Horizontal Segregation of the Biolimiting Elements

All figures are available on the companion website in color (if applicable). 

As noted in Chapter 4, the term meridional overturning circulation, abbreviated MOC, is used to collectively describe all the water movements associated with the creation, lateral flows, and upwelling of the subsurfece water masses. 

To understand segregation, you will need a detailed understanding of these water currents. This information is provided on the oompanion website (http //elsevierdirect.com/ companions/9780120885305). 

Vertical distributions of (a) oxygen, (b) dissolved silicon (silicate is the primary chemical species), (c) nitrate, and (d) phosphate at selected latitudes within the Atlantic (20 to 30°W), Indian (91 to 95°W), and Pacific (135 to 158°W) oceans. These are WOCE data obtained from Java Ocean Atlas. 

Plankton produce biogenic particles in the surfece waters of all the ocean basins. Most of these particles sink into the deep sea and are then remineralized. The rain of biogenic particles causes the nutrient concentration of the deep-water masses to increase as they move through the ocean basins for two reasons. First, the further a deep-water mass has traveled from its site of formation, the greater the amount of particles it will 

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Nutrients are carried back to the sea surface by the return flow of deep-water circulation. The degree of horizontal segregation exhibited by a biolimiting element is thus determined by the rates of water motion to and from the deep sea, the flux of biogenic particles, and the element s recycling efficiency (/and from the Broecker Box model). If a steady state exists, the deep-water concentration gradient must be the result of a balance between the rates of nutrient supply and removal via the physical return of water to the sea surface. 

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