• The Korean Journal of Quaternary Research
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• v.22 no.2
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• pp.6-11
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• 2008

Vegetation change reconstructed by pollen analysis is effective to clarify natural conditions such as climate and soil as well as intensity of human activity. Pollen analysis in Korea is difficult to obtain peaty soil sedimented by low relief geomorphollogically and formation age is usually confined to obtain information during young Holocene as well as little absolute age data. Isopollen map was constructed in order to analyze the change of vegetation environment time-spatially during Holocene based on the 30 data with age dated from 78 results from pollen analysis in Korea. The indicatives for vegetation environment were the main trees in Korea such as Alnus, Pinus, Quercus and AP/NAP during the periods of 6,000 y.BP, 4,000 y.BP, 3,000 y.BP, 2,000 y.BP, 1,000 y.BP. As a result, the regional time-spatial patterns of vegetation distribution appeared clearly on the isopollen map. The dominant vegetation stage was repeated in the different pattern e.g. the dominance between Alnus and Quercus at West Coast and between Pinus and Quercus at East Coast competitively.

• KCID journal
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• v.18 no.2
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• pp.76-86
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• 2011

This study was conducted to clarify community characteristics of waterbirds migrating to Seamangum area from 2002 to 2009. Total maximum count of waterbirds observed at Saemangum area was 686,337 individuals of 176 species. 158 species and 548,989 individuals were recorded on Mangyung Estuary and 158 species and 213,794 individuals were recorded on Dongjin Estuary. Dominance species were Baikal Teals Anas formosa (40.80%), Great Knots Calidris tenuirostris (18.03%), Mallards Anas platyrhynchos (11.67%) and Dunlins Calidris alpina(6.02%). Shorerbirds were declined and waterfowl were increased during survey periods. Natural monuments and endangered birds were 27 species.

• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.109-118
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• 2015

Allelopathy is an ecological phenomenon that refers to the beneficial or harmful effects of one plant on another plant, both crop and weed species, by the release of organic chemicals (allelochemicals) from plant parts by leaching, root exudation, volatilization, residue decomposition in soil and other processes in both natural and agricultural systems. Allelopathy can affect many aspects of plant ecology including occurrence, growth, plant succession, the structure of plant communities, survival, dominance, diversity, and plant productivity. In this review, we describe the concept of allelopathy, some mechanisms of operation within plants and then focus on a select number of gymnospermous tree genera: Ephedra, Pinus, Taxus, Cedrus, Juniperus, Picea, Cunninghamia and Araucaria. Pinus, Taxus (yew) and Cedrus (cedar) trees have a strong negative allelopathic effect on the germination, growth, or development of other plant species in the forest community.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.23-23
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• 2004

Four times of field survey were carried out to collect fish samples at six stations in Shinpo district, North Korea in October 1997, July 1998, May and October 2002. Sampling stations were located in upstream, middle and down of the southern river of Bukchong and three brackish lakes of lake Hommanpo, Daein and Hyunkum, respectively. A total of 29 species belonging to 11 families occurred. Family Cyprinidae showed the prosperity in species number of 28% among total species occurred. No natural monument fishes or rare species were captured. Ten commercial fishes, five anadromous ones and five brackish ones were identified. Feeding habits divided fish fauna with 11 carnivores, two herbivores and seven omnivorous ones. In the river, 20 species belonging to seven families inhabited, 18 species of 6 families in lake Homanpo, 21 of seven III Hyunkum and 23 of eight in Daein, respectively. Ecological indices of richness, diversity and evenness were highest in lake Daein and dominance index was highest in lake Hyunkum.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.04a
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• pp.176-177
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• 2007

We determined how presence of heterospecific individuals in the vicinity of a focal individual affects the behavior of two critically endangered species of cranes on their wintering grounds at Cheolwon in the Korean Demilitarized Zone(DMZ). The Red-crowned crane, Grus japonensis, is larger than the White-naped crane, Grus vipio, and it dominates the White-naped crane in aggressive interactions. We showed that the dominant species increases foraging activity in the presence of the subordinate species presumably because of scrounging of the food from the subordinate. Because interspecific interactions may affect avian endangerments this behavioral findings should be taken into account when managing winter refuges for the two engendered crane species.

