• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.52-61
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• 2011

Whereas recent researches have elucidated the positive ecological roles of large wood (LW) in fishbearing channels, LW is also recognized as a negative factor of log-laden debris flows and floods in densely populated areas. However in Republic of Korea, no study has investigated longitudinal variations of LW distribution and dynamic along the stream corridor. Hence to elucidate 1) physical factors controlling longitudinal distribution of LW and 2) their effect on variation in LW load amount, we surveyed the amount of LW with respect to channel morphology in a mountain stream, originated from Mt. Ki-ryong in Inje, Gangwondo. Model selection in the Generalized Linear Model procedure revealed that number of boulder (greater than or equal to 1.0 m in diameter), bankfull channel width and their interaction were the best predictors explaining LW load volume per unit channel segment area (unit LW load). In general, boulders scattered within small mountain streams influence LW retention as flow obstructions. However, in this study, we found that the effect of the boulders vary with the channel width; that is, whereas the unit LW load in the segment with narrow channel width increased continuously with increasing boulder number, it in the segment with wide channel width did not depend on the boulder number. This should be because that, in two channels having different widths, the rates of channel widths reduced by boulders are different although boulder numbers are same. Our findings on LW load varying with physical factors (i.e., interaction of boulder number and channel width) along the stream corridor suggest understanding for longitudinal continuum of hydrogeomorphic and ecologic characteristics in stream environments, and these should be carefully applied into the erosion control works for systematic watershed management and subsequent disaster prevention.

• Ecology and Resilient Infrastructure
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• v.8 no.1
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• pp.64-78
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• 2021

This study was conducted to find out the effect of the construction and operation of river-crossing structures on the habitat landscape characteristics in the Geum-gang River, South Korea. A total of three study reaches were selected in the downstream of the Daecheong Dam: the Buyong-ri reach, which is a control that is not affected by the construction and operation of the weir of the Four Rivers Project and Sejong-bo Weir reach and Gongju-bo Weir reach of the upper and lower sections of each weir that are affected by the weir construction and operation. The habitat type was classified, and then the structural characteristics of the landscape were analyzed using aerial photographs taken before and after the construction of the Daecheong Dam, before and after the construction of the weir, and before and after the weir gate operation. After the construction of Daecheong Dam in Geum River, the area of the bare land greatly decreased, and the area of grassland and woodland increased in the downstream of the dam. In addition, the patch number in the river landscape increased, the patch size decreased, and the landscape shape index and the habitat diversity increased. Therefore, after the construction of the dam, the bare land habitat was changed to a vegetated habitat, and the habitat was fragmented and diversified in the downstream of the dam. After the construction of the weirs, the area of open water increased by 18% in the Sejong-bo reach and by 90% in the Gongju-bo reach, and the landscape shape index of the open water decreased by 32% in the Sejong-bo reach and by 35% in the Gongju-bo reach, and the habitat diversity index decreased to 25% in the Sejong-bo reach and to 24% in the Gongju-bo reach. Therefore, the open water habitat was expanded, the shape of the habitat was simplified, and the habitat diversity decreased according to the construction of the weirs. After water-gate opening of the weir, the bare land that disappeared after the construction of the weir reappeared, and the landscape shape index and habitat diversity index increased in both terrestrial and open water habitats. Therefore, it was found that the landscape characteristics of the river habitats were restored to the pre-construction of the weir by the operation of the weir gate. The effect of weir gate opening was delayed in the downstream than in the upstream of the weir. Although the characteristics of the landscape structure in the river habitat changed due to the construction of the river-crossing structures, it is thought that proper technology development for the ecological operation of the structures is necessary as the habitat environments can be restored by the operation of these structures.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.3
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• pp.1-11
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• 2013

