동해 연안의 영양염의 장기간 변동 특성을 파악하기 위하여 2013년부터 2017년까지 5년간 격월별로 속초, 죽변, 감포 연안의 3개 정점에서 수온, 염분, 용존산소, 영양염을 조사하였다. 5년 동안 동해연안에서 수온은 1.2∼28.8 ℃, 염분은 30.63∼34.79, 용존산소는 3.53∼7.64 mL/L의 범위였으며 수온의 연직분포 변동에 따라 환경요인들의 분포와 변동이 결정되고 있었고, 북한한류수의 남하 유입에 의해 2015년과 2016년에 속초연안에서 용존산소가 높게 나타났다. 용존무기질소(DIN, NH4-N+NO2-N+NO3-N)의 농도는 0.11∼24.19 μM, 인산 인의 농도는 0.01∼1.75 μM, 규산 규소의 농도는 0.17∼32.80 μM의 범위 내에서 변동하였다. 동해연안의 N:P 비는 0.7∼54.3(평균 15.2), N:P 기울기는 해역별로 11.67∼13.75의 범위로, Redfield 비(16)보다 낮아, 동해연안에서는 대체로 질산 질소가 식물플랑크톤의 성장을 제한하는 영양염인 것으로 나타났다. 전체 N:P 기울기의 상관관계(R2)는 0.95로 높아 주변 육상 또는 비점오염원의 영향은 크지 않은 것으로 나타났다. 결론적으로 동해 연안에서 영양염의 시·공간적 변동은 수온의 성층구조 변동에 따른 저층 영양염의 혼합에 따라 결정되었으며, 외부 수괴 유입과 연안 용승 등의 물리적 요인에 의해 주로 영향을 받고, 육상으로부터 유입에 의한 영향은 적은 것으로 나타났다.

To investigate the long-term variation characteristics of nutrients in the east coast of Korea, water temperature, salinity, dissolved oxygen, and nutrients were measured at three stations of Sokcho, Jukbyeon and Gampo coasts for five years from 2013 to 2017. For five years, the water temperature of the East Sea coast was in the range of 1.2∼28.8 ℃, the salinity was in the range of 30.63∼34.79 and the dissolved oxygen (DO) was in the range of 3.53∼7.64 mL/L. Distribution and variation of the water environment factors in the study area were determined by the vertical stratification of water column and distribution of water temperature. The high DO concentration in Sokcho coast From 2015 to August 2016 is presumed to be the result of the southward inflow of North Korean Cold Water (NKCW). Concentrations of dissolved inorganic nitrogen (DIN, NH4-N+NO2-N+NO3-N) ranged 0.11∼24.19 μM, phosphate concentration ranged 0.01∼1.75 μM, and silicate ranged 0.17∼32.80 μM. The N:P ratio was in the range of 0.7∼54.3 (mean 15.2) and the N:P slope was in the range of 11.67∼13.75. The N:P ratios in this study were lower than the Redfield ratio (16), indicating that nitrate did act as a limiting factor in phytoplankton growth. The correlation (R2) of total N:P ratio was as high as 0.95, indicating that the effect of the surrounding land or non-point sources was not significant. In conclusion, the spatial and temporal variation of nutrients in the east coast of Korea was determined by the vertical mixing of water mass with thermocline and mainly affected by physical factors such as influx of external water masses and coastal upwelling, and the influences from inflows from the land were minimal.

요 약
 Abstract
 1. 서 론
 2. 재료 및 방법
 3. 결과 및 고찰
  3.1 수온, 염분, 용존산소 변동
  3.2 영양염 변동
 4. 결 론
 References

• 권기영(국립수산과학원 연구기획과) | Kee-Young Kwon (Research and Development Planning Division, National Institute of Fisheries Science)
• 심정희(국립수산과학원 동해수산연구소 자원환경과) | Jeong Hee Shim (East Sea Fisheries Research Institute, National Institute of Fisheries Science) Corresponding Author
• 심정민(국립수산과학원 동해수산연구소 자원환경과) | Jeong-Min Shim (East Sea Fisheries Research Institute, National Institute of Fisheries Science)