• 한국해양공학회지
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• 제28권3호
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• pp.236-244
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• 2014

This study considered a seagrass habitat in order to analyze the characteristics of a marine environment of seagrass located in the Seomjin river estuary, through an analysis of the distribution of the water depth, field observation, and three-dimensional numerical experiments using an EFDC model. The seagrass habitat was usually distributed at D.L(-) 0.5~0.0 m, and was hardly seen in the intertidal zone higher than that range. The distribution of the water temperature was within the range of $7.0{\sim}23.2^{\circ}C$, and the seagrass was demonstrated to have a strong tolerance to changes in the water temperature. In addition, the salinity distribution was found to be 27.2~31.0 psu, with suspended solids of 32.1 mg/L, which were higher than the previous research results (Huh et al., 1998), implying that there may be a reduction in the amount of deposits caused by the suspended solids. As for the sedimentary facies, they were comprised of 62.7% sand, 19.1% silt, and 18.2% clay, indicating that the arenaceous was superior and the sedimentary facies were similar to that of Dadae Bay. According to a numerical experiment, the maximum tidal current was 75 cm/s, while the tidal residual current was 10 cm/s, confirming that it sufficiently adapted to strong tidal currents. The erosion and deposition are predicted to be less than 1.0 cm/year. Thus, it is judged that the resuspension of sediments due to tidal currents and the changes in sedimentary facies are insignificant.

• 한국지반신소재학회논문집
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• 제12권4호
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• pp.21-33
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• 2013

본 연구에서는 FNS의 공학적 특성을 평가하고, 소형 및 대형 모형토조를 통하여 원지반과 유사한 조건으로 FNS 매립시에 주변토양에 미치는 환경적 영향을 평가하고자 하였다. 주입액은 담수, 산성, 해수를 사용하였으며 모래와 실트시료를 사용하여 각각 상대밀도(40%, 60%)와 다짐도(90%) 조건을 선정하여 실험하였다. 소형 및 대형 모형토조에서 배출되는 용출액은 pH 분석을 실시하였으며, 주입이 완료된 후에 샘플을 추출하여 토양오염분석을 수행하였다. 그 결과, 모래보다 실트에서 pH의 오염도가 더 높게 나타남을 확인할 수 있었고, FNS가 주변 토양에 미치는 환경적 영향은 미미한 것으로 나타나 향후 천연골재 대체재로 활용 가능할 것으로 판단된다.

• 대한환경공학회지
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• 제32권1호
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• pp.9-16
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• 2010

하구 간석 퇴적 유기물의 기원과 계절적 변동 특성을 해명하는 것을 목적으로, 나나키타강 하구 갯벌의 세립토 함유율(<63 ${\mu}m$), Chl.a, TOC, C/N비 및 탄소 질소 안정동위원소 비(${\delta}^{13}C$, ${\delta}^{15}N$)를 측정했다. 그 결과, 모래질 갯벌에서는 해양성 기원 유기물과 부착 조류의 영향이 큰 것으로 밝혀졌다. 반면, 진흙질 갯벌에서는 육지 기원 유기물의 영향이 컸다. 게다가 퇴적물중의 유기물량과 유기물의 기원은 계절에 따라 변동 하는 것이 분명하고, 그 요인으로서는, 모래질 갯벌에서는 부착 조류와 고조(高潮) 및 월파(越波)에 의한 퇴적이 주요인이었으며, 진흙질 갯벌에서는 육상에서의 유기물의 유출에 의한 퇴적이 특징적이었다.

• 한국토양비료학회지
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• 제25권3호
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• pp.213-219
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• 1992

충북(忠北) 괴산군(槐山郡)에 위치한 옥천계(沃川系) 천매암토양(千枚岩土壤)의 특성을 사면경사(斜面傾斜)에 따라 토양(土壤) catena를 구명하고, 옥천계토양(沃川系土壤)의 분포를 조사하고자 수행하였다. 1. 옥천계모암(沃川系母岩)은 216천ha 분포하였으며, 옥천계토양(沃川系土壤)은 목(目) 2 아목(亞目) 3 대군(大群) 4 아군(亞群) 5 토양통(土壤統) 9개로 밝혀졌다. 2. 사면경사(斜面傾斜)는 토색연속계(土色連續系)를 이루었으며, 토색지수와 $Fe_2O_3$ 함량은 배수가 양호할 수록 증가하였다. 3. 미사/점토비(比)와 Ca/Mg比는 상대표고(相對標高)가 높을 수록 그리고 토심이 깊을 수록 좁아졌다. 4. 토양의 생성년령은 산견(山肩)>산복(山腹)>산록(山麓)>산지경사(山肢傾斜), 토양모재의 생선년령은 C>B>A층의 순이었다. 5. 토양단면내 토색지수와 $Fe_2O_3$ 함량은 고도의 유의성을 나타내었다. 6. 생성학적 유형은 C/D형이었으며, 토심>12cm에서의 토양성질 변화는 연속함수(連續函數)를 갖는다.

