• Title/Summary/Keyword: middle layer

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Spatial Genetic Structure of Needle Fir(Abies holophylla Seedlings on the Forest Gap Within a Needle Fir Forest at Mt. Odae in Korea) (오대산(五臺山) 전나무림(林)의 숲틈에서 발생(發生)된 전나무 치수(稚樹)들의 공간적(空間的) 유전구조(遺傳構造))

  • Hong, Kyung-Nak;Choi, Young Cheol;Kang, Bum-Yong;Hong, Yong-Pyo
    • Journal of Korean Society of Forest Science
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    • v.90 no.4
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    • pp.565-572
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    • 2001
  • The spatial genetic structure of Needle fir(Abies holophylla Max.) seedlings on forest gap within a Needle fir forest at Mt. Odae in Korea was analyzed on the basis of ISSR(inter-simple sequence repeats) marker analysis. The gap size was $1,500m^2(50m{\times}30m)$, and we sampled 416 one- or two-year-old seedlings by 2m intervals. Some trees at the upper crown layer except Needle firs and all trees at the middle and lower crown layers were removed, and Needle firs at the upper crown layer showed very weak growth strength or to be withering to death. The results of spatial autocorrelation using 31 polymorphic ISSR markers revealed that it was genetically homogeneous within spatial distance of 15.6m and the randomness of genetic distribution was from 15.6m to 31.2m. The genetic patch size of seedlings in forest gap might be restricted by the density of mother trees, making allow for the average height of adult Needle firs, the seed dispersal area, and the average distance between adults. For the directionality of seedling distribution, we investigated the variography using 'genetic configuration' which was the value of configuration in Multidimensional Scaling by genetic distance. In directional variogram, the increment of spatial distance from East to West direction was inversely proportional to genetic homogeneity. We presumed that this anisotrophy of seedling distribution at this forest gap resulted from the directionality of seed dispersal rather than the difference of fecundity between mother trees or the microhabitat variation, taking the evenness of forest floor condition, a vast seed production and the random distribution of seedlings at the studied site into consideration.

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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).

Effect of Dietary Phytase on the Excreta Excretion of Laying Hens (사료 내 Phytase 첨가가 산란계의 분뇨 배설량에 미치는 영향)

  • Hong, E.C.;Na, S.H.;Yu, D.C.;Kim, H.K.;Park, M.N.;Jung, K.C.;Choo, H.J.;Park, H.D.;Chung, W.T.;HwangBo, J.
    • Korean Journal of Poultry Science
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    • v.36 no.3
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    • pp.257-264
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    • 2009
  • This work was conducted to investigate the effects of phytase on N and P excretion of laying hens excreta. Three hundred sixty ISA Brown layers were selected to investigate excreta excretion for 65 weeks and to investigate the effect of phytase on total excretion and N and P excretion of layers from 55 weeks. The experimental diets were fed the starter (0~5 wk), grower (5~12 wk), developer (12~16 wk), prelay diets (16 wk~first egg), layer diets for starting period (first egg~32 wk), middle (32~45 wk), finishing diets (45~55 wk, 55 wk~). Thirty ISA Brown layers were selected to investigate the effect of phytase supplementation on total N and P excretion of layers at 55 weeks and assigned randomly to 3 treatments groups (10 birds/treatment) and phytase was added to basal diets at 300 and 600 FTU/kg. Average body weight, feed intake, water intake, and excreta excretion were 1,622, 105.7, 187.2 and 124.7 g/bird/day, respectively. Excreta of birds fed phytase were DM (33.2, 31.2, 30.5 g/day), N (0.46, 0.42, 0.40 g/day) and P (0.51, 0.49, 0.48 g/day) and reduced as dietary phytase increased, Finally, dietary phyase can reduce the N and P excretion, but the amount of excreta was not different depending from the phytase addition in layers. This work investigated the N and P excretion of laying hens excreta and were considered that dietary phytase can reduce the N and P excretion for short period.

