춘천호의 2014~2015년 평균 강수량은 800 mm 이하였으나, 2016~2017년에는 1,200 mm 이상으로 나타났다. 수온의 범위는 17.0~21.1°C, COD는 연평균 농도가 2.7~4.2 mg L-1였고, 2015년에 가장 높았으며 적은 강수량으로 체류시간이 증가하여 다른 해에 비해 높은 농도가 나타난 것으로 판단된다. TP와 TN의 연평균 농도는 각각 0.012~0.019 mg L-1와 1.272~1.922 mg L-1로 나타났으며 TN은 2014년부터 지속된 갈수현상으로 2015년이 다른 년도에 비해 높았다. 식물플랑크톤의 종 다양성 지수는 2014~2015년에 2.0 이하로 다른 년도에 비해 낮았으며, 강수량과 환경요인과의 상관 분석 결과 수온, TP 및 Chl. a가 높게 나타났다. 식물플랑크톤의 세포수는 CC3 (상류) 지점이 CC1 (하류)과 CC2 (중류) 지점보다 상대적으로 많았으며 그 이유는 갈수현상으로 수체의 안정 및 유기물이 농축되어 남조류를 포함한 식물플랑크톤이 성장하기 유리한 조건이 되었을 것으로 판단된다. 수온에 따른 식물플랑크톤의 분류군별 상관관계 결과 규조류는 음의 상관관계, 녹조류와 남조류는 양의 상관관계를 보였다. 춘천호의 식물플랑크톤은 온대호수의 천이 형태를 보이고 있으나 강우에 따라 식물플랑크톤의 종 다양성 및 발생량과 수질환경요인이 다르게 나타났을 것으로 판단된다. 본 연구는 춘천호의 수질 및 식물플랑크톤의 장기변화를 조사한 최초의 결과이며 향후 추가 연구를 위한 선행자료로 제공하고자 한다.

Effects of environmental factors on phytoplankton succession and community structure were studied in Lake Chuncheon located in Bukhan River, South Korea. The data were sampled at three sites such as CC1 (lower side), CC2 (middle side), and CC3 (upper side of Lake Chuncheon) from 2014 to 2017. The annual average precipitation in Lake Chuncheon was 992 mm during the study period (2014~2017), and the annual precipitation was lower than 800 mm in 2014 and 2015. The annual average water temperature, total phosphorus (TP), and total nitrogen (TN) ranged from 17.0 to 21.1°C, 0.012 to 0.019 mg L-1, and 1.272 to 1.922 mg L-1, respectively. The TN concentration was relatively high in 2015 compared with the other study years, as a drought continued from 2014 to 2015. When comparing the correlation between precipitation and environmental factors, water temperature (p<0.01) and TP (p<0.05) showed positive correlations with rainfall. The average numbers of phytoplankton cells by branch were 2,094, 2,182, and 3,108 cells mL-1 in CC1 , CC2, and CC3, respectively. CC3 is considered advantageous for phytoplankton growth, even in small pollution sources due to low water depth. As a result of analyzing the relationship between precipitation and phytoplankton, the correlation between the two was shown to be high for 2016 (p<0.01) and 2017 (p<0.05), which is when precipitation was high. However, the correlation was not clear to 2014 and 2015. The relationship between water temperature and phytoplankton indicated a negative correlation with diatoms (p<0.01), yet positive correlations with green algae (p<0.01) and cyanobacteria (p<0.01). Diatoms increased in spring and autumn, which are characterized by low water temperature, and green algae and cyanobacteria increased in summer, when the water temperature is high. Our findings provide a scientific basis for characteristics of phytoplankton and water quality and management at the Lake Chuncheon.

Abstract
 서 론
 재료 및 방 법
  1. 조사지점 및 조사기간
  2. 채집 및 분석방법
 결과 및 고 찰
  1. 이화학적 환경요인
  2. 식물플랑크톤의 군집 변동 및 천이
  3. 식물플랑크톤의 군집 지수
  4. 환경요인과 식물플랑크톤 군집 관계
 적 요
 REFERENCES

• 백준수(국립환경과학원 한강물환경연구소) | Jun-Soo Baek (Han River Environment Research Center, National Institute of Environmental Research)
• 윤석제(국립환경과학원 한강물환경연구소) | Seok-Jea Youn (Han River Environment Research Center, National Institute of Environmental Research)
• 김헌년(국립환경과학원 한강물환경연구소) | Hun-Nyun Kim (Han River Environment Research Center, National Institute of Environmental Research)
• 심연보(국립환경과학원 한강물환경연구소) | Youn-Bo Sim (Han River Environment Research Center, National Institute of Environmental Research)
• 유순주(국립환경과학원 한강물환경연구소) | Soon-Ju Yoo (Han River Environment Research Center, National Institute of Environmental Research)
• 임종권(국립환경과학원 한강물환경연구소) | Jong-Kwon Im (Han River Environment Research Center, National Institute of Environmental Research) Corresponding author