DOI QR코드

DOI QR Code

Long-term Prediction of Water Quality in Osaka Bay

  • Published : 2004.11.01

Abstract

As an effort to clarify the ecosystem of Osaka Bay, a semi-enclosed coastal area under the influence of stratification, a three-dimensional water quality model with combination of the baroclinic flow model and primitive eco-system model was constructed. The proposed model succeeded in simulating the time-depending flow and density structure and the baroclinic residual currents in Osaka Bay. In present study, we tried to improve the model by taking account of the benthic-pelagic interaction and exchange of nutrients between sea bottom sediments and overlaying water. On vertical structure, the model consists of 13 layers of water and eight layers of sediments. Long-term prediction of water quality was conducted from 1964 to 1985. This period is characterized by rapid water pollution and its decrease by the cutoff reduction of COD and P flowed into Osaka Bay. By combining the sediment model into original model, the numerical model was confirmed to shows more reasonable results in simulating the water quality in Osaka Bay.

Keywords

References

  1. Larsen, D.P., J. V. Sickle, K. W Malueg and P. L. Smith, 1979, The effect of waste water phosphorus removal on shagawa Lake: phosphorus supply, lake phosphorus and chlorophyll, Water Research, 13, 1259-1272 https://doi.org/10.1016/0043-1354(79)90170-2
  2. Nakatsuji, K. and T. Fujiwara, 1997, Residual Baroclinic Circulations in Semienclosed Coastal Seas, journal of Hydraulic Engineering, 123(4), 362-373 https://doi.org/10.1061/(ASCE)0733-9429(1997)123:4(362)
  3. Nakatsuji, K., J. Huh and Murota, 1991, Numerical experiments of three-dimensional buoyant surface discharge, Proc., Japan Soc. Of Civ. Engrs., Editorial Com. On Tech. Publ, 434, 29-36
  4. Yamane, N., K. Nakatsuji, H. Kurita, and K. Muraoka, 1998, Field data collection and analysis for verification of ecosystem model in semienclosed Osaka Bay, Japan, Proc. 5th Conf. On Estuarine and Coastal Modelling
  5. Joh, H., 1986, Studies on the mechanism of eutrophication and effect of it on fisheries production in Osaka Bay, Bulletin of. Osaka Prefecture fisheries Experimental station(in Japanese), 7, 174
  6. Hosomi, M., and R. Sudo, 1992, Development of the phosphorus dynamic model in sediment-water system and assessment of eutrophication control programs, Water Science and Technology, 26, 158-162
  7. Recknagel, F., M. Hosomi, T. Fukusima and D. Kong, 1995, Short- and long-term control of external and internal phosphorus loads in lakes, Water Research, 29(7), 1767-1779 https://doi.org/10.1016/0043-1354(94)00318-2
  8. Horie, T. and Y. Hosokawa, 1984, Modeling on the behaviors of phosphorus in sea bed, Report of the port and harbour research institue, 23(2), 25-37