In this study, based on a natural monument forest research by Camellia japonica L. Forest appointed as a natural monument located environment and growth environment and the soil environment, Camellia japonica L. Forest soil in order to analyze effects of soil in Camellia japonica L. Forest correlation analysis the results can be summarized as follows: First, a natural monument Camellia japonica L. forest located on the foot of a mountain valley or within the stream, a lot of sunshine southeast, east, and south in the direction of the share due to external factors, making it a good, but, $15{\sim}30^{\circ}$ of distributed in the soil slopes in the slope there is a risk of loss are appearing. Second, the growth of the Status of Camellia japonica L. forest represents the distribution of the uneven-aged forest diameter class. but increases the density of the upper forest trees Camellia japonica L. occurred in lower saplings do not have growth. The width of crown diameter class caused a narrow oppressed tree, the average tree height in the 8.09m, camellia in common was lower than that of tree height, variation diameter class in the width of crown distribution severe low correlations were analyzed. Third, the natural monument Camellia japonica L. forest soil composition, properties of soil pH, etc. 10 entries were analyzed components of the soil. In summary analysis properties of soil, soil pH, calcium, organic matter, magnesium was good and potassium content was insufficient, nitrogen and phosphorus were excess. Fourth, the growth condition of Camellia japonica L. forest and soil physicochemical properties, the results of the correlation analysis. magnesium, calcium, nitrogen affects the growth of Camellia japonica L. forest. Other seven kinds of items showed no effect on growth. Current Status and Future Growth of Camellia japonica L. forest soil and soil environments as well as the relationship between, Camellia Forest Factors affecting the growth of the state in terms of long-term ecological research and conservation status of settled Camellia japonica L. forest research for building materials there will be continued.

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.63-71
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• 2020

This study characterized the spatial and seasonal patterns of light pollution in the Deogyusan National Park and examined the potential effects of light pollution on ecosystems in the park using light intensities derived from VIIRS (Visible Infrared Imaging Radiometer Suite) DNB (Day and Night Band) nightlight images collected in January and August 2018. Results showed that the Muju Deogyusan resort had the greatest light intensity than other sources of light pollution in the park, and light intensity of the resort was much higher in January than in August, suggesting that artificial lights in ski slopes and facilities were the major source of light pollution in the park. An analysis of an urban-natural light pollution gradient along a neighboring urban area through the inside of the park indicated that light radiated from a light pollution source permeated for up to 1km into the adjacent area and contaminated the edge area of the park. Of the legally protected species whose distributions were reported in literature, four mammals (Martes flavigula, Mustela nivalis, Prionailurus bengalensis, Pteromys volans aluco), two birds (Falco subbuteo, Falco tinnunculus), and nine amphibians and reptiles (Onychodactylus koreanus, Hynobius leechii, Karsenia koreana, Rana dybowskii, Rana huanrenensis, Elaphe dione, Rhabdophis tigrinus, Gloydius ussuriensis, Gloydius saxatilis) inhabited light-polluted areas. Of those species inhabiting light-polluted areas, nocturnal species, such as Prionailurus bengalensis and Pteromys volans aluco, in particular, were vulnerable to light pollution. These results implied that protecting ecosystems from light pollution in national parks requires managing nighttime light in the parks and surrounding areas and making a plan to manage nighttime light pollution by taking into account ecological characteristics of wild animals in the parks.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.74-85
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• 1995

A study was conducted to provide some basic data for controlling the Mulberry scale insect(Pseudaulacaspis pentagona T.). Experiments were carried out with checking their field-life, and a few selected insecticides were tested when mulberry leaves were not in use. About 57% of female were survived from the overwintering attached to the bark. Over 80% of the scale were distributed within the range of 30cm from the base of each stem. One hundred percent and 96.7% of eggs were hatched under 25$^{\circ}C$ and 27$^{\circ}C$ respectively. Eighty percent of pupae emerged both under 25 and 27$^{\circ}C$. The Mulberry scale require about 33 days under 25$^{\circ}C$ and 30 days under 27$^{\circ}C$. This species had 2 generations each year in mulberry field in Suwon. Overwintered as a mated female only. Oviposited about 170 eggs under their scale starting from the late April (in 1994) through the mid May (in 1993). Phenthoate EC sprayed in the mid June against the larvae was very effect with over 96% of control value.

