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Analysis of Optimal Pathways for Terrestrial LiDAR Scanning for the Establishment of Digital Inventory of Forest Resources (디지털 산림자원정보 구축을 위한 최적의 지상LiDAR 스캔 경로 분석)

  • Ko, Chi-Ung;Yim, Jong-Su;Kim, Dong-Geun;Kang, Jin-Taek
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.245-256
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    • 2021
  • This study was conducted to identify the applicability of a LiDAR sensor to forest resources inventories by comparing data on a tree's position, height, and DBH obtained by the sensor with those by existing forest inventory methods, for the tree species of Criptomeria japonica in Jeolmul forest in Jeju, South Korea. To this end, a backpack personal LiDAR (Greenvalley International, Model D50) was employed. To facilitate the process of the data collection, patterns of collecting the data by the sensor were divided into seven ones, considering the density of sample plots and the work efficiency. Then, the accuracy of estimating the variables of each tree was assessed. The amount of time spent on acquiring and processing the data by each method was compared to evaluate the efficiency. The findings showed that the rate of detecting standing trees by the LiDAR was 100%. Also, the high statistical accuracy was observed in both Pattern 5 (DBH: RMSE 1.07 cm, Bias -0.79 cm, Height: RMSE 0.95 m, Bias -3.2 m), and Pattern 7 (DBH: RMSE 1.18 cm, Bias -0.82 cm, Height: RMSE 1.13 m, Bias -2.62 m), compared to the results drawn in the typical inventory manner. Concerning the time issue, 115 to 135 minutes per 1ha were taken to process the data by utilizing the LiDAR, while 375 to 1,115 spent in the existing way, proving the higher efficiency of the device. It can thus be concluded that using a backpack personal LiDAR helps increase efficiency in conducting a forest resources inventory in an planted coniferous forest with understory vegetation, implying a need for further research in a variety of forests.

Seed Germination, Seedling Growth and Biomass Production of Eucommia ulmoides (두충(杜冲)나무의 종자발아(種子發芽), 묘목생장(苗木生長) 및 물질생산(物質生產))

  • Goo, Gwan Hyo;Youn, Ki Sik;Lee, Kang Young
    • Journal of Korean Society of Forest Science
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    • v.80 no.2
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    • pp.202-209
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    • 1991
  • This study was carried out to examine seed germination, seedling growth, and biomass production of Eucommia ulmoides. The results were summarized as follows ; 1. Cold moist stratification at a refrigerator showed 60.3% of seed germination, which is the most effective among pretreatment methods. 2. In case of 1-0 seedlings, sixty seedlings per $1m^2$ was the most appropriate density, and the growth quality of seedlings differed significantly among densities. 3. Height growth showed continuous growth pattern and the maximum growth was shown during the period 21 June to 20 July, which corresponds 32.7% of total annual growth. 4. As tree age and DBH increased, the production of bark and leaf increased, however, its increment rate remarkably dropped down after ten years. 5. When tree age was ten years, the rate of bark volume showed the maximum value, 12.42%. 6. Dry weight of barks and leaves and bark volume were positively related to the growth of DBH and height. 7. As tree age increased, leaf area decreased, but the number of leaves increased.

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The Variations of Stratospheric Ozone over the Korean Peninsula 1985~2009 (한반도 상공의 오존층 변화 1985~2009)