• 한국환경복원기술학회지
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• 제11권5호
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• pp.60-71
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• 2008

Through analyzing the specific physicochemical alterations in depth-based soil at reclaimed dredging area, the baseline data were provided for developing the reclaimed dredging area as natural landscape planting sites and ecological-landscape sites based on the soil improvement technology. There was no physical disturbance for 15 to 20 years in Gwangyang Bay reclaimed dredging area after reclamation. Physicochemical examinations of the soil were performed based on the vertical depth. Results of physicochemical analysis such as pH, electric conductivity, total salt contents, silt, clay contents, available phosphorus, calcium, magnesium, sodium, chlorine, and sodium-adsorption ratio showed increasing patterns with the depth while total organic contents, total nitrogen, and sand showed decreasing patterns. Potassium as an exchangeable cation, showed similar distribution patterns between the shallow and deep soil. This result strongly implied that long-term exposure to natural rainfall in reclaimed dredging area altered soil characteristics related to salinity. This research demonstrated that there were no remarkable differences in physicochemical characteristics at soil depth and groundwater table height, suggesting a baseline data for developing reclaimed dredging area. Additional investigation is required for different reclaimed dredging areas. Also, additional monitoring and examination are need on plant communities and time variable alteration in the soil to test the feasibility of reclaimed dredging areas as natural landscape planting sites and ecological-landscape sites.

• 한국수산과학회지
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• 제36권4호
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• pp.402-408
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• 2003

A quantitative method was suggested for estimating damages in fishery production due to the diffusion and deposition of suspended silt and clay by various construction processes in tidal flat fishing grounds. Marine populations are maintained through the process of spawning, growth, recruitment, natural death and death by fishing each year. All of the year classes of the population in a fishery ground could be affected when damages occur by human activities such as land filling or reclamation. The propose of this study is to calculate damages in terms of fishery production using a quantitative population dynamic method. If the maximum age in the population is $X_\lambda,$ the starting year of damage is $t_s,$ and the ending year of damage is $t_e,$ the number of year classes damaged is $t_{s-n\lambda}-t_e,$ Many year classes present in the year $t_s,$ and so if damages occur, they Influence all the year classes which are present in the population. Damaged year classes in year $t_e$ would still be in the population until the year $t_{e+n\lambda}$, where $n_{\lambda}$ is the oldest age class. If the expected yield of a year class is constant, the total yield from year classes in the fishing ground during the construction periods can be calculated as follows: $Y_\Phi=[(t_e-t_s+1)+n_c]{\cdot}Y_E+\sum\limits^{n_\lambda-n_c}_{l=1}\;\sum\limits^{n_\lambda-n_c}_{l=i}\;Y_{n_c+i}$ This method was applied for damage estimation in the production of Ruditapes philippinarum in a tidal flat fishing ground.

• 한국환경과학회지
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• 제10권5호
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• pp.315-321
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• 2001

This study was conducted to estimate the decomposition capacity for organic matter by microbe of tidal flat sediments (Hajae, Dongjin and Mankyung). The decomposition rate constants (K') have been determined by Thomas slope method and compared with the values of each tidal flats. The decomposition rates of organic matter by microbe were initially very slow, but at the end of 12 hours, very sharply increased. The values of decomposition rate constant for Dongjin, Mankyung and Hajae tidal flat sediment were 1.364$day^{-1}$/, 1.080d$day^{-1}$ and 0.735$day^{-1}$, respectively. The decomposition rate constant of Dongjin tidal flat sediment which affected by livestock wastewater was higher than others. The decomposition quantity (mg/g/day) of organic matter by microbe of tidal flat sediments was 0.4mg/g/day for Dongjin, 0.36mg/g/day for Mankyung and 0.36mg/g/day for Hajae. The average of decomposition quantity was 0.37mg/g/day. To calculate purification capacity (kg/ha) of organic matter by microbe, we applied to two assumption ; 1) biological action by microbe is occur within 0.1cm under surface 2) specific gravity of sediment are 2.5g/$\textrm{cm}^2$. The purification capacity of organic matter by microbe of tidal flat sediment was calculated to 9.25kg/ha. The relationships between decomposition rate constant (K') and ignition loss (I. L), chemical oxygen demand by sediment (CO $D_{sed}$), total carbon(TC), silt and clay as index of organic matter were a high positive($R^2$=0.97~1.00).

