Phytoplankton nutrient

Fisher, T.R., Harding, L., Stanley, D.W., and Ward, L.G (1988) Phytoplankton, nutrients, and turbidity in the Chesapeake, Delaware, and Hudson estuaries. Estuary. Coastal Shelf Sci. 27, 61-93. 

Nielsen, S.L., Sand-Jensen, K., Borum, J., and Geertz-Hansen, O. (2002) Phytoplankton, nutrients, and transparency in Danish coastal waters. Estuaries 25, 930-937. 

Philippart CJM, Cadee GC, van Raaphorst W, Riegman R (2000) Long-term phytoplankton-nutrient interactions in a shallow coastal sea algal community structure, nutrient budgets, and denitrification potential. Limnol Oceanogr 45 131-144... 

Rees, A. P., Joint, I., and Donald, K. M. (1999b). Early spring bloom phytoplankton-nutrient dynamics at the Celtic Sea Shelf Break. Deep Sea Res. 146, 483—510. 

BeardaH, J., Young, E., and Roberts, S. (2001). Approaches for determining phytoplankton nutrient limitation. Aquat. Sci. 63, 44—69. 

Litchman, E., Klausmeier, C. A., and Bossard, P. (2004). Phytoplankton nutrient competition under dynamic light regimes. Limnol. Oceanogr. 49, 1457—1462. 

The vertical distribution of dissolved cadmium concentration in the oceans follows a profile typical of phytoplankton nutrients from a few picomolar at the... 

Heath MR, Richardson K, KiOrboe T Optical assessment of phytoplankton nutrient depletion, J Plankton Res 12(2) 381—396, 1990. 

The ocean receives Cd mobilized from the crust through riverine and atmospheric input. These fluxes are poorly constrained at present but given an ocean Cd inventory of 10 ° g, the residence time of Cd is similar to biologically utilized elements and approaches lO years [70]. The predominant form of Cd in the ocean is in the dissolved phase with concentrations ranging from 1 to 1000 pmol kg [76-78]. The vertical distribution of Cd in the oceanic water column resembles profiles of phytoplankton nutrients, with minimum concentrations at the surface that increase to maximum values in the main thermocline and remain relatively constant from there to the ocean bottom (Figure 2) [76-78]. Particulate Cd concentrations are significantly lower and fall between 0.04 and 4 pmol kg and are, conversely, maximal in surface waters [79]. This distribution reflects the uptake of Cd by photosynthetic plankton at the surface and the sinking and subsequent decomposition of particulate matter in the water colunrn. 

Problems associated with excessive levels of nutrients and unwanted nuisance species have already been mentioned. There are cases in which intentional fertilization is used by aquaculturists in order to produce desirable types of natural food for the species under culture. Examples of this approach include inorganic fertilizer appHcations in ponds to promote phytoplankton and zooplankton blooms that provide food for young fish such as channel catfish, the development of algal mats through fertilization of milkfish ponds, and the use of organic fertilizers (from Hvestock and human excrement) in Chinese carp ponds to encourage the growth of phytoplankton, macrophytes, and benthic invertebrates. In the latter instance, various species of carp with different food habits are stocked to ensure that all of the types of natural foods produced as a result of fertilization are consumed. 

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. 

Trace metals can serve as essential nutrients and as toxic substances (Sunda et al, 1991 Frausto da Silva and Williams, 1991). For example, cobalt is a component of vitamin B-12. This vitamin is essential for nitrogen fixing algae. In contrast, copper is toxic to marine phytoplankton at free ion concentrations similar to those found in seawater (Sunda and... 

Oceanic surface waters are efficiently stripped of nutrients by phytoplankton. If phytoplankton biomass was not reconverted into simple dissolved nutrients, the entire marine water column would be depleted in nutrients and growth would stop. But as we saw from the carbon balance presented earlier, more than 90% of the primary productivity is released back to the water column as a reverse RKR equation. This reverse reaction is called remineralization and is due to respiration. An important point is that while production via photosynthesis can only occur in surface waters, the remineralization by heterotrophic organisms can occur over the entire water column and in the underlying sediments. 

Chisholm S. W. and Morel, F. M. M. (eds) (1991). What controls phytoplankton production in nutrient-rich areas of the open sea Limnol. Oceanogr. 36, 1507-1965. 

Frost, R. W. and Franzen, N. C. (1992). Grazing and iron limitation in the control of phytoplankton stock and nutrient concentration A chemostat analogue... 

Counterexamples teach a lesson that these exaggerations of aquatic biological activity are highly idiosyncratic and depend on the fluxes of nutrients, the types of phytoplankton ecosystems that are involved, and - most importantly - the local and regional circulations of the aquatic system. For example, the Mediterranean Sea is landlocked and has many large pollution sources, but the large flux of nutrient-poor ("impoverished") water from the Atlantic... 

Ocean prevents eutrophication. Much more water flows into the Mediterranean Sea than is required to replace evaporation from it. The excess, high salinity water exits Gibraltar below the water flowing in af fhe surface. Nufrients that enter the Mediterranean Sea from pollution sources are utilized by marine phytoplankton that sinks and exits with the outflow. Another example is that estuaries often have lower salinity or even freshwater at the surface with a denser saline layer at the bottom. An estuarine circulation occurs with nutrients being trapped in the saline bottom water. 

Roach WJ, Grimm NB (2009) Nutrient variation in an urban lake chain and its consequences for phytoplankton production. J Environ Qual 38 1429-1440... 

---