• Journal of Korean Society of Forest Science
• /
• v.83 no.3
• /
• pp.372-379
• /
• 1994

Timber harvesting impacts on soil microbial populations and respiration rates were examined in naturally regenerating trembling aspen(Populus tremuloides Michx.) stands on two contrasting soils, an Omega loamy sand (sandy mixed, frigid Typic Udipsamment) and an Ontonagon clay loam (very fine, mixed Glossic Eutroboralf). Five timber harvesting disturbances were simulated during winter of 1990 and spring of 1991, including commercial whole-tree harvesting(CWH), winter logging trail+CWH, logging slash removal+CWH(LSR), forest floor removal+LSR(FFR), and spring compaction+FFR. Regardless of soil types, total soil respiration rates of each stand decreased slightly or remained the same after harvesting while microbial population increased progressively during the first two years following harvesting. Microbial populations increased more rapidly and constantly at the sandy site than at the clayey site, which may indicate that the soil physical and chemical conditions changed more drastically for microbial activity following timber harvesting at the sandy site than at the clayey site. However, two kinds of treatment applications-three levels of organic matter removal and two levels of compaction-did not result in significant differences in microbial population or total soil respiration rate at each site during the first two post-harvest years. Total soil respiration of the aspen stands, sum of root respiration and microbial respiration, was a poor index for the microbial activity in this study because aspen kept an active root system for the successive root-sprouts even after harvesting, which resulted in a large portion of root respiration in total respiration.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.30 no.3
• /
• pp.340-348
• /
• 1997

Sledge net samples were taken over the neap and spring tide cycles in January 1993 from the bottom and surface of 1 m depth and at the water's edge in the sandy shore surf zone of Dolsando, southern Korea. Zonation pattern of three dominant gammarid amphipods was compared. The amphipods were more abundant on the bottom and at water's edge than in the surface. Average densities at both sites of Pontogeneia rostrata and Allorchestes angusta were higher during the neap tide than the spring tide, whereas that of Synchelidium lenorostralum was lower during the neap tide. P. rostrata migrated horizontally during the flooding and ebbing tides, but S. lenorostralum and A. angusta did not. Unlike other species, P. rostrata was significantly more abundant at night, suggesting its active nocturnal movement. During flooding tide, P. rostrata was not found on the shore above the mean sea level (MSL) during daytime, but found in 100 cm above MSL at night. Zonal distribution of P. rostrata which was restricted from MSL to 250 cm below MSL, however, did not vary with the day-night cycle during ebbing tide. S. lenorostralum and A. angusta were not found during flooding tide but ebbing tide. The upper distribution limit of the former was 150 cm below MSL, and the distribution of the latter ranged from MSL to 150 cm below MSL. The highest densities of P. rostrata, S. lenorostralum and A. angusta were 32, 26 and 3 ind. $m^{-2}$, respectively. We discussed the relationships between the distribution pattern of three dominant species of gammarid amphipods and their life styles in the sandy shore.

• Applied Microscopy
• /
• v.29 no.2
• /
• pp.241-253
• /
• 1999

Fertilization pattern of north temperate bats is known to be unique for their sperm storage in the female reproductive tract during hibernation (e.g. Korean greater horseshoe bats). They copulate in fall but their ejaculated spermatozoa survive until the next spring. In another words they can persist to survive during long hibernation under the cold condition $(8\sim13^{\circ}C)$ and are to be fertilized with the ovum ovulated in the next spring, so called delayed fertilization. The present study was designed to observe morphological and functional changes of spermatozoa plasma membrane of the bats, hamsters which are hibernators, and mice which are non-hibernators in the room and the cold (bat-hibernation) temperatures and to confirm influence of the temperature on spermatozoa; survival rate, acrosome reaction rate, protein distribution, $Na^+-K^+-ATPase$ activities and scanning electron microscopic histochemistry. Based on the experimental results obtained in the present study, there were no significant morphological and functional differences in the spermatozoa plasma membrane in both the room and cold (bat-hibernation) temperatures and such an absence of difference suggests that the spermatozoa plasma membrane might play a pertinent role as a protector for consistent fertilization during and after hibernation.

