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Assessment of Eutrophication Using Trophic State Index and Water Quality Characteristics of Saemangeum Lake

새만금호의 수질 특성 및 영양상태지수를 이용한 부영양화 평가

  • 김종구 (군산대학교 환경공학과)
  • Received : 2023.08.09
  • Accepted : 2023.10.27
  • Published : 2023.10.31

Abstract

We evaluated the eutrophication of Saemangeum Lake, which causes abnormal growth of algae, using the Carlson index. Eutrophication characteristics of Saemangeum Lake were analyzed. For the study, water quality surveys were conducted at 7 stations in Saemangeum Lake every month in 2021. The concentration of Chl.a was slightly higher in the Mankyeong water system in winter, and slightly higher in the Dongjin water system in spring and summer, but overall, except for some periods, the concentration was similar to or lower than the lake water quality environmental standard of class 3. COD showed water quality similar to or above the lake quality environmental standard of grade 4 in both the Mankyeong and Dongjin water systems in the summer and Autumn. TOC concentrations were within lake water quality standard 3 at all sites. Total phosphorus concentrations exceeded the lake water quality standard of Class 4 and were higher in January and August after rainfall. In the correlation analysis between water quality factors, the correlation of organic matter, total phosphorus, and total nitrogen to salinity was relatively high. This reflected the water quality characteristics of freshwater, brackish water, and seawater areas due to seawater inflow through the drainage gate and freshwater inflow through upstream rivers. According to the characteristics of eutrophication fluctuations in Saemangeum Lake by trophic state index, the indices of Chl.a, SD, and TN showed water quality in the early stage of eutrophication, while the TP index showed a severe eutrophication state. The magnitude of the eutrophication index among water quality components was TSI(TP) > TSI(TN) > TSI(SD) > TSI(CHL) in all water systems. Quadrant analysis of the deviation of TSI(CHL) from TSI(TP) and TSI(SD) on a two-dimensional plane showed that there was no limiting effect of total phosphorus on algal growth in all water systems. In addition, the factors af ecting light attenuation appeared to be dominated by small particulate matter from outside sources.

조류의 이상증식을 일으키는 새만금호 부영양화를 평가하기 위해 Carlson 지수를 적용하였다. 연구를 위해 2021년 월별로 새만금호내 총 7개 정점에서 수질조사를 실시하였다. Chl.a의 농도는 동계에는 만경수계가 약간 높았고, 춘계와 하계에는 동진수계가 약간 높게 나타났으나, 일부 시기를 제외하고는 전체적으로 호소 수질환경기준 3등급과 비슷하거나 낮은 농도를 나타내었다. COD는 만경수계와 동진수계 모두 하계와 추계에 호소 수질환경기준 4등급과 유사하거나 상회하는 수질을 나타내었다. TOC는 모든 지점에서 3등급 이내의 수질을 보였다. 총인 농도는 호수 수질환경기준 4등급을 초과하였고, 월별로는 1월과 강우 후 8월에 높게 나타났다. 수질인자간의 상관성 분석에서 염분 농도에 대한 유기물, 총인, 총질소의 상관성이 상대적으로 높게 나타나 배수갑문을 통한 해수유입과 상류 하천을 통한 담수 유입에 의한 담수역, 기수역, 해수역의 수질 특징을 반영하고 있었다. 영양상태지수에 의한 새만금호의 부영양화 변동 특성을 보면, Chl.a와 SD, TN의 지수에서 부영양화 초기 단계의 수질을 보였으며, TP 지수의 경우 심각한 부영양화 상태를 나타내고 있었다. 수질인자간 부영양화 지수의 크기는 모든 수계에서 TSI(TP) > TSI(TN) > TSI(SD) > TSI(CHL)의 순으로 나타났다. TSI(CHL)에 대한 TSI(TP) 및 TSI(SD)와의 편차를 2차원 평면으로 나타낸 사분면 분석 결과를 보면, 조류 성장에 대한 총인이 영향에서는 모든 수계에서 대부분의 총인(TP)에 의한 제한적 영향은 나타나지 않았으며, 빛 감쇠에 영향을 미치는 인자는 외부로부터 유입되는 적은 입자상 물질에 의한 영향이 크게 나타나는 것으로 평가할 수 있다.