Basic Studies on the Consumptive Use of Water Required for Dry Field Crops (2) -Garlic and Cucumber- (밭작물소비수량에 관한 기초적 연구(II)-마늘 및 오이-)

  • 김철기;김진한;정하우;최홍규;권영헌
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.31 no.3
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    • pp.41-56
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    • 1989
  • The purpose of this study is to find out the basic data for irrigation plans of garlic and cucumber during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration and the maximum evapotranspiraton, optimum irrigation point, total readily available moisture, and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soil texture for split plot, and three levels ; irrigation points with pP 1.7-2.1, pP 2.2-2.5, pP 2.6-2.8, for garlic and those with pP 1.9, pF 2.3, pP 2.7, for cucumber, soil textures of silty clay, sandy loam and sandy soil for both garlic and cucumber, with two replications. The results obtained are summarized as follows 1.There was the highest significant correlation between the avapotranspiration of garlic and cucumber and the pan evaporation, beyond all other meteorological factors considered, as mentioned in the previous paper. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2.1/10 probability values of maximum total pan evaporation during growing period for garlic and cucumber were shown as 495.8mm and 406.8mm, respectively, and those of maximum ten day pan evaporation for garlic and cucumber, 63.8mm and 69.7mm, respectively. 3.The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage between the middle of May and the late of June(harvest period) for garlic, and at any stage of growing period for cucumber. 4.The magnitude of evapotranspiration and of its coefficient for garlic and cucumber was occurred in the order of pF 1.7-2.1>pF 2.2-2.5>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF2.7 respectively in aspect of irrigation point and of sandy loam>silty clay>sandy soil in aspect of soil texture for both garlic and cucumber. 5.The magnitude of leaf area index was shown in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 for garlic and of pF 1.9>pF 2.3>pF 2.7 for cucumber in aspect of irrigation point, and of sandy loam>sandy soil>silty clay in aspect of soil texture for both garlic and cucumber. 6.1/10 probability value of evapotranspiration and its coefficient during the growing period for garlic were shown as 391.7mm and 0.79 respectively, while those of cucumber, 423.lmm and 1.04 respectively. 7.The time the maximum evapotranspiration of garlic can be occurred is at the date of thirtieth before harvest period and the time for cucumber is presumed to be at the date of sixtieth to seventieth after transplanting, At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for garlic is presumed to be 65.lmm and 1.02 respectively, while those of cucumber, 94.8mm and 1.36 respectively. 8.In aspect of irrigation point, the weight of raw garlic and cucumber were increased in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF 2.7 respectively. Therefore, optimum irrigation point for garlic and cucumber is presumed to be pF 2.2-2.5 and pF 1.9 respectively, when the significance of yield between the different irrigation treatments is considered. 9.Except the mulching period of garlic that soil moisture extraction patterns were about the same, those of garlic and cucumber have shown that maximum extraction rate exists at 7cm deep layer at the beginning stage after removing mulching for garlic and at the beginning stage of growth for cucumber and that extraction rates of 21cm to 35cm deep layer are increased as getting closer to the late stage of growth. 10.Total readily available moisture of garlic in silty clay, sandy loam, sandy soil become to be 18.71-24.96mm, 19.08-25.43mm, 10.35- 13.80mm respctively on the basis of the optimum irrigation point with pF 2.2-2.5, while that of cucumber, 11.8lmm, 12.03mm, 6.39mm respectively on the basis of the optimum irrigation point with pF 1.9. 11.The intervals of irrigation date of garlic and cucumber at the growth stage of maximum consumptive use become to be about three and a half days and one and a half days respectively, on the basis of each optimum irrgation point.

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Tidal and Sub-tidal Current Characteristics in the Central part of Chunsu Bay, Yellow Sea, Korea during the Summer Season (서해 천수만 중앙부의 하계 조류/비조류 특성)

