• 한국농공학회논문집
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• 제54권2호
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• pp.27-35
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• 2012

Various Best Management Practices (BMPs) have been suggested to reduce Nonpoint source pollutant loads from agricultural fields. However, very little research regarding water quality improvement with sediment trap has been performed in Korea. Thus, effects of sediment trap were investigated in this study. Three sediment traps were installed at the edge of six plots and flow and water quality of inflow and outflow were monitored and analyzed. It was found that approximately 64.1 % of flow reduction was observed. In addition, pollutant concentration of outflow was reduced by 39.0 % for $BOD_5$. For SS, $COD_{Mn}$, DOC, T-N, T-P, approximately 62.1 %, 43.4 %, 43.5 %, 40.0 %, and 41.2 % reduction were observed, respectively. Over 80 % and 90 % of pollutant loads were reduced from sediment trap #2 and #3 because of less outflow from plots covered with rice straw/straw mat. In case of intensive rainfall events occurred from July 26~29, 2011, over 60 % of pollutant and 88.9 % of sediment reduction were observed from sediment trap #3. As shown in this study, small sediment traps could play important roles in reducing pollutant loads from agricultural fields. If proper management practices, such as rice straw/straw mat, are used to protect surface from rainfall impacts and rill formation, much pollutant reduction could be expected.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.984-993
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• 1993

land application of sewage sludge requires careful monitoring because of its potential for contamination of surface water and groundwater. A rainfall simulator was used to investigated the effects of freshly applied sludge on runoff of sediment and nutrients from agricultural crop lands. Rain was applied to 16 experimental field plots. A three run sequence was used to simulate different initial moisture conditions. Runoff, sediment and nutrient losses were monitored at the base of each plot during the simulated rainfall events. Sludge was surface applied and incorporated at conventionally -tilled plots and surface applied at no-till plots, at rates of 0, 75, 150 kg-N/ha. No-till practices greatly reduced runoff, sediment , and nutrient losses form the sludge treated plots, relative to the conventional tillage practices. Incorporation of the sludge was effective in reducing nutrient yields at the conventionally-tilled plots. This effect was more pronounced during the third rain torm, with wet initial conditions. Peak loadings of nutrients appeared during the rainstorm with wet initial conditions.

• 환경영향평가
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• 제18권6호
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• pp.435-443
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• 2009

Ba Ria - Vung Tau province in Southern Vietnam is one of the fastest economic growing areas in the country, characterized by the rapid port and industrial development along the Thi Vai river. The socio-economic situation of the area has generally been improved; however, its part of the local inhabitants has not gained benefits from the changes. 35 surface water samples and 25 sediment samples were analysed with the interpretation of the SPOT images for 1995 and 2005. The data showed that rapid port and industrial development have resulted in significant losses of mangroves and agriculture land. The surface water was seriously polluted, particularly in terms of organic materials and suspended solids. It contained high and increasing oil concentrations. The river sediment was saline and slightly alkaline. It was heavily reduced, organic-rich, and contaminated with oil and heavy metals (Cu, Pb, and Cr).

• 한국수산과학회지
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• 제46권6호
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• pp.930-940
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• 2013

We evaluated contamination with organic matter and trace metals by analyzing grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Ni, Cr, Mn, Hg, and As) in surface sediments at 28 stations around the Geum River estuary in July 2008. The surface sediments in the estuary were mainly composed of coarse sediment (sand and muddy sand), with mean grain size (Mz) ranging between $2-4{\O}$. The high concentrations of IL, COD, and trace metals were mainly found at stations in front of the Gusan outer port and industrial complex, and near the Seocheon coast with relatively fine sediments. In addition, the concentrations of IL and all trace metals, except Pb and As, showed good positive correlations with Mz, indicating that the concentrations of organic matter and trace metals were mainly dependent on sediment grain size. The concentrations of COD, AVS, and trace metals in most sediments did not exceed the sediment quality guideline (SQGs). Although the sediments in the study region are not polluted with organic matter and trace metals, there are many point sources of pollutants, such as Gusan port and industrial complex, Janghang refinery, and a thermoelectric power plant around the Geum River estuary. Thus, the management of coastal environments through periodic monitoring of organic matter and trace metals is required in the future.

