• 제목/요약/키워드: Small Plant

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Effects of Environment Friendly Agricultural Materials to Insect Natural Enemies at Small Green Houses (소형포장에서 친환경농자재가 천적곤충에 미치는 영향)

  • Lee, Dae-Hong;Kang, Eun-Jin;Kang, Myong-Ki;Lee, Hee-Jin;Seok, Hee-Bong;Seo, Mi-Ja;Yu, Yong-Man;Youn, Young-Nam
    • Korean journal of applied entomology
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    • v.47 no.1
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    • pp.75-86
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    • 2008
  • Many kinds of environment friendly agricultural materials (EFAMs) were used for the plant protection, furthermore they support the growth of crops in the greenhouses and the kindly environment friendly farming. Natural enemies might be used for control of insect pest with EFAMs at the same space and time. For testing the toxicity of EFAMs against to natural enemies, 10 EFAMs were selected and tested in small greenhouses and farm's fields. In case of Harmonia axyridis larva, there was no predacious activity against cotton aphids in the block with EFAMMo L, EFAMPE D, EFAMME G and EFAMAE A, otherwise, aphid population was rapidly decreased in the control block without EFAMs. Both of Trialeurodes vaporariorum and Encarsia formosa population were slightly decreased in the block with EFAMs. There were significantly decreased in the block with IEFAM C, FEFAM D, EFAMSM Band EFAMPE D compared with control area. Especially, there was significantly maintained a very low population, both T. vaporariorum and E. formosa in the block with EFAMMo C. The parasitized ratio of Aphidius colemani is also very low in the block with EFAMs compared with control area. In the block with IEFAM C, FEFAM D, EFAMPE D and EFAMMo L, there were significantly different with control area in the number of mummies. Otherwise, in case of Diglyphus isaea and Liriomyza trifolii, there was no significantly different between blocks with and without EFAMs. In the block with EFAMMo C, Tetranychus urticae and Phytoseiulus persimilis populations were significantly maintained a very low level. However, the population of T. urticae was increased, but P. persimilis was decreased in the block with EFAMMo L.

Restoration for Evergreen Broad-leaved Forests by Successional Trends of Pasture-grassland in the Seonheulgot, Jeju-do (제주도 선흘곶 초지지역의 천이경향을 고려한 상록활엽수림 복원 연구)

  • Han Bong-Ho;Kim Jeong-Ho;Bae Jeong-Hee
    • Korean Journal of Environment and Ecology
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    • v.18 no.4
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    • pp.369-381
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    • 2004
  • This study was achieved to present the way to restore the Seonheulgot pasture-grassland damaged by landuse and interference for a long time to evergreen broad-leaved forests as the native vegetation structure. As a result of analyzing ecological succession tendency of structure in survey area, we established the optimal restoration model. The total of survey sites were 26, and the classified plant community types were four types by M.I.P of dominant woody species. Finally we classified the four types based on diameter of dominant woody species in canopy layer. The six community types are as follows: Community I was runner-shrub forest, community II was evergreen broad-leaved shrub forest, and community III was evergreen broad-leaved forest of small diameter. Community IV and V were evergreen broad-leaved forest of middle diameter. Community Ⅵ was evergreen broad-leaved forest of large diameter. The number of constituent species was 24 in community I, 28 in community II as the shrub forest, 16 as the evergreen broad-leaved forest of small diameter, 29 in community III, 30 in community IV as the evergreen broad-leaved forest of middle diameter and 27 in community Ⅵ as the evergreen broad-leaved forest of large diameter. The range of Shannon's index of all communitys was from 0.8763 to 1.2630 and the Similarity index between the community composed of middle diameter woody species and large diameter woody species. The ecological succession of community I, II, and III were changed from pasture-grassland to broad-leaved forest and the structure of community IV, V, and Ⅵ was similar to evergreen broad-leaved forest in warm temperate region. We suggest the restoration planting model evergreen broad-leaved forest of in Seonheulgot pasture-grassland, as follows: The target restoration vegetation were Castanopsis cuspidata var. sievoldii community and Queycus glauca community. Castanopsis cuspidata var. sievoldii and Quercus glauca should be dominant woody species in canopy layer, the number of trees was 10 per 100$m^2$, and Castanopsis cuspidata var, sievoldii, Quercus glauca, Camellia japonica, and Eurya japonica should be dominant woody species in the understory layer, the number of trees was 14 per 100$m^2$.

