• Ocean and Polar Research
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• 제30권4호
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• pp.379-399
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• 2008

Spatial-temporal variations in physiochemical water qualities (temperature, salinity, DO, SPM, POC and nutrients) of surface and bottom waters were investigated along the mid-western coastal area (Taean Peninsula to Gomso Bay) of Korea. Spatial distribution patterns of temperature and salinity were mostly controlled by the physical mixing process of freshwater from Geum River and/or Gyunggi Bay with nearby coastal water. A strong tidal front is formed off Taean Peninsula during spring and summer. Seasonal variations in nutrient concentrations, lower in spring and summer and higher in fall and winter, are primarily regulated by magnitude of phytoplankton occurrence rather than freshwater loadings into the bay. Based on seasonal and spatial variability of physicochemical parameters, water quality of the study area can be divided into four water masses; Gyunggi Bay-influenced Water Mass (GBWM), Geum River-influenced Water Mass (GRWM), Yellow Sea Bottom Cold Water Mass (YSBCWM) and Cheonsu Bay Water Mass (CBWM). Water quality of the GBWM (Taean Peninsula coastal area), which has relatively low salinity and high concentrations of nutrients, is strongly controlled by the Gyunggi Bay coastal water, which is under influence of the Han River freshwater. In this water mass, the mixed layer is always developed by strong tidal mixing. As a result, a tidal front is formed along the offshore boundary of the mixed layer. Such tidal fronts probably play an important role in the distribution of phytoplankton communities, SPM and nutrients. The GRWM, with low salinity and high nutrients, especially during the flood summer season, is closely related to physiochemical properties of the Geum River. During the flood season, nutrient-enriched Geum River water mass extends up to 60 km away from the river mouth, potentially causing serious environmental problems such as eutrophication and unusual and/or noxious algal blooms. Offshore (<$30{\sim}40m$ in water depth) of the study area, YSBCWM coupled with a strong thermocline can be identified in spring-summer periods, exhibiting abundant nutrients in association with low temperature and limited biological activity. During spring and summer, a tidal front is formed in a transition zone between the coastal water mass and bottom cold water mass in the Yellow Sea, resulting in intensified upwelling and thereby supplying abundant nutrients to the GBWM and GRWM. Such cold bottom water mass and tidal front formation seems to play an important role in controlling water quality and further regulating physical ecosystem processes along mid-western Korean coastal area.

• 한국토양비료학회지
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• 제42권6호
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• pp.447-453
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• 2009

간척지에서 식생의 분포와 토양 염농도 간의 관계를 분석하기 위하여, 간척 후 교란이 없는 대호 간척지의 식생보전지구에서 본 연구를 수행하였다. 출현 식물 종을 분류하고, 집락 유형별로 토양 염농도를 측정하여 비교하였고, 식생도를 작성하였다. 대호 간척지의 식물 종은 주기적인 침수가 이루어지는 갯벌 및 초기 간척지에 비해 매우 다양하였다. 출현한 식물 집락은 단일 종으로 이루어진 순수 집락과 여러 종의 혼합으로 이루어진 혼생 집락으로 구분되었다. 식물 집락별 출현지의 토양 염농도에 근거할 때 퉁퉁마디, 해홍나물 및 나문재의 단일 집락은 토양 염농도가 31.05 dS/m 정도인 곳에, 이들의 혼생 집락은 42.75 dS/m에 출현하여 내염성이 강하였고, 사데풀, 갯개미취, 새섬매자기 등의 단일집락은 11.73 dS/m 인 곳에, 이들의 혼생집락은 9.43 dS/m 정도인 곳에 출현하여 저염생식물군의 특성을 보였고, 띠, 레드클로버, 억새, 강아지풀 및 잠자리피의 단일집락은 2.42 dS/m 정도인 곳에 분포하여 내염성이 약한 중성식물군의 특성을 보였다. 이와 같이 식물 집락의 분포는 토양 염농도의 영향을 받고 있어, 간척지 토양의 염농도는 식물 집락 분포의 제한요소로 작용함을 보였다. 이 결과는 토양 염농도에 따라 다르게 나타나는 식물 종과 식물 집락의 분포 양상이 간척지 토양의 탈염화 지표로 유용함을 시사하고 있다.