• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.235-244
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• 1991

An epidemiological study and mass treatments of Enterobius vermicularis infection among children near Wonju area of Kangwon province were carried out. The children were divided into 4 groups according to their residing localities; children in the mountainous area, rural area, urban area and in orphanage. They were examined by adhesive cellotape anal swab technique, and egg positive rates were obtained. The rates of egg reduction and re-infection rates after repeated mass treatments were also observed. The results obtained were as follows: 1. The overall egg Positive rate of E. vermicularis in the first screening was 19.9% (251 out of 1, 262 examinees; 19.7% in males and 20.1% in females). The positive rates were 13.0% in the mountainous area, 11 9% in the rural area, 15.1% in the urban (medium-sized) area and 61.9% in orphanages. 2. The highest positive rates were observed in the kindergarten children, and 1st and 2nd grade children of primary schools (26.2~32.2%), and the lowest rate (13.6%) in 6-year grade children of primary schools. 3. Cumulative detection rates from 3 repeated anal swabs at 4~5 days interval were higher (70.8%) than those from single anal swabs (50.0~59.2%). 4. Out of the examinees who showed the highest cumulative positive rate (70.8%), about 39.2% were consecutively positive in 3 anal swabs. Among different groups of children, the higher the total egg detection rates (87.5%), the higher the consecutive positive rates (71.9%) . 5. A total of 2, 609 (male : female=1 : 12.4) worms were collected from 17 egg-positive cases treated with anthelinintics. The mean number of worms per child was 153 (range: 4-824) . 6. The egg-positive cases in several studied groups (180 children) were treated with anthelmintics 6 times at 3-week intervals. In this case, the overall positive rate was decreased from 54.8% to 2.2% at 15 weeks after the treatments, but no complete negative conversion was experienced. However, in a group of children (154 children) including egg Positive and negative cases who were both treated with anthelmintics at 3-week interval, a complete egg-negative conversion was observed in the 9th week after treatments. 7. The egg-detection rate in the brothers or sisters of egg Positive children was 70.0% (28 out of 40 examined), and the egg-positive rate according to the family unit was 69.7%. In summarizing the above results, it is concluded that Enterobius vermicularis infection is still highly prevalent among children in Korea, and that repeated mass treatments of more than 3 times will be effective for control of this infection.

• Korean Journal of Heritage: History & Science
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• v.49 no.2
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• pp.172-189
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• 2016

In this research, literature research on the Odong material, mixture ratio, casting method and casting facility was conducted on contemporary documents, such as Cheongong Geamul. Also, a long sword was produced using the Odong inlay technique. The sword reproduction steps were as follows; Odong alloying, silver soldering alloying, Odong plate and Silver plate production, hilt and sheath production, metal frame and decorative elements, such as a Dugup (metal frame), production, Odong inlay assembly and final assembly. For the Odong alloy production, the mixture ratio of the true Odong, which has copper and gold ratio of 20:1, was used. This is traditional ratio for high quality product according to $17^{th}$ century metallurgy instruction manual. The silver soldering alloy was produced with silver and brass(Cu 7 : Zn 3) ratio of 5:1 for inlay purpose and 5:2 ratio for simple welding purpose. The true Odong alloy laminated with silver plate was used to produce hilt and sheath. The alloy went through annealing and forging steps to make it into 0.6 mm thick plate and its backing layer, which is a silver plate, had the matching thickness. After the two plates were adhered, the laminated plate went through annealing, forging, engraving, silver inlaying, shaping, silver welding, finishing and polishing steps. During the Odong colouring process, its red surface turns black by induced corrosion and different hues can be achieved depending on its quality. To accomplish the silver inlay Odong techniques, a Hanji saturated with thirty day old urine is wrapped around a hilt and sheath material, then it is left at warm room temperature for two to three hours. The Odong's surface will turn black when silver inlay remains unchanged. Various scientific analysis were conducted to study composition of recreated Odong panel, silver soldering, silver plate and the colouring agent on Odong's surface. The recreated Odong had average out at Cu 95.57 wt% Au 4.16wt% and Cu 98.04 wt% Au 1.95wt%, when documented ratio in the old record is Cu 95wt% and Au 5wt%. The recreated Odong was prone to surface breakage during manufacturing process unlike material made with composition ratio written in the old record. On the silver plate of the silver and Odong laminate, 100wt% Ag was detected and between the two layers Cu, Ag and Au were detected. This proves that the adhesion between the two layers was successfully achieved. The silver soldering had varied composition of Ag depending on the location. This shows uneven composition of the silver welding. A large quantities of S, that was not initially present, was detected on the surface of the black Odong. This indicates that presence of S has influence on Odong colour. Additional study on the chromaticity, additional chemical compounds and its restoration are needed for the further understanding of the origin of Odong colour. The result of Odong alloy testing and recreation, Odong silver inlay long sword production, scientific analysis of the Odong black colouring agent will form an important foundation of knowledge for conservation of Odong artifact.