Studies on the Bare Rock-slope Conservation Measures (I) -Conservation and Revegetation by Parthenocissus spp.- (암벽면녹화공법개발(岩壁面綠化工法開發)에 관(關)한 연구(硏究)(I) - 담쟁이덩굴류(類)의 이용성개발(利用性開發) -)

  • Woo, Bo-Myeong
    • Journal of Korean Society of Forest Science
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    • v.37 no.1
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    • pp.1-16
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    • 1978
  • The study describes on the identification and morphological characteristics of each species, ecological characteristics and propagation techniques, and developing utilization measures of the Parthenocissus plants for environment conservation and revegetation of the babe rock-slopes. The following species and varieties are disscussed in this study; Parthenocissus tricuspidata (S. et Z.) Planch. var. veitchii Rehd. var. lowii Rehd. var. pupurea Hort. Parthenocissus quiquefolia (L.) Planch. var. engelmanni Rehd. var. saint-pauli Rehd. var. hirsuta Planch. Parthenocissus henryana Diels et Gilg. Parthenocissus thomsoni Planch. Parthenocissus heptaphylla Small. Parthenocissus inserta (Kern.) K. Fritsch. Parthenocissus laetevirens Rehd. Parthenocissus himalayana Planch. These are, in general, all vigorous self-clinging climbers that will quickly cover a wall and bare rock surfaces with a dense network of branch growths and beautiful green leaves which change to shades of scarlet and crimson before they fall in Autumn. Parthenocissus tricuspidata out of 8 species in the genus Parthenocissus is the most useful plant for the environment conservation including the bare rock-slope revegetation and for the production of food and shelter for wildlifes. This native of Korea clings by means of small rootlike holdfasts (adhesive discs) and holds (tendrils) to stone work or any other solid support, tenaciously.

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Loss of Specific Sequences in a Natural Variant of Potato Proteinase Inhibitor II Gene Results in a Loss of Wound-Inducible Gene Expression (감자의 단백질 분해효소 억제제 II 유전자의 특별한 염기서열의 자연적 제거로 인한 상처 유발성 발현의 소실)

  • Thornburg, Robert W.;Park, Sang-Gyu
    • Applied Biological Chemistry
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    • v.39 no.2
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    • pp.104-111
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    • 1996
  • We have isolated several proteinase inhibitor II genes pin2 from a Russet Burbank potato DNA library. One of these, pin2T was subcloned and a 1.8 kb Xbal/Nsil insert was sequenced. This fragment contained the complete Inhibitor II gene including 965 Up of flanking DNA upstream from the gene and 200 bp of flanking DNA downstream from the gene. The open reading frame encodes a protein that is similar to other reported proteinase Inhibitor II proteins. The DNA sequence of the 5' flanking region of pin2T from -714 to +1 is highly homologous (91% identity) with that of the previously isolated wound-inducible pin2K. There are, however, four small deletions in the pin2T promoter which are located at -221 to -200, -263 to -254, -523 to -426 and -759 to -708 relative to the transcription start site of the wound-inducible pin2K. Three of these deletions map to a portion of the promoter that controls the wound-inducibility of the proteinase inhibitor genes. Chimeric genes containing the promoter of the pin2T gene linked with the both CAT and GUS were constructed and transfered into tobacco plants. Analysis of these plants indicated that pin2T is not a wound-inducible gene but is expressed at low levels. Thus, wound-inducibility is lost with the concomitant natural deletion of three small regions of the promoter. Comparision of the sequences deleted in pin2T relative to the pin2K with Genebank sequences indicates that the deleted sequences contain a motif (consensus 5'-AGTAAA-3') that is found in many other wound-inducible genes but not easily found in the published promoter sequences of other plant genes. Nuclear proteins from unwounded and wounded potato leaves were bound to the proximal promoter region, downstream of the 5'-AGTAAA-3', of pin2T. The comparison of the pin2T gone with the pin2K gene indicates that the natural internal promoter deletions are likely responsible for loss of the wound-inducible phenotype in the pin2T gene.

