Phytoplankton model

Mongin, M., Nelson, D. M., Pondaven, P., Brzenzinski, M. A., and Treguer, P. (2003). Simulation of upper-ocean biogeochemistry with a flexible-composition phytoplankton model C, N, and Si cyKng in the western Sargasso Sea. Deep-Sea Research Part A-Oceanographic Research Papers 50, 1445-1480. 

P.J. Neale, J.J. Fritz, R.F. Davis (2001). Effects of UV on photosynthesis of Antarctic phytoplankton Models and applications to coastal and pelagic assemblages. Rev. Chil. Hist. Nat., 74, 283-292. 

Conservation of mass has been successfully applied to the modeling of the dissolved oxygen distribution in natural waters as well as the distribution of salinity and other dissolved substances. The resulting models have proved useful in guiding engineering and management decisions concerned with the efficient utilization of water resources and the protection of their quality. It is felt that the phytoplankton model presented... 

Other models have been proposed which follow the outlines of the equations already discussed. Equations with parameters that vary as a function of temperature, sunlight, and nutrient concentration have been presented by Davidson and Clymer (9) and simulated by Cole (10). A set of equations which model the population of phytoplankton, zooplankton, and a species of fish in a large lake have been presented by Parker (II). The application of the techniques of phytoplankton modeling to the problem of eutrophication in rivers and estuaries has been proposed by Chen (12). The interrelations between the nitrogen cycle and the phytoplankton population in the Potomac Estuary has been investigated using a feed-forward-feed-back model of the dependent variables, which interact linearly following first order kinetics (13). 

The most extensive investigation of the relationship between the growth rate of natural phytoplankton populations and the significant environmental variables, within the context of phytoplankton models, is that of Riley et al. (1949) (5). The expression which results from their work is... 

A model of the dynamics of phytoplankton populations based on the principle of conservation of mass has been presented. The growth and death kinetic formulations of the phytoplankton and zooplankton have been empirically determined by an analysis of existing experimental data. Mathematical expressions which are approximations to the biological mechanisms controlling the population are added to the mass transport terms of the conservation equation for phytoplankton, zooplankton, and nutrient mass in order to obtain the equations for the phytoplankton model. The resulting equations are compared with two years data from the tidal portion of the San Joaquin River, California. Similar comparisons have been made for the lower portion of Delta and are reported elsewhere (62). 

The application of the phytoplankton model to the San Joaquin River was sponsored by the California Water Resources Commission and carried out by Hydroscience Inc. 

Changes in surface temperature elsewhere in the globe are likely to have a lesser impact on carbon or DMS production. For example, the warming that a doubling of atmospheric COj could produce in the Southern Ocean has been modelled to lead to decreased carbon uptake, but enhanced biological productivity, due to the temperature effect on phytoplankton growth." This would lead to an approximately 5% increase in DMS production and a lesser increase in CCN. There is thus a negative feedback here, but only of minor impact. 

In this way, the near-linear chlorophyll-phosphorus relationship in lakes depends upon the outcome of a large number of interactive processes occurring in each one of the component systems in the model. One of the most intriguing aspects of those components is that the chlorophyll models do not need to take account of the species composition of the phytoplankton in which chlorophyll is a constituent. The development of blooms of potentially toxic cyanobacteria is associated with eutrophication and phosphorus concentration, yet it is not apparent that the yield of cyanobacterial biomass requires any more mass-specific contribution from phosphorus. The explanation for this paradox is not well understood, but it is extremely important to understand that it is a matter of dynamics. The bloom-forming cyanobacteria are among the slowest-growing and most light-sensitive members of the phytoplankton. ... 

In the first stages of the development of an Action plan all control options are considered. In the case of lakes, this process is aided by a PC-based expert system , PACGAP, which looks at the physical and chemical characteristics of the lake to determine the most likely option for control. Once further, more detailed information has been collected on the lake s nutrient inputs and other controlling factors, amore complex interactive model can be used (Phytoplankton Response To Environmental CHange, PROTECH-2) to define the efficacy of proposed control options more accurately. This model is able to predict the development of phytoplankton species populations under different nutrient and stratification regimes. 

Frost, R. W. (1987). Grazing control of phytoplankton stock in the open subarctic Pacific ocean a model assessing the role of mesozooplankton, particularly the large calanoid copepods Neocalanus spp. Mar. Ecol. Prog. Ser. 39, 49-68. 

The refinements made to the entire model setup include a higher model resolution, the implementation of most recent ECH AM, MPIOM and HAMOCC versions, the usage of assimilated satelhte data for surface phytoplankton distribution, and the usage of a more realistic description of sinking organic matter in the ocean. 

Although the adjustment of model phytoplankton concentrations takes places every month, not all shallow water locations are affected by it every month. Since MERIS is an optical sensor, light availability limits its ability to measure ocean colour. Hence solar angle and clouds determine, whether assimilation is possible or not. The number of months in which is assimilation is possible is higher for locations close to the equator than locations at higher latitudes (Figure 2. lb)). 

Fig. 2.5 Timeseries of daily phytoplankton, zooplankton, dissolved organic carbon, detritus, and phosphorus concentration, and photosyntesis over one model year at two location the shelf seas of the Pacific Ocean, 170 E 65 N and 140 E 10 S.

Campbell, P. G. C., Errecalde, O., Fortin, C., Hiriart-Baer, W. R. and Yigneault, B. (2002). Metal bioavailability to phytoplankton - applicability of the biotic ligand model, Comp. Biochem. Physiol. C, 133, 189-206. 

Sunda, W. G. and Huntsman, S. A. (1998). Processes regulating cellular metal accumulation and physiological effects phytoplankton as model systems, Sci. Total Environ., 219, 165-181. 

Vigneault, B., Percot, A., Lafleur, M. and Campbell, P. G. C. (2000). Permeability changes in model and phytoplankton membranes in the presence of aquatic humic substances, Environ. Sci. Technol., 34, 3907-3913. 

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