• Journal of Ecology and Environment
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• 제30권1호
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• pp.81-86
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• 2007

Human activities have enhanced the influx of heavy metals to aquatic ecosystem and hanged the abiotic environment such as the sediments supporting benthic organisms. The levels of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the benthic gastropod Oxyloma hirasei and the sediments around their habitat were investigated to examine heavy metal levels and the potential of the gastropod as a bioindicator. We detected different levels of heavy metals in the sediments of two wetland areas, Upo and Mokpo, in the relatively well-conserved Upo wetland, Ramsar Convention Area. Oxyloma hirasei had higher concentrations of heavy metals except Cr and Ni in their soft tissues than in their shells (Cd: $2.10{\sim}3.16$, Cu: $19.73{\sim}28.66$, Pb: $0.67{\sim}1.17$, Zn: $216.1{\sim}285.7\;{\mu}g/g$ dry weight in the soft tissues; Cr: $1.19{\sim}2.58$, Ni: $0.47{\sim}1.16\;{\mu}g/g$ dry weight in the shells). Differences in the Cd, Cu, Ni and Pb concentrations in O. hirasei soft tissues reflected differences in heavy metal concentrations in the sediments at the sampling sites. The coefficients of variation for Cd, Cu and Pb were lower than those for other metals in the soft tissues. Levels of Cd in the tissues of O. hirasei were the highest among the metals examined in this study. Therefore, the soft tissue of O. hirasei appears to be a promising bioindicator particularly for Cd.

• 환경정책연구
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• 제9권1호
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• pp.137-154
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• 2010

본 연구는 청주시와 충주시를 대상으로 도시녹지(가로수 및 도시공원)에 의한 중금속 및 누적이산화탄소 고정량을 산출한 결과를 토대로 도시녹지의 환경개선효과를 평가하고자 하였으며, 얻은 결과는 다음과 같다. 1. 청주시와 충주시 가로수 전체에 대한 누적이산화탄소 고정량을 산출한 결과, 청주시의 총량은 약1,230,000kg-C로, 충주시는 약 1,270,000kg-C로 산출되었다. 청주시 발산공원과, 충주시 대가미체육공원에 누적이산화탄소 고정량을 산출한 결과, 청주시 발산공원의 총량은 약 25,000kg-C로, 충주시 대가미체육공원은 약 6,400kg-C로산출되었다. 2. 청주시 가로수에 가장 많이 축적된 중금속은 Zn이었으며, 가장 적게 축적된 중금속은 Ni이었다. 청주시 가로수를 대상으로 중금속을 측정한 결과 Zn > Cu > Cr > Ni > 순으로 나타났다.. 청주시 용도지역별 가로수의 중금속총함량은 주거지역(157.26 mg/kg) > 공업지역(141.71 mg/kg) > 상업지역(118.55 mg/kg) > 녹지지역(61.95 mg/kg)의 순으로 나타났다. 3. 대체적으로 충주시는 청주시보다 모든 항목에서 낮은 함량을 보였는데 이는 도시규모와 교통량의 차이에 따른 대기오염물질 발생량이 다르기 때문이다. 용도지역별 가로수의 중금속 총함량은 상업지역(84.48 mg/kg) > 주거지역(83.70 mg/kg) > 녹지지역(48.23 mg/kg)의 순으로 나타났다. 4. 청주시 용도지역별 가로수 식재지 토양의 중금속 함량은 Zn > Cu > Pb( > Ni > Cr > As > Cd)의 순으로 Zn이 가장 높게 나타났으며, Cd가 가장 낮게 축적된 것으로 분석되었다. 용도지역별 가로수 식재지 토양의 총 중금속 총 함량은 상업지역(91.82mg/kg) > 공업지역(85.96mg/kg) > 주거지역(67.55mg/kg) > 녹지지역(43.13mg/kg)의 순으로 나타났다. 5. 충주시 용도지역별 가로수 식재지 토양의 중금속 함량은 Zn > Pb > Cu( > Ni > Cr > As > Cd)의 순으로 Zn이 가장 높게 나타나 청주시와 유사한 경향을 보였다. 용도지역별 가로수 식재지 토양의 중금속 총함량은 상업지역(87.66mg/kg) > 녹지지역(72.73mg/kg) $${\geq_-}$$ 주거지역(70.10mg/kg)의 순으로 나타났다.

