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Ecological Characteristics of Rhodotypos scandens Habitat in Imsil-gun, Jeollabuk-do, Korea (전라북도 임실군 병아리꽃나무 자생지의 생태적 특성)

  • Park, Kyung-Uk;Beon, Mu-Sup;Oh, Hyun-Kyung;You, Ju-Han
    • Journal of Environmental Impact Assessment
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    • v.24 no.4
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    • pp.352-366
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    • 2015
  • The purpose of this study is to offer the basic data to the habitat conservation and management by surveying and analysing the ecological characteristics such as the flora, vegetation structure and soil of Rhodotypos scandens habitat. The flora were summarized as 131 taxa including 57 families, 99 genera, 107 species, 1 subspecies, 17 varieties and 6 forms. The life forms grouped as in the follows; the megaphanerophytes(MM) were 21 taxa, 24 taxa of the microphanerophytes(M), 30 taxa of nanophanerophytes(N), 6 taxa of chamaiphytes(Ch), 20 taxa of hemicryptophytes(H), 17 taxa of geophytes(G), 12 taxa of therophytes(Th) and 1 taxa of hydrophytes(HH). The present conditions of communities were 8 types including Zelkova serrata, Quercus aliena, Ulmus parvifolia, Rhamnella frangulioides, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia. In case of the dominant species by layers, the tree layer species were Zelkova serrata, Quercus aliena, Ulmus parvifolia, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia, and the subtree layer species were Rhamnella frangulioides, Q. aliena, Z. serrata, A. julibrissin, U. parvifolia and Broussonetia kazinoki. The shrub layer species was Rhodotypos scandens. In the results of analyzing the diversity index, $H^{\prime}{_{max}}$ from 1.691 to 2.610, from 2.197 to 3.466 in H'max, from 0.646 to 0.903 in J' and from 0.097 to 0.354 in D. In the results of analysing the soil, there showed that acidity was 5.6, 0.5dS/m of electrical conductivity(EC), 59.1mg/kg of available $P_2O_5$, 49.7% of organic matter content, $0.4cmol^+/kg$ of exchangeable $K^+$, $13.5cmol^+/kg$ of exchangeable $Ca^{2+}$, $3.3cmol^+/kg$ of exchangeable $Mg^{2+}$.

Effect of Chelated Organic Minerals Liquid Fertilizer on Growth and Fruit Quality in 'Jukhyang' Strawberry (킬레이트 유기 미네랄 액비가 '죽향' 딸기의 생육 및 과실품질에 미치는 영향)

  • Noh, Hye-Ji;Chae, Hyo-Seok;Cho, Hyang-Hyun;Lee, Cheol-Gyu
    • Korean Journal of Organic Agriculture
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    • v.25 no.4
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    • pp.725-736
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    • 2017
  • TThis study investigated the influence of AGH-Ringer (chelated organic minerals liquid fertilizer) on the growth, yield, and fruit quality of 'Jukhyang' strawberry in a hydroponic system. The results revealed that AGH-Ringer group led to significantly higher plant length than that of the control group, and that leaf length and leaf width increased with increasing leaf area. In addition, the fresh and dry weights of leaves and SPAD unit, which measures leaf color also showed a significant increase with AGH-Ringer. However, the length and dry weight of roots did not show significant differences when compared to the control group. In the fruit quality analysis, AGH-Ringer group did not show any difference in fruit length compared to the control group, but it increased both the fruit weight, which, along with the simultaneous increase in fruit width, increased the yield per strawberry. Furthermore, AGH-Ringer group strengthened the red skin color of the fruit, and resulted in significantly greater hardness than that of the control group, but did not have any effect on the soluble solid content and acidity. As shown in the results, the AGH-Ringer group resulted in lesser mineral content and lower to medium EC (electrical conductivity) in comparison to the inorganic mineral hydroponic fertilizer, which was used as a control. However, it increased the leaf growth, fruit weight, and yield, and improved the fruit quality by increasing the soluble solid content in the hydroponic system of 'Jukhyang' strawberry. Therefore, based on this study, AGH-Ringer is thought to be a more effective hydroponic fertilizer than the inorganic mineral hydroponic fertilizer. Moreover, the field experiment demonstrated that AGH-Ringer is a useful hydroponic fertilizer convenient for application in farms. This study also proved that AGH-Ringer is a fertilizer that can promote plant nutrition by controlling the salinity of the soil and facilitating the absorption of necessary minerals in future soil cultivation, thereby providing basic data for organic farming.