• Journal of Life Science
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• v.9 no.4
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• pp.395-407
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• 1999

The queens of Korean native bumblebee species, Bombus ignitus were collected from the field in the spring of 1997 and reared under the various temperatures as 15$^{\circ}C$$\pm$1$^{\circ}C$, 2$0^{\circ}C$$\pm$1$^{\circ}C$, $25^{\circ}C$ $\pm$1$^{\circ}C$, 3$0^{\circ}C$$\pm$1$^{\circ}C$, 60%$\pm$5% of relative humidity and 14L : 10D, to investigate their ecological characteristics, as comparing with control(29$^{\circ}C$$\pm$1$^{\circ}C$, 60%$\pm$5% of relative humidity and red light). As a result, eggs were laid by foundation queen at 15$^{\circ}C$, but they didn't hatched out while at 2$0^{\circ}C$ eggs were laid by them and they hatched out. When a foundation queen laid eggs at $25^{\circ}C$ and they all were hatched out and normally grown. Finally they were developed to the normal colony. B. ignitus worker survived for 77days at 2$0^{\circ}C$, about 69days at $25^{\circ}C$, about 68days at 3$0^{\circ}C$ and about 63days at 29$^{\circ}C$(control). The first brood workers emerged in 25-27days from the egg which a foundation queen laid. At the various temperatures, the captive queens stand to lay eggs in about 18days at 15$^{\circ}C$, 15days at 2$0^{\circ}C$, 11days at $25^{\circ}C$, 11days at 3$0^{\circ}C$ and 4days in control. The first worker and the first drone from the egg cell of the collected queens appeared in about 27days and 72days at 2$0^{\circ}C$, 26days and 88days in $25^{\circ}C$, 24days and 65days at 3$0^{\circ}C$, 25days and 71days in control, respectively. In colony foundation, 33% of the collected queen at 2$0^{\circ}C$ and $25^{\circ}C$, 100% of the disposed queen at 3$0^{\circ}C$ and in control, and 67% of them at 3$0^{\circ}C$ and in control both produced new queens in 66days and 88days, respectively. The life span of the colony founded covered fro about 3 months at $25^{\circ}C$, 3$0^{\circ}C$ and in control. At lower temperatures, the life span of queen is shorter; 2 months at 15$^{\circ}C$ and 3 months at 2$0^{\circ}C$, respectively. A colony which normally developed, varied in size with rearing temperatures; about 20heads at 2$0^{\circ}C$, 482heads at $25^{\circ}C$, 330heads at 3$0^{\circ}C$ and 452heads in control. A foundation queen monthly oviposited 1.5egg cells at 15$^{\circ}C$, 3.0egg cells at 2 $0^{\circ}C$, 21.7egg cells at $25^{\circ}C$, 42.3egg cells at 3$0^{\circ}C$ and 47.0egg cells in control. As a colony developed in June and July, egg cells as well as daily average cells increased in number, as compared to those in May and August. Also, in June and July, interval(days) of egg laying is shorter than in May and August. Number of nectar pots during the colony development varied with rearing temperatures; 31pots at $25^{\circ}C$, 39pots at 3$0^{\circ}C$, 23pots in control. The emergence of new queen showed a distinctively different two patterns; early emerging type and late emerging type. Workers are rapidly increased from early in July to early in August at $25^{\circ}C$, but at 3$0^{\circ}C$ and in control, emergence of workers are remarkably increased from the middle of June and last until July. No new queen emerged at 15$^{\circ}C$, 2$0^{\circ}C$ and $25^{\circ}C$. New queens at 3$0^{\circ}C$ and in control emerged between late in June and early in July. Thus emergence of new queen was temperature dependent.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.119-141
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• 2000

