• The Korean Journal of Ecology
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• 제27권5호
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• pp.301-306
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• 2004

The sensitivity to Cd of three ectomycorrhizal fungi, Paxillus involutus, Suillus bovinus and Rhizopogon subcaerulescens, was assessed and compared in terms of radial growth and dry mass production, using both agar and liquid culture. The radial growth of S. bovinus and R. subcaerulescens was significantly reduced at the lowest concentration (0.1mg Cd/L). The 50% effective concentration (EC$_{50}$) values calculated from radial growth rates of the ectomycorrhizal fungi showed that the sensitivity of the fungi to Cd was greatest in S. bovinus and lowest in R. subcaerulescens. Cadmium addition also significantly decreased dry mass production of the ectomycorrhizal fungi. The sensitivity of the fungi to Cd in terms of dry mass production, was greatest in S. bovinus and lowest in P. involutus. Higher growth rates of P. involutus and melanisation of R. subcaerulescens appeared to contribute to reduced Cd toxicity.

• 한국환경과학회지
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• 제22권2호
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• pp.187-193
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• 2013

Dry matter allocation characteristics of Calystegia soldanella, grown in pots, was analysed to assess its plasticity in response to water-stressed conditions. As water was withheld leaf water potential between the two watering treatments was similar during the first 6 days, followed by a rapid decrease in water-stressed plants. The minimum leaf water potential was -1.50 MPa on day 15 and the maximum leaf water potential was about -0.5 MPa on day 0 in water-stressed plants. In well-watered plants leaf water potential was maintained almost consistently throughout the experiment. There was no significant difference in plant dry weight between the two watering treatments for 9 days after the start of experiment and that was remarkably increased thereafter, compared with that remained without any increase in water-stressed plants. In dry mass partitioning, however, the water-stressed plants showed a great plasticity, showing that there were 1.81, 1.35 and 0.81 times increase in root, stem and leaf, respectively. Dry mass partitioning in well-watered plants varied from 2% to 5%. The difference of dry mass partitioning between the two watering treatments was reflected in leaf mass per unit area (LMA) and root/shoot (R/S) ratio. LMA in water-stressed plants was lower than that in well-watered plants, while R/S ratio in water-stressed plants was higher in well-watered plants. This means that the water-stressed plants reduced its leaf area and increased dry mass partitioning into root and stem during the progress of soil drying. These results indicate that Calystegia soldanella inhabiting in sand dune cope with water stress with high plasticity which can adjust its dry mass partitioning according to soil water conditions.

• 생태와환경
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• 제41권3호
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• pp.320-330
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• 2008

소하천에 서식하는 수서곤충 29 분류군에 대한 몸길이와 건조질량, 그리고 회분외질량에 관한 회귀식이 자연 log로 변환된 멱함수를 이용하여 구해졌다. 수서곤충은 강원도 북부지방의 산간계류에서 채집되었다. 각 분류군에서 주어진 몸길이에 대해 회귀식이 예측하는 건조질량은 기 보고된 다른 저자들의 예측값과 대체로 유사하였지만, 체벽이 연하고 이동할 때 몸을 수축-이완하는 분류군에서는 다른 저자들이 예측값에 비해 높았다. 수서곤충의 평균 회분율은 건조질량의 10%였으며, 섭식기능군간 차이는 인정되지 않았다.

• 환경영향평가
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• 제8권2호
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• pp.31-44
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• 1999

Atmospheric dry deposition flux and ambient particle mass size distribution were measured to evaluate the impact of atmospheric deposition around the Nanjido landfill sites. Wind direction affects greatly on the variation of mass flux and mass size distribution and made two times higher when the wind was blown from the road side. The effect of Nanjido landfill on the mass size distribution was significant comparing to simultaneously measured mass size distribution at the other sampling site. The results showed that the particle diameter bigger than $10{\mu}m$ explained the majority of atmospheric dry deposition flux. A survey was also carried out to investigate the contamination of soils in a completed Nanjido landfill. The chemical properties of the soil analyzed in the present study include pH, oxidation-reduction potential (ORP), anion and cation concentration, total organic carbon(TOC), and some-metal elements concentrations were analyzed. Microbial activity in the soils was also evaluated by measuring dehydrogenase activities. TOC in the soil contaminated with leachate was $467.0{\mu}g/g-dry$ soil, and the TOC in the soil, where Nanjido landfill gases were emitted from, was $675{\mu}g/g-dry$ soil. The highest microbial activity of $968.0{\sim}2147{\mu}g-TPF/g-dry$ soil day was found in the soil spouting Nanjido landfill gases. Compared with those in the uncontaminated soil, the concentrations of Cr, Cu and Ph in the contaminated soil were higher.