• Journal of agriculture & life science
• /
• v.45 no.5
• /
• pp.41-47
• /
• 2011

This study was carried out to provide basic information for assessment conditions as habitat to conserve and restore asiatic black bear released in Jirisan National Park. The field investigation at Piagol, Bitjeom, Jangdanggol, Baemsagol, Chilseon valley, and Hanshin valley which checked for habitat of released asiatic black bear were conducted from 2008 to 2010. There were no obvious differences in home range size of asiatic black bear by study year. The seasonal home ranges were analyzed $25.64km^2$ for males and $17.57km^2$ for female in spring, $73.02km^2$ for males and $27.45km^2$ for females in summer, $41.58km^2$ for males and $13.26km^2$ for females in fall, and $6.11km^2$ for males and $2.89km^2$ for females in winter based on 95% Minimum Convex Polygon (MCP) method, respectively. In average elevation by gender of asiatic black bear, the male was higher than the female. respectively. Average elevation by season were $894{\pm}33m$ in spring, $852{\pm}20m$ in summer, $985{\pm}67m$ in fall, and $996{\pm}26m$ in winter, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.29 no.1
• /
• pp.1-13
• /
• 2024

The southwestern part of the East Sea is known to have a high primary productivity compared to those in the northern and eastern parts, which is attributed to nutrients supplies either by Tsushima Warm Current or by coastal upwelling. However, research on the biological pump in this area is limited. We developed machine learning models to estimate net community production (NCP), a measure of biological pump, with high spatial and time scales of 4 km and 8 days, respectively. The models were fed with the input parameters of sea surface temperature, chlorophyll-a, mixed layer depths, and photosynthetically active radiation and trained with observed NCP derived from high resolution measurements of surface O₂/Ar. The root mean square error between the predicted values by the best performing machine model and the observed NCP was 6 mmol O₂ m^-2 d^-1, corresponding to 15% of the average of observed NCP. The NCP in the central part of the Ulleung Basin was highest in March at 49 mmol O₂ m^-2 d^-1 and lowest in June and July at 18 mmol O₂ m^-2 d^-1. These seasonal variations were similar to the vertical nitrate flux based on the ³He gas exchange rate and to the particulate organic carbon flux estimated by the ²³⁴Th disequilibrium method. To expand this method, which produces NCP estimate for spring and summer, to autumn and winter, it is necessary to devise a way to correct bias in NCP by the entrainment of subsurface waters during the seasons.

• The Korean Journal of Food And Nutrition
• /
• v.13 no.5
• /
• pp.490-505
• /
• 2000

Mugwort (Artemisia sp.) abounds on hedgebank, waysides and grassy places in most part of Europe, Asia and Northern America. This herb has long been associated with witch-craft and magic as a protective charm. Mugwort has been a value as a foodstuff of relieving famine. Proximate composition of mugwort is similar to green vegetables, but it has high level in calcium, potassium and vitamin A content. For medicinal uses, the leaves are harvested twice in spring and autumn before the plant comes into flower and are dried for later uses. Aqueous or organic solvents extracts often have physiologically active constituents. Some extracts of mugwort include cineol, thujone, borneol, camphor, caryophyllene, coumarin, cubebene, pinene, linalool, absinthin etc. The dried leaves have traditionally been used as an antihelmintic, anti-inflammatory, antispasmodic, antitumor, hepatic stimulant, chologogue, emmenagogue, febrifuge, stomachic, tonic etc. Mugwort has been used the dried or green leaves as a flavoring and coloring agents for tea, cake. pastry, bread, noodle, alcoholic liquor, soap and hygienic band.

