Biogeochemical modelling

Risks and Trends (Modelling and Mapping Manual, 2004)3. Moreover, many research groups engaged in biogeochemical model development make them available as freeware . Annual reports published by the National Focal Centers of the LRTAP Convention as provides insights on methodologies and partially input data for the CLL calculations. 

Biogeochemical Model Profile for Calculation of Critical Loads of Acidity The biogeochemical model PROFILE has been developed as a tool for calculation of critical loads on the basis of steady-state principles. The steady-state approach implies the following assumptions ... 

Since the biogeochemical model PROFILE includes such important characteristics as mineral abundance, another model UPPSALA has been created that allows the researcher to calculate the soil mineralogical composition on the basis of total element content. The combination of these models (PROFILE and UPPSALA) gives the possibility to use existing soil and ecosystem databases for calculating critical loads of acidity in broad-scale regions. 

PROFILE is a biogeochemical model developed specially to calculate the influence of acid depositions on soil as a part of an ecosystem. The sets of chemical and biogeochemical reactions implemented in this model are (1) soil solution equilibrium, (2) mineral weathering, (3) nitrification and (4) nutrient uptake. Other biogeochemical processes affect soil chemistry via boundary conditions. However, there are many important physical soil processes and site conditions such as convective transport of solutes through the soil profile, the almost total absence of radial water flux (down through the soil profile) in mountain soils, the absence of radial runoff from the profile in soils with permafrost, etc., which are not implemented in the model and have to be taken into account in other ways. 

Savchuk, O.P. (2000) Studies of the assimilation capacity and effects of nutrient load reductions in the eastern Gulf of Finland with a biogeochemical model. Boreal Env. Res. 5, 147-163. 

Since Phaeocystis plays a key role in element fluxes relevant to climate the results presented here have implications for biogeochemical models of cycling of carbon and sulphur. Sea-to-air exchange of C02 and dimethyl sulphide (DMS) has been calculated on the basis of measurements during single-year cruises. The considerable annual variation in phytoplankton and in its Phaeocystis component reported here does not warrant extrapolation of such figures. 

Lacroix G, Ruddick R, Park Y, Gypens N, Lancelot C (2007) Validation of the 3D biogeochemical model MIRO CO with field nutrient and phytoplankton data and MERIS-derived surface chlorophyll a images. J Mar Syst 64 66-88... 

Fig. 10.8. Simple biogeochemical model for metal mineral transformations in the mycorhizosphere (the roles of the plant and other microorganisms contributing to the overall process are not shown). (1) Proton-promoted (proton pump, cation-anion antiport, organic anion efflux, dissociation of organic acids) and ligand-promoted (e.g. organic adds) dissolution of metal minerals. (2) Release of anionic (e.g. phosphate) nutrients and metal cations. (3) Nutrient uptake. (4) Intra- and extracellular sequestration of toxic metals biosorption, transport, compartmentation, predpitation etc. (5) Immobilization of metals as oxalates. (6) Binding of soluble metal species to soil constituents, e.g. clay minerals, metal oxides, humic substances.

Verrecchia, E. P. Dumont, J.-L. (1996). A biogeochemical model for chalk alteration by fungi in semiarid environments. Biogeochemistry, 35, 447-70. 

Belevtsev, Ya.N. and Mel nik, Yu.P., 1976. Biogeochemical model of genesis of Prccambrian ferruginous formations. Int. Geol. Congr., 25th, (Canberra), Abstr., I 152-153. 

Sverdrup, H., M. Alveteg, S. Langan, and T. Paces. 1995. Biogeochemical Modelling of small catchments." In Solute Modelling in Catchment Systems, ed. S. T. TrudgUl Oohn Wiley Sons, Chichester), pp. 75-100. 

Richey J.E., The Amazon River System A Biogeochemical Model. In Mitteilungen aus dem Geologisch-Palaontologisch Institut der Universitat Hamburg , Heft 52 (E.T. Degens, Ed.), 365-378 (1982). 

Ward et al., 1989b). A large role for in situ nitrification to supply the phytoplankton demand is also supported by biogeochemical models... 

LOICZ. Biogeochemical modeling node. http //data.ecology.su.se/MNODE. 

Gordon, D. C., Boudreau, P., Mann, K. H., Ong,. E., Silvert, W., Smith, S. V., Wattayakom, G., Wulff, F., and Yanagi, T. (1996). LOICZ Biogeochemical Modeling Guidelines. Land-Ocean Interactions in the Coastal Zone (LOICZ) R S 95-5. LOICZ, Texel, The Netherlands. 

Christian, J. R., VerscheU, M. A., Muitugudde, R., Busalacchi, A. J., and McClain, C. R. (2002a). Biogeochemical modelling of the tropical Pacific Ocean. I Seasonal and interannual variability. Deep-Sea Res. II49, 509—543. 

Section 8.07.3), and some methods for quantifying decomposition rates (Section 8.07.4). This is followed by a discussion of the mechanisms behind decomposition (Section 8.07.5), humification (Section 8.07.6), and the controls on these processes (Section 8.07.7). We conclude the chapter with a brief discussion on how current biogeochemical models incorporate this information (Section 8.07.8). 

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