• Ocean and Polar Research
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• 제36권3호
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• pp.209-223
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• 2014

The community structure of benthic meiofauna was investigated from seasonal surveys at seventeen stations off the Saemangeum area, in 2007. Ten meiofaunal taxa were identified. Nematodes were the dominant faunal group in all seasons and harpacticoids were dominant only at a few stations. The mean density of meiofauna was 383 indiv. $10cm^{-2}$, highest in May and November (434 indiv. $10cm^{-2}$), lowest in February (284 indiv. $10cm^{-2}$). Meiofaunal mean biomass was $80.49{\mu}gC{\cdot}10cm^{-2}$, highest in November ($99.54{\mu}gC{\cdot}10cm^{-2}$), lowest in February ($51.56{\mu}gC{\cdot}10cm^{-2}$). Cluster analysis revealed that the study area was composed of three benthic meiofaunal communities. There were significant correlations between major meiofaunal groups and sediment composition and the concentrations of heavy metals. The abundance of harpacticoids are positively correlated with silt (0.559, p < 0.01) and clay (0.340, p < 0.01), and negatively correlated with sand (-0.548, p < 0.01). Harpacticoids also showed positive correlations with heavy metals. The community structure of meiofauna in the study area varied seasonally in response to the change of sediment composition.

• 한국제4기학회지
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• 제3권1호
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• pp.35-45
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• 1989

한국과 서부 유럽의 사질층에 발달해 있는 $B_t$ band의 성인은 퇴적학적인 현상과는 무관하다. 그렇다고 토양학적인 사고만으로도 설명될 수 없다. 본 연구 결과 $B_t$ band는 사질층이 형성된 후 시기를 달리하여 다음과 같이 두 부류의 물질이 서로 다른 메카니즘에 의해 이동.집적되어 형성되었다. 1)먼저 silt중심의 heterometric fine grains과 운모류들이 결빙과 관련된 cryophoresis에 의해 이동되어 이들이 사질층 단면에서 밴드 형태로 집적되었고 2)다음에 철분을 함유한 점토가 토양수에 의해 이미 형성된 맨드에 집적되어 결국 적색의 $B_t$ band가 형성되었다. 이 두 과정에서 전자는 토양의 결빙이 지표에서 3m 정도 이상까지 진전될 정도로 한랭하고 습윤한 환경과, 후자는 podzolization이 진행되는 정도의 냉량.습윤한 환경과 관련된다. 오늘날 갈색토화작용(brunification)이 진전되는 우리나라와 서부 유럽의 경우, $B_t$ band의 polygenetic한 성인과 관련된 한랭.습윤한 환경들은 제4기 근자(주로 Wurm빙기 이래)의 고환경으로 추정된다.

• 한국토양비료학회지
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• 제18권3호
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• pp.276-281
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• 1985

배수연쇄(排水連鎖)에 따른 세립질(細粒質) 화강암(花崗岩)의 풍화(風化) 모재물(母材物)에 기인(基因)된 식양질(植壤質)인 송정통(松汀統)(잔적토(殘積土)), 대곡통(大谷統)(곡간충적붕적토(谷間沖積崩積土)), 지산(芝山) 및 옥천통(玉泉統)(곡간충적토(谷間沖積土))의 형태적(形態的) 이화학적(理化學的) 특성(特性)을 조사연구(調査硏究)한 결과(結果)는 1. 이들 토양(土壤)은 연쇄성(連鎖性)(Catena)이 인정(認定)되며 또한 지형(地形) 지하수위(地下水位) 및 활성철함량(活性鐵含量) 때문에 토색연쇄(土色連鎖)(Soil color sequence)를 가진다. 2. 배수(排水)가 불량(不良)할 수록 미사(微砂)/점토율(粘土率), 토양산도(土壤酸度), 유기물(有機物) 및 유효인산함량(有效燐酸含量)은 증가(增加)하였으나 활성철함량(活性鐵含量)은 그 반대(反對)인 경향(傾向)이었다.