Coastal upwelling is the best known type of upwelling, and the most closely related to human activities as it supports some of the most productive fisheries in the world, like small pelagics (sardines, anchovies, etc.). Deep waters are rich in nutrients which include nitrate and phosphate, themselves the result ofdecomposition of sinking organic matter (dead/detrital plankton) from surface waters. When brought to the surface, these nutrients are utilized by phytoplankton, along with dissolved CO2 (carbon dioxide) and light energy from the sun, to produce organic compounds, through the process of photosynthesis. Upwelling regions therefore result in very high levels of primary production (the amount of carbon fixed byphytoplankton) in comparison to other areas of the ocean. High primary production propagates up the food chain because phytoplankton are at the base of the oceanic food chain. Regions of upwelling include coastal Peru, Chile, Arabian Sea, western South Africa, eastern New Zealand, southeastern Brazil and the California coast.
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