• Journal of Information Processing Systems
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• v.17 no.1
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• pp.1-13
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• 2021

In this research, we study the problem of font image skeletonization using an end-to-end deep adversarial network, in contrast with the state-of-the-art methods that use mathematical algorithms. Several studies have been concerned with skeletonization, but a few have utilized deep learning. Further, no study has considered generative models based on deep neural networks for font character skeletonization, which are more delicate than natural objects. In this work, we take a step closer to producing realistic synthesized skeletons of font characters. We consider using an end-to-end deep adversarial network, SkelGAN, for font-image skeletonization, in contrast with the state-of-the-art methods that use mathematical algorithms. The proposed skeleton generator is proved superior to all well-known mathematical skeletonization methods in terms of character structure, including delicate strokes, serifs, and even special styles. Experimental results also demonstrate the dominance of our method against the state-of-the-art supervised image-to-image translation method in font character skeletonization task.

• Journal of Korean Society of Forest Science
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• v.51 no.1
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• pp.1-21
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• 1981

Populus glandulosa and Populus tomentiglandulosa, which were known to be natural hybrids, were examined for morphological, physiological and karyological traits to illucidate its hybridity and taxonomical importance. The results abtained were as follows; 1. Survival rate in rooting of cuttings and grafting was different between the hybrids and their rooting abilities showed incomplete dominance. 2. Their leaf openings showed incomplete dominance. The leaf longevities of P. alba ${\times}$ glandulosa and P. tomentiglandulosa were stronger than the other hybrids. 3. There were differences in resistance to toxicity of $KClO_3$ between the hybrids. 4. Many external leaf characters of the hybrids also showed incomplete dominance. P. tomentiglandulosa was similar in those characters to P. alba ${\times}$ glandulosa while P. glandulosa was similar to hybrids crossed, reciprocally crossed or back-crossed between P. davidiana and P. alba. 5. Their numbers of male flower showed incomplete dominance or hybrid vigor. The numbers of P. tomentiglandulosa were similar to thosa of P. alba ${\times}$ glandulosa while those of P. glandulosa to those of P. alba ${\times}$ davidiana or P. davidiana ${\times}$ alba. 6. Morphology and band color of male catkin bract showed incomplete dominance. Those of P. glandulosa were similar to those of P. alba ${\times}$ davidiana while those of P. tomentiglandulosa to those of. P. alba ${\times}$ glandulosa. 7. There were differences in vascular bundle number and arrangement of petiole between the hybrids. 8. Differences in the anatomical traits of stem did not exist between the hybrids but those in wood fiber size existed. 9. The chromosomes of artificial hybrids, P. glandulosa and P. tomentiglandulosa showed irregular behavior in metaphase I and II. 10. All hybrids including P. glandulosa and P. tomentiglandulosa showed small number of P.M.C. with 19 II but many univalent chromosomes were exhibited in metaphase I. 11. All hybrids including P. glandulosa and P. tomentiglandulosa showed a little abnormal nuclear plates as laggard chromosome and chromosome bridge in anaphase I and II. 12. The frequency of pollen tetrad and fertile pollen was low in most of the hybrids including P. glandulosa and P. tomentiglandulosa.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.556-565
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• 2010

Community analysis based on functional feeding groups of benthic macro invertebrates at Wangpi-cheon was assessed with the result of four field survey from October, 2007 to May, 2008. A total 138 species of benthic macro invertebrates in 58 families, 16 orders, 6 classes, and 4 phyla were collected during the field surveys. The result of EPT index value showed high value of 61.59% and it means that the stream ecosystem of Wangpi-cheon is very clear and healthy. In this study the functional feeding groups in Wangpi-cheon were divided into two groups. First, Scrapers and Collectors-Gathering group which is normally dominant in midstream showed higher dominance in main stream than tributary. Second, shredders group showed higher dominance in tributary than main stream like as the general characteristics of upriver. With the result of cluster analysis based on the similarity index, the study areas could be grouped into a natural area(A group) and an artificial disturbance area(B group; site 8 and 11) where embankment, bank and levee had been built near by. And also, the natural area(A group) was classified into two groups which had the characteristic of main(site 1, 2, 3, 4 and 7) stream and tributary(site 5, 6, 9 and 10) respectively.

