Biological pump efficiency

Because zinc is required for the growth of phytoplankton, its availability affects the biological pump. Although zinc limitation of an entire phytoplankton community has never been demonstrated, levels of dissolved zinc are often low enough to limit many taxa (Morel et al, 1994 Sunda and Huntsman, 1995b Timmermans et al, 2001). Zinc is an integral part of the enzyme, carbonic anhydrase (Morel et al, 1994), which helps maintain an efficient supply of CO2 to Rubisco. 

One possible further impact of the decline of the diatoms lies in the identity of their probably successor. If a CaCOs-producing phytoplankter, such as coccolithophorids, steps in to utilize the NOj" and PO4 the silicon-starved diatoms leave behind, the CO2 pumping efficiency of the biological pump will decline (Robertson et al, 1994) even if the same amount of organic carbon continues to be removed to the deep sea and sediments each year. 

Figure 3 Steady-state model atmospheric PCO2 response to the efficiency of the biological pump, as indicated by the inventory of in the top 50 m of the ocean (source Archer et al, 2000a).

The global efficiency of the biological pump can be evaluated in terms of a global mean preformed nutrient concentration for surface water that is folded into the ocean interior. In the calculation of this mean preformed nutrient concentration, each subsurface water formation... 

Factors That Affect the Efficiency of the Biological Pump... 

An efficient biological pump means that a large fraction of the system s net production is removed from the surface waters via export mechanisms. Factors that affect the efficiency of the biological pump are numerous and include nutrient supply and plankton community structure. 

By optimizing the geometrical factors, a maximum pump efficiency of 90% was achieved in the case of electroplated electrodes. A deflection of more than 1.5 mm was observed. A real-time wireless operation could also be achieved. Since the materials are biocompatible, suitable uses are for biological and medical applications [132]. 

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