• The Korean Journal of Zoology
• /
• v.31 no.4
• /
• pp.251-264
• /
• 1988

동면 상태에서 혈액성분의 생화학적 변화치를 조사하고자 전남 각지에 서식 또는 광주직할시 근교에서 양식하고 있는 뱀장어, 개구리, 살모사 그리고 다람쥐를 활동기(7월∼8월), 잠입기(10월∼11월), 동진기(12월∼1월) 및 각려기(3월∼4월)에 채집하였다. 이들 동물들의 혈청에서 Total protein, Albumin, Globulin, A/G ratio, Glucose, Calcium, Urea함유량을 조사하여 얻은 성적을 비교 검토하여 다음과 같은 결론을 얻었다. 1 . Total protein의 변화는 각 동물사이에서 상당한 차이를 보이되 잠입기에 다소 증가하였다. 특히 다람쥐에서 Total protein 함유량이 다른 동물들 보다 많았다. Albumin함유량은 잠입기에 상승하였고 동면기에는 약간의 감소를 보이다가 각성기에는 현저한 감소를 보였다. gloulin함유량은 잠입기에 상당히 상승하고 동면기에 약간의 감소를 나타내었으며 각성기 인 봄철에는 많은 증가 현상을 보였다. 2. 혈청 Urea의 함유량은 동면의 각과정에 따라 상당한 차이가 있었다. 즉 잠입기에 약간 상승하고 동면기에는 저하를 보였으며 각성기에는 전 실험동물에서 검출되지 않았다. 3. 혈당의 변화는 잠입기에 대체로 저하하고 동면기에는 심한 저혈당 수준에 이르렀다. 각성기인 봄철에는 다람쥐를 제외하고는 동면기의 혈희량과 유사하였다. 4. 혈청 Calcium함유량의 변화는 활동기에 비하여 잠입기에는 상당한 증가현상을 보였으나동면기에는 전 실험동물이 거의 같은 수준으로 감소를 보이며 각성기에 까지 감소하였다. In order to the biochemical change of the serological components of hibernating animals, eels(hnguillo joponica Temminck et Schlegel), frogs (Rana nigromacurata Hallowell), snakes (Agkistro-don holds breuicaudus Stejneserl, squirrels (Tamias striatus Linnaeus) which were collected around Gwangiu city and the Chunnam area were observed in accordance with the phases of hibernation. The author described the hibernating cycle as active (June-July), prehibematins(October-Novemberl, hibernating (December-January) and posthibemating phase (March-Aprill. The values of total protein, albumin, globulin, hJG ratlo, calcium, glucose and urea were chiefly investigated in their serum. The results are as following: Total protein was shown to be consider-able in eels, frogs, snakes, squirrels and increased in prehibemation. Especially, the mean value was high in sqirrels. Albumin values was increased during prehibemation. But a little decrease was shown during hibernating and an outstanding decrease during posthibemation. The globulin value increased considerably during prehlbemation but decreased a little during hibernation phase. Changes of urea were shown to be considerable according to the stage of each hibem3-tion. A little increase was shown during prehibemation and decrease during hibernating stage. but urea was not found in posthibemation in any experimental animals. The glucose value was generally decreased during prehibematlon. An extremely little increase in glucose was shown during hibernation (hypoglycemia). All hibernating values except those for squirrels in spring posthibemating phase were at almost the same level. The calcium value was shown to be considerable during prehibemation in comparison with active phase. The same level of decrease was represented in all kinds of animals and continued at the stage of posthibemation.

• Journal of Korean Medical classics
• /
• v.9
• /
• pp.381-429
• /
• 1996

Choo-Joo(鄒澍;1790-1844) was the medicine scholar who lived in the late peroid of the Chung-Dynasty and wrote "Bon-Kyung-So-Jeung(本經疏證)", "Bon-kyung-Sok-So(本經續疏)", "Bon-Kyng-Seo-So-Yo(本經序疏要)". In the books mentioned above, He annotated the chief effectiveness of herbal medicine(本草) which had been presented on "Shin-Nong-Bon-Cho-Kyung(神農本草經)" and "Myoung-Eui-Byul-Lok(名醫別錄)". He defined medical action of 315 herb-items with the many theories of various scholars. Scholars whom Choo-Joo has qoutated belong to the school of study of Chinese classics, and they have regarded "Hwang-Je-Nae-Kyung(黃帝內經)", "Shin-Nong-Bon-Cho-Kyung(神農本草經)" and "Sang-Han-Lon(傷寒論)" as great important cannon and have lived during the Myoung Chung Dynasty. The distinctive character of Choo-Joo belongs to similar academic traditions. It seems that he was appected mainly by "Bon-Cho-Gang-Mok(本草綱目)" written by Lee-Si-Jin(李時珍), Mok-Jung-Soon(繆仲淳)'s "Sin-Nonng-Bon-Cho-Kyung-So(神農本草經疏)", You-Yak-Guem(劉若金)'s "Bon-Cho-Sul(本草述)" and Yang-Si-Tae(楊時泰)'s "Bon-Cho-Sul-Gu-Won(本草述鉤元)". He contributed in two big sides. First, Choo-Joo(鄒澍) have achieved much contribution in biliographical study of Chinese classics(考證學). He analyzed the medical theory of herb-medicine, combining with "Nae-Kyung(內經)", "Sang-Han-Lon(傷寒論)" and many theory of various scholars in order to make research on the chief effectiveness that had been presented in "Shin-Nong-Bon-Cho-Kyung(神農本草經)". Therefore the practical application of medical theory and term which had been represented on classics were offered. Secondary, Choo-joo did great accomplishment in pharmacology. The point of his theory was grasping the effect of a medicine through distinctive one beyond general feature. He set up standards that grasp distintive feature as form, color, energy and taste, place of production and temper. And on the basis of these standards he investigated distinctive feature on various fields, then he induced 'the Uem-Yang-0-Haeng Theory(陰陽五行說)' from distictions. According to the these method of classification, form(形) stand for the resultant shape of herbal function, color(色) represent the active direction of herb, energy and taste(氣味) imply the ultimate active function of herb, the place of production(産地) and the period of occurrence(發生時期) symbolize symptoms. When he applied these method to seek for effetiveness, he regarded the field which revealed most representative feature as of great importance, and Combining remained distinctions with one another, he determined more accurate medicinal value. These method of obsevation solved contradiction which occured by equaly appling all medical herbs for the regular standard. The most important theory that represented in Choo-Joo(鄒澍) is to induce and to certify the distintive feature of herb into the 'Uem-Yang-0-Haeng Theory'. That is, concluded as "spring(生), growing(長), change(化), collecting(收) and storing(藏)". As the results of these studies, he made clear the action of medicine more concretly and made 'the Uem-Yang-0-Haeng Theory(陰陽五行說)' more concret and actual for applying. And he contrbuted to establish the standard for grasping the effect of medicines.