• Journal of Distribution Science
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• v.8 no.3
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• pp.17-26
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• 2010

Recently concerns have been raised due to the unbalanced supply of crops: the price of crops has been unstable and at one point the price went up so high that the word Agflation(agriculture+ inflation) was coined. Korea, in particular, is a small-sized country and needs to secure the stable supply of crops by investing in the produce importation at a national level. Investment in foreign produce importation is becoming more important as a measure for sufficient supply of crops, limited supply of domestic crops, weakened farming conditions worldwide, as well as recent changes in the use of crops due to the development of bio-fuels, influence of carbon emission on crops, the price increase in crops, and influx of foreign hot money. However, there are many problems with investing in foreign produce importation: lack of support from the government; lack of farming information and technology; difficulty in securing the capital; no immediate pay-off from the investment and insufficient management. Although foreign produce is originally more price-competitive than domestic produce, it loses its competiveness in the process of importation (due to high tariffs) and poor distribution system, which makes it difficult to sell in Korea. Therefore, investment in foreign produce importation is being questioned for feasibility; to make it possible, foreign produce must maintain the price-competitiveness. Especially, harvest of agricultural products depends on natural and geographical conditions of each country and those products have indigenous properties, so distribution system according to import and export of agricultural products should be treated more carefully than that of other industries. Distribution costs are differentiated into each item and include cost of sorting and wrapping, cost of wrapping materials, cost of domestic transport, cost of international transport and cost of clearing customs for import and export. So transporting and storing agricultural products generates considerable costs compared with other products. Also, due to upgrade of dietary life, needs for stability, taste and visible quality toward food including agricultural products are being raised and wrong way of storage causes decomposition of food and loss of freshness, making the storage more difficult than that in room temperature, so storage and transport in distribution of agricultural products needs specialty. In addition, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. However, existing distribution system of agricultural products is exposed to various problems including problems in distribution channel, making distribution and strategy for distribution and those problems are as follows. First, in case of investment in overseas agricultural industry, stable supply of the products is difficult because areas of production are dispersed widely and influenced by outer factors due to including overseas distribution channels. Also, at the aspect of quality, standardization of products is difficult, distribution system is quite complicated and unreasonable due to long distribution channels according to international trade and financial and institutional support is not enough. Especially, there are quite a lot of ineffective factors including multi level distribution process, dramatic gap between production cost and customer's cost, lack of physical distribution facilities and difficulties in storage and transport due to lack of wrapping containers. Besides, because import and export of agricultural products has been manages under the company's own distribution according to transaction contract between manufacturers and exporting company, efficiency is low due to excessive investment in fixed costs and lack of specialty in dealing with agricultural products causes fall of value of products, showing the limit to lose price-competitiveness. Especially, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. Second, among tangible and intangible services which promote the efficiency of the whole distribution, a function building distribution environment which includes distribution information, system for standard and inspection, distribution finance, system for diversification of risks, education and training, distribution administration and tax system is wanted. In general, such a function building distribution environment is difficult to be changed and supplement innovatively because its effect