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Population Structure and Habitat Characteristics of Deutzia paniculata Nakai, as an Endemic Plant Species in Korea (한반도 특산식물 꼬리말발도리 개체군 구조 및 서식지 특성)

  • Jung, Ji-young;Pi, Jung-hun;Park, Jeong-geun;Jeong, Mi-jin;Kim, Eun-hye;Seo, Gang-Uk;Lee, Cheul-ho;Son, Sung-won
    • Korean Journal of Ecology and Environment
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    • v.49 no.1
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    • pp.31-41
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    • 2016
  • Deutzia paniculata is an endemic species to the Korean Peninsula. Despite of importance for conservation, the population structure and habitat characteristics of D. paniculata have not been determined yet. We analyzed the ecological characteristics of the species based on the literature review and field survey. Field survey was conducted on May to October 2014 during which 11 quadrats of size $15{\times}15m$ were studied in six regions. Each of the quadrats were further divided into $5{\times}5m$ small quadrats and population characteristics were recorded. The population and habitat characteristics were analyzed, including species abundance (density and coverage), demographic attributes (flowering rates and fruiting plants), vegetation (structure, species composition), light availability (transmitted light and canopy openness) and soil characteristics (temperature and humidity). We found that D. paniculata mainly distributed in Gyeongsangdo (including Taebaek in Gangwondo) along a broad elevational range of 290~959 m (mean: 493 m) above sea level. In preferred habitat the species grows within the slope range of $7^{\circ}$ and $35^{\circ}$ with the average of $16^{\circ}$. D. paniculata was generally distributed on talus deposits and low adjacent slopes. The average number of individual plants per small quadrat was 12.5 with the mean density $0.5stems\;m^{-2}$. The vegetative reproduction was frequent in D. paniculata and mean flowering rate was as low as 15%. Altogether 138 taxa were found in whole observation area with the dominant tree species mainly spring ephemerals, such as Cornus controversa (importance value: 25.5%) and Fraxinus rhynchophylla (importance value: 15.8%). Although, C. controversa usually grows on steep slopes and F. rhynchophylla mostly distributed at high-altitudes, however, both species distributed in disturbed environments and among talus deposits. Thus based on our results, we concluded that D. paniculata is a disturbance-prone species, primarily existing in habitats subjected to natural disturbances, such as floods. The species occurs less at anthropogenically disturbed sites, thus there is no apparent threat to the populations and habitat of D. paniculata.

Production of Violacein by a Novel Bacterium, Massilia sp. EP15224 Strain (Violacein을 생산하는 Massilia sp. EP15224 균주)

  • Yoon, Sang-Hong;Baek, Hee-Jin;Kwon, Soon-Wu;Lee, Chang-Muk;Sim, Joon-Soo;Hahn, Bum-Soo;Koo, Bon-Sung
    • Microbiology and Biotechnology Letters
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    • v.42 no.4
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    • pp.317-323
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    • 2014
  • Violacein has received much attention due to its various important biological activities, including broad-spectrum antibacterial and antifungal activity, anti-malarial, anti-tumoral, anti-oxidant, and anti-diarrheal activities. EP15224 strain isolated from forest soils in Korea was found to be a new species belonged to the genus Massilia based on its 16S ribosomal DNA sequences. The 16S ribosomal DNA of strain EP15224 displayed 97% homology with Massilia sp. BS-1, the nearest violacein-producing bacterium. Strain EP15224 produced bluish-purple pigment well in a synthetic MM2 medium containing glucose, $(NH_4)_2SO_4$, $Na_2HPO_4{\cdot}7H_2O$, $KH_2PO_4$, $MgSO_4{\cdot}7H_2O$, and 1 mM $\small{L}$-tryptophan. The chemical analysis of the pigment by LC/MS/MS showed that it is violacein with molecular weight of 343.34. This is the second report on the production of violacein by a Massilia species. In this study, the optimal culture conditions for violacein production were established under which 280 mg/l crude violacein was produced : glucose 2 g/l, $(NH_4)_2SO_4$ 1 g/l, $Na_2HPO_4{\cdot}7H_2O$ 2 g/l, $KH_2PO_4$ 1 g/l, $MgSO_4{\cdot}7H_2O$ 0.1 g/l, L-tryptophan 0.24 g/l, 25 ml medium in a 250 ml flask, with an inoculumn size of 10% (v/v), 72 h of cultivation with 250 rpm at $25^{\circ}C$.