  • Park, Sang Seo;Kim, Jhoon;Cho, Nayeong;Lee, Yun Gon;Cho, Hi Ku
    • Atmosphere
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    • v.21 no.4
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    • pp.349-359
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    • 2011
  • The climatology in stratospheric ozone over the Korean Peninsula, presented in previous studies (e.g., Cho et al., 2003; Kim et al., 2005), is updated by using daily and monthly data from satellite and ground-based data through December 2009. In addition, long-term satellite data [Total Ozone Mapping Spectrometer (TOMS), Ozone Monitoring Instrument (OMI), 1979~2009] have been also analyzed in order to deduce the spatial distributions and temporal variations of the global total ozone. The global average of total ozone (1979~2009) is 298 DU which shows a minimum of about 244 DU in equatorial latitudes and increases poleward in both hemispheres to a maximum of about 391 DU in Okhotsk region. The recent period, from 2006 to 2009, shows reduction in total ozone by 6% relative to the values for the pre-1980s (1979~1982). The long-term trends were estimated by using a multiple linear regression model (e.g., WMO, 1999; Cho et al., 2003) including explanatory variables for the seasonal variation, Quasi-Biennial Oscillation (QBO) and solar cycle over three different time intervals: a whole interval from 1979 to 2009, the former interval from 1979 to 1992, and the later interval from 1993 to 2009 with a turnaround point of deep minimum in 1993 is related to the effect of Mt. Pinatubo eruption. The global trend shows -0.93% $decade^{-1}$ for the whole interval, whereas the former and the later interval trends amount to -2.59% $decade^{-1}$ and +0.95% $decade^{-1}$, respectively. Therefore, the long-term total ozone variations indicate that there are positive trends showing a recovery sign of the ozone layer in both North/South hemispheres since around 1993. Annual mean total ozone (1985~2009) is distributed from 298 DU for Jeju ($33.52^{\circ}N$) to 352 DU for Unggi ($42.32^{\circ}N$) in almost zonally symmetric pattern over the Korean Peninsula, with the latitudinal gradient of 6 DU $degree^{-1}$. It is apparent that seasonal variability of total ozone increases from Jeju toward Unggi. The annual mean total ozone for Seoul shows 323 DU, with the maximum of 359 DU in March and the minimum of 291 DU in October. It is found that the day to day variability in total ozone exhibits annual mean of 5.7% in increase and -5.2% in decrease. The variability as large as 38.4% in increase and 30.3% in decrease has been observed, respectively. The long-term trend analysis (e.g., WMO, 1999) of monthly total ozone data (1985~2009) merged by satellite and ground-based measurements over the Korean Peninsula shows increase of 1.27% $decade^{-1}$ to 0.80% $decade^{-1}$ from Jeju to Unggi, respectively, showing systematic decrease of the trend magnitude with latitude. This study also presents a new analysis of ozone density and trends in the vertical distribution of ozone for Seoul with data up to the end of 2009. The mean vertical distributions of ozone show that the maximum value of the ozone density is 16.5 DU $km^{-1}$ in the middle stratospheric layer between 24 km and 28 km. About 90.0% and 71.5% of total ozone are found in the troposphere and in the stratosphere between 15 and 33 km, respectively. The trend analysis reconfirms the previous results of significant positive ozone trend, of up to 5% $decade^{-1}$, in the troposphere and the lower stratosphere (0~24 km), with negative trend, of up to -5% $decade^{-1}$, in the stratosphere (24~38 km). In addition, the Umkehr data show a positive trend of about 3% $decade^{-1}$ in the upper stratosphere (38~48 km).

Seasonal Prevalence of the Vector Mosquitoes of Japanese Encephalitis Virus in Kyungpook Province, Korea (경북지역에서의 일본뇌염 매개모기에 출현 소장)

  • 주종윤;화전의인
    • Parasites, Hosts and Diseases
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    • v.23 no.1
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    • pp.139-150
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    • 1985
  • In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

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Community Structure of Subtidal Macrobenthos in Hampyung Bay during Autumn in 1997, Southwest Coast of Korea (한국 서남해역 함평만 조하대의 가을철 저서동물 군집구조)