Movement of Cold Water Mass in the Northern East China Sea in Summer (하계 동중국해 북부 해역에서 저층 냉수괴의 거동)

  • Jang, Sung-Tae;Lee, Jae-Hak;Kim, Cheol-Ho;Jang, Chan-Joo;Jang, Young-Suk
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.1
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    • pp.1-13
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    • 2011
  • The Yellow Sea Cold Water (YSCW) is formed by cold and dry wind in the previous winter, and is known to spread southward along the central trough of the Yellow Sea in summer. Water characteristics of the YSCW and its movement in the northern East China Sea (ECS) are investigated by analyzing CTD (conductivity-Temperature-Depth) data collected from summertime hydrographic surveys between 2003 and 2009. By water mass analysis, we newly define the North Western Cold Water (NWCW) as a cold water mass observed in the study area. It is characterized by temperature below $13.2^{\circ}C$, salinity of 32.6~33.7 psu, and density (${\sigma}_t$) of 24.7~25.5. The NWCW appears to flow southward at about a speed less than 2 cm/s according to the geostrophic calculation. The newly defined NWCW shows an interannual variation in the range of temperature and occupied area, which is in close relation with the sea surface temperature (SST) over the Yellow Sea and the East China Sea in the previous winter season. The winter SST is determined by winter air temperature, which shows a high correlation with the winter-mean Arctic Oscillation (AO) index. The negative winter-mean AO causes the low winter SST over the Yellow Sea and the East China Sea, resulting in the summertime expansion and lower temperature of the NWCW in the study area. This study shows a dynamic relation among the winter-mean AO index, SST, and NWCW, which helps to predict the movement of NWCW in the northern ECS in summer.

Evaluation of Growth Inhibition Causes on Perennial Ryegrass(Lolium perennial L.) in Afforesting Area (인공배양토 식생지역에서의 페레니얼 라이그래스 생육저해 원인 평가)

  • Lee, In-Bog;Kim, Pil-Joo
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.4
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    • pp.212-219
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    • 2004
  • To minimize the danger of soil erosion and settle habitats earlier, afforestation, which vegetates bare slopes, is selected as an environmental recovering technology. Large portions of these areas often are suffered by a bad germination and growth inhibition of sprayed seeds. Afforested materials collected in the normal and damaged sites were not any big difference in chemical characteristics and biological response to ryegrass. But background soil of the damaged site has very low pH (3.6) and high contents of iron and aluminum compared with them of the normal sites. Both germination and root growth of ryegrass were inhibited severely in the water extracts of damaged soils, but not in the water extracts of normal sites. Groundwater collected nearby the damaged sites was very strong acidic (pH 33) and exhibited a high value of electrical conductivity and high contents of iron and aluminum. In the ground water, germinated ryegrass was scarcely grown. In Al standard solution, the root growth of ryegrass was inhibited over 50% in 0.5 mM in pH 3.5-4.5 and in 1.4 mM in pH 5.5, which seems to be related to $Al^{3+}$ activity in solution. In the ferric Fe ($Fe^{3+}$) standard solution, ryegrass growth was inhibited over 50% in the concentration of 14-19 mM in root and 23-25 mM in shoot. This strong tolerance of ryegrass to $Fe^{3+}$ might be concerned with the very low activity of $Fe^{3+}$ at pH 3.5-5.5. In contrast, ryegrass responded very sensitively to ferrous Fe ion ($Fe^{2+}$), especially in root growth: $Fe^{2+}$ concentrations corresponding to 50% growth reduction were 0.3-0.4 mM at pH 3.5-5.5 in roots. This high growth inhibition should be related to the high ion activity of $Fe^{2+}$ irrespective of different pH conditions. In conclusion, low pH and high contents of $Fe^{2+}$ and aluminum seem to be caused by pyrite and be closely related to the growth inhibition of ryegrass seeded in afforested area.