• Korean Journal of Ecology and Environment
• /
• v.41 no.4
• /
• pp.530-540
• /
• 2008

The temporal and spatial variations of size-structured phytoplankton dynamics in Youngsan Lake were investigated to explore potential mechanims controlling the dynamics in the Youngsan Lake. Field data were collected monthly from February to October, 2003 at 6 stations along the axis of Youngsan Lake. In this study, phytoplankton (chlorophyll $\alpha$) were categorized into three size classes: micro-size ($>20{\mu}m$), nano-size ($2{\sim}20{\mu}m$) and pico-size ($<20{\mu}m$). Water temperature, light attenuation coefficients, PAR (photosynthetically active radiation) and suspended solids were measured to analyze relationship between physical-chemical properties and size structure of phytoplankton. Phytoplankton blooms developed during March, July and October in the upper region of the main stem whereas small-scaled spring bloom was observed in the lower region. The scales of phytoplankton blooms were higher in the upper regions than the lower region and blooms were predominated by micro-size class in upper region but predominated by nano-size class in lower region. Growth of size-structured phytoplankton appeared to be controlled by rather light availability than temperature-dependant metabolisms in the system. Phytoplankton growth may be also supported by ambient nutrients available in the water column from analyses of chlorophyll $\alpha$ vs. nutrient concentrations including nitrite+nitrate and orthophosphate. Growth of nano-sized phytoplankton alone appeared to be supported by orthophosphate as well as nitrite+nitrate indicating that response of phytoplankton to nutrient inputs may be size-dependent.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2006.11a
• /
• pp.86-91
• /
• 2006

This study is aimed to provide a guide for PC use space in apartment. To achieve this, a design about PC use space which was considered adequate location, area, form was suggested. As methods of the study, survey research method and case study. The survey was taken by five hundred-eighty-nine people who used PCs in apartment from May 2005 to July 2005 in Je-Ju province for an analysis of data. The results of the survey were showed PC use space situation and furnitures layout patterns. The case was classified by unit plans of size, and it showed design example of PC use space. In case of the 20s pyeong(about 3.30 square meters) type, PC use space was located in dead-space in the residence with minimum scale, because of 20s pyeong types are smaller than the other types. In case of the 30s pyeong type, PC use space which was divided with a partition panel was located in the livingroom expanding the room space to the balcony. In case of the 40s pyeong type, PC use space was located in the room of sons or daughters which was arranged with other furniture. The adequate area of PC use space is 1.4$^{\sim}$2.2 square meters, and it should take into account furniture size and human active sphere. And PC use space of form should consider traffic line, personal space and privacy. Besides it is required of ergonomic design in chair, table in its scale. And it is necessary development of systematic furniture for PC use space.