• 원예과학기술지
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• 제31권5호
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• pp.565-572
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• 2013

본 연구의 목적은 고압나트륨등 광원(HPS)을 조사하여 파프리카의 동적생장과 기관별 건물분배율 및 광이용효율에 미치는 효과를 구명하고자 수행하였다. 파프리카 육묘는 2010년 9월 29일에 $m^2$당 3.75주를 정식하여 2010년 12월 14일부터 HPS 광원을 실험종료일까지 하루 16시간 조사하였다. HPS 처리는 엽수를 증가시켰으나, 절간수와 엽면적에는 미비한 영향을 미쳤다. HPS 처리구의 초장은 대조구에 비해 짧았으나, 줄기당 착과수의 증가를 나타냈다. 줄기와 과실 및 총건물중은 HPS 처리구가 대조구보다 각각 28.5%, 97.1%, 67.8%를 증가시켰다. 총 건물중의 증가율 대비 엽과 줄기 생장율을 비율로 나타낸 각 기관의 건물분배율은 생육초기에 45-47%로 동일하다가 과실의 생장이 시작되는 시점에서 급격히 감소하였다. 영양생장기관으로의 건물분배율은 대조구에서 HPS 처리구보다 4% 높았다. 과실로의 평균 건물 분배율을 HPS 처리구에서 대조구에 비해 14.2% 증가하였다. 동적생장량은 지수선형함수의 최대상대생장율, 최대 절대생장율 및 손실일수로 잘 묘사할 수 있었다. 대조구에 비해 처리구의 엽의 최대절대생장율은 18.6%, 줄기는 74.7%, 과실은 143.5%가 증가하는 것으로 추정되었다. 총 건물중에 대한 광이용효율(LUE)은 HPS 처리구에서 $4.90g{\cdot}MJ^{-1}$로 대조구의 $3.84g{\cdot}MJ^{-1}$ 높았으며, 영양생장기관의 LUE는 HPS 처리구가 $1.56g{\cdot}MJ^{-1}$로 대조구의 $1.61g{\cdot}MJ^{-1}$보다 약간 낮았으며, 과실 생산에 대한 LUE는 처리구가 $3.34g{\cdot}MJ^{-1}$로 대조구 $2.23g{\cdot}MJ^{-1}$보다 49.8% 증가하였다. 처리간 총 건물중의 LUE의 차이는 HPS 처리구의 과실생산에 대한 LUE가 높았기 때문에 발생되었다.

• 한국입자에어로졸학회지
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• 제5권4호
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• pp.179-188
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• 2009

The dry deposition fluxes of particulate polychlorinated biphenyls (PCBs) were measured along with their mass size distributions at Seoul and Incheon in fall in 1999. The dry deposition fluxes of PCBs were in the range of $16.7{\sim}62.2ng/m^2/day$. The ambient concentrations of particulate PCBs were in the range of 0.07 to $0.20ng/m^3$. Generally, the mass size distribution of particulate PCBs shows bi-modal distribution. The mass fraction of PCBs in the fine particle fraction ($D_p<2.1 {\mu}m$) was over than 55% of the total PCBs concentrations. It was found that Seoul and Incheon were not the major source of PCBs emissions in Korea. Based on the comparison with the measurement data in summer, 1999, it is likely that both the dry deposition fluxes and ambient particulate PCBs concentrations were not site-specific.

• Journal of Ginseng Research
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• 제38권1호
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• pp.73-77
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• 2014

Field and nutrient cultures of American ginseng (Panax quinquefolius L.) were used to establish foliar symptoms related to boron (B) concentration in leaves and soils, and to evaluate radish as a time-saving model system for B nutrition. Application of excess B, 8 kg/ha versus the recommended 1.5 kg/ha, to field plantings of 2-, 3-, and 4-yr-old American ginseng plants just prior to crop emergence caused, within 4 wk after crop emergence, leaf symptoms of chlorosis followed by necrosis starting at the tips and progressing along the margins. The B concentration in leaves of 2-4-yr-old plants receiving 1.5 kg/ha Bwas $30{\mu}g/g$ dry mass compared to $460{\mu}g/g$ dry mass where 8 kg/ha B was applied. Similarly, B concentration in soils receiving the lower B concentration was 1.8 mg/g dry mass and $2.2-2.8{\mu}g/g$ dry mass where the higher B concentration was applied. Application of 8 kg/ha B reduced the dry yield of 3rd-yr roots by 20% from 2745 kg/ha to 2196 kg/ha and 4th-yr roots by 26% from 4130 kg/ha to 3071 kg/ha. Ginseng seedlings and radish were grown under greenhouse conditions in nutrient culture with four B concentrations ranging from 0 mg/L to 10 mg/L. At 5 mg/L and 10 mg/L ginseng and radish developed typical leaf B toxicity symptoms similar to those described above for field-grown plants. Increasing B in the nutrient solution from 0.5 mg/L to 10 mg/L decreased, in a linear fashion, the root and leaf dry mass of ginseng, but not radish. Given the many similarities of ginseng and radish to B utilization, radish might be used as a timesaving model system for the study of B, and other micronutrients, in the slow-growing perennial ginseng.