  • LIM Hyun-Sig;CHOI Jin-Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.4
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    • pp.327-339
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    • 2001
  • Community structure of macrobenthos was studied at forty one stations of Hampyung Bay, southwest coast of Korea. Three replicate sediment samples were taken at each station in October 1997, using a van Veen grab (surface area $0.1\;m^2$). The types of surface sediment in the sampling area were muddy sandy gravel between bay mouth and bay proper, and gravelly sandy mud between bay proper and inner bay stations. The particulate organic carbon content in the surface sediment was $0.23\sim0.69\%\;(0.44\pm0.10\%)$. A total of 168 species collected during the study period is composed of 58 of polychaetes, 54 of crustaceans, 34 of molluscs and 22 of miscellaneous. The former two taxa together were accounted for $66.6\%$ of the total number of species. The mean density was $1,168 ind./m^2$, comprising $684 ind./m^2$of molluscs ($58.6\%$), $381 ind./m^2$of polychaetes ($32.6\%$), and $90 ind./m^2$of crustaceans ($13.2\%$). The mean biomass was $358.65 g/m^2$, which is consisted of $302.97 g/m^2$of molluscs ($84.5\%$), $24.20 g/m^2$of echinoderms ($6.7\%$), and $19.16 g/m^2$of crustaceans ($5.4\%$). Major dominant species at the inner stations of the study area was Ruditapes philippinarum with a density of $520ind./m^2$($44.5\%$), and Lumbrineris lontifolia with $183ind./m^2$($15.7\%$), while that at bay mouth stations Pitar indecoroides with $56ind./m^2$. Reticunassa festiva, Heteromastus sp., Praxillella affinis, Chone sp. and Tharyx sp. were at from all stations. Based on the cluster analysis, the macrobenthic community in the bay was classified into five station groups depending on sediment types: Group A, a high gravel content in the sediment; Group B, stations with high mud content from bay mouth to bay proper, Group C, stations with fine and poorly sorted sediment from bay proper to the inner bay. The distribution pattern of the number of species, abundance and biomass is discussed in relation to environmental variables.

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Relationship between Expression of XIAP Protein in Operable Non-small Cell Lung Carcinomas and Apoptosis Index and Postoperative Prognosis (비소세포폐암조직에서 XIAP 발현과 고사지수 및 수술 후 예후와의 관계)

  • Kim, Sang Hyun;Lee, Chang Hun;Sol, Mee Young;Song, Jin Mi;Lee, Jong Hyub;Lee, Min Ki;Kim, Jong Min
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.5
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    • pp.480-489
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    • 2005
  • Background : Dysregulation of apoptosis plays an important role in carcinogenesis, tumor progression, and resistance to chemotherapy. X-linked inhibitor of apoptosis (XIAP) is considered to be the most potent caspase inhibitor of all known IAP (inhibitor of apoptosis) family members. This study was designed to assess the pattern of expression and the prognostic value of XIAP in radically resected non-small cell lung carcinoma (NSCLC) patients. Method : The expression of XIAP and its relationship with clinicopathologic parameters (patient age, TNM stage, TNM-pT, TNM-pN, histologic type, VEGF expression, microvessel density, PCNA index) and overall survival were analysed with formalin-fixed, paraffin-embedded blocks from eighty cases of NSCLC. In addition, the apoptotic index (AI) was also assessed. Results : In a regard to histologic type, squamous cell carcinoma (SCC) showed XIAP expression in 91.3%(42/46) and adenocarcinoma (AC) in 61.8%(21/34). The difference was significant(p=0.001). There was no correlation between XIAP expression and other parameters. In the group of AC, XIAP expression showed the signifcant correlation with older age group ${\geq}58years$ and VEGF expression(p=0.028, p=0.014, respectively). The AI in the group with or without XIAP expression were $2.5{\pm}4.9%$ and $18.5{\pm}28.9%$, respectively(p=0.001). Both groups just aforementioned showed no significant difference in median survival time (42.5 months, 29.8 months, respectively). Conclusion : This study suggests that the XIAP expression in NSCLCs could have relation to inhibition of apoptosis, and show differential expression according to histologic type. However, its prognostic role during the progression of NSCLC needs to be further defined.

