Inorganic Nutrient Distributions in Association with Thermocline at KOMO Station in the Northeast Equatorial Pacific Ocean during 1995-2002

북동태평양 KOMO 정점에서 수온약층에 따른 무기영양염 분포 특성(1995-2002)

  • Son, Seung-Kyu (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Son, Ju-Won (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Kim, Kyeong-Hong (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Kang, Jung-Hoon (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Chi, Sang-Bum (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Yoo, Chan-Min (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Park, Cheong-Kee (Marine Geoenvironment and Resources Research Division, KORDI) ;
  • Kim, Woong-Seo (Marine Geoenvironment and Resources Research Division, KORDI)
  • 손승규 (한국해양연구원 해저환경.자원연구본부) ;
  • 손주원 (한국해양연구원 해저환경.자원연구본부) ;
  • 김경홍 (한국해양연구원 해저환경.자원연구본부) ;
  • 강정훈 (한국해양연구원 해저환경.자원연구본부) ;
  • 지상범 (한국해양연구원 해저환경.자원연구본부) ;
  • 유찬민 (한국해양연구원 해저환경.자원연구본부) ;
  • 박정기 (한국해양연구원 해저환경.자원연구본부) ;
  • 김웅서 (한국해양연구원 해저환경.자원연구본부)
  • Received : 2004.04.19
  • Accepted : 2004.06.01
  • Published : 2004.06.30


Annual variations of inorganic nutrients such as nitrate(+nitrite), phosphate and silicate in association with thermocline were investigated in the upper 200 m of the water column at KODES Long-term Monitoring (KOMO) station in the northeast equatorial Pacific from 1995 to 2002. Global climatic disturbances such as El Nino and La Nina, should have affected KODES area during the study period. In 1995-97 and 2000-2002, a thermocline where temperatures rapidly decrease with depth, was formed at 50-70 m water depth. Nutrient depletion, specially for nitrate and phosphate, was extended down to approximately 50 m depth, which coincided with the surface mixed layer depth. In 1998 and 1999, however a very fluctuating thermocline was observed at 20-100 m water depth. In the photic zone (up to 100 m depth), depth integration of nitrate, phosphate and silicate ranged from 2.02 to $23.14\;gN/m^2$, from 0.87 to $4.05\;gP/m^2$ and from 35.67 to $176.21\;gSi/m^2$, respectively. As a result of changes in the water column structures, nutrient concentrations also showed fluctuation parallel to the changes of thermocline in the study area.


Grant : 심해저광물자원탐사사업

Supported by : 해양수산부


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