• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.5-11
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• 2008

This study examined the characteristics of Pinus thunbergii community that forms a windbreak forest around the coast of Gwanmaedo located in Jodo-myeon, Jindo-gun, Jeollanamdo which is located in the south-western areas of Korea from December 2005 to April 2007 and to suggeste the ecological management methods of coastal windbreak areas. P. thunbergii community, a coastal windbreak forest of Gwanmaedo, was classified into disturbance, growth, mixture, stability, and back mountain vegetation according to major companions species and vegetation types. P. thunbergii community of disturbance and growth vegetation needs active management through tree thinning, mowing, weeding out, use of rest space, and felling sick pine trees. P. thunbergii community of mixture, stability, and back mountain vegetation needs active preservation of a coastal windbreak to restore natural vegetation by making a windbreak walk and a forest buffer zone and inducing vegetation succession. Accordingly, in this study, ecological management methods were suggested according to the actual state of distribution by habitat characteristics of coastal windbreak areas such as management of beaches and surrounding area of idle lands, restoration of back wetlands, inhibition of foreign plants, maintenance of diversity of species and habitats, and prevention of aging and spread of damage from insects.

• Journal of Korean Elementary Science Education
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• v.26 no.1
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• pp.41-48
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• 2007

The purpose of this study is to examine how many plant names elementary school children how, and what kind of criteria they use for classifying these plants. The sample involved 926 students from the 2nd, the 4th, and the 6th grades dwelling in one urban, three suburban, and six rural areas. Their level of perception on the name of plants increased in correlation to the elevation of the grade level. However, different patterns of increases were shown depending on the local environments in which they live. The most well-known plant names for students were the rose of Sharon, the rose and the pine tree. The students mostly classified the plants using the following criteria such as 'with or without flower' and 'edible or inedible' regardless as to whether they had prior loaming experience of plant classification. 65.3% of the 6th graders correctly grouped 5 kinds of plants into the flowering and the non-flowering plant categories at the 1st level of classification. However, only 17.9% and 7.7% correctly divided the flowering and the non-flowering plants into two subgroups at the 2nd level of classification respectively. Therefore, their abilities in plant classification was shown overall to be poor. The students living in suburban areas appeared to be harmonized with both the natural and urbanized surroundings and classified the plants more scientifically than those from the urban or rural areas were able to. This suggests that the conception of plant classification by children is affected by the environment in which they live. If children have more opportunities to observe plants in surroundings such as their classrooms and school gardens, it will help them to form the relevant scientific concepts as well as to correct any alternative conceptions related to classification.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.33-36
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• 1985

This experiment was carried out to investigate the effect of crown density of trees on the growth and yield of cool-season grasses in forest. The species used in this study was orchard-grass (Dactylis glomerata L.) and 4 levels of tree crown density(O=full sunlight, 25, 50 and 75%) were treated. The experiment was performed at the experimental filed of the Livestock Experiment Station in Suweon, during 1979 to 1950. The results obtained are summarized as follows: 1. Maximum leaf area was obtained at 25% crown density of trees, followed by 0, 50 and 75%, regardless of cutting times. 2. Plant height tended to increase as the crown density of trees increased. However, there was no difference between 0% and 25% crown density of trees. 3. There was a negative correlation between plant height and leaf area of orchardgrass grown under pine trees. 4. The more dry matter yield of orchardgrass was obtained at 25% crown density of trees (p<0.05), follwed by 0, 50 and 75%, respectively. However, there was no significant difference between 0% and 50% crown density of trees. Therefore it is suggested that the critical level of crown density of trees is 50% to culture of cool-season grasses in forest.

• Journal of Environmental Impact Assessment
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• v.15 no.5
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• pp.323-337
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• 2006

This work discussed the species composition, phylogeny, spatio-temporal distribution, ecology and natural history of North Korean Pinaceae or pine tree family, which seems to be important to maintain nature and ecosystem in the Korean Peninsula. Out of five genera and sixteen species of Pinaceae of the Korean Peninsula, North Korea contains four genera and eleven species of Pinaceae, including Pinus densilflora, P. koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis, Abies holophylla and A. nephrolepis. In terms of phylogeny Pinus is closely related to Picea, and followed by Larix. Abies is close to Tsuga which only occur at Ullung Island. Distributional pattern of North Korean Pinaceae can be classified into four types; three species of nation-wide montane type i.e., Pinus densilflora, P. koraiensis and Abies holophylla, four species of central and northern subalpine type, i.e., Pinus pumila, Picea koraiensis, Larix gmelini and Abies nephrolepis, one nation-wide subalpine type, Picea jezoensis, and three species disjunctive to north type, i.e., Picea koraiensis var. koraiensis, P. pungsanensis, and Larix gmelinii var. olgensis. Pinaceae species occurring on the alpine and subalpine belts of North Korea, such as Pinus koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis and A. nephrolepis are considered as the glacial descendant from the boreal region. Those species might have migrated from the north during the Pleistocene glacial epochs in search of favourable condition, and since the Holocene period they survived on the hostile alpine and subalpine environments, in which they are more competitive than warmth-tolerant temperate vegetation. Certain species, such as Picea pungsanensis, is segregated on the isolated mountains since the Pleistocene period, and forced to adapt to local environment, and eventually became an endemic species of North Korea. Recent rapid global warming trend especially in northern high mountains of North Korea could cause an unfavourable environment for the survival of cold-tolerant Pinaceae of the alpine and subalpine belts. Pinus densiflora, which is occurring on the montane belt might faced with difficulties due to both the deforestation and the outbreak of insect-borne disease, such as Bursaphelenchus xylophilus.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.143-149
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• 2000

