우리나라 주요 호소의 수질 변동 경향성 분석 및 유형화

Abstract

In this study, we evaluated the temporal changes of water quality in the 90 reservoirs in Koreaand the relationships between water quality and their environmental factors in the reservoirs for effectivemanagement of reservoirs. The majority of study reservoirs were categorized as the eutrophic state based onCarlson’s trophic index. Among 90 reservoirs, more than 55.0% were nutrient-rich based on TSITP in eachmonth, where more than 50.0% were nutrient-rich based on TSIChl-a from June to November. Seasonal Mann-Kendall test was used to analyze temporal variation of water quality in the selected 60 reservoirs usingmonthly data from 2004 to 2008. The results showed that 27 (45.0%) reservoirs showed the improvement ofwater quality based on TP and Chl-a concentrations, while 14 (23.3%) and 11 (18.3%) reservoirs displayed thedegradation of water quality based on TP and Chl-a concentrations, respectively. Meanwhile, a self-organizingmap classified the study reservoirs into five groups based on differences of hydrogeomorphology (altitude,catchment area, bank height, lake age, etc.). Physicochemical factors and land use/cover types showed cleardifferences among groups. Finally, hydrogeomorphology of reservoirs were related to water quality, indicatingthat the hydrogeomorphological characters strongly affect water quality of reservoirs.