• 한국분말재료학회지
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• 제26권1호
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• pp.6-10
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• 2019

In this study, freeze drying of a porous Ni with unidirectionally aligned pore channels is accomplished by using a NiO powder and camphene. Camphene slurries with NiO content of 5 and 10 vol% are prepared by mixing them with a small amount of dispersant at $50^{\circ}C$. Freezing of a slurry is performed at $-25^{\circ}C$ while the growth direction of the camphene is unidirectionally controlled. Pores are generated subsequently by sublimation of the camphene during drying in air for 48 h. The green bodies are hydrogen-reduced at $400^{\circ}C$ and then sintered at $800^{\circ}C$ and $900^{\circ}C$ for 1 h. X-ray diffraction analysis reveals that the NiO powder is completely converted to the Ni phase without any reaction phases. The sintered samples show large pores that align parallel pores in the camphene growth direction as well as small pores in the internal walls of large pores. The size of large and small pores decreases with increasing powder content from 5 to 10 vol%. The influence of powder content on the pore structure is explained by the degree of powder rearrangement in slurry and the accumulation behavior of powders in the interdendritic spaces of solidified camphene.

• Fisheries and Aquatic Sciences
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• 제27권2호
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• pp.66-75
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• 2024

Heavy metals are naturally found in the ecosystem, and their presence in the freshwater river is increasing through anthropogenic activities which pose a threat to living beings. In this study, heavy metal concentrations (Zn, Mn, Cu, Cd, Cu, Cr, Pb, and Ni) in different organs (muscle, skin, and gill) of fish from the Padma River were evaluated to quantify, and compare the contamination levels and related human health risks. The results revealed that the heavy metal concentrations in the water, surface sediments, and fish taken from the Padma River were far below the WHO/USEPA's permitted limits. The estimated daily intake (EDI) value in muscle was less than the tolerable daily intake (TDI). The target hazard quotient (THQ) and hazard indexes (HI) were less than 1, showing that consumers face no non-carcinogenic risk (CR). CR values of Cu, Cd, Cr, Pb, and Ni ranged from 4.00 × 10^-8 to 6.35 × 10^-6, less than 10^-4, and total carcinogenic risk (CRt) values ranged from 9.85 × 10^-6 to 1.10 × 10^-5, indicating some pose a CR from consumption of those fish from the Padma River. To establish a more accurate risk assessment, numerous exposure routes, including inhalation and cutaneous exposure, should be explored.

• Advances in environmental research
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• 제3권1호
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• pp.71-86
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• 2014

Macronutrients ($Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$), yield and yield components, bioaccumulation and translocation of metal in plant parts of three Vigna species (V. cylindrica, V. mungo, V. radiata) were evaluated at 0, 50, 100 and $150mgkg^{-1}$ soil of Nickel (Ni). A marked inhibition (p < 0.001) in the distribution of various macronutrients was noticed in these Vigna species except for $Mg^{2+}$ content of the shoot and leaves. Similarly, all species retained more $Ca^{2+}$ in their roots (p < 0.05) as compared to the aerial tissues. Ni induced a drastic decline (p < 0.001) for various yield and yield attributes except for 100 seed weight. Toxicity and accumulation of Ni in plant tissues considerably increased in a concentration dependent manner. Vigna species signify an exclusion approach for Ni tolerance as both bioaccumulation factor (BF) and translocation factor (TF) were less than 1.0. The Ni content of plants being root > shoot > leaves > seeds. Scoring for percentage stimulation and inhibition (respective to control) at varying levels of Ni revealed tolerance of the species in an order of V. radiata > V. cylindrica > V. mungo. The acquisition of Ni tolerance in V. radiata seems to occur through an integrated mechanism of metal tolerance that includes sustainable macronutrients uptake, stronger roots due to greater deposition of $Ca^{2+}$in the roots, restricted transfer of Ni to above ground tissues and seeds as well as exclusion capacity of the roots to bind appreciable amount of metal to them. Thus, metal tolerant potential of V. radiata could be of great significance to remediate metal contaminated soil owing lesser impact of Ni on macro-nutrients, hence the yield.