• Korean Journal of Plant Resources
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• v.25 no.6
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• pp.719-730
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• 2012

This study was conducted to investigate the environmental characteristics of natural habitats, and the genetic variations in samples from 19 different quadrates of Asplenium scolopendrium 10 habitats. The natural habitats of A. scolopendrium were located at an altitudes 110-973 m with inclinations of $7-30^{\circ}$. All the quadrates were located on north facing slopes. The average field capacity of the soil is 31.4%, with organic matter at 16.7%, and the pH is 5.84. The soil texture was confirmed as sandy loam in 8 habitats and silt loam in 2 habitats. A total of 214 vascular plants were identified from 10 habitats. The importance value of the herbaceous layer (H) was the highest in A. scolopendrium, at 10.4%, followed by Arachniodes standishii (7.3%), Dryopteris crassirhizoma (6.5%), and Polystichum tripteron (5.3%), which implies that the natural habitats of A. scolopendrium are affinity with ferns. The species diversity of A. scolopendrium was estimated as on average 1.09, while the dominance and evenness were 0.12 and 0.87, respectively. The result of the RAPD analysis, among 59 bands amplified with a primer, 25 (42.4%) showed polymorphism. Twenty-one individuals of 10 habitats could be classified into four groups with similarity coefficient values ranging from 0.74 to 1.0. Mt. Mullae and Geumdaebong populations shows basal branching within the 21 individuals. Ulleung-do island and Jeju-do island population forms an independent clade, respectively. Mt. Moak and Byeonsan-bando clade formed a sister to the Ulleung-do island and Jeju-do island clade.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1319-1328
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• 2011

Rhododendron brachycarpum is a evergreen broad-leaved shrub and belongs to the Ericaceae family and the Rhododendron genus. It is well known for its beautiful leaves and flowers. There are 11 species of the Rhododendron genus in Korea. It includes 3 species - Rhododendron brachycarpum, Rhododendron aureum Georgi and Rhododendron brachycarpum var. roseum Koidz. They grow naturally over 1,000 meters above sea level of the Baekdu Mountain Range in Korea. These habitats, according to investigations of 9 Rhododendron brachycarpum natural habitats, are mostly located on the slope of mountains facing north at an altitude of 1,200 m to 1,526 m above sea level with angle of inclination from 30 degrees to 45 degrees. Based on the result of vegetation analysis of dominance species in the quadrates, there are Quercus aliena, Quercus mongolica Fisch. ex Ledeb, Abies holophylla in species of upper trees, and so on. Dominant species of woody plants in tree layer are Quercus aliena, Quercus mongolica Fisch. ex Ledeb, Abies holophylla, Betula platyphylla and Veeatrum patulum Loes. fil, Erythronium japonicum, Dryopteris crassirhizoma, Paeonia japonica var. glabra Makino are founded in herbaceous plants. And we can see another result of the investigation that the flowering rates of the plants with the buds are highly ranked mountains such as Mt. Hambaek 68%, Mt. Gyebang 40%, Mt. Yagksu 9%, Mt. Gaein 7% and Mt. Seolag 0%. The results show that there are 24 over 15-year-old Rhododendron brachycarpums in Mt. Odae and are 56 under 15-year-old trees in Mt. Hambaek and are no trees in Mt. Gyebang and are 9 over 30-year-dead trees only in Mt. Taebaeg. Out of found trees, the highest tree is 7 m in height and 0.6 m in diameter. Also this result shows what are the vulnerability factors of the natural habitats. They are as follows: indiscriminate trails in mountains, damages by mountain climbers, uncareful plant collecting, the fierce competitions with other plants such as Acer pseudosieboldianum var. ishidoyanum Uyeki, Quercus aliena, Celastrus orbiculatus and damages by disease and insect, unusual temperature in natural habitats, etc. Rhododendron brachycarpums have high ornamental value and excellent pharmaceutical effect. But the areas of its habitats decrease dramatically. So we need measures to protect and their natural habitats. It is necessary that we conductfurther investigations to designate conservation area for Rhododendron brachycarpums.