Salt Accumulation in Horticultural Soils of PE Film House in Chungbuk Area (충북지역(忠北地域) 시설원예재배지(施設園藝栽培地) 토양(土壤)의 염류집적(鹽類集積) 실태조사(實態調査))

  • Yuk, Chang-Soo;Kim, Jai-Joung;Hong, Soon-Dal;Kang, Bo-Goo
    • Korean Journal of Soil Science and Fertilizer
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    • v.26 no.3
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    • pp.172-180
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    • 1993
  • Chemical properties of the soils were surveyed in the field of vinyl houses concentrated in the area of Bunpyong-dong and Shinchon-dong of Cheongju, Chilgeum-dong of Chungju and Gageum-myeon of Jungweon-gun. Chungcheongbuk-do province. 1. Content of chemical component of the soil in the vinyl house was higher than in open field. In more than half of the vinyl house soils surveyed, electric conductivity was more than 4.0 mmhos/cm and available phosphate was more than 1,000ppm. 2. Contents of availble phosphate and exchangeable potassium were increased with years of cultivation and their content of accumulation in soil were in the order of Bunpyong-dong>Shinchon-dong>Gageum-myeon>Chilgeum-dong. While their mobility was comparatively low. 3. $NO_3$-N content was remarkably higher in vinyl house soil and the older in cultivation made $NO_3$-N content higher same as the case of available phosphate content. However easy leaching of $NO_3$-N through soil profile is expected due to the fact that $NO_3$-N content was rapidly decreased by removal of polyethylene film cover from the frame of house after harvest of crops. 4. It is a tendency that various chemical contents of vinyl house soils wer higher in 1992 than in 1988~1990, especially much higher from the area of Bunpyong-dong and Shinchon-dong of Cheongju. 5. Salt accumulation in vinyl house soil has been increased with continuing cultivation. Therefore amount of fertilizer application should be controlled in order to avoid salt toxicity, quality deterioration for crop and salt contamination of ground water.

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Physico-Chemical Properties of Rainfall Interception Culture and Open Field Culture Soils of Rubus sp. In Gochang-gun, Jeollabuk-do (고창지역 복분자 비가림하우스 토양과 노지토양의 물리·화학적 특성)

  • Chung, Byung-Yeoup;Lee, Kang-Soo;Kim, Myung-Kon;Choi, Young-Hee;Kim, Moo-Key;Cho, Jae-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.5
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    • pp.303-309
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    • 2008
  • The physico-chemical properties of the rainfall interception culture (85 sites) and the open field culture soils (85 sites) in the area of Gochang-gun, Jeollabuk-do were surveyed. Soil textural distribution of the rainfall interception culture and the open field culture soils was 74% and 64% for silt loam, 16% and 35% for loam, and 10% and 1% for clay, respectively. The percentage of aggregate rates was higher in the open field culture soils (60.06%) than rainfall interception culture soils (55.84%). Electrical conductivity, exchangeable cations, and anions in the rainfall interception culture soils were higher than those in open field soils. Specially, accumulated amount of anion in rainfall interception culture soils was remarkably higher 2~3 times than open field culture soils. The results from the analyses of rainfall interception culture soils suggested that the most critical problem is the salts accumulation caused by over-fertilization of chemical fertilizer and compost. Therefore, application rates of chemical fertilizer and compost should be controlled in order to conservation of soil and water for sustainable agriculture.

Cryosurgery of Lung with 2.4 mm Cryoprobe: An Experimental in vivo Study of the Cryosurgery in Canine Model (냉동침을 이용한 폐 냉동수술의 동물실험: 냉동수술 방법의 비교 실험)