Studies on Heterostylism, Fertility, and Embryological Characteristics in Buckwheat. Fagopyrum esculentum (메밀의 이형예현상과 수정력 발생학적 특징에 관한 연구)

  • Man-Sang Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.31 no.2
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    • pp.129-142
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    • 1986
  • Fifty-five local collections of buck wheat, Fagopyrum esculentum, were investigated their ratios of long-styled (LS) and short-styled (SS) flowers, fertility, meiosis of megaspore and microspore mother cell, female and male gametogenesis, and egg apparatus in accordance with the sowing seasons (spring, summer), altitudes (20m, 50-100m, 300m), and parent style types (L, S). Also they were embryologically investigated the fertility, fertilizing phenomenon and proembryogenesis by the legitimate and illegitimate pollination. There were no differences in the ratios of long-styled and short-5tyled flowers along with altitudes, but more irregularness was observed in plain area than that in the mountaineous or coastal area. LS versus SS ratios by sowing seasons were significantly separated into 1 : 1 in the summer sowing (P 0.1), but they were irregularly separated in the spring sowing. The segregating ratios by parent style types showed more number of short-styled flower in the spring sowing, and were statistically seperated into 1 : 1 in the summer sowing (P 0.25), regardless to parent style types. In the artificial legitimate union, the seed setting rates of the summer sowing (59-61%) were much higher than those of the spring sowing (about 30%), but in the artificial illegitimate union the seed setting rates were only fructified about 0.8-1.8% in the spring sowing. The seed setting rates in accordance with flowering stages were larger in turn early, middle, late, in the summer sowing. The grain number and grain weight per plant of short-styled flower were more than those of long-styled one regardless to style types. The 1,000 grain weight of long-styled flower was heavier than that of short-styled one in large grain, but it was lighter than that of short-styled flower in small or medium grain. The percentage of normal female and male gametogenesis in the summer sowing were higher than those in the spring sowing. The ovule was atropous and two polar nuclei were a synkarion before flowering. The pollens germinated at 30 minuts after pollination and the pollen tube grew continually and penetrated into micropyle at 1.5-2 hours and the two male nuclei fertilized with egg nucleus at 3 -5 hours after pollination. Flertilizing times in summer were shorter than in autumn. The fertilized egg was divided in a small apical cell toward the interior of the embryo sac and a large basal cell toward the micropyle cell at 15-24 hours after pollination, and division times in summer were shorter than in autumn. The proembryo began the embryogenesis at 7-8 days and formed itself into the perfect embryo at 15 days after pollination.

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Studies on the morphological variation of plant organs of elongating node-part in rice plant (수도 신장 절위 경엽의 형태변이에 관한 연구)

