The structure and functioning of the coastal upwelling system off central/southern Chile

摘要

Coastal upwelling zones in eastern boundary current systems (EBCs) comprise a relatively small portion of the world oceans ( < 2%) but, due to their very high biological production, they sustain most of the global fisheries ( > 23% of fish catch) and, thereby, the economy of several countries. At the same time, these zones act as key areas for carbon exchange between the coastal zone and the open ocean, as well as between the ocean and the atmosphere. Among these zones, the Humboldt Current System (HCS) is one of the most productive ones (mean primary production of ca. 750 mg C m~(-2) d~(-1)) and supports a strong fishery off Peru and Chile (Alheit and Bernal, 1993; Kudela et al., 2005). Also, the HCS contains one of the shallowest, and most extensive, oxygen minimum zones (OMZs) located in the coastal areas of EBC systems (Morales et al., 1999; Escribano et al., 2004).