• Korean Journal of Organic Agriculture
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• v.29 no.1
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• pp.97-109
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• 2021

Plant parasitic nematodes are causing significant damage in crop production. There is a need to develop eco-friendly nematicide that reduces the damage of nematode and has little effect on the environment and human. In this study, we have isolated a substance having nematicidal activity from Ginkgo biloba L. outer seedcoat. Studies of G. biloba L. outer seedcoat are insufficient compared to the seed and leaves due to their odor and toxicity. The dried G. biloba L. outer seedcoat was extracted with dichloromethane:methanol (1:1) and fractionated into hexane, ethyl acetate and H₂O. Four steps TLC were performed from EtOAc fraction to purely isolate GB4-3 with nematicidal activity. To compare nematicidal activity, G. biloba L. seedcoat methanol extract and purified GB4-3 were investigated in terms of treatment concentration and time. As a result, the nematicidal activity increased with concentration and time. In the place treated with 20 ㎍/mL of crude G. biloba L. seedcoat MeOH extract, strong activity appeared after 12 hours, and 46% nematicidal activity shown after 18 hours. About 69% of nematicidal activity was confirmed in the place where GB4-3 purified from outer seedcoat was treated with 20 ㎍/mL, and the possibility of development as nematicide was very high. This study could be used as a basic data for the development of a nematode preparation from G. biloba L. outer seedcoat.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.202-203
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• 2001

거의 매년 우리나라 연안해역에서 푸른 바닷물이 갑자기 붉은색이나 황록색으로 변하