Evaluation of Water Quality Characteristics Using Multivariate Statistical Analysis in the Fourth Reservoir

Abstract

In this study, multivariate statistical analysis was applied to analyze the trend of water quality and water quality in the Fourth reservoir over the last 10 years. Correlation analysis between water quality variables showed that, the correlation coefficient between COD and TOC, which is an indirect indicator of organic matter, showed a high correlation of 0.608, while water temperature showed a positive correlation with pH of 0.515 and a negative correlation with DO of -0.716. Principal component and factor analyses showed that the four major components were extracted from the total water quality and contributed 72.9% of the total variance. When analyzed for cyanobacteria occurrence, three major components were extracted and contributed 67.2% of the total variance. Factor loadings analysis of water quality variables on the factors identified the first factors as COD and TOC. Water quality of the Fourth reservoir was found to be influenced by seasonal effects such as rainfall and organic matter, in addition to the effects of phytoplankton proliferation and nutrient influx.

Water Quality Analysis and Chl-a Prediction of 15 Large-scale Freshwater Lakes in Korea by Multivariate Statistical Analysis

“…Environ. Eng., 44 (12), 589-602, 2022 https://doi.org/10.4491/KSEE.2022.44.12.589 (NO 3 -N), ammonia nitrogen(NH 4 -N), dissolved total nitrogen (DT-N), total phosphorus(T-P), phosphate-phosphorus(PO 4 -P), dissolved total phosphorus(DT-P), 독립영양식물인 조류의 Chl-a 자료를 수집하여 통계분석에 활용하였다(Table 1). 종합 TSI ko 의 결과를 바탕으로 빈영양(Oligotrophic, TSI ko ≤ 30), 중영양(Mesotrophic, 30<TSI ko ≤50), 부영양(Eutrophic, 50 < TSI ko ≤ 70), 과영양(Hypertrophic, TSI ko >70)의 4단계로 영양상태를 분석하였다.…”

“…11,12) 기존의 농업용수 수질 유형화 방법에서는 유효저수량/만수 면적비(effective storage/water surface, ST/WS)와 부영양화지 수(trophic state index, TSI) 기반 영양상태와 제한 영양염 (algal growth potential, AGP)을 활용한 분류방법 등이 있다. 예를 들어, ST/WS가 큰 것은 상대적으로 저수용량이 크고, 저수지가 깊은 형상으로서 내부생산을 억제할 수 있는 형태인 것으로 판단하는 반면 ST/WS가 작은 것은 수표면적이 크기 때문에 상대적으로 수체 내 광량 유입이 많고, 저수지의 깊이 가 얕으며 저수용량이 적어 부영양화현상이 발생하기 쉬운 형태인 것으로 판단한다 13).…”