earticle

영어

The QUAL2E model has been widely used to predict water quality, but it doesn`t regard the changes(variations) of dissolved oxygen by a water plant or sticking algae and also BOD by floating algal death. Also, it doesn't regard the denitrification reaction and organic substances originated from dead algae, either. Thus it has a limitation to applicate for rivers which are influenced a lot by these changes. To solve these problems, QUALKO model is, therefore, developed in Korea.
The purpose of this study is to make a comparative study on water quality prediction results by QUAL2E and QUALKO in Youngsan water system, and the results are as follows. When same coefficients in both QUAL2E and QUALKO are applied, The prediction results of BOD, T-P and T-N are good in both models. In QUAL2E model, the average values of R2 in calibration are 0.935, 0.765, 0.817 in BOD, T-N and T-P, respectively, and the cases of R2 in verification are 0.776, 0.856, 0.698, respectively. In QUALKO model, the average values of R2 in calibration are 0.945, 0.763, 0.821 in BOD, T-N and T-P, respectively, and the cases of R2 in verification are 0.787, 0.855, 0.685, respectively. These results show the possibility of QUALKO Model as a alternate when the number of calculation elements and a pollution sources etc exceeds the input limit of QUAL2E model. Because the QUALKO model is known as a good mnput limsystem in stagnated waters which has high algal growth, further research is necessary about the application of impounded watermsystems such as the downstream of Yeongsan river.