compared with investment does not appear immediately despite of its necessity. Especially, in case of distribution of agricultural products, as a function of collecting and distributing is performed individually through various channels, the importance of distribution information and standardization is getting more focus due to the problem of repetition of work and lack of specialty. Also, efficient management of distribution is quite difficult due to lack of professionals in distribution, so support to professional education is needed. Third, though effort to keep self-sufficiency ratio of staple food, rice is regarded as important at the government level, level of dependency on overseas of others crops is high. Therefore, plan for stable securing food resources aside from staple food is also necessary. Especially, governmental organizations of agricultural products distribution in Korea are production-centered and have unreasonable structure whose function at the aspect of distribution and consumption is quite insufficient. And development of new distribution channels which can deal with changes in distribution environment and they do not achieve actual results of strategy for distribution due to non-positive strategy for price distribution. That is, it implies the possibility that base for supply will become vulnerable because it does not mediate appropriate interests on total distribution channels such as manufacturers, wholesale dealers and vendors by emphasizing consumer protection excessively in the distribution of agricultural products. Therefore, this study examined fundamental concept and actual situation for our investment to overseas agriculture, drew necessities, considerations, problems, etc. of overseas agricultural investment and suggested improvements at the level of distribution for price competitiveness of agricultural products cultivated in overseas under five aspects; government's indirect support, distribution's modernization and distribution information function's strengthening, government's political support for distribution facility, transportation route, load and unloading works' improvement, price competitiveness' securing, professional manpower's cultivation by education and training, etc. Here are some suggestions for foreign produce importation. First, the government should conduct a survey on the current distribution channels and analyze the situation to establish a measure for long-term development plans. By providing each agricultural area with a guideline for planning appropriate production of crops, the government can help farmers be ready for importation, and prevent them from producing same crops all at the same time. Government can sign an MOU with the foreign government and promote the importation so that the development of agricultural resources can be stable and steady. Second, the government can establish a strategy for an effective distribution system by providing farmers and agriculture-related workers with the distribution information such as price, production, demand, market structure and location, feature of each crop, and etc. In order for such distribution system to become feasible, the government needs to reconstruct the current distribution system, designate a public organization for providing distribution information and set the criteria for level of produce quality, trade units, and package units. Third, the government should provide financial support and a policy to seek an efficient distribution channel for foreign produce to be delivered fresh: the government should expand distribution facilities (for selecting, packaging, storing, and processing) and transportation vehicles while modernizing old facilities. There should be another policy to improve the efficiency of unloading, and to lower the cost of distribution. Fourth, it is necessary to enact a new law covering exceptional cases for importing produce in order to maintain the price competitiveness; currently the high tariffs is keeping the imported produce from being distributed domestically. However, the new adjustment should be made carefully within the WTO regulations since it can create a problem from giving preferential tariffs. The government can also simplify the distribution channels in order to reduce the cost in the distribution process. Fifth, the government should educate distributors to raise the efficiency and to modernize the distribution system. It is necessary to develop human resources by educating people regarding the foreign agricultural environment, the produce quality, management skills, and by introducing some successful cases in advanced countries.