• 대한토목학회논문집
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• 제26권1D호
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• pp.141-147
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• 2006

강우에 의해서 발생하는 토양유실은 비옥한 표토를 유실시켜 생산성의 저하를 초래하고, 유실된 토양입자는 하천이나 호수, 댐 등에 퇴적되어 저수용량의 감소와 수질관리에 어려움을 야기 시키므로 이에 대한 대처가 필요하다. 본 연구에서는 위성 영상과 GIS 기법을 활용하여 유역내 토양침식에 영향을 미치는 토양조건, 피복조건, 지형조건들을 추출하고 이 요소들을 범용토양유실공식(USLE; Universal Soil Loss Equation)에 적용하여 유입퇴적량 및 유입 가능성이 높은 위치를 파악하였다. 또한 유입되어 하상에 쌓여 있는 퇴적량은 투과성이 강한 음향측심기를 활용하여 퇴적층과 지층의 고도 정보를 획득하여 산정하고 유실량과 퇴적량을 비교하여 퇴적되는 비율을 도출하였다.

• Ocean and Polar Research
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• 제35권3호
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• pp.229-237
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• 2013

We measured two-dimensional (2-D) oxygen distribution in the surface sediment layer of intertidal sediment using a simple and inexpensive planar oxygen optode, which is based on a color ratiometric image approach. The recorded emission intensity of red color luminophore light significantly changed with oxygen concentration by $O_2$ quenching of platinum(II)octaethylporphyrin (PtOEP). The ratios between the intensity of red and green emissions with oxygen concentration variation demonstrated the Stern-Volmer relationship. The 2-D oxygen distribution image showed microtopographic structure, diffusivity boundary layer and burrow in surface sediment layer. The oxygen penetration depth (OPD) was about 2 mm and the one-dimensional vertical diffusive oxygen uptake (DOU) was 12.6 mmol $m^{-2}d^{-1}$ in the undisturbed surface sediment layer. However, those were enhanced near burrow by benthic fauna, and the OPD was two times deeper and DOU was increased by 34%. The simple and inexpensive oxygen planar optode has great application potential in the study of oxygen dynamics with high spatiotemporal resolution, in benthic boundary layers.

• 한국습지학회지
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• 제7권2호
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• pp.53-67
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• 2005

천수만은 전형적인 반 폐쇄형만으로 수로, 사퇴, 작은 섬 그리고 갯벌 등 다양한 환경들이 있다. 1983년에서 1985년 사이에 건설된 서산 A와 B 방조제는 천수만 북부의 퇴적환경을 지속적으로 변화시켰을 것으로 보인다. 황도 갯벌과 주변 해역의 퇴적환경을 파악하기 위하여 2003년 6월과 10월에 표층과 주상 퇴적물을 채취하였다. 표층 퇴적물은 5개의 퇴적상으로 구성되어 있었다. 일반적으로 10월의 표층퇴적물은 6월과 비교하여 갯벌은 조립해 졌으나 주변 해역은 거의 변화가 없었다. 3개의 주상퇴적물의 퇴적상은 황도 주변 갯벌은 파랑과 조류 에너지가 상대적으로 높고, 조수로 근처의 갯벌은 에너지가 상대적으로 낮은 것으로 나타났다. 황도 갯벌의 11개월 동안 단기 퇴적률은 중앙지역은 퇴적 되었으나, 갯벌의 동쪽 측면과 서쪽 측면은 침식된 것으로 나타났다. 이는 방조제에 의하여 조류 형태와 퇴적물 순환이 변화되었기 때문으로 보인다.