  • 김만수
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.5 no.1
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    • pp.1-35
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    • 1969
  • Attempts were made to obtain the fundamental knowledge on the quantitative constitution status of leaves and stem of elongating node-part, and the relationships between these morphological characteristics along with the nitrogen contents of leaves and grain yield were examined varing application amounts of nitrogen in rice plant. I. The agronomic characteristics of leaves and nodes of elongation node-part (4-node parts from the top of stem) were observed at heading stage with 20 leading rice varieties of Kang Won district. The results are summarized as follows: 1. Leaf area magnitude of the flag and the fourth leaf was smaller than that of the second and the third with the average value of flag leaf 18.61 $cm^2$, the second leaf 21.84 $cm^2$, the third 21.52 $cm^2$ and the fourth 18.56 $cm^2$. The weight of leaf blade showed an isotonic tendency with the magnitude of leaf area with the value of the flag leaf 97.0 mg, the second leaf 117.1 mg, the third 115.4 mg, and the fourth 95.3 mg. The weight of each leaf sheath was remarkably larger at the higher node-part than at the lower node-part of the stem with the value of flag leaf sheath 176.3 mg, the second 163.7 mg, the third 163.4 mg and the fourth 123.9 mg. Accordingly, the total leaf weight of each part was larger at the second and the third leaf than at the first and the fourth. Total plant weight of each part (weight of leaf blade, leaf sheath, and culm) also was larger at the middle node-part. 2. Coefficients of variation for the varietal differences of the morphological characteristics of elongating node-part were 12.75% for the leaf area, 15.29% for the weight of leaf blade, 15.90%, for the weight of leaf sheath, 11.42% for the weight of internode, 15.45% for the leaf weight (leaf blade & leaf sheath) and 13.24% for the straw weight. And these coefficient values of the most characteristics were, on the whole, smaller at the second and the third node-part than at the first and the fourth node-part, but the coefficient value of the internode weight was rather small at the third and fourth node-part. 3. Constitutional ratio of each plant organ to the total plant weight in term of dry matter weight (excluding head and root wight) was 39.2% for the leaf sheath, 34.2% for the culm, 26.6% for the leaf blade. And ocnstitutional ratio of leaf sheath in term of dry matter weight was larger at the higher position in contrast with that of culm. 4. Average weight ration of leaf blade to culm, leaf sheath to culm, leaf blades to sheath and the leaf blades to culm plus leaf sheath were 77.7 %, 114.5%, 67.9% and 36.2%, respectively. With regard to the position of the plant organ, the weight ratio of leaf blade to culm and that of leaf sheath to culm were larger at higher part in contrast with that of leaf blade to leaf sheath. 5. Generally, there founded deep relationships between grain yield and each morphological characteristics of plant organ of elongating node-part as follows; Correlation coefficient between total area of 4 leaves (from flag to the fourth leaf) and grain yield was ${\gamma}$=0.666$^{**}$ In regard to the position of leaves, correlation coefficient values of flag, the second, the third and the fourth leaf were ${\gamma}$=0.659$^{**}$, ${\gamma}$=0.609$^{**}$, ${\gamma}$=0.464$^{*}$ and ${\gamma}$=0.523$^{*}$, respectively. Correlation coefficient between total weight of leaf blades and the grain yield was ${\gamma}$=0.678$^{**}$. In regard to the position of leaves, that of flag leaf was ${\gamma}$=0.691$^{**}$, and ${\gamma}$=0.654$^{**}$ for the second leaf, ${\gamma}$=0.570$^{**}$ for the third, and ${\gamma}$=0.544$^{**}$ for the fourth. Correlation between the weight of leaves (blade weight plus sheath weight) and the grain yield showed similar values. In the relationship between plant weight and grain yield there also was significant correlation, but with highly significant value only for the first node-part. There appeared correlation between total weight of leaf sheath and grain yield with the value of ${\gamma}$=0.572$^{**}$ and in regard to the position of each leaf sheath the values were ${\gamma}$=0.623$^{**}$ for the flag leaf, ${\gamma}$=0.486$^{**}$ for the second leaf, ${\gamma}$=0.513$^{**}$ for the third, ${\gamma}$=0.450$^{**}$ for the fourth. However, there was no significant correlation between culm weight and grain yield. 