  • Jung, Kwang Young;Ro, Young Jae;Kim, Baek Jin
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.2
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    • pp.53-64
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    • 2013
  • This study analyzed the ADCP records along with wind by KMA and discharge records at Seosan A-, B-district tide embankment by KRC for 33 days obtained in the Chunsu Bay, Yellow Sea, Korea spanning from July 29 to August 30, 2010. Various analyses include descriptive statistics, harmonic analysis of tidal constituents, spectra and coherence, complex correlation, progressive vector diagram and cumulative curves to understand the tidal and sub-tidal current characteristics caused by local wind and discharge effect. Observed current speed ranges from -30 to 40 (cm/sec), with standard deviation from 1.7 (cm/sec) at bottom to 18.7 (cm/sec) at surface. According to the harmonic analysis results, the tidal current direction show NNW-SSE. The magnitudes of semi-major axes range from 9.4 to 14.8 (cm/sec) for M2 harmonic constituent and from 4.4 to 7.0 (cm/sec) for S2, respectively. And the magnitudes of semi-minor axes range from 0.1 to 0.5 (cm/sec) for M2 and from 0.4 to 1.4 (cm/sec) for S2, respectively. In the spectral analysis results in the frequency domain, we found 3~6 significant spectral peaks for band-passed wind and residual current of all depth. These peak periods represent various periodicities ranging from 2 to 8 (days). In the coherency analysis results between band-passed wind and residual current of all depth, several significant coherencies could be resolved in 3~5 periodicities within 2.8 (days). Highest coherency peak occurred at 4.6 (day) with 1.2-day phase lag of discharge to band-passed residual current. The progressive vector of wind and residual current travelled to northward at all layers, and the travel distance at middle layer was greater than surface layer distance. The Northward residual current was caused by a seasonal southern wind, and the density-driven current formed by fresh water input effected southward residual current. The sub-tidal current characteristics is determined by seasonal wind force and fresh water inflow in the Chunsu Bay, Yellow Sea, Korea.

A Study on the Restoration of the Wangheungsa Temple's Wooden Pagoda (왕흥사 목탑의 복원 연구)

  • Kim, Kyeong-Pyo;Sung, Sang-Mo
    • Journal of architectural history
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    • v.19 no.3
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    • pp.7-29
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    • 2010
  • The form of the Wangheungsa Temple's wooden pagoda site is that of the traditional form of the wooden pagodas constructed during the Baekjae Period. Likewise, it is an important ruin for conducting research on the form and type of the wooden pagodas constructed during the Baekjae Period. In particular, the method used for the installation of the central pillar's cornerstone is a new technique. The purpose of this research is to restore the ruin of the Wangheungsa Temple's wooden pagoda of the Baekjae Period that remains at the Wangheungsa Temple's wooden pagoda site. Until now, research conducted on the wooden pagoda took place mostly centered on the Hwangryongsa Temple's wooden pagoda. Meanwhile, the reality concerning Baekjae's wooden pagoda is one in which there were not many parallel cases pertain to the design for restoration. This research paper wants to conduct academic examination of the Wangheungsa Temple's wooden pagoda to organize the intention of design and design process in a simple manner. This research included review of the Baekjae Period's wooden pagoda related ruins and the review of the existing wooden pagoda ruin to analyze the wooden pagoda construction technique of the era. Then, current status of the Wangheungsa Temple's wooden pagoda site is identified to define the characteristics of the wooden pagoda, and to set up the layout format and the measure to estimate the size of the wooden pagoda in order to design each part. Ultimately, techniques and formats used for the restoration of the wooden pagoda were aligned with the wooden pagoda of the Baekjae Period. Basically, conditions that can be traced from the current status of the Wangheungsa Temple site excavation using the primary standards as the standard. Wangheungsa Temple's wooden pagoda was designed into the wooden pagoda of the Baekjae's prosperity phase. The plane was formed into $3{\times}3$ compartments to design into three tier pagoda. The height was decided by factoring in the distance between the East-West corridors, size of the compartment in the middle, and the view that is visible from above the terrace when entering into the waterway. Basically, the origin of the wooden structure format is based on the Goguryeo style, but also the linkage with China's southern regional styles and Japan's ancient wooden pagoda methods was factored in. As for the format of the central pillar, it looks as if the column that was erected after digging the ground was used when setting up the columns in the beginning. During the actual construction work of the wooden pagoda, central pillar looks as if it was erected by setting up the cornerstone on the ground. The reason that the reclaimed part of pillar that use the underground central cornerstone as the support was not utilized, was because the Eccentric Load of the central pillar's cornerstone was factored in the state of the layers of soil piled up one layer at a time that is repeated with the yellow clay and sandy clay and the yellow clay that were formed separately with the $80cm{\times}80cm$ angle at the upper part of the central pillar's cornerstone was factored in as well. Thus, it was presumed that the central pillar was erected in the actual design using the ground style format. It is possible to presume the cases in which the reclaimed part of pillar were used when constructed for the first time, but in which central pillar was installed later on, after the supplementary materials of the underground column is corroded. In this case, however, technique in which soil is piled up one layer at a time to lay down the foundation of a building structure cannot be the method used in that period, and the reclamation cannot fill up using the $80cm{\times}80cm$ angle. Thus, it was presumed that the layers of soil for building structure's foundation was solidified properly on top of the central pillar's cornerstone when the first wooden pagoda construction work was taking place, and that the ground style central pillar was erected on its upper part by placing the cornerstone once again. Wangheungsa Temple's wooden pagoda is significant from the structure development aspect of the Korean wooden pagodas along with the Hwangryongsa Temple's wooden pagoda. Wangheungsa Temple's wooden pagoda construction technique which was developed during the prosperity phase of the Baekjae Period is presumed to have served as a role model for the construction of the Iksan Mireuksa Temple's wooden pagoda and Hwangryongsa Temple's wooden pagoda. With the plan to complement the work further by excavating more, the basic wooden pagoda model was set up for this research. Wangheungsa Temple's wooden pagoda was constructed as at the Baekjae Kingdom wide initiative, and it was the starting point for the construction of superb pagoda using state of the art construction techniques of the era during the Baekjae's prosperous years, amidst the utmost interest of all the Baekjae populace. Starting out from its inherent nature of enshrining Sakyamuni's ashes, it served as the model that represented the unity of all the Baekjae populace and the spirit of the Baekjae people. It interpreted these in the most mature manner on the Korean peninsula at the time.

