• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.45-53
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• 2006

The objectives of this study are to determine the primary yield components responsible for yield differences in a subtropical environment of the Hunan province China and in a temperature environment of Honam province Korea. Field experiments were conducted in a subtropical environment in Hunan province China during 2002 and in a temperate environment in Honam province Korea during 2003. Seven rice cultivars were grown under optimum crop management in each experiment field. Yield, yield components and plant dry matter were determined at maturation. The highest yield (567 kg/10a) was produced at Honam province by Jinyou 207, a Chinese cultivar, The maximum yield at Hunan province was 453 kg/10a by Sanyou 63. On the average across cultivars, Honam produced 23% greater yields than Hunan. Sink size (spikelets per $m^2$) was responsible far these yield differences. Panicle number per $m^2$ was much greater at Honam.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.223-229
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• 2017

BACKGROUND: Tillage systems and fertilization play an important role in crop growth and soil improvement. This study was conducted to determine the effects of tillage and fertilization on the microbial biomass C and dehydrogenase activity of soils in a field under cultivation of soybean. METHODS AND RESULTS: An experimental plot, located in the temperate climate zone, was composed of two main sectors that were no-tillage (NT) and conventional tillage (CT), and they were subdivided into four plots, respectively, in accordance with types of fertilizers (non fertilizer, chemical fertilizer, hairy vetch, and liquid pig manure). Microbial biomass C and dehydrogenase activity were evaluated from May to July in 2016. The microbial biomass C and dehydrogenase activity of NT soils were significantly higher than those of CT in all fertilizer treatments, and they were further increased in hairy vetch treatment than the other fertilizer treatments in both NT and CT. The dehydrogenase activity was closely related to microbial biomass C. CONCLUSION: It is concluded that application of green manure combined with no-tillage can provide viable management practices for enhancing microbial properties of soil.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.26-26
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• 2013

The high Antarctic plateau is the driest and coldest environment on the surface of the Earth and offers superlative conditions for the conduct of a wide range of astronomical observations, from optical to millimetre wavebands. This includes, especially, the infrared - where the sky background is greatly reduced from temperate sites - and the sub-millimetre / THz bands - where new or cleaner atmospheric windows can be viewed through. Astronomical observations have now been conducted from five locations on the Antarctic plateau - the South Pole, Domes A, C and F, and Ridge A. Ambitious plans for the construction of observatories there have been announced. An IAU Symposium on "Astrophysics from Antarctica" featured as part of last year's IAU General Assembly in Beijing. This talk will provide an overview of astronomy in Antarctica, describing the special conditions that make some forms of observation particularly favourable there, and discuss the development of observatories on the Antarctic plateau and the plans for their future development.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.352-365
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• 1997

As a serials of researches for the restoration model of evergreen broad-leaved forests, the restoration strategies of the case study areas were proposed. Restoration type of vegetation were classified into an improvement type and a reconstruction type and a reconstruction type for Wando(Island). Improvement type of restoration was suggested for Mokdo(Island). Quercus acuta community, Q. salicina community, Neolitsea sericea community, Castanopsis cuspidata var. sieboldii community, Machilus thunbergii community, Cinnamomum japonicum community, etc. were suggested as a restoration goal of vegetation for Sando(Island). Machlus thunvergii community was suggested as a restoration goal of vegetation for Mokdo(Island). Also the species restoration olan of the Wando(Island) was prepared for Quercus salicina of Fagaceae and Ostrya japonica of Betulaceae those which the natural distribution and population size were very limited. There was no species which needed for species restoration urgently at Mokdo(Island).

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.340-345
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• 2006

A potato (Solanum tuberosum L. cv. Superior) cultivar was grown in aeroponic cultivation system to investigate the effect of root zone cooling in summer. Based on their nutrient uptake, growth responses, and tuberization, the possibilities for potato seed production were determined. Although shoot growth and early tuberization increased in the conventional non-cooling root zone system (root zone temperature of $25\pm2^{\circ}C$), stolen growth, photosynthesis, transpiration rate and number of tubers produced were higher in the cooling root zone system ($20\pm2^{\circ}C$) than in the non-cooling system. Increasing root zone temperature above $25^{\circ}C$ stimulated absorption of K more than T-N, P, Ca, Fe and Mn. On the other hand, root zone temperatures in the range of $20^{\circ}C$ to $25^{\circ}C$ did not affect Mg contents. The lower uptake and supply to leaves of T-N, Fe and Mn at the high root zone temperature promoted early tuberization and advanced haulm senescence. The results stress the importance of keeping root zone temperature to as low as below 20, particularly in summer under temperate Bone.