The current industrial health service is shifting to health improvement business with 1st primary prevention-focused service from secondary and tertiary prevention-focused business, and Oriental medicine can provide such primary prevention-focused service due to the characteristics of its science. In particular, the advanced concept of health improvement can match the science of health care of Oriental medicine. Notably, what is most important in health improvement is our lifestyle, This does not underestimate the socio-environmental factors, which have lessened their importance due to modernism. The approach of Oriental medicine weighs more individuals' lifestyle and health care through self-cultivation. This matches the new model of advanced health business. Oriental medicine is less systemized than Western medicine, but it can provide ample contents that enhance health. If we conceive health-improvement program based on the advantages provided by these two medical systems, this will influence workers to the benefit of their health. Also, health Program needs to define factors that determine individual lives, and to provide information and technologies essential to our lives. The Oriental medicine approach puts more stress on a subject's capabilities than it does on the effect his surrounding environment can have. This needs to be supported theoretically by not only defining the relations between an individual's health state and his lifestyle, but also identifying the degree to which an individual in the industrial work place practices health improvement lifestyle . This is the first step toward initiating health-improvement business . In order to do this, this researcher conducted a survey by taking random samplings from workers, and can draw the following conclusions from it. 1 The sampled group is categorized into', by sender, female 6.6%, and male 93.4%, with males dominant; by marriage status , unmarried 43.9% and married 55.6%, with both similar percentage, and, by age, below 30, 48.4%, between 30 and 39, 27.4%, between 40 and 49, 18.2%, and over 50, 6.0%. The group further is categorized into; by education, middle school or under 1.7%, high school 30.5%, and junior college or higher 65.8% with high school and higher dominant: and by income, below 1.7 million won 24.2%, below 2.4 million won 14.8%, and above 2.4 million 6.3% Still, the group by job is categorized into collegians with 23.9%, office worker with 10.3%, and professionals with 65.8% , and this group does not include workers engaged in production that are needed for this research, but mostly office workers . 2. The subjects selected for this survey show their degree of practicing health-improvement lifestyle at an average of 2.63, health management pattern at 2.64, and health-related awareness at 2.62 The sub-divisions of health-improvement lifestyle show social emotion (2.87), food (2.66). favorite food (2.59), and leisure activities (2.52), in this order for higher points. It further shows health awareness (2.47) and safety awareness (2.40), lower points than those in health management pattern . 3. In the area of using leisure time for health-improvement, males, older people, married, and people with higher income earn higher marks. And, in the area of food management, the older and married earn higher marks . In the area of favorite food management, females, lower-income bracket, and lower-educated show higher degree of practice , while in the area of social emotion management, the older. married, and higher-income bracket show higher marks. In addition, in the area of health awareness, the older, married, and people with higher-income show higher degree of practice. 4. To look at correlation by overall and divisional health-improvement practice degree , this researcher has analyzed the data using Person's correlation coefficient. The lifestyle shows significant correlation with its six sub-divisions, and use of leisure time, food, and health awareness all show significant correlation with their sub-divisions. And. the social emotion and safety awareness show significant correlation with all sub-divisions except favorite food management.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.11-26
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• 1964

The studies reported herein are on the varietal differences of rice in the effects of seeding times and nursery periods on the components such as, culm length, ear length, number of ears, ear weight, straw weight, and grain/straw ratio following the first series of studies on heading date. In the present investigations, 50 rice varieties, as the preceding studies, were seeded nine times at the interval of 15 days from March 15 to July 28 in 1963. Each variety seeded at respective time was transplanted in 40 days in nursery after seeded. Reviewing the result obtained from the first series of the studies on heading date, the number of days required to heading from seeding were decreased by delaying the seeding time. Most varieties tended to decrease in the number of days from seeding to heading by the 8th planting time. Some of varieties seemed to be decreased in the number of days from seeding to heading by 9th seeding time. However most varieties were failed to show heading delaying the seeding date at the 10th seeding. The results on the effects of altering the seeding time on the components and varietal differences of the response are summarized as follows; 1) Culm length; It appeared that culm length was shortened when the number of days from seeding to heading was decreased by delaying the seeding date. The varieties which needed many days to heading were also shortened in their culm length. 2) Ear length; Ear length was also shortened when the number of days needed tocheading was decreased, by delaying the seeding time. The varieties which needed many days for heading were also shortened in their ear length, while those which headed earlier seemed to be lengthened in their ear lengths. 3) Number of ears; It was shown that the number of ears was increased with the delay of the heading date, whereas, at the 9th seeding the number of ears was decreased when delayed the heading date. 4) Ear weight; Ear weight per hill was also likely to be heavy throughout the seeding times and varieties except the 7th and 8th seedings in which it appeared to be light on the contrary. 5) Straw weight; Straw weight became heavier as delayed the seeding date throughout all the varieties and seeding dates. 6) The grain/straw ratio; The grain/straw ratio was gradually increased by the 5th seeding time, reaching the pick at 5th. An examination of the varieties at each seeding date showed that the grain/straw ratio was low from 1st to 3rd seeding and from 7th to 9th seeding, when the number of days required to heading from seeding are increased. At the 4th seeding time-which is standard seeding time-5th, and 6th seeding times the ratio was high with the delay of heading.