Effect of Protein Level and Dietary Germanium Biotite on Egg Production, Egg Quality and Fecal Volatile Fatty Acid in Laying Hens (단백질 수준과 게르마늄 흑운모의 첨가가 산란생산성, 계란품질 및 분내 휘발성 지방산에 미치는 영향)

  • Lee, Won-Baek;Kim, In-Ho;Hong, Jong-Uk;Kwon, O-Seok;Min, Byeong-Jun;Son, Gyeong-Seung;Jung, Yeon-Kwon
    • Korean Journal of Poultry Science
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    • v.30 no.4
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    • pp.275-280
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    • 2003
  • This study conducted to investigate the effect of dietary germanium biotite by protein level in laying hen diets. One hundred forty four, 51 weeks old ISA brown commercial layer, were used in experiment. Dietary treatments were 1) low protein diet(LPD), 2) high protein diet(HPD), 3) LPD-GB(LPD + 1.0% germanium biotite) and 4) HPD-GB(HPD + 1.0% germanium biotite). Henday egg production tended to be increased as the concentration of protein in diets increased with significant difference(P<0.01). Egg weight tended to decrease by increasing of supplementation germanium biotite in the diets(P<0.01). Egg shell breaking strength was not influenced by germanium biotite supplementation(P>0.05). Large band of egg decrease as increasing of supplementation germanium biotite in the diets(P<0.02). Sharp and middle band of egg were not influenced by germanium biotite supplementation. Egg yolk index tended to decrease as increasing of supplementation germanium biotite in the diets(p<0.01). Fecal propionic acid(P<0.01) and butyric acid(P<0.03) were decrease as the concentration of germanium biotite in the diet was increased. Also, butyric acid increased as the concentration of protein in diets increased with significant difference(P<0.02). Supplementation germanium biotite in the diet reduced the fecal acetic acid(P<0.01). Fecal $NH_3$-N of hens fed HPD-GB diet was decreased(P<0.05) compared to that LPD-GB diet. In conclusion, germanium biotite supplementation to layer diets can reduce fecal volatile fatty acid compabebts.

Environmental Change of High Moor in Mt. Dae-Am of Korean Peninsula (대암산 고층습원의 환경변천)