Dynamics of Phytoplankton and Zooplankton of a Shallow Eutrophic Lake (lake llgam) (수심이 얕은 부영양 인공호(일감호)의 동 ${\cdot}$ 식물플랑크톤 동태학)

  • Kim, Ho-Sub;Park, Je-Chul;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.286-294
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    • 2003
  • This study was attempted to understand seasonal dynamics of phyto- and zooplankton communities in shallow, eutrophic Lake llgam and to compare them with the PEG (Plankton Ecology Group) model. Seasonal succession pattern of phytoplankton community was similar to PEG model as Chlorophyceae and Baciliphyceae increase during spring and autumn fellowed by increase of Cyanophyceae. However, based on the cell density and biomass, a dominant phytoplankton community differed with PEG model: Cyanophyceae had been a dominant community throughout a year, except for ice-cover period during which Chlorophyceae was a dominant group. In spring, when ice melted and dissolved nutrients in water column increased, the increase of Chlorophyceae occurred: when nutrients (DIN and DIP) rapidly decreased, Cyanophyceae increase occurred. Microcystis, Oscillatoria, Lyngbya, Merismopedia were maior dominant species of Cyanophyceae and their cell density and/or biomass was the highest in October 2000 (12.9${\pm}$5.8${\times}10^5$ cells/ml, 3.5${\pm}$0.9${\times}10^3{\mu}gC/l$). Cyanophyceae biomass showed positive relationship with chlorophyll a ($r^2$ = 0.71,P< 0.001) and TP concentration ($r^2$ = 0.62, P< 0.001). Small-sized rotifers such as Keratella cochlearis, increased between March and May when Chlorophyceae increased. Both high standing crop of copepods and cladocerans, such as Diaphanosoma brachyrum and Bosmina longirostris occurred between June and September accompanied with the increase of Dinophyceae and Bacillariophyceae. There was no evidence that clear-water phase was caused by zooplankton grazing. The diversity and evenness index of phyto- and/or zooplankton increased with chlorophyll a concentration. These results suggest zooplankton grazing and limiting nutrient deficiency could lead to change of phytoplankton biomass, but not the phytoplankton community in Lake llgam.

Annual Occurrent Pattern of Scirtothrips dorsalis (Thysanoptera: Thripidae) on Citrus Trees and Surrounding Host Plants (감귤원과 그 주변 기주식물에서 볼록총채벌레의 연중발생 양상)

  • Song, Jeong Heub;Kim, Chang Seog;Yang, Young Taek;Hong, Soon Yeong;Lee, Shin Chan
    • Korean journal of applied entomology
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    • v.52 no.3
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    • pp.185-191
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    • 2013
  • The damage of citrus by Scirtothrips dorsalis Hood appears to have increased since 2007 in Jeju, although the characteristics of seasonal abundance are not clear. This study was conducted to investigate the relationship between host plants and the seasonal abundance of S. dorsalis, observing plants distributed around citrus orchards. The host plants of S. dorsalis surrounding citrus orchards were determined to include 32 families, 54 species: 39 woody plant species and 15 herbaceous plant species. The host plants which related to the occurrence of 1st generation of S. dorsalis were Lonicera japonica, Clematis apiifolia, Hedera rhombea, and Viburnum awabuki. The occurrence of 1st generation S. dorsalis was estimated to be due to overwintered female adults having laid eggs into those plants from late March to early April, and the new adults having emerged from late April to late May. The host plants which were associated with fruit damage of citrus were Mallotus japonicus, and Camellia japonica, as well as creeping plants such as Clematis apiifolia, Paederia scandens and Cayratia japonica. The adult phase density of S. dorsalis caught on yellow-color sticky traps placed on the citrus trees on the edge of the citrus orchard. S. dorsalis were predominantly 3rd generation from late of June to early of July, and 6th generation from late of August to early of September, and their numbers were directly related to the degree of damage caused to the citrus fruit. The density of S. dorsalis depended on the number of new growing shoots of host plants, which indicated that the immigration of adults of S. dorsalis to the citrus was based in the suitability of host plants surrounding the orchards.