• 한국유기농업학회지
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• 제11권4호
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• pp.103-115
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• 2003

In order to investigate the possibility for use to control environmental pollution, Kenaf(Hibiscus cannabinus L.) was used to obtain information of their growth and $CO_2$ response under different temperatures and $CO_2$ concentration. The highest percentage of germination and aboveground dry mass of Kenaf were found at 30$^{\circ}C$ and 35$^{\circ}C$ by 89.0% and 3.2g, respectively under different temperatures. The amount of $CO_2$ absorption and aboveground dry mass production of Kenaf were higher than those of maize during the whole growing period and the last sampling of aboveground dry mass of Kenaf and maize were 252.9g and 200.8g, respectively. The highest plant height was found at 400ppm by 131.0cm and the next was in the order of 600ppm by 1293cm, and 800ppm by 108.8cm. Leaf area was higher in the order of 400ppm > 600ppm > 800ppm, whereas leaf dry mass was in the order of 800ppm > 600ppm > 400ppm under different $CO_2$ concentration, showing that leaf became thicker as $CO_2$ concentration was increased. Days from seeding to flowering became shorter by 13 days in 35/25$^{\circ}C$ compared with 25/15$^{\circ}C$ between two temperature regimes and they also became shorter as $CO_2$ concentration was increased. Aboveground dry mass was higher in 35/25$^{\circ}C$ than that of 25/15$^{\circ}C$ between two temperature regimes. while it was increased in the order of 800ppm > 600ppm > 400ppm as CO2 concentration was increased. Temporal changes of leaf dry mass during growth period showed no difference between $CO_2$ concentration in 25/15$^{\circ}C$ , but the highest of it was found at 800ppm in 35/25$^{\circ}C$. The highest temporaI increase of root dry mass was found at 800ppm in 25/15$^{\circ}C$, but 35/25$^{\circ}C$ showed no difference between different $CO_2$ concentration.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.76-85
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• 2003

Mass and elemental dry deposition fluxes and ambient particle size distributions were measured using dry deposition plates and a cascade impactor, from March to November 1998 in Seoul, Korea. During the spring sampling period several yellow sand events characterized by long range transport from China and Mongolia impacted the area. During these events the mass fluxes were statistically the same as during springtime non-yellow-sand events. However, most elemental fluxes were higher. In general, the flux ratios of both crustal (Al, Ca, Mn) and anthropogenic elements (Ni, Pb) to total mass measured during the daytime yellow-sand events were substantially higher than those measured in spring daytime during non-yellow-sand time periods. During all seasons the average measured daytime fluxes were about two times higher than at nighttime. The flux of primarily anthropogenic metals (Cu, Ni, Pb, Zn) and Mn was on average one to two orders of magnitude lower than the flux of the crustal metals Al and Ca. As is typically found two modes, fine (0.1∼l.0 $\mu\textrm{m}$) and coarse (1.0∼10.0 $\mu\textrm{m}$) were present in the measured size distributions (<10 $\mu\textrm{m}$). The particles in the coarse mode constitute a major portion of the measured mass size distribution during the yellow-sand events possibly due to the long-range transport of those particles from China.

• 한국물환경학회지
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• 제27권3호
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• pp.306-313
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• 2011

In this paper, runoff characteristics of South-Han river watershed in terms of refractory organic matters were investigated. The concentrations of DOC, POC, R-DOC, R-POC in runoff and flow rates were determined by monitoring 27 times in dry season and 4 times in rainy season. The concentrations of the dissolved refractory organic matter, R-DOC was the lowest in fall and similar in the other dry seasons. The particulate refractory organic matter, R-POC showed less fluctuation than R-DOC. In summer, mass loading was the highest than other dry seasons. The concentrations of R-DOC, R-POC were showed to be affected by runoff volume. The mass loading grows higher as runoff volume gets higher.