• Advances in environmental research
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• 제9권3호
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• pp.175-189
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• 2020

Municipal solid waste disposal is considered as one of the most important risks for environmental contamination which necessitates the development of strategies to reduce destructive consequences on the ecosystem as related especially to heavy metal accumulation. This study investigates heavy metal (i.e., As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) accumulation in the Tonekabon region, NW of Iran that is related to city waste disposal and evaluates the environmental impact in the Caspian Sea coastal region. For this purpose, after performing field studies and collecting 50 soil specimens from 5 sites of the study area, geochemical tests (i.e., inductively coupled plasma mass spectrometry, atomic absorption spectroscopy and x-ray fluorescence) were conducted on the soil specimens collected from the 5 sites (named as Sites A1, A2, A3, A4 and A5) and the results were used to estimate the pollution indices (i.e., geo-accumulation index, normalized enrichment factor, contamination factor, and pollution load index). The obtained indices were utilized to assess the eco-toxicological risk level in the landfill site which indicated that the city has been severely contaminated by Cu, Mn, Ni, Pb and Zn. These levels have been developed along the stream towards the nearshore areas indicating uptake of soil degradation. The heavy metal contamination was classified to range from unpolluted to highly polluted, which indicated serious heavy metal pollution in the study area as related to municipal solid waste disposal in Tonekabon.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.131-137
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• 2006

This study was investigated the contents of heavy metals in plants at Dalcheun mine area, in order to offer basic data for phytoremedation on soil contamination by heavy metals. As the results of this study, the contents of Ni, As, Cd in plants were the highest at the west area of Dalcheun mine area. But the content of Zn was similar in all of Dalcheun mine area. For the herbaceous plants, the contents of heavy metals were higher in plants which were included in Gramineae and Compositae than any other families. And then the contents of Ni, Zn, Cd in root were higher $1.4{\sim}1.8$ times than stem, especially the content of As was higher 4 times. For the trees, the contents of heavy metals were usually high in Zanthoxylum piperitum, Pine tree, Chestnut tree, Quercus acutissima and Lindera obtusiloba. The contents of heavy metals with parts of tree were almost same range. All experimental result, we paid attention on two conclusions. First, the contents of heavy metals in herbs was higher than in trees. And second, if there were some spices that the content of heavy metal in leave were higher than in root, they could accumulate that kind of heavy metal. Therefore, It is above 2 times which the content of heavy metal in the leave is higher than in the root about herbs, that kind of plants was regarded as a accumulation species. According as the heavy metals, accumulation species were selected. We think that the accumulation species are able to absorb the heavy metals from the soil, they will make use of phytoremedation on contaminated soil by heavy metals.

• 한국지구과학회지
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• 제38권7호
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• pp.469-480
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• 2017