• 한국환경과학회지
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• 제8권5호
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• pp.593-600
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• 1999

In order to determine the changes of sediment facies and metal levels in surface sediments after the construction of Shiwha Lake, surface sediments were sampled at 8 sites located on the main channel monthly from June, 1995 to August, 1996 and analysed for 12 metals (Al, Fe, Mn, V, Cr, Co, Ni, Cu, Zn, Cd, As and Pb) by ICP/AES and ICP/MS. Two groups of sampling sites(the inner lake with 3 sites and the outer lake with 5 sites) are subdivided by the surface morphology ; the inner lake is a shallow channel area with a gentle slope, while the outer lake is relatively deep and wide channel with a steep slope which has many small distributaries. After the construction of dam, fine terrestrial materials were deposited near the outer lake, which resulted in the change of major sediment facies from sandy silt to mud. With the deposition of fine sediments in the outer lake, anoxic water column induced the formation of sulfide compounds with Cu, Cd, Zn and part of Pb. Metal (Cr, Ni, Cu, Zn and Cd) contents in sediments increased up to twice within 2 years after the construction of dam. This is due to the direct input of industrial and municipal wastes into the lake and the accumulation of metals within the lake. In addition, frequent resuspension of contaminated sediments in a shallow part of the lake may make metal-enriched materials transport near the outer lake with fine terrestrial materials. As the enrichment of Cu, Zn, Cd and part of Pb in the Shiwha Lake may be related to the formation of unstable sulfide compounds by sulfate reduction in anoxic water or sediment column, the effect of mixing with open coastal seawater is discussed.

• 한국수자원학회논문집
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• 제49권1호
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• pp.73-81
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• 2016

본 연구에서는 식생에 의한 하도 변화와 하상토 분급특성을 파악하였다. 유사의 유출 특성은 불규칙하며, 식생 밀도가 증가함에 따라 유출되는 유사량은 감소하였다. 하상고는 불규칙하게 변하며, 하상토 표층에서 유사 입경은 작아졌다. 식생 밀도가 증가함에 따라 하상 표층에서 무차원 중 앙입경의 비는 감소하였다. 식생대에서 유사가 포착되거나, 식생대와 주흐름 사이에 경계층 흐름이 발생하여 유사가 퇴적되며, 식생대에서 흐름의 방향이 변화되어 표층에서 하상토 입도는 불규칙하게 분포하였다. 무차원 하상토 입경이 감소함에 따라, 차폐효과는 일정하게 감소하였다. 식생밀도가 증가함에 따라 하상 표층에서 차폐효과가 증가하며, 이것은 실험 수로 하류단에서 유사 유출량이 감소하는 것과 일치한다. 식생 밀도가 $0.5stems/cm^2$에서 저수로 이동은 감소하고 안정적인 특성을 보여주었으나, $0.7stems/cm^2$에서 저수로 이동은 증가하였다. 이것은 식생 밀도가 증가하면서 저수로 사행도가 증가하고, 식생대에서 유사가 퇴적되어 새로운 저수로가 형성되었기 때문이다.

• 해양환경안전학회지
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• 제26권4호
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• pp.392-402
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• 2020

살포식 패류양식해역인 진주만의 퇴적물 중 유기물과 금속의 분포 특성 및 오염상태를 파악하기 위하여 2015년 8월에 산휘발성황화물(AVS), 강열감량(IL), 총유기탄소(TOC), 총질소(TN), 금속원소(As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Zn)를 조사하였다. 퇴적물 중 유기물과 금속원소의 농도는 패류양식장이 밀집해 있는 만의 남쪽 해역에서 높고, 우리나라 남해안의 다른 해역과 비슷하거나 낮았다. C/N비(5.7~8.0)를 기초로, 진주만 퇴적물의 유기물은 해역 자체에서 생성된 해양기원성인 것으로 파악되었다. 퇴적물 오염평가 결과, 유기물(AVS, TOC)과 금속원소(As, Cd, Cr, Cu, Hg, Pb, Zn) 농도는 우리나라의 퇴적물 기준보다도 상당히 낮았다. 또한, 금속원소 전체 농도를 고려한 오염부하량지수(PLI)와 생태계위해도지수(ERI) 결과는 패류 양식장이 밀집해 있는 남쪽 해역에서 높은 오염도를 보이지만, 대부분의 해역에서 저서생물에 약간 부정적인 생태 영향을 줄 수 있는 오염 상태였다. 그러므로, 진주만 퇴적물은 현재 유기물에 대해서는 오염되지 않았고, 금속원소에 있어서는 약간 오염된 상태인 것으로 파악되었다.