• Journal of Korean Society of Forest Science
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• v.42 no.1
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• pp.1-38
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• 1979

The woody species of Genus Ilex which are endemic to Korea are distributed on limited area due to solely temperature factor. There is some differences according to species, however in general, the evergreen Ilex are found along southern coastal area of Korean Peninsula and near islands where the cold index does not exceed $-5^{\circ}C$. But Ilex macropoda and the variety, only deciduous ones, are grown in temperate zone of the peninsula and some islands. The list of Ilex species of Korea are as follows. Ilex cornuta Lindley et Pax., I. crenata Thunb. var. microphylla Max., I. crenata Thunb., I. rotunda Thunb., I. macropoda Miq., I. macropoda Miq. var. pseudo-macropoda Loensner, I. integra Thunb. The author surveyed the populations of Ilex species as many as possible and data of some characters such as leaf shape, spine, fruit shape, stomata density, sex ratio in natural communities, etc. are collected. Almost all the Ilex species in Korea show sporadic distribution. This means quite small sized populations isolate distantly each other eliminating the change of gene exchange in between. Particularly Ilex conuta and I. crenata show the morphological differentiation among populations as well as significant individual variation within a population. These were true with such characteristics, leaf shape, leaf dimension, leaf margin, fruit shape, spine, and stomata density. The founded are that the fruit length and the stomata density counted on the beneath surface of leaves of Ilex cornuta increased with the decrease of latitude. These are naturally closely related with the cold index values. The table shown below indicates the correlation between mean stomata density per $0.3642mm^2$ and cold index values. These relation however were not observed on Ilex crenata. The most dominated natured in relation to individual variation were outline of leaf, the number of marginal spine, the shape of leaf cross section and the degree of luster of the upper leaf surface. As shown in photos 5~7, these variations are agreed at a glance. There are reports that the development of marginal spines in some Ilex species is associated with the juvenility and topophysis. In present study, these two factors were neglected because of the intended sampling procedure. Of Ilex rotunda, population difference with the characteristics of leaf length is recognized but not for leaf width, petiole length, and fruit size. However, individual variations within a population were significantly large. In case of Ilex integra, only individual differences within population were calculated statistically for such characteristics as leaf length, leaf width, and petiole length. As to natural population, the sex ratio was 1:2 (female to male) for Ilex cornuta, and 1:1 for Ilex crenata. The tendency of more male than female in I. cornuta was agreed to other observations. Preparing the tip cutting of length 10cm, and treating with IBA, then attaching earth ball to the cut end, very successful rooting percentages were obtained. Asexual propagation has the advantages of maintaining the heterozygosity of existing varieties and overcoming the difficulties of delayed seed germination frequently encountered with Ilex species. Considering a great deal of variation in morphological traits, a good possibility of selection breeding for decorative and ornamental purposes exists. At present, these evergreen Ilex are ignored by local people as nuisance weedy shrubs. So the proper protection measures should promptly be taken.

• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.537-548
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• 2017

The purpose of this study was to investigate the species composition and the aquatic environment of Jojong Stream and Sudong Stream, which were the original habitats of Zacco koreanus population and restored population re-introduced in Bongseonsa Stream. It also compared and analyzed the states of the growth and reproductive ability of Z. koreanus habiting in each of the three streams. The investigation was conducted in June 2016 which was known as the spawning season of Z. koreanus. The results of the physical aquatic environments showed the slight differences in altitude, width and depth of water among three streams, but the bottom structure was found to be quite different in the composition of the boulder, cobble, and pebble among the streams. The result of the physicochemical aquatic environment analysis showed that there were no significant differences in water temperature, pH, DO, BOD, and EC among the three stream. In the fish fauna investigation, 530 individuals of 11 species of 3 families were collected in Bongseonsa Stream, 293 individuals of 12 species of 4 families were collected in Jojong Stream, and 361 individuals of 11 species of 4 families were collected in Sudong Stream. All three streams were dominated by Z. koreanus and Z. platypus. Six Korean endemic species appeared in each of the three streams, showing the high occurrence rate of indigenous species of 50.0% or more. The aggregation index analysis revealed that the mean dominance index ranged from 0.63 (${\pm}0.05$, BS) to 0.72(${\pm}0.01$, JJ), mean diversity index from 1.55 (${\pm}0.06$, JJ) to 1.78 (${\pm}0.11$, BS), mean evenness index from 0.71 (${\pm}0.03$, JJ) to 0.76 (${\pm}0.02$, BS), and mean richness index from 1.61 (${\pm}0.33$, JJ) to 1.73 (${\pm}0.24$, SD). The result indicated that the observed differences between the stream community indices were statistically nonsignificant. The similarity analysis showed that 75.4% similarity was divided into two groups of A and B and that the fish fauna on each analyzed point was similar. The quantitative habitat evaluation index (QHEI) analysis showed that the average value of QHEI was 151.0 (${\pm}46.0$), which means that it was a suboptimal habitat environment. The result of length-weight analysis of Z. koreanus populations showed that the regression coefficient b of the restoration population and the original habitat population were at 3.0 or higher while the condition factor had a positive slope. Moreover, it was found that the slopes of the regression coefficient b and condition factor of the original habitat population were larger than the restored population. The analysis of the length frequency distribution of the Z. koreanus population revealed that all three streams maintained the stable life cycle although it was found that the growth rate of the original habitat population was faster than the restored population in the one-year-old class. The result of the gonadosomatic index (GSI) analysis showed that the GSI median value of the Z. koreanus population in the restored habitat Bongseonsa Stream was higher than the population in the original habitat Jojong Stream and Sudong Stream for both of males and females.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.59-68
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• 1995