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.33-41
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• 2009

The crushed fruiting body of Alaskan Porodaedalea pini (Brot.) Murrill (syn. Phellinus pini) was extracted in boiling water for 4 h with the yield of 20.5% in dry mass. This hot-water extract showed significant antiviral activity by inhibiting the plaque formation in HeLa cells by coxackievirus B3 (CVB3) and also showed highest inhibitory effect against neuraminidase activity among water extracts of various mushrooms. From the water extract, the ethanol precipitate (EP) and supernatant fraction (ES) were obtained through 75% ethanol precipitation with the yield of 43.3% and 28.3% in dry mass, respectively. Whereas ES did not show any detectable level of antiviral activity, EP showed significant dose-dependent inhibition of plaque formation by CVB3 in HeLa cells with an $EC_{50}$ (50% effective concentration) of 0.45 mg/mL. The cytotoxicity on HeLa cells by EP was relatively low with the $CC_{50}$ (50% cytotoxic concentration) of 2.25 mg/mL. EP also effectively inhibited neuraminidase activity in a dose-dependent manner showing up to 75% inhibition at 1.7 mg/mL. These results suggest that the hot-water extract and its EP of P. pini fruiting body can be a candidate for the development of a potent broad-range antiviral agent against influenza virus(Flu) as well as CVB3. The major active component of EP was shown to be a heteropolysaccharide-protein complex containing glucose as the main sugar residue with mole percentage of 79.8% and other sugars like galactose (19.2%), xylose (17%), mannose (5.8%), and fucose (4.6%) and a small portion (12.7%, in mass) of protein.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.59-68
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• 2016

The application of the Life Cycle Assessment (LCA) methodology to assess the environmental impact of rapeseed cultivation in winter fallow after harvesting rice was investigated and compared with barley cultivation in crop rotation system. Data for input materials were collected and analyzed by 1 ton rapeseed and barley as functional unit. For the Life Cycle Impact Assessment (LCIA) the Eco-indicator 95 method has been chosen because this is well documented and regularly applied impact method. From the comparison of impact categories such as greenhouse effect, ozone depletion, acidification, heavy metals, carcinogens, summer smog, and energy resources for 1 ton of final product, emission potential from rapeseed was higher than that from barley. The range from 65 to 96% of these potential came from chemical fertilizer. On the other hand, eutrophication potential from barley was higher than that from rapeseed, mainly came from utilizing the chemical fertilizer. During the cultivation of barley and rape, environmental burden by heavy metals was evaluated by 0.5 Pt, larger than points from other impact categories. The sum of points from all impact categories in barley and rapeseed was calculated to be 0.78 Pt and 0.82 Pt, respectively. From the sensitivity analysis for barley and rapeseed, scenario 1 (crop responses to fertilization level) showed the environmental burden was continuously increased with the amount of fertilization in barley cultivation, while it was not increased only at the optimum crop responses to fertilization in rapeseed (R3). With these results, rapeseed cultivation in winter fallow paddy contributed to the amounts of environmental burden much more than barley cultivation. It is, however, highly determined that environmental weighted point resulted from evaluating both cultivation was not significantly different.