Controversy has surrounded the potential impacts of phytoplankton on the tropical climate, since climate models produce diverse behaviors in terms of the equatorial mean state and El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) amplitude. We explored biophysical impacts on the tropical ocean temperature using an ocean general circulation model coupled to a biogeochemistry model in which chlorophyll can modify solar attenuation and in turn feed back to ocean physics. Compared with a control model run excluding biophysical processes, our model with biogeochemistry showed that subsurface chlorophyll concentrations led to an increase in sea surface temperature (particularly in the western Pacific) via horizontal accumulation of heat contents. In the central Pacific, however, a mild cold anomaly appeared, accompanying the strengthened westward currents. The magnitude and skewness of ENSO were also modulated by biophysical feedbacks resulting from the chlorophyll affecting El $Ni{\tilde{n}}o$ and La $Ni{\tilde{n}}a$ in an asymmetric way. That is, El $Ni{\tilde{n}}o$ conditions were intensified by the higher contribution of the second baroclinic mode to sea surface temperature anomalies, whereas La $Ni{\tilde{n}}a$ conditions were slightly weakened by the absorption of shortwave radiation by phytoplankton. In our model experiments, the intensification of El $Ni{\tilde{n}}o$ was more dominant than the dampening of La $Ni{\tilde{n}}a$, resulting in the amplification of ENSO and higher skewness.

• 생태와환경
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• 제53권1호
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• pp.91-101
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• 2020

본 연구에서는 특별관리해역인 시화호 유역의 산업단지 하천에 강우 시 비점오염의 형태로 유입되는 중금속의 유출 특성 파악 및 오염원 파악을 하천 토구를 통해 배출되는 강우유출수 내 용존 및 입자성 중금속(Cr, Co, Ni, Cu, Zn, As, Cd, Pb)을 조사하였다. 용존성 Co와 Ni은 강우 초반에 고농도로 유출된 후 시간에 따라 감소하는 결과를 보였으나, 대부분의 원소는 조사시기별 강우량 및 유량 변화에 따라 각각 다른 특징을 보였다. 입자성 중금속의 경우, 시간에 따른 부유물질의 농도 변화와 유사한 경향을 보였다. 강우유출수 내 존재하는 중금속 중 Co, Ni, Zn는 용존 상태로 유출되는 비율이 높았고, Cr, Cu, Pb은 입자상 유출 비율이 상대적으로 높았다. 입자 상태로 유출되는 중금속의 인위적 오염도를 평가하기 위해 농집지수를 계산한 결과, Cu, Zn, Cd은 very highly polluted에 해당하는 심각한 오염수준으로 나타났다. 연구지역인 3간선수로 유역 인근의 도로먼지 중 125 ㎛ 이하에서의 중금속 농도와 비교한 결과, 강우유출수 내 Cu, Zn, Cd의 중금속이 금속제조관련 시설에서 절삭 혹은 가공 중에 발생하여 산업시설 표면에 축적되어 있는 금속물질이 강우유출수와 함께 수환경으로 유출된 것을 알 수 있었다. 강우유출수 내 총중금속 평균 유출부하량은 1회 강우 시 Cr 128 g, Co 12.35 g, Ni 98.5 g, Cu 607.5 g, Zn 8,429.5 g, As 6.95 g, Cd 3.7 g, Pb 251.75 g으로 금속제조와 관련된 산업시설이 주로 존재하는 유역의 특성을 잘 반영한 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권3호
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• pp.27-42
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• 2018

It is important to identify the contaminant sources and to evaluate the fate and transport of heavy metals to crops in agricultural lands. This study was conducted to evaluate metal sources and its transfer and accumulation to crop in agricultural soils. Pollution indices were calculated and multivariate analysis was performed to identify metal sources. To evaluate transfer and accumulation of metals to crops, the contents of phytoavailable metals were evaluated by using single extraction method and the correlation between metal content and soil properties was analyzed. Also the BCF was quantitatively evaluated for investigating the metal transition to each crop grown in the research area. As a result, Cr, Ni, and Co were expected to be mainly derived from geologic factors due to weathering of certain parent rocks. The content of nickel in soils of the research area was slightly higher than that of the concern level criteria based on total concentration, but the amount transferred and accumulated in the crops was actually low. Understanding the contamination characteristics by investigating the pollution sources of heavy metals and its transfer and accumulation to crops through various evaluation techniques could provide important information for proper management of the agricultural land.