Journal of Environmental Impact Assessment (환경영향평가)

Korean Society of Environmental Impact Assessment (한국환경영향평가학회)
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The Study on the Prediction of Algae Occurrence by the Multiple Regression Analysis After Weir Construction at Namhan River

다중회귀분석을 이용한 남한강 내 보 건설 후 조류 발생량 예측

  • Oh, Seung-Eun (Department of Health Environmental and Safety, Eulji University) ;
  • Ahn, Hong-Kyu (Hydro Science and Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Chae, Soo-Kwon (Department of Health Environmental and Safety, Eulji University)
  • 오승은 (을지대학교 보건환경안전학과) ;
  • 안홍규 (한국건설기술연구원 수자원하천연구소) ;
  • 채수권 (을지대학교 보건환경안전학과)
  • Received : 2017.11.20
  • Accepted : 2017.12.13
  • Published : 2017.12.31
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Abstract

This study was classified into two groups, normal season group and drought season group, by the cluster analysis using the weather and water quality data from 2012 to 2015, using SPSS 18 version. Also each cluster was classified into three spaces, Gangcheon, Yeoju and Ipoh weir. We performed the multiple regression analysis with each monthly data that concentration of Chl-a was more than algae warming level. 6 groups classified in time and space were analyzed by the correlation analysis between concentration of Chl-a and 3 weather, 11 water quality and discharge factors. We developed Chl-a prediction equations of each group with independent variables of the multiple regression analysis applying to the correlation result. The result of cluster analysis was that the period was divided into two groups, normal group(2012-2013) that total annual precipitation rate was normal and drought group(2014-2015) that total annual precipitation rate was less than 1,000 mm/hr, in time. The months that concentration of Chl-a was more than algae warming level in each group classified by cluster analysis were that the normal group was 3~8 and drought group was 3 and 6~10. The correlation result between Chl-a and weather, water quality and discharge factors for each 6 group was that relationships between Chl-a and water, discharge factors were high in the drought group more than in normal group at all weirs. This was influenced by velocity reduction and increasing HRT according to the intense drought. Weather, water quality and discharge factors that were high correlation with Chl-a were applied to independent variables of Chl-a prediction equations and each equations were developed. Among them, Each adjusted R square of Prediction equations for Chl-a in each group at Ipoh weir where is located in Namhan river downstream and is directly connected to Paldang dam were normal group = 0.920 and drought group = 0.818. It's showed the high linear.

본 연구는 SPSS(18 version)를 사용하여 남한강 보를 완공한 후에 해당되는 2012년부터 2015년까지의 기상, 수질 자료로 군집분석한 결과에 의해 평수기그룹과 가뭄기그룹으로 분류하고, 각 기간 그룹별로 강천보, 여주보 및 이포보로 공간적 그룹으로 분류하였다. 이와 같은 6개의 그룹에 대해서 조류 주의보 이상의 Chl-a 농도에 해당된 월별 자료로 다중회귀분석을 실시하였다. 시 공간적으로 분류된 6개 그룹을 Chl-a 농도와 3개의 기상요인, 11개의 수질 요인 및 유량 요인과의 상관분석을 수행하여, 상관분석결과를 회귀분석의 독립변수로 적용하고. 각 6개의 그룹 별로 Chl-a 농도 예측식을 도출하고자하였다. 위 연구방법으로 수행한 연구 결과는 아래와 같다. 군집분석을 실시한 결과 연 총강수량이 평년수준이었던 평수기그룹(2012~2013년)과 연 총강수량이 1,000mm/hr 미만으로 극심한 가뭄특성을 보였던 가뭄기그룹(2014~2015년)으로 시간적으로 분류되었다. 평수기그룹과 가뭄기그룹 별로 각 3개의 보 지점에서 조류 주의보 이상의 Chl-a 농도에 해당된 월은 평수기그룹은 3~8월이었고, 가뭄기그룹은 3월, 6~10월이었다. 각 6개의 그룹 별로 Chl-a 농도와 기상, 수질 및 유량 등의 요인과의 상관분석을 수행한 결과, 3개의 보 모두에서 평수기그룹보다 가뭄기그룹의 수온 및 유량이 Chl-a 농도와의 상관성이 증가하였다. 이는 극심한 가뭄에 의한 하천 내 유속 감소와 체류시간 증가로 인한 영향으로 판단된다. 6개의 그룹에 대한 상관분석을 수행한 결과에 따라 Chl-a 농도와의 상관성이 큰 기상, 수질 및 유량 요인들을 Chl-a 농도 예측식의 독립변수로 적용하여 다중회귀분석을 수행한 결과에 의하면, 남한강의 하류에 위치하고, 팔당댐과 직접적으로 연결되어 있는 이포보에 대한 Chl-a 농도 예측식의 $Ad.R^2$ 값은 평수기그룹에서 0.920, 가뭄기그룹 0.818로 우수한 선형성을 나타내었다.

Keywords

References

  1. Choi AR, Oh HM, Lee JA. 2002. Ecological study on the toxic microcystis in the lower Nakdong river. The Korean journal of phycology. 17(3): 171-185. [Korean Literature]
  2. GRI(Gyunggi Research Institute). 2012. Four major river after for major river. Issue & Diagnosis, [Korean Literature]
  3. Helnle DR. 1992. Eutrophication of freshwaters, principles, problems and restoration. 2nd ed John Wiley & Sons, Ltd, London.
  4. Jeon SH. 1996. Advanced in-situ sediment remediation technology for lakes and rivers. Korea Environment & Water Works Research Institute. [Korean Literature]
  5. Jeon SH, Park YA. 1989. Forms and mobility of sediment phosphorus in lake Soyang. Korean journal of limnology. 22(3): 261-271. [Korean Literature]
  6. Jo KJ, Shin JG. 1996. Bioassay for N, P nutrient demand by freshwater algae cultivation of the Nakdong river. Korean journal of ecology and environment. 29(4): 263-273. [Korean Literature]
  7. Kang MK, Choi IY, Park JH and Choi JH. 2012. Investigation of the effect of weirs construction in the Han river on the characteristics of sediments. Korean society of environmental engineers. 34(9): 597-603. [Korean Literature] https://doi.org/10.4491/KSEE.2012.34.9.597
  8. Kim DH. 2009. Problems on the restoration of four major rivers project - focus on YeongSan river. Proceedings of the Korean Society for Marine Environment & Energy. The Korean Society for Marine Environment & Energy, 117-122. [Korean Literature]
  9. Kim YY. 2012. A study on prediction model and evaluation of river water quality using multivariate statistical techniques. M.D. dissertation. Kyonggi University. Korea
  10. Kim JS, Jun KS. 2010. Flood level mitigation effect of river dredging. Korean society of civil engineers. 2: 139-146. [Korean Literature]
  11. Kim BC, Kim DS, Hwang KS, Choi KS, Heo WM and Park WK. 1996. Contribution of primary production of phytoplankton to organic pollution in a eutrophic river. the Naktong river. The Korean journal of phycology. 11(2): 231-237. [Korean Literature]
  12. Park CK. 2009. Some problems of the green growth policy and the project saving the four major rivers. Economy and Society. 83(9): 117-14. [Korean Literature]
  13. Shin RY, Park HK, Ryu HS. 2015. Characteristics of cyanobacterial occurrence and correlation analysis with environmental factors in the middle-downstream of Nakdong river. The Joint conference of KSWW & KSWQ, KSWW & KSWQ. 180-180. [Korean Literature]