From the soils of soybean fields in Cotton Branch Station (CBS) and Pine Tree Station (PTS), Arkansas, USA, various single spore isloates of sudden death syndrome (SDS) pathogen were obtained on modified Nash ＆ Snyder's medium (MNSM) with dilution plating technique and transferred to potato dextrose agar (PDA) medium to identify the cultural colony shape. The colony shapes of these isolates resembled F. solani isolate 171 which was white and chalky shaped on MNSM and most of them had unique form of morphology which produced white margin and blue center colony on PDA. Although, some of these isolates had more dark blue or showed slightly different color, all isolates that were selected randomly for green-house inoculation assay produced typical foliar symptoms on leaves of soybean, Hartz 6686. To determine the genetic differences among the isolates, mitochondrial DNA restriction fragment length polymorphism (RFLP) was conducted with fourty isolates from both fields, using mtDNA probes, 2U18 and 4U40, derived from Colletotrichum orbiculare. We obtained distinctive RFLPs in each treatment of restriction enzyme, EcoRI and HaeⅢ. Isolates, 11-2-5 and 14-3-1-1, from CBS and isolates, 104-3-1-2 and 701-1-5-1, from PTS showed different band patterns from 171 in both or in either treatment of restriction enzymes. Even if some of these isolates showed heterogeneous, they were more closer to 171 than PN603. And, also, rest of the thirty-six isolates had exactly same polymorphisms as 171 in each treatment of restriction enzyme. Although, some of the isolates showed the different morphological shape on PDA and slightly different band patterns on RFLPs, all of the isolates selected on MNSM due to their distinctive colony shape from other fungi produced the typical foliar symptoms on soybean leaves in greenhouse inoculation assay. It might be suggested that these isolates were not genetically different from check isolate 171 and they were unique strain of F. solani.

• Korean Journal of Pharmacognosy
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• v.18 no.3
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• pp.196-201
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• 1987

A study was carried out to investigate the possibility of acclimation of Coptis japonica Makino in Korea. Coptis japonica could be grown within 4 years as a medicinal crude drug if it is cultivated in the area of mountain facing north(300m above sea level) with 70% light interception and appropriate soil texture. It is to be noted that the propagation of the plant is more important than the yield of berberine because the berberine contents do not change in different conditions. The results were as follows; 1. The germination rates of the seeds by covering with the pine tree leaves were the highest and averaged 63%. 2. The germination rates of dry seeds were not affected in spite of low temperature and $GA_3$ treatment. 3. The germination rates of the seeds stored in moistured sand were averaged 85%, but in dry state, they were not germinated. 4. The number of leaves and fresh weight of Coptis japonica from the area of mountain facing north were increased significantly. 5. The growth and fresh weight of Coptis japonica were reduced in clay. 6. The best growth was obtained under 70% light interception. It is possible to intercrop between evergreen trees. 7. The foliage dressing did not affect the growth. 8. The number of leaves and fresh weight were increased from the 3rd year, and the average weight of rhizomes was 5.7g in 4th year. 9. The berberine contents of the rhizomes of Coptis japonica under various treatment conditions ranged from 9 to 10%. Coptidis Rhizoma from this study and from Korean market showed much higher berberine contents than those from Japanese market.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.243-249
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• 1995

In order to investigate the origin of sulfate in rain waters and to evaluate the feasibility of using sulfur isotope method as a tracer of atmospheric pollutants, the sulfur isotopic ratio of sulfate in rain waters collected in Chonju city from October 1994 to March 1995 was monitored and was compared with those of possible sources proposed by previous works. The pH of rain waters shows an intermediate acidic range from 4.45 to 6.88 and their daily variation appears to be well correlated with to the amount of precipitation. The sulfur isotopic ratios of sulfate in rain waters show a highly restricted range from 0.0 to + 1.8‰. The ${\delta}^{34}S$ values are similar to those of soil and pine tree surrounding Chonju city, but largely deviate from those of China. D-parameter($d={\delta}D-8{\delta}^{18}O$) of rain waters varies from 9.4 to 28.8. The values indicate that the rain waters in Chonju city are originated from the rainy front of China continent. All data obtained from this study suggested that sulfate in the rain waters collected in Chonju city was mainly derived from the sulfur dioxide gas emitted by the petroleum combustion. Therefore, sulfur isotopic study for the precipitation provided an excellent tool for environmental assessment in this region and for tracing the source of atmospheric pollutants.

