2003년 3월 대조기 광양만 부유퇴적물의 유 · 출입에 관한 연구

Abstract

As a preliminary study on the sediment flux, concentrations of suspended particulate matter and current speeds were measured at three inlets of Gwangyang Bay during one tidal cycle of a spring tide of March 2003. The suspended sediment flux rate <TEX>$(g/m^{2}/s)$</TEX> at the mouth of Seomjin River (St. K1) was observed to be higher throughout surface layer during ebb tide <TEX>$(14.3\;g/m^{2}/s)$</TEX> and throughout near-bottom layer during the flood tide <TEX>$(23.2\;g/m^{2}/s),$</TEX> resulting in a net upstream-ward transport of<TEX>$0.9{\times}10^{3}kg/m$</TEX> during 13 period. At the inlet toward Yeosu Bay (St. K2), a relatively low rate (<TEX>$(5.0-6.7\;g/m^{2}/s)$</TEX> of sediment flux occurred throughout the water column compared to St. K1, with a depth-integrated net transport of <TEX>$5.6{\times}10^{3}kg/m$</TEX> toward the outer reaches of Gwangyang Bay inlet. At St. K3 located at Gwangyang Bay-side of Noryang Strait, the outward flux toward the Jinju Bay was observed to be dominant during the flood tide <TEX>$(16.2-23.2\;g/m^{2}/s)$</TEX>, especially through the mid and near bottom layer, compared to the inward flux throughout the whole water column during the ebb tide <TEX>$(13.1-19.7\;g/m^{2}/s).$</TEX> The net transport at St. K3 was calculated to be <TEX>$4.0{\times}10^{3}kg/m$</TEX> toward the outside of Gwangyang Bay. The outward net transport of suspended sediment at all three inlets seems to be consistent with a trend of bottom sediment texture, which suggests a net movement of sediment from a relatively coarse and poorly sorted inner-bay toward a relatively fine and better sorted outer-bay environment.