Investigated were the relationships between plumule elongation characteristics and seedling emergence of 46 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, India, Japan under 1, 3, and 5cm deep sowing with irrigated and non-irrigated condition. Experiments were carried out in paddy field of sandy loam. There was heavy shower of 19.2mm on the next day of seeding and thereafter, clear and dry weather continued during the experiment period. Soil temperature averaged over 30 days after seeding was $16.4^{\circ}C$ at 3cm depth. Soil hardness increased linearly up to 2.5kg /$cm^2$ on the 14th day after seeding, on which date irrigated plot was irrigated through furrow, and up to 4kg / $cm^2$ on the 28th day in non-irrigated plot. Soil hardness dropped near to 0kg /$cm^2$ after irrigation and developed up to 2.5kg /$cm^2$ again by 28 days after seeding. Seedling emergence was higher in irrigated plots than non-irrigated plots at all seeding depths. Korean improved varieties were substantially lower in seedling emergence under non-irrigated condition of 1 cm deep sowing than those under irrigated condition. This poor seedling emergence resulted mainly from delayed emergence by exposing them to greater soil strength. Percent seedling emergence under irrigated and non-irrigated condition showed signifi-cant correlations at 3 and 5 cm deep sowing. Korean improved varieties belonged to the group of poor seedling emergence, and I taliconaverneco, Chinsura Boro and Weld Pally to best group under both irrigation conditions at 3 and 5cm deep sowing. Seedling emergence showed highly signifi-cant positive correlation with the plumule length of mesocotyl ＋ 1st internode ＋ incomplete leaf and of mesocotyl＋coleoptile. Among the characters constituting plumule length, incomplete leaf length showed greatest positive correlation followed by coleoptile and mesocotyl under irrigated condition at 3 and 5 cm deep sowing, and highest correlation with mesocotyllength followed by first internode and incomplete leaf under non-irrigated condition. Days to 50% seedling emergence at 1 cm deep sowing with irrigation showed great varietal variation of 10 to 30 days, and showed high significant negative correlations with percent seedling emergence under both irrigation conditions except for 1 cm deep sowing with irrigation, Days to seedling emergence revealed sig-nificant negative correlations with plumule characters except 2nd internode, showing highest cor-relation with incomplete leaf length.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.465-478
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• 1995

The objective of this study was to investigate the impacts of large-scale timber harvesting on the environment of a mature hardwood forest. To achieve the objective, the effects of harvesting on forest environmental factors were analyzed quantitatively using the field data measured in the study sites of Seoul National University Research Forests [(Mt.) Paekunsan] for two years(1993-1994) following timber harvesting. The field data include information on vegetation, soil mesofauna, physicochemical characteristics of soil, surface water runoff, water quality in the stream, and hillslope erosion. For comparison, field data for each environmental factor were collected in forest areas disturbed by logging and undisturbed, separately. The results of this study were as follows : The diversity of vegetational species increased in the harvested sites. However, the similarity index value of species between harvested and non-harvested sites was close to each other. Soil bulk density and soil hardness were increased after timber harvesting, respectively. The level of organic matter, total-N, avail $P_2O_5$, CEC($K^+$, $Na^+$, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$) in the harvested area were found decreased. While the population of Colembola spp., and Acari spp. among soil mesofauna in harvested sites increased by two to seven times compared to those of non-harvested sites during the first year, the rates of increment decreased in the second year. However, those members of soil mesofauna in harvested sites were still higher than those of non-harvested sites in the second year. The results of statistical analysis using the stepwise regression method indicated that the diversity of soil mesofauna were significantly affected by soil moisture, soil bulk density, $Mg^{{+}{+}}$, CEC, and soil temperature at soil depth of 5(0~10)cm in the order of importance. The amount of surface water runoff on harvested sites was larger than that of non-harvested sites by 28% in the first year and 24.5% in the second year after timber harvesting. The level of BOD, COD, and pH in the stream water on the harvested sites reached at the level of the domestic use for drinking in the first and second year after timber harvesting. Such heavy metals as Cd, Pb, Cu, and organic P were not found. Moreover, the level of eight factors of domestic use for drinking water designated by the Ministry of Health and Welfare of Korea were within the level of the first class in the quality of drinking water standard. The study also showed that the amount of hillslope erosion in harvested sites was 4.77 ton/ha/yr in the first year after timber harvesting. In the second year, the amount decreased rapidly to 1.0 ton/ha/yr. The impact of logging on hillslope erosion in the harvested sites was larger than that in non-harvested sites by seven times in the first year and two times in the second year. The above results indicate that the large-scale timber harvesting cause significant changes in the environmental factors. However, the results are based on only two-year field observation. We should take more field observation and analyses to increase understandings on the impacts of timber harvesting on environmental changes. With the understandings, we might be able to improve the technology of timber harvesting operations to reduce the environmental impacts of large-scale timber harvesting.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.217-223
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• 2010

