJ, PomiFs C, Chapman HJ (2006) The short term climatic sensitivity of carbonate and silicate weathering fluxes insight from seasonal variations in river chemistry. Geochim Cosmochim Acta 70(ll) 2737-2754... 

The latter two assumptions are simplistic, considering the number of factors that affect pH and oxidation state in the oceans (e.g., Sillen, 1967 Holland, 1978 McDuff and Morel, 1980). Consumption and production of CO2 and O2 by plant and animal life, reactions among silicate minerals, dissolution and precipitation of carbonate minerals, solute fluxes from rivers, and reaction between convecting seawater and oceanic crust all affect these variables. Nonetheless, it will be interesting to compare the results of this simple calculation to observation. 

If 0.24 Pg C/a represents riverine DIC delivered to oceans (Meybeck 1993) and if the flux of carbon from rivers/lakes to the atmosphere is 20% (Kling et al. 1991) of the total (i.e., 0.12 Pg C/a), then 0.23 Pg C/a remains in inland lakes and rivers, and in slowly cycled groundwater. Cole et al. (2007) estimated that about 0.2 Pg C/a is buried in inland water sediments. Groundwater may have a greater carbon storage capacity due to its large volume and greater load of carbon than rivers (Kempe 1984). 

Raymond, P.A. Oh, N.H. et al. 2008. Anthropogenically enhanced fluxes of water and carbon from the Mississippi River. Nature, 451, 449-452. 

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