  • Yoshioka, Takahito;Kang, Sang-Joon
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.45-53
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    • 2005
  • The environmental change of Yong-nup in Mt. Dae-Am, which is located at the northern part of Kangwon-Do, Korea, was assesed with peat sedimentary carbon and nitrogen isotope analysis. The surface layer of the peat (0 ${\sim}$ 5 cm) was 190 year BP, and the middle layers (30 ${\sim}$ 35 cm and 50 ${\sim}$ 55 cm) were 870 year BP and 1900 year BP, respectively. Bulk sedimentation rate was estimated to be about 0.4 mm $year^{-1}$ for 0 cm to 30 cm and 0.15 mm $year^{-1}$ for 35 cm to 50 cm. The $^{14}C$ age of the bottom sediment (75 ${\sim}$ 80 cm) collected and measured in this study was about 1900 year BP, although it was measured that the $^{14}C$ of the lowest bottom sediment in Yong-nup was 4105 ${\pm}$ 175 year BP (GX-23200). Since the $^{14}C$ ages for 50 ${\sim}$ 55 cm and 75 ${\sim}$ 80 cm layers were almost the same as 1890 ${\pm}$ 80 fear BP (NUTA 5364) and 1850 ${\pm}$ 90 year BP (NUTA 5462), respectively, we have estimated that the deep layers (55 ${\sim}$ 80 cm) in the high moor were the original forest soil. The low organic C and N contents in the deeper layers supported the inference. The sediment of 50 ${\sim}$ 55 cm layer contains much sandy material and showed very low organic content, suggesting the erosion (flooding) from the surrounding area. In this context, the Yong-nup, high moor, of Mt. Dae-Am, might have developed to the sampling site at about 1900 year BP. The ${\delta}^{13}C$ values of organic carbon and the ${\delta}^{15}N$ values of total nitrogen in the peat sediments fluctuated with the depths. The profile of ${\delta}^{13}C$ may indicate that the Yong-nup of Mt. Dae-Am have experienced the dry-wet and cool-warm period cycles during the development of the high moor. The ${\delta}^{15}N$ may indicate that the nitrogen cycling in the Yong-nup have changed from the closed (regeneration depending) system to the open (rain $NO_3\;^-$ and $N_2$ fixation depending) system during the development of the high moor.

Plankton Community Response to Physico-Chemical Forcing in the Ulleung Basin, East Sea during Summer 2008 (2008년 하계 울릉분지에서 관측된 물리·화학적 외압에 대한 플랑크톤 군집의 반응)

  • Rho, Tae-Keun;Kim, Yun-Bae;Park, Jeong-In;Lee, Yong-Woo;Im, Dong-Hoon;Kang, Dong-Jin;Lee, Tong-Sup;Yoon, Seung-Tae;Kim, Tae-Hoon;Kwak, Jung-Hyun;Park, Hyun-Je;Jeong, Man-Ki;Chang, Kyung-Il;Kang, Chang-Keun;Suh, Hae-Lip;Park, Myung-Won
    • Ocean and Polar Research
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    • v.32 no.3
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    • pp.269-289
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    • 2010
  • In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

Community Structure of Forest Vegetation in Mt. Geumsusan belong to Woraksan National Park (월악산국립공원 금수산 산림식생의 군집구조)

  • Kim, Ho-Jin;Shin, Jae-Kwon;Lee, Cheol-Ho;Yun, Chung-Weon
    • Korean Journal of Environment and Ecology
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    • v.31 no.2
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    • pp.202-219
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    • 2017
  • The purpose of this study was to analyze the community structure of forest vegetation in Mt. Geumsusan belong to Woraksan National Park for providing basic information of ecological management. Data were collected by 41 plots from June to November in 2016 using Z-M phytosociology method, which was analyzed with vegetation types, mean importance value and coincidence method. As the results, the forest vegetation was classified into Quercus mongolica community group including Cornus controversa community, Castanea crenata community(Vegetation unit 3), Quercus variabilis community(Vegetation unit 4) and Q. mongolica community(Vegetation unit 5). C. controversa community was divided into two groups such as Ulmus davidiana var. japonica group(Vegetation unit 1) and Parthenocissus tricuspidata group(Vegetation unit 2). Mean importance percentage of vegetation unit 1 was showing Fraxinus rhynchophylla 14.9%, Morus bombycis 8.7% and Acer pictum subsp. mono 8.3%, that of unit 2 was Larix kaempferi 23.2%, C. controversa 20.1% and P. tricuspidata 6.5%, that of unit 3 was Q. mongolica 15.8%, C. crenata 13.4% and F. rhynchophylla 9.8%, that of unit 4 was Q. mongolica 26.6%, Q. variabilis 20.8% and Pinus densiflora 16.7%, that of unit 5 was Q. mongolica 48.3%, Styrax obassia 7.5%, F. rhynchophylla 5.3% in the order, respectively. Each vegetation unit was classified with dependance on environmental factors as 700m of altitude, $20^{\circ}$ of slope degree, middle slope of topography, 20% of bare rock, 30 taxa of present species, 80% of tree layer coverage rate and 20m of tree layer height. In conclusion, it was preferentially considered that development of peculiar and specific management methods with vegetation unit classified above should be needed for ecological and sustainable forest vegetation management.