This study was conducted to reclassify Dongsong series based on the second edition of Soil Taxonomy and to discuss the formation of Dongsong series distributed on the lava plain at Cheolweon in Korea. Morphological properties of typifying pedon of Dongsong series were investigated, and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Dongsong series has brown (7.5YR 4/2) silty clay loam Ap horizon (0-16 cm), brown (7.5YR 4/2) silty clay loam BA horizon (16-22 cm), brown (7.5YR 4/2) silty clay Bt1 horizon (22-50 cm), reddish brown (5YR 5/4) silty clay Bt2 horizon (50-92 cm), and brown (7.5YR 4/3) silty clay loam Bt3 horizon (92-120 cm). It occurs on lava plain derived from baslt materials. The typifying pedon has higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to more than 120 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Andisol or Alfisol. It has aquic conditions for some time in normal years in one or more horizons within 50 cm of the mineral soil surface, redoximorphic features between a depth of 25 cm, and a depth of 40 cm from the mineral soil surface, and redox concentrations, and 50%or more redox depletions with chroma of 2 or less in the matrix within the upper 12.5 cm of the argillic horizon. Therefore it can be classified as Aquult. It has episaturation, and keys out as Epiaquult. It has 50% or more chroma of 3 or more in one or more horizons between a depth of 25 cm from the mineral soil surface, and a depth of 75 cm. It can be classified as Aeric Aquult. Dongsong series have 35%or more clay at the particle-size control section, and have mesic soil temperature regime. Therefore they can be classified as fine, mesic family of Aeric Epiaquults, not as fine, mesic family of Typic Epiaqualfs. The Quarternary volcanic activities occurred in Jeju Island, Ulrung Island, Baekryeong Island, Cheolweon area, and Mt. Paekdu et al. in the Korean Penninsula. Most of them belong to the central eruption type, but Cheolweon area may be of the fissure eruption type. Dongsong series occur on Cheolweon lava plains derived from basaltic materials. Most soils distributed in Jeju Island, and derived from mainly pyroclastics are developed as Andisols. But Dongsong series distributed in Cheolweon lava plains which have a relatively dry climate and derived from basaltic materials are developed as Ultisols.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.664-676
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• 2019

