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Published on: September 5, 2018
Long-term discrepancy between food supply and demand in the deep eastern north pacific
1Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0202, USA. Marine and Environmental Studies Program, University of San Diego, 5998 Alcala Park, Sa.
Science (New York, N.Y.)
|May 15, 1999
Summary
Deep-sea food supply is declining in the eastern North Pacific. A 7-year study found sinking particulate organic carbon (POC) decreased, impacting sediment community oxygen consumption (SCOC) and deep-sea ecosystems.
Area of Science:
- Marine Biology
- Oceanography
- Deep-Sea Ecology
Background:
- The abyssal eastern North Pacific is a deep-sea environment characterized by limited food availability.
- Sediment community oxygen consumption (SCOC) serves as a proxy for deep-sea food demand.
- Sinking particulate organic carbon (POC) represents the primary food supply to the deep ocean.
Purpose of the Study:
- To assess long-term trends in food supply (POC) and food demand (SCOC) in the abyssal eastern North Pacific.
- To investigate the relationship between surface ocean conditions and deep-sea food availability.
- To evaluate the potential impacts of observed trends on deep-sea ecosystems and geochemical cycles.
Main Methods:
- A 7-year study was conducted to monitor POC flux and SCOC.
- Data on sea surface temperature and plankton biomass were analyzed.
- The ratio of POC to SCOC was calculated to assess food supply relative to demand.
Main Results:
- A significant long-term deficit in food supply was observed in the abyssal eastern North Pacific.
- The POC:SCOC ratio declined by 52% to 59% between 1989 and 1996.
- This decline is potentially linked to increased sea surface temperatures and decreased plankton biomass in surface waters, reducing POC export.
Conclusions:
- The eastern North Pacific deep sea is experiencing a decreasing food supply.
- Continued reduction in POC export could significantly alter deep-sea geochemical cycling.
- Observed trends may lead to profound changes in the structure and dynamics of deep-sea communities.
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