Nitrogen biogeochemical cycle

B. H. SvENSSON and R. Soderlund (eds.). Nitrogen, Phosphorus, and Sulfur-Global Biogeochemical Cycles, SCOPE Report, No. 7, Sweden 1976, 170 pp. also SCOPE Report No. 10, Wiley, New York, 1977, 220 pp, and SCOPE Newsletter 47, Jan. 1995, pp. 1-4. 

Feedbacks may be affected directly by atmospheric CO2, as in the case of possible CO2 fertilization of terrestrial production, or indirectly through the effects of atmospheric CO2 on climate. Furthermore, feedbacks between the carbon cycle and other anthropogenically altered biogeochemical cycles (e.g., nitrogen, phosphorus, and sulfur) may affect atmospheric CO2. If the creation or alteration of feedbacks have strong effects on the magnitudes of carbon cycle fluxes, then projections, made without consideration of these feedbacks and their potential for changing carbon cycle processes, will produce incorrect estimates of future concentrations of atmospheric CO2. 

It is often taken for granted that the oxygen content of the air is nearly constant at ca. 20% of the atmospheric volume, that most of the liquid water on the planet is aerobic (i.e. contains O2), and that most water has pH values relatively close to neutral" (close to 7). However, these circumstances are not mere coincidences but are in fact consequences of the interaction of key global biogeochemical cycles. For instance, the pH of rainwater is often determined by the relative amounts of ammonia and sulfuric acid cycled through the atmosphere, a clear example of interaction between the nitrogen and sulfur cycles. 

Just as in the case for the hydrosphere, the atmosphere participates in all of the major biogeochemical cycles (except for phosphorus). In turn, the chemical composition of the atmosphere dictates its physical and optical properties, the latter being of great importance for the heat balance of Earth and its climate. Both major constituents (O2, H2O) and minor ones (CO2, sulfur, nitrogen, and other carbon compounds) are involved in mediating the amounts and characteristics of both incoming solar and outgoing infrared radiation. 

Reproduced with permission from R. J. Charlson, W. L. Chameides, and D. Kley (1985). The transformations of sulfur and nitrogen in the remote atmosphere. In "The Biogeochemical Cycling of Sulfur and Nitrogen in the Remote Atmosphere" (J. N. Galloway, R. J. Charlson, M. O. Andreae and H. Rodhe, eds), pp. 67-80, D. Reidel Publishing Company, Dordrecht.)... 

Christensen J. P., Murray, J. W., Devol, A. H. and Codispoti, L. A. (1987). Denitrification in continental shelf sediments has major impact on oceanic nitrogen cycle. Glob. Biogeochem. Cycles 1,97-116. 

Gruber, N. and Sarmiento, J. L. (1997). Global patterns of marine nitrogen fixation and denitrification. Glob. Biogeochem. Cycles 11,235-266. 

Karl, D., Letelier, R., Tupas, L. et al. (1997). The role of nitrogen fixation in biogeochemical cycling in the subtropical North Pacific Ocean. Nature 388, 533-538. 

C. J. and Schloss, A. L. (1997). Equilibrium responses of global net primary production and carbon storage to doubled atmospheric carbon dioxide Sensitivity to changes in vegetation nitrogen concentration, Global Biogeochem. Cycles 11,173-189. 

Schimel, D. S., Braswell, B. H., McKeown, R., Ojima, D. S., Parton, W. J. and Pulliam, W. (1996). Climate and nitrogen controls on the geography and time-scales of terrestrial biogeochemical cycling. Global Biogeochem. Cycles 10, 677-692. 

Fig. 12-2 Partitioning of the various forms of nitrogen in the atmosphere. Units are Tg N. (Reprinted with permission from R. Soderlund and T. Rosswall, The nitrogen cycles. In O. Huntizger (1982). "The Natural Environment and the Biogeochemical Cycles," p. 70, Springer-Verlag, Heidelberg.)...

Galloway J. N. et al. (1995). Nitrogen fixation Anthropogenic enhancement - environmental response. Global Biogeochem. Cycles 9,235-252. 

Jaffe, D. A. (1992). The nitrogen cycle in global biogeochemical cycles. In "Global Biogeochemical Cycles" (S. S. Butcher, R. J. Charlson, G. H. Orians, G. V. Wolfe, eds). Academic Press, New York. 

Schindler, D. W. and Bayley, S. E. (1993). The biosphere as an increasing sink for atmospheric carbon Estimates from increased nitrogen deposition. Global Biogeochem. Cycles 7,717-733. 

Fig. 6.5 Microbial iron and sulfur cycles that may have dominated biogeochemical cycling before the origin of oxygenic photosynthesis, aerobic respiration and possibly before the use of oxides of nitrogen.

Effects of wastewater treatment plant discharge on the ecology of bacterial communities in the sediment of a small, low-gradient stream in South Australia, and the quantification of genes involved in the biogeochemical cycling of carbon and nitrogen [167]... 

Since nitrogen is a nutrient, which limits the productivity of almost all Boreal and Sub-Boreal Forest ecosystems, its biogeochemical cycling is relatively well understood at present. The major N transformations and fluxes are shown in Figure 3. 

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