This study aimed to analyze the bioacoustics and habitat environment of the cicadas inhabiting Taebaeksan National Park, an sub-alpine region in Korea. The mating calls of the cicadas were recorded for approximately 3 months, between July and September of 2018. The recording devices were installed in Daedeoksan valley and Baekcheon valley, inside Taebaeksan National Park, and the sounds were recorded 24 hours a day. In order to obtain the habitat distribution data of the cicadas, the sounds were recorded from 111 spots located in the Taebaeksan National Park trail in August 2018. The daily weather data was obtained from the Taebaek city weather center. The results of the study demonstrated that 5 species of cicadas inhabit Taebaeksan National Park, namely, Leptosemia takanonis, Lyristes intermedius, Kosemia yezoensis, Hyalessa fuscata, and Meimuna opalifera. The time of appearance for L. takanonis was early July to mid-July, and that for L. intermedius, K. yezoensis, H. fuscata, and M. opalifera was mid-July to early September. Analysis of the circadian rhythm revealed that L. intermedius, K. yezoensis, and H. fuscata started producing mating calls between 6:00 and 7:00, which ended at around 19:00 for all the three species. The peak time for producing mating calls was 11:00 for L. intermedius, 12:00 for H. fuscata, and around 13:00 to 14:00 for K. yezoensis. The environmental factors influencing the mating calls of the cicadas inhabiting Taebaeksan National Park were analyzed by logistic regression. The results showed that the probability of producing mating calls increased by 1.192 and 1.279 times in L. intermedius and K. yezoensis, respectively, when the average temperature increased by one degree. When the duration of sunlight increased by one hour, the probability of producing mating calls increased by 4.366 and 2.624 times in L. intermedius and H. fuscata, respectively. Analysis of the interspecific effects revealed that when H. fuscata produced a single mating call, the probability of producing mating calls increased by 14.620 and 2.784 times in L. intermedius and K. yezoensis, respectively. When K. yezoensis and L. intermedius produced mating calls, the probability of producing mating calls in H. fuscata increased by 11.301 and 2.474 times, respectively. L. intermedius and K. yezoensis did not have any effects on each other with respect to the production of mating calls. Analysis of the habitat environment of each species revealed that their habitats were located at altitudes of 1,046 m (780~1,315 m) for L. intermedius, 1,072 m (762~1,361 m) for K. yezoensis, and 976 m (686~1,245 m) for H. fuscata. Unlike H. fuscata, which was found at a low altitude, K. yezoensis and L. intermedius were not found at altitudes lower than 700 m. Analysis of the average aspect of the habitats of each of the cicada species revealed that L. intermedius was found at 166° (125~207°), K. yezoensis was found at 100° (72~128°), and H. fuscata was found at 173° (118~228°). Examination of the distribution of each of the cicada species revealed that they were predominantly distributed in the ridges and slopes located in the southeastern region of Munsubong in Taebaeksan. In summary, L. intermedius and K. yezoensis was found to inhabit higher altitudes in Taebacksan National Park than H. fuscata, which was found throughout the Korean peninsula. Additionally, the main aspect of the cicada habitat was found to be the southeastern region (100~173°), which has good access to daylight.

• Journal of Korean Society of Forest Science
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• v.10 no.1
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• pp.29-39
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• 1970

Forest fires often destory forests that have taken years to grow in a few minutes. Forest fire therefore, is an important problem in forest management and have caused heavy losses to the nations economy. In order to resolve this problem many investigations have been made in many countries. However, ecological studies on the forest after accidental fire have not yet been made in Korea. In order to conduct such a study, a burned area on Mt. Samak which is located at Dukduwon-ri, Seo-myon, Chunsung-gun, Kangwon-do, was chosen as experimental plot in 1967. The remaining seeds were collected from the burned area, and investigations on their germination rate and their productivity were made comparing to those of the seeds of undemaged area, and following results were obtained. 1. The number of seed collected from the control plots were 740 while it was 537 from the test plots (Table 3, 4). It was considered that this difference between burned and unburned area was mainly due to the fact that some of the seeds had been burnt by the fire, and the unfavorable environmental conditions in the burned area was also considered to be a reason. In the germination rate in the control plots showed 28.1% while it was 3.2% in the test plots. This difference was considered to be due to complete loss of viability of the seed by burning and high heat. 2. In the test plots, sixteen seeds of the Alnus japonica were collected and six of these seeds germinated (index number 100) which was the highest germination rate among the species of collected seeds. From these results, it was considered that a high temperature (above $150^{\circ}C$) caused reduction of the germination rate (Quadrat. 1.2). Seeds of Carex lanceolata var. Nana, were appeared much more in the higher plots than in the lower plots and it seemed to be due to the fact that the forest floor plants were much more abundant in the lower plots than in the higher plots which is covered with shrubbery. And some small seeds midght be able to avoid the effect of fire being burried in the soil or under the gravel. 3. With Pinus densiflora, 43 seeds were collected, and 11 of these germinated in the control plots. However in the test plots, 11 seeds were collected and no seed germinated. This shows that the Pinus densiflora was the weakest in resisting to heat among the observed species in this study. 4. Without exception the germination rate showed a higher index in the herbs than in the woody plants and it is believed that the herbs produced more seed than the wood plants because of the abundance of herbs colony.