  • Kim Kwang-Taik;Chung Bong-Kyu;Lee Sung-Ho;Cho Jong-Ho;Son Ho-Sung;Fang Young-Ho;Sun Kyung;Park Sung-Min
    • Journal of Chest Surgery
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    • v.39 no.7 s.264
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    • pp.520-526
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    • 2006
  • Background: The clinical application of cryosurgery the management of lung cancer is limited because the response of lung at low temperature is not well understood. The purpose of this study is to investigate the response of the pulmonary tissue at extreme low temperature. Material and Method: After general anesthesia the lungs of twelve Mongrel dogs were exposed through the fifth intercostal space. Cryosurgical probe (Galil Medical, Israel) with diameter 2.4 mm were placed into the lung 20 mm deep and four thermosensors (T1-4) were inserted at 5 mm intervals from the cryoprobe. The animals were divided into group A (n=8) and group B (n=4). In group A the temperature of the cryoprobe was decreased to $-120^{\circ}C$ and maintained for 20 minutes. After 5 minutes of thawing this freezing cycle was repeated. In group B same freezing temperature was maintained for 40 minutes continuously without thawing. The lungs were removed for microscopic examination on f day after the cryosurgery. In four dogs of the group A the lung was removed 7 days after the cryosurgery to examine the delayed changes of the cryoinjured tissue, Result: In group A the temperatures of T1 and T2 were decreased to the $4.1{\pm}11^{\circ}C\;and\;31{\pm}5^{\circ}C$ respectively in first freezing cycle. During the second freezing period the temperatures of the thermosensors were decreased lower than the temperature during the first freezing time: $T1\;-56.4{\pm}9.7^{\circ}C,\;T2\;-18.4{\pm}14.2^{\circ}C,\;T3\;18.5{\pm}9.4^{\circ}C\;and\;T4\;35.9{\pm}2.9^{\circ}C$. Comparing the temperature-distance graph of the first cycle to that of the second cycle revealed the changes of temperature-distance relationship from curve to linear. In group B the temperatures of thermosensors were decreased and maintained throughout the 40 minutes of freezing. On light microscopy, hemorrhagic infarctions of diameter $18.6{\pm}6.4mm$ were found in group A. The infarction size was $14{\pm}3mm$ in group B. No viable cell was found within the infarction area. Conclusion: The conductivity of the lung is changed during the thawing period resulting further decrease in temperature of the lung tissue during the second freezing cycle and expanding the area of cell destruction.

A Study on the Effect of O$_2$ annealing on Structural, Optical, and Electrical Characteristics of Undoped ZnO Thin Films Deposited by Magnetron Sputtering (산소 어닐링이 마그네 트론 스퍼터링으로 증착된 undoped ZnO박막의 구조적, 광학적, 전기적 특성에 미치는 영향에 대한 연구)

  • Yun, Eui-Jung;Park, Hyeong-Sik
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.7
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    • pp.7-14
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    • 2009
  • In this paper, the effects of annealing conditions on the structural ((002) intensity, FWHM, d-spacing, grain size, (002) peak position), optical (UV peak, UV peak position) and electrical properties (carrier concentrations, resistivity, mobility) of ZnO films were investigated. ZnO films were deposited onto SiO$_2$/si substrates by RF magnetron sputtering from a ZnO target. The substrate was not heated during deposition. ZnO films were annealed in temperature ranges of $500\sim650^{\circ}C$ in the O$_2$ flow for 5$\sim$20 min. The film average thicknesses were in the range of 291 nm. The surface morphologies and structures of the samples were characterize by SEM and XRD, respectively. The optical properties were evaluated by photoluminescence (PL) measurement at room temperature (RT) using a He-Cd 325 nm laser. As the annealing temperature and time vary, the following relations were also observed: (1) proportional relationships among UV intensity (002) intensity, and grain size exist, (2) UV intensity is inversely proportional to FWHM, (3) there is no special relationship between UV intensity and electron carrier concentrations, (4) d-spacing is inversely proportional to (002) peak position, (5) UV peak position in the range of 3.20$\sim$3.24 eV means that ZnO films have a n-type conductivity which was consistent with that obtained from the electrical property, (6) the optimal conditions for the best optical and structural characteristics were found to be oxygen fraction, (O$_2$/(O$_2$+Ar)) of 0.2, RF power of 240W, substrate temperature of RT, annealing condition of 600$^{\circ}C$ for 20 min, and sputtering pressure of 20 mTorr.

Study on the Geoelectrical Structure of the Upper Crust Using the Magnetotelluric Data Along a Transect Across the Korean Peninsula (한반도 횡단 자기지전류 탐사에 의한 상부 지각의 지전기적 구조 연구)