• Korean Journal of Environment and Ecology
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• v.12 no.3
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• pp.279-289
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• 1998

To monitor vegetation structure of evergreen broad-leaved forest, twenty plots were set up at Wando Arboretum in 1996. Twenty plots were divided into ten experimental plots and control plots. A few evergreen broad-leaved species were planted after selective cutting at ten experimental plots. Dominant species of twenty plots were Quercus acuta, Q. acuta and Carpinus tschonoskii, Pinus densiflora, etc.. Vegetation structure of the experimental plots showed seral stage of succession from P. densiflora community or deciduous broad-leaved forest to Q. acuta community. Dominant species of the experimental plots were changed to Q. acuta or P. densiflora after selective cutting. And a number of species and individuals, coverages etc. were increased at shrub and ground cover layer after treatment.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.464-472
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• 2006

To investigate the forest structure and to suggest a basic management data of the forest in the Kumsaenggol area of Wolchulsan National Park, thirty plots were set up and surveyed. According to the analysis of classification by TWINSPAN, the community was divided into the four groups of Quercus variabilis(I), Q. acutissima(II), Pinus densiflora(III) and P. densiflora-Q. acutissima(IV). From the results of the above, it could be determined that communities I and II were in a developmental stage of the ecological succession, in which the Quercus app. community progressed from Pinus densiflora. Additionally, communities III and IV are also in a developmental stage and will be expected to show competition regarding Pinus densiflora.

• Korean Journal of Environment and Ecology
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• v.11 no.4
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• pp.450-461
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• 1998

To investigate the plant community structure of Paekdam-Valley in Soraksan National Park, fifty-two plots have been set up and surveyed. By DCA ordination technique, the plant communities were classified into fkve community types, which were Pinus densiflora community and Q. mongolica community. It was supposed that Q. serrata community change to C. laxiflora community. It seemed that P. densiflora community, deciduous broad-leaved mixed forest and Q. serrata community would not be replace by another woody species. And it seemed that C. laxiflora community succeeded to Q. serrata community, so it was similar to the typical ecological succession of natural forest in the middle temperate regions. The range of Shannon's diversity index was 0.9827~1.2946(Unit area : 400m$^2$) and that was over another Korean National Parks area relatively.

• ALGAE
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• v.34 no.3
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• pp.229-236
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• 2019

Despite the abundance of seaweeds from Ulleungdo Island, genetic diversity and distribution of edible brown algae from the island remain unstudied. We analyzed mitochondrial cox3 sequences from 86 specimens collected in the island and from the nearby Korean Peninsula. Our cox3 phylogeny for the first time confirmed the occurrence of fives species from Ulleungdo Island; Petalonia binghamiae, P. fascia, Planosiphon zosterifolius, and two cryptic species previously identified as Scytosiphon lomentaria. P. binghamiae was relatively homogeneous with three haplotypes. P. fascia comprised four haplotypes, which were grouped into two genetic lineages. S. lomentaria was heterogeneous with nine haplotypes and was divided into two cryptic species; one species clustered with taxa from cold waters while the other clustered with taxa from temperate and cold waters. Low genetic diversity in P. binghamiae while high genetic diversity in S. lomentaria from Ulleungdo Island are comparable to patterns observed from other species from the Korean peninsula. Ulleungdo Island, although small in size, is an ideal field laboratory to investigate genetic diversity and distributions of economic marine algae.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.334-351
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• 1997

To study restoration model of evergreen broad-leaved forests in warm temperate region, vegetation structure was studied at Wando(Island) as a case study. Quercus acuta was a dominant species at evergreen broad-leaved forests in Wando(Island). Majority of evergreen broad-leaved forests was a thirty years old coppice forest. Reforested vegetation and deciduous broad-leaved forests was developed at a mid-slope districts and a piedmont. Deciduous broad-leaved forestsconsisted of Quercus serrata, Carpinus tschonoskii, Carpinus coreana, etc., was developed at a ridge and higher districts. Evergreen broad-leaved woody plants were growing at a forest floor of deciduous broad-leaved forests. The species over sixty percent of constanty ratio in forty seven plots were Ligustrum japonicum, Trachelospermum asiaticum var. intermedium, Quercus acuta and Eury japonica. The vascular plants in the Wando(Island) was summarized as 488 taxa which composed as 101 families, 321 genus, 426 species, 56 varieties, 5 forms and 1 hyvrid. Evergreen broad-leaved woody stecies was 32 taxa which composed as 23 genus, 30 species and 2 varieties. The species such as Liliope platyphylla of Liliaceae and Pueraria thunbergii of Leguminosae, etc. was recorded as the highest values for their widely distribution in the areas. On the contrary, and forty taxa of plants such as Viburnum erosum of Caprifoliaceae, Traceholospermum asiaticum var. intermedium was recorded as over 50% of constancy ratio. Two hundred and nine taxa of plants such as Juglans manshurica of Juglandaceae, Cornus walteri of Cornaceae and Rodotypos scandens of Rosaceae, etc. was showed the specific trends due to long-term artificial disturbance. The forest of Pinus thunbergii showde the highest species diversities(155 species per 600m$^{2}$), while the Cinnamomum japonicum-Tracheolospermum asiaticum var. intermedium community showed the lowest species diversities(23 species per 600m$^{2}$).