6. With respect to in gain yield, varietal differences in magnitude of leaf area, weight of leaf blade, leaf weight per unit area, weight of leaf sheath, culm weight, total leaf and stem weight were larger in the case of high yielding varieties and decreased in accordance with decreasing yield. And this tendency also was shown in the varietal differences of magnitude of each part. Variation in magnitude of each part for the leaf area, weight of leaf blade, culm weight was significantly small in high yielding varieties compared to low yielding varieties. 7. Plant constitutional ratio of each organ of the elongating node-part in term of weight magnitnde varied to som extent according to varieties indicating leaf blade 27.6%, leaf sheath 39.5%, culm 32.9% in the case of high yielding varieties, leaf blade 25.5%, leaf sheath 38.1%, culm 36.4% in the case of low yielding varieties, and medium yielding varieties showed intermadiate values. 8. Far higher values of the weight ration of leaf blade to culm and leaf sheath to culm were given to the high yielding varieties compared to low yielding varieties. And medium yielding varieties showed intermadiate values. II. Effects of application rate of nitrogen on the morphological characteristics of the elongating node-part, nitrogen content of leaf blade, and their relation with the grain yield of the rice were observed with 3 rice varieties; Shin No.2, Shirogane, and Jinheung varying application amounts of nitrogen as 8kg, 12kg and 16kg per 10 are. 1. As for the variation of morphological magnitude s affected by the amounts of nitrogen application, total leaf area (4 leaves from the flag leaf) increased to 16.5% at 12kg N plot, and about 30% at 16kg N polt compared to 8kg N plot and total weight of leaf blade also increased to similar extent, respectively, in contrast with weight of leaf sheath increasing 4.9% and 7.8%, respectively. However, the weight of culm decreased to 1.5% and 11.2%at the 12kg N plot and 16kg N plot, respectively, and these decreasing rate was noted at the nodes of lower part. 2. As for the verietal differences in variation of morphological magnitude as affected by the amount of nitrogen fertilization, leaf area coefficient value of variation of the total leaf area was 15.40% for Shin No. 2, 12.87% for Shirogane, and 10.99% for Jinheung. With respect to the position of nodes, the largest variation of leaf blade magnitude was observed at the fourth for Shin No. 2, the second for Shirogan, and flag leaf for Jinheung. And there also was an isotonic varietal difference in the weight of leaf blade. Variation in total culm weight showed varietal differences with the coefficient value of 7.72% for Shin No.2, 12.11% for Shirogane, and 0.94% for Jinheung. There also was varietal differences in the variation according to the position of nodes. 3. Variation of each elongating node-part related to the fertilization amount decreased with the increase of fertilization amount in the items of leaf area, weight of leaf sheath, culm weight, but weight of leaf sheath varied more at heavier fertilization than at others. 4. Constitutional ratio of each organ excluding head also varied with fertilization amount; constitutional ratio of leaf blade increased much with the increasing amount of fertilization in contrast with the response of culm eight. However, constitutional ration of the weight of leaf sheath was not much affected. 5. Lower value of the ration of leaf blade to culm was given to the 8kg N per 10 are plot, and the ratio of leaf blade to leaf sheath decreased with the increasing amount of fertilization in contrast with the increase in the ratio of leaf sheath to culm. however, the ration of leaf blade to culm plus leaf sheath decreased. 6. With the increase of nitrogen fertilization, leaf area, weight of leaf blade and leaf sheath increased. Accordingly, grin yield also increased to some extent. It was noted that culm weight was changed inversely to the changes in grain yield, but the degree of this variation varied with varietal characteristics. 7. Nitrogen content of leaves at heading and fruiting stage varied with the fertilization amount, and average nitrogen content of leaves of the varieties used 2.19%, 2.49% and 2.74% at the plot of 8kg N, and 12kg N and 16kg N per 10 are, respectively, at heading time, and 0.80%, 0.92% and 1.03% at each plot at fruiting stage. Thus, nitrogen content of leaves increased much with the increasing amount of fertilization, and higher value was given to the leaves on the higher position of elongating node-part. 8. There also was variation of nitrogen content of leaves in accordance with the varieties. However higher grain yield was obtained from the plants retaining higher nitrogen content in leaves at heading or fruiting stage.