• Journal of Conservation Science
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• v.26 no.1
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• pp.77-83
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• 2010

The damage from the underground termite cannot be discovered with peculiar appearance of building but hollow phenomenon will occur. But there is no case in Korea as a non-destructive measurement of termite activation. Therefore, this research constructs non-destructive diagnostic techniques for wooden cultural properties using microwave detector (Termatrac, Australia). Result of maximun distance were measured 16cm (Pine tree, sensitivity 5, 6), 17cm (Zelkova and Douglas fir, sensitivity 5, 6). These results are expected that can be applied in the field. Result of field test using microwave detector, 33.8% of the wooden cultural properties were damaged by termites, and until now 7.8% (18 buildings) are being damaged in nationwide (total 231 buildings). Based on the above results, microwave detector will be able to be utilized effectively for detecting termite, preventing intrusion in wooden structure, and making full use of monitoring system periodically. In addition, it could be of great worth in preventing insect and microorganism in wooden structure.

• Clinical and Experimental Pediatrics
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• v.55 no.9
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• pp.322-329
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• 2012

Purpose: Aeroallergens are important causative factors of allergic diseases. Previous studies on aeroallergen sensitization rates investigated patients groups that had visited pediatric allergy clinics. In contrast, we investigated sensitization rates in a general population group of elementary school to teenage students in Incheon, Jeju, and Ulsan. Methods: After obtaining parental consent, skin-prick tests were performed on 5,094 students between March and June 2010. Elementary school students were tested for 18 common aeroallergens, whereas middle and high school students were tested for 25 allergens. The 25 allergens included Dermatophagoides pteronyssinus, Dermatophagoides farinae, pollen (birch, alder, oak, Japanese cedar, pine, willow, elm, maple, Bermuda grass, timothy grass, rye grass, orchard grass, meadow grass, vernal grass, mugwort, Japanese hop, fat hen, ragweed, and plantain), and mold (Penicillatum, Aspergillus, Cladosporium, and Alternaria). Results: The sensitization rates in descending order were 25.79% (D. pteronyssinus ), 18.66% (D. farinae ), 6.20% (mugwort), and 4.07% (willow) in Incheon; 33.35% (D. pteronyssinus ), 24.78% (D. farinae), 15.36% (Japanese cedar), and 7.33% (Alternaria) in Jeju; and 32.79% (D. pteronyssinus), 30.27% (D. farinae), 10.13% (alder), and 8.68% (birch) in Ulsan. The dust mite allergen showed the highest sensitization rate among the 3 regions. The sensitization rate of tree pollen was the highest in Ulsan, whereas that of Alternaria was the highest in Jeju. The ragweed sensitization rates were 0.99% in Incheon, 1.07% in Jeju, and 0.81% in Ulsan. Conclusion: The differences in sensitization rates were because of different regional environmental conditions and distinct surrounding biological species. Hence, subsequent nationwide studies are required.

• Journal of the Korean Professional Engineers Association
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• v.17 no.3
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• pp.6-21
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• 1984

A rock slide in amount of 100 tons in weight happened at 7: 10 a.m., 4th October 1982, on the southwestern ridge of Mt. Seunghag, Busan City. The original rock mass of the rock slide is located 850m west from the Dangri Crushed Stone Quarry. The geology of the area consists of agglomerate, andesite, andesitic tuff, and shale hornfels of the Cretaceous Yucheon Group. The rock blocks were first shifted along the steep joint plane on an andesite outcrop at the site and then to the eastern foot of the mountain slope where some private houses are placed. The mountain slope is covered with thick superficial soil. A slided monolithic-block with 83 tons in weight from the rock slide met with an accident of striking against a house with a tremendous force, to which much damage was done as much as its half was destroyed. The rock-slided block pierced the board-floored room only posited at the center and by the bedroom of the house making a pass like a bullet hole, and hence cut a big pine tree with 24 centimeters in diameter at a distance of 26 meters down the house. However nobody was killed or injured in the stricken house, though seven family members were stayed therein at the very time of accident. They really met a rare opportunity in an unhappy disaster. Measurements of the rock slide were made in the course of the field survey. The monolithic mass was transported by way of saltation, rolling, and sliding to a distance of 300 meters down along the slope dipping 30$^{\circ}$ east. It took about 16 seconds front tile outcrop to the terminal. The acceleration value of the monolithic rock slide is 2.35m/sec$^2$.