| Title |
Seasonal and long - term trend of water quality in Lake Paldang |
| Authors |
김종민(Jong Min Kim),허성남(Seong Nam Heo),노혜란(Hye Ran Noh),양희정(Hee Jeong Yang),임연택(Yeon Taek Lim),정완종(Wan Jong Jeong) |
| Abstract |
The long-term data (`88∼2000), which have been released by National Institute of Environmental Research (NIER) and Ministry of Construction and Transportation on the water quality and hydrological characteristics in Lake Paldang, were analyzed to find their monthly and annual variation tendency. Water volume tended to decrease during summer season, this phenomenon was assumed that dam authority might open the floodgate in advance to prevent an inundation. And DO saturation ratio exceeded 95% during ail seasons. That time, the concentration of chlorophyll-a (about 10㎎/㎥or higher) and T-P (about 0.03 ㎎/l or higher) denoted high level. Correlation between conductivity and COD denoted middle level (r=0.597, r²=0.36, p$lt;0.01). Conductivity denoted the minimum value in January and February, that was the coldest and freezing season in Lake Paldang. COD denoted the maximum value in June, whereas the inflow and pollutant load were high in July and August. Therefore It was assumed that the effect of dilution was stronger than that of pollutant load. T-N annual variation pattern of annual mean level was similar to COD pattern, but T-P denoted an opposite pattern to T-N. N:P mass ratio seemed to be more affected by T-P concentration than T-N. Annual mean level of N:P mass ratio tended to increased during 1991-2000. In June, transparency denoted the highest level and the concentration of chlorophyll-a & suspended solids denoted the lowest level. The relationship between transparency and suspended solids were relatively high (r=-0.6, r²=0.362, p$lt;0.01) than the relationship between transparency and chlorophyll-a (r=-0.269, r²=0.072, p$lt;0.01). |