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Changes of Distribution of Vascular Hydrophytes in the Nakdong River Estuary and Growth Dynamics of Schenoplectus triqueter, Waterfowl Food Plant (낙동강 하구의 수생관속식물의 분포 변화와 수금류(고니류)의 먹이식물인 세모고랭이의 성장 변화)

  • Kim, Gu-Yeon;Lee, Chan-Woo;Yoon, Hae-Soon;Joo, Gea-Jae
    • The Korean Journal of Ecology
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    • v.28 no.5
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    • pp.335-345
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    • 2005
  • A study on changes on the distribution of vascular hydrophytes and the growth pattern of Schenoplectus triqueter (Scirpus triqueter) was undertaken at the Nakdong River estuary from 2002 to 2004. The change was due to physical alteration of the estuary for the past 25 years. These plant species are the major food sources for winter waterfowl. A total of 32 species of vascular hydrophytes from 17 families were found in the West Nakdong River (freshwater), the main channel of Nakdong River (freshwater) and the Nakdong River Estuary (brackish water). After the construction of the barrage on the estuary in 1987, the number of hydrophytes has remarkably increased to 17 species (5 species in 1985) in the main channel of the River. In particular, a community of Eurale ferox was found at the backwater wetland of the Daejeo side of the main channel. The introduced species of Eichhornia crassipes and Pistia stratiotes that were epidemic in 2001 at West Nakdong River was not found any more. The other species such as Nymphoides indica, Myriophyllum spicatum, Ruppia spp. were rediscovered. The large area (about 1,300ha) of Zostera spp. was the main sources of food for swans, but disappeared because of direct and indirect impacts of reclamation in the River estuary. Currently, there remains a small patch of Zostera spp. and about 250ha of S. triqueter. Schenoplectus triqueter grew mostly between April-September and tuber formed, between September-October. The growth of S. triqueter up to $60\sim80cm$ in length was observed in 5 sites out of the 7 sites in brackish area. Tubers of S. triqueter were eaten by waterfowls such as swans as winter food. In five sites, tubers took $44\sim57%$ of total biomass in October. Tubers were found in deep layers; $5\sim15cm$ (9%), $15\sim25cm$ (28%), $25\sim40cm$ (55%), below 40cm $(6\sim7%)$. The distribution of vascular hydrophytes has remarkably changed in the Nakdong River Estuary due to the reclamation of the area. In order to determine the extent of changes of the distribution of these plants and the carrying capacity of the area for waterfowl, an intensive research is urgently needed.

Application of Science for Interpreting Archaeological Materials(III) Characterization of Some Western Asia Glass Vessels from South Mound of Hwangnamdaechong (고고자료의 자연과학 응용(III) 황남대총(남분)의 일부 서역계 유리제품에 대한 과학적 특성 분류)

  • Kang, Hyung Tae;Cho, Nam Chul
    • Korean Journal of Heritage: History & Science
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    • v.41 no.1
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    • pp.5-19
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    • 2008
  • Thirty six samples of Western asia glass vessel shards which were excavated from South Mound of Hwangnamdaechong were each measured for thickness, pore size and specific gravity and analyzed for ten major compositions and thirteen trace elements. The glass samples with colorless, greenish blue and dark purple blue were well classified by principal component analysis(PCA). All glass shards of Hwangnamdaechong belonged to Soda glass system ($Na_2O-CaO-SiO_2$) which have the range of 14~17% $Na_2O$ and 5~6% CaO. The corelation coefficients of (MgO, $K_2O$) and (MnO, CuO) showed above 0.90. The concentrations of thirteen trace elements apparently differentiated from colorless, greenish blue and dark blue glasses. We found that thirteen trace elements were very important indices for studying raw material of glass and the origin of glass making. Colorless glass : The specific gravity is $1.50{\pm}0.04$. Circle or oval circle pores are observed with regular direction in internal zone and the longest one is about 0.35 mm. The raw material of sodium must be the plant ash because sodium glasses contain HCLA(High CaO, Low $Al_2O_3$) and HMK(high MgO, high $K_2O$) and suggested to Sasanian glass. The total amount of coloring agent of colorless glass is below 1 % which is too small to attribute to the color. Greenish blue glass : The specific gravity is $1.58{\pm}0.04$. The fine pores which are 0.1~0.2mm are dispersed in internal zone. Sodium glasses are distributed to HCLA and HMK. Therefore the greenish blue glass also have used plant ash for raw material of sodium with the same as colorless glass. It was also suggested to the glass of Sasanian. The total amount of coloring agent of greenish blue glass is about 4% under the influence of working MnO, $Fe_2O_3$ and CuO. Dark purple blue glass : The specific gravity is $1.48{\pm}0.19$. There are rarely pores in internal zone. They are distributed to HCLA and LMK(Low MgO, Low $K_2O$) and suggested to Roman glass. The raw material of sodium is estimated to natron. The total amount of coloring agents of greenish blue is about 3% by $Fe_2O_3$ and CuO. These studies for western asia glass shards from South Mound of Hwangnamdaechong could be used in the future as the standard data which could be compared with those of other several graves in Korea and dispersed in foreign areas.