Analysis of hybridity of Asplenium castaneo-viride Baker (거미꼬리고사리의 잡종성 분석)

  • Kwon, Yong Ju;Kim, Chul Hwan;Ahn, Jin Kap;Sun, Byung-Yun
    • Korean Journal of Plant Taxonomy
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    • v.39 no.1
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    • pp.12-23
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    • 2009
  • To verify hybridity of Asplenium castaneo-viride, external morphology, spore morphology, anatomy and chromosomes of the species and of the two presumed parental species, A. incisum and A. ruprechtii, were examined. A. castaneo-viride usually had 1-pinnately divided frond. However, some individuals had almost simple fronds with pinnatisect basal parts similar to A. ruprechtii, while others had fronds similar to A. incisum in having oblanceolate blades and basal pinnae with triangular, 2-3 lobed apices. On the surface of the spores, sculpturing consisted of folds that were usually prominent; forming long wings, and irregular or incomplete reticulation. However, reticulation patterns varied among species. A. castaneo-viride showed a wide range of variation from sparse to dense patterns, whereas A. incisum showed only from sparse to intermediate patterns. A. ruprechtii showed from intermediate to dense patterns. The spore size of A. castaneo-viride was $54.63{\mu}m$, larger than other two species ($47.81{\mu}m$ in A. incisum and $44.22{\mu}m$ in A. ruprechtii). The level of undulation of epidermal cell wall was also different. A. incisum had the most shallowly undulated wall, and A. castaneo-viride had a pattern intermediate between the two presumed parental species. This same patterns was recognized in the density of stomata. The density of $45.91/mm^2$ in A. castaneo-viride was intermediate between the two presumed parental species ($67.00/mm^2$ in A. incisum, and $37.86/mm^2$ in A. ruprechtii). Chromosome number was constant (2x =2n = 72) as in A. incisum and A. ruprechtii. However, A. castaneo-viride showed a different ploidy level. The populations of Mt. Mai (Jeonbuk province) and Mt. Duryun (Jeonnam province) were diploid (2n = 72) which is a new record for this taxon, whereas the population of Mt. Buram (Seoul) was tetraploid (2n = 144). Conclusively, A. castaneo-viride was revealed to be a hybrid of A. ruprechtii and A. incisum based on evidence involving leaves, spores, epidermal cells, stomata and chromosome number.

Effects of Alternative Crops Cultivation on Soil Physico-chemical Characteristics and Crop Yield in Paddy Fields (논에서 벼 대체작물 재배가 토양 물리화학성과 작물 수량에 미치는 효과)

  • Han, Kyunghwa;Cho, Hyunjun;Cho, Heerae;Lee, Hyubsung;Ok, Junghun;Seo, Mijin;Jung, Kangho;Zhang, Yongseon;Seo, Youngho
    • Korean Journal of Environmental Agriculture
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    • v.36 no.2
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    • pp.67-72
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    • 2017
  • BACKGROUND:Cultivation of alternative crops in paddy fields is necessary because of the decrease in rice consumption and the increase in excess stock of rice. The study was conducted to investigate the effects of alternative crops cultivation in paddy fields on soil physico-chemical characteristics and crop yield. METHODS AND RESULTS: Soybean (Glycine max), red-clover (Trifolium pratense), and water convolvulus (Ipomoea aquatica) were selected for alternative crops in the first and/or second year and rice was planted in the third year. When alternative crops were cultivated in the previous year, soil bulk density, soil hardness, and water content were lower than those for rice cultivation. Water-depth decreasing rate and aggregate content were greater for the upland-upland-paddy cropping system than upland-paddy-paddy cropping system. Cultivation of red-clover and water convolvulus for two years resulted in the high soil organic matter content. In the third year, available phosphate, exchangeable potassium, and soil cation exchange capacity were relatively high when soybean was cultivated in the previous year. In the first year, water convolvulus cultivation showed greater productivity than red-clover cultivation while the opposite pattern was found in the second year. Rice yield in the third year was greater for soybean or red-clover as a previous crop than for water convolvulus as a previous crop. CONCLUSION: The results suggest that cultivation of alternative crops in paddy fields can improve soil physical properties including bulk density, hardness, water content, and aggregate content as well as rice productivity.