  • Lee, Choon-Ki;Kwon, Byung-Doo;Lee, Heui-Soon;Cho, In-Ky;Oh, Seok-Hoon;Song, Yoon-Ho;Lee, Tae-Jong
    • Journal of the Korean earth science society
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    • v.28 no.2
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    • pp.187-201
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    • 2007
  • The first magnetotelluric (MT) transect across the Korean Peninsula was obtained traversing from the East Sea shoreline to the Yellow Sea shoreline. The MT survey profile was designed perpendicular to the strike of the principal geologic structure of the Korean Peninsula $(N30^{\circ}E)$, so-called 'China direction'. MT data were achieved at 50 sites with spacings of $3{\sim}8km$ along the 240 km survey line. The impedance responses are divided into four subsets reflecting typical geological units: the Kyonggi Massif, the Okchon Belt, the western part of the Kyongsang Basin, and the eastern part of the Kyongsang Basin. In the western part of the Kyongsang Basin, the thickness of the sedimentary layer is estimated to be about 3 km to 8 km and its resistivity is a few hundred ohm-m. A highly conductive layer with a resistivity of 1 to 30 ohm-m was detected beneath the sedimentary layer. The MT data at the Okchon Belt show peculiar responses with phase exceeding $90^{\circ}$. This feature may be explained by an electrically anisotropic structure which is composed of a narrow anisotropic block and an anisotropic layer. The Kyonggi Massif and the eastern part of Kyongsang Basin play a role of window to the deep geoelectrical structure because of the very high resistivity of upper crust. The second layers with highest resistivities in 1-D conductivity models occupy the upper crust with thicknesses of 13 km in the Kyonggi Massif and 18 km in the eastern Kyongsang Basin, respectively.

Growth Performance, Carcass Characteristics and Plasma Mineral Chemistry as Affected by Dietary Chloride and Chloride Salts Fed to Broiler Chickens Reared under Phase Feeding System

  • Mushtaq, M.M.H.;Pasha, T.N.;Akram, M.;Mushtaq, T.;Parvin, R.;Choi, H.C.;Hwangbo, J.;Kim, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.6
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    • pp.845-855
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    • 2013
  • Requirements of dietary chloride (dCl) and chloride salts were determined by using $4{\times}2$ factorial arrangement under four phase feeding program. Four levels (0.31, 0.45, 0.59 and 0.73%) and two sources ($NH_4Cl$ and $CaCl_2$) of the dCl were allocated to 1,472 chicks in eight dietary treatments in which each treatment was replicated four times with 46 birds per replicate. The four phase feeding program was comprised of four dietary phases: Prestarter (d 1 to 10), Starter (d 11 to 20), Grower (d 21 to 33) and Finisher (d 34 to 42); and diets were separately prepared for each phase. The cations, anions, pH, dissolved oxygen (DO), temperature, electrical conductivity (EC), total dissolved solids (TDS) and salinity were analyzed in drinking water and were not affected by dietary treatments. BW gain (BWG; $p{\leq}0.009$) and feed:gain (FG; $p{\leq}0.03$) were improved in $CaCl_2$ supplemented diets during d 1 to 10. The maximum response of BWG and FG was observed at 0.38% and 0.42% dCl, respectively, for d 34 to 42. However, the level of dCl for BWG during d 21 to 33 ($p{\leq}0.04$) and d 34 to 42 ($p{\leq}0.009$) was optimized at 0.60% and 0.42%, respectively. The level of dCl for optimized feed intake (FI; $p{\leq}0.006$), FG ($p{\leq}0.007$) and litter moisture (LM; $p{\leq}0.001$) was observed at 0.60%, 0.38% and 0.73%, respectively, for d 1 to 42. Water intake (DWI) was not affected by increasing dCl supplementation (p>0.05); however, the ratio between DWI and FI (DWI:FI) was found highest at 0.73% dCl during d 1 to 10 ($p{\leq}0.05$) and d 21 to 33 ($p{\leq}0.009$). Except for d 34 to 42 ($p{\leq}0.006$), the increasing level of dCl did not result in a significant difference in mortality during any phase. Blood pH and glucose, and breast and thigh weights (percentage of dressed weight) were improved while dressing percentage (DP) and gastrointestinal health were exacerbated with $NH_4Cl$ as compared to $CaCl_2$ supplemented diets ($p{\leq}0.001$). Higher plasma $Na^+$ and $HCO_3{^-}$ and lower $Cl^-$ and $Ca^{{+}{+}}$ were observed in $NH_4Cl$ supplemented diets ($p{\leq}0.001$). Increasing supplementation of dCl increased plasma $Cl^-$ ($p{\leq}0.04$; quadratically) and linearly reduced plasma $K^+$ ($p{\leq}0.001$), $Ca^{{+}{+}}$ ($p{\leq}0.003$), $HCO_3{^-}$ ($p{\leq}0.001$), and $Na^+$ ($p{\leq}0.001$; quadratically). Consequently, higher requirements of dietary chloride are suggested for feed intake; nevertheless, lower levels of dietary chloride are sufficient to support optimal BWG and FG with increasing age. The $NH_4Cl$ supplemented diets ameliorate breast and thigh meat yield along with overall energy balance (glucose).