Keywords

References

  1. Ahn, D. H., S. K. Han, S. J. Jo, and M. Lim(2013), Water Quality Assessment for Geumgang River Area using th Korean Trophic State Index, J. Wat. Treat., Vol. 21, No. 3, pp. 13-20.
  2. Devi Prasad, A. G. and Siddaraju(2012), Carlson's Trophic State Index for the assessment of trophic status of two Lakes in Mandya district, Advances in Applied Science Research, 3(5), pp. 2992-2996.
  3. An, K. G.(2000), Monsoon inflow as a major source of in-lake phosphorus, Korean Journal of Limnology, 33(3), pp. 222-229.
  4. Choi, C. H., S. W. Jung, S. M. Yun, S. H. Kim, and J. G. Park(2013), Changes in Phytoplankton Communities and Environmental Factors in Saemangeum Artificial Lake, South Korea between 2006 and 2009, Korean J. Environ. Biol., Vol. 31, No. 2, pp. 213-224. https://doi.org/10.11626/KJEB.2013.31.3.213
  5. Carlson, R. E.(1977), A Trophic state index for lakes, Limnology ans Oceanography. 22(2), pp. 361-369. https://doi.org/10.4319/lo.1977.22.2.0361
  6. Carlson, R. E.(1991), Expanding the trophic state concept to identify non-nutrient limited lakes and reservoirs, Enhancing the State's Lake Management Programs 1991, pp. 59-71.
  7. Edmondson, W. T.(1980), Secchi disk and chlorophyll, Limnology and Oceanography 25, pp. 378-379. https://doi.org/10.4319/lo.1980.25.2.0378
  8. Havens, K. E., H. J. Carrick, E. F. Lowe, and M. F. Coveney (1999), Contrasting relationships between nitrientsm chlorophyll a and Secchi transparency in two shallow eutrophic lakes ; Lakes Okeechobee ans Apopka (Florida, USA). lake and Reservoir Management 15, pp. 298-309. https://doi.org/10.1080/07438149909354125
  9. Havens, K. E.(2000), Using Trophic State Index (TSI) Values to Draw Inferences Regarding Phytoplankton Limiting Factors and Seston Composition from Routine Water Quality Monitoring Data. Korean J. Limnol. 33(3), pp. 187-196.
  10. Kim, B. C. and D. S. Kong(2019), Examination of the Applicability of TOC to Korean Trophic State Index (TSIko), J. of Korean Soc. on Water Environ., Vol. 35, No. 3, pp. 271-277.
  11. Kim, B. and Y. Kim(2004), Phosphorus cycle in a deep reservoir in Asian monsoon area (Lake Soyang, Korea) and the modeling with a 2-D hydrodynamic water quality model [CE-QUALW2], Korean Journal of Limnology, 37(2), pp. 205-212. [Korean Literature]
  12. Kong, D. S. and B. C. Kim(2019), Suggestion for Trophic State Index of Korean lakes (Upper Layer), J. of Korean Soc. on Water Environ., Vol. 35, No. 4, pp. 340-351.
  13. Kong, D. S.(2019), Statistical Analysis on Water Quality Chaeacteristics of Large Lakes in Korea, J. of Korean Soc. on Water Environ., Vol. 35, No. 2, pp. 165-180.
  14. Kim, E. S., K. B. Sim, S. D. Kim, and H. I. Choi(2012), Water Quality Assessment for Reservoirs using th Korean Trophic State Index, J. of Korean Soc. on Water Environ., Vol. 28, No. 1, pp. 78-83.
  15. Kim, J. G.(2023), Evaluation of Water Quality Characteristics of Saemangeum Lkae Using Statistical Analysis, J. the korean Soc. of Marine environ. & Safety, Vol. 29, No. 4, pp. 297-306. https://doi.org/10.7837/kosomes.2023.29.4.297
  16. Kim, N. H., Andy S. Choi, and C. O. Oh(2020), Assessing Public Preferences for Politics on Seawater Flowing of the Saemangeum Reclamation Site Using Choice Experiemnts, Environmental Police, Vol. 28, No. 4, pp. 87-111.
  17. Kratzer, C. R. and P. L. Brezonik(1981), A Carlson type trophic state index for nitrogen in Florida lakes. Water Resources Bulletin 17, pp. 713-715.
  18. Ministry of Environment(2016), Saemangeum Lake Ecosystem and Sediment Monitoring (III), Final Report. Saemangeum National Environmental Protection Agency, pp. 48-49.
  19. Ministry of Environment(2018), Saemangeum Lake Sediment Monitoring (V), Final Report. Saemangeum National Environmental Protection Agency, pp. 48-49.
  20. Park, H. J. and K. G. An(2007), Trophic State Index (TSI) and Emprical Models Based on Water Quality Parameters in Korean Reservoirs, Korean J. Limnol., Vol. 40, No. 1, pp. 14-30.
  21. Park, J. G.(2005), Water Environmental Factors and Trophic States in Lake Daecheong, Korean J. Limnol., Vol. 38, No. 3, pp. 382-392.
  22. Park, S. C., J. O. Kim, W. B. Lee, S. H. Park, and S. D. Lee (2017), Characteristics of Eutrophication of Yeongsan River Area using the Trophic State Index (TSIko), J. Wat. Treat., Vol. 25, No. 6, pp. 3-15.
  23. Park, S. H., J. W. Lee, J. H. Kim, and S. H. Baek(2013), Fish Distribution and Salinity in the Saemangeum Reservoir, Korean J. Environ. Biol., Vol. 31, No. 4, pp. 411-418. https://doi.org/10.11626/KJEB.2013.31.4.411
  24. Park, S. H., J. G. Kim, and M. S. Kwon(2023), Development of Mass Proliferation Control Algorithm of Phytoplankton Using Artificial Neutral Network, J. the korean Soc. of Marine environ. & Safety, Vol. 29, No. 5, pp. 435-444. https://doi.org/10.7837/kosomes.2023.29.5.435
  25. Ryu, J. W., J. H. Choi, S. D. Jeong, K. H. Kang, D. C. Nam, M. P. Kim, S. R. Park, J. J. Park, and T. S. You(2018), Investigation of Pollutant Load of Saemangeum Watershed (Mangyeong River, Dongjin River). Jeollabukdo Institute of Health & Environment Research, Vol. 27, pp. 33-80.
  26. Shin, Y. R., J. Y. Jang, J. H. Choi, and K. W. Jung(2012a), Hydrodynamic Modeling of Saemangeum Reservoir and Watershed using HSPF and EFDC, J. of Korean Soc. on Water Environ., Vol. 28, No. 3, pp. 384-393. https://doi.org/10.5572/KOSAE.2012.28.4.384
  27. Shin, Y. R., J. Y. Jung, J. H. Choi, and Y. K. Cho(2012b), The Comparsion of Grid Resolutions using EFDC in Saemangeum Reservoir, J. of Korean Soc. on Water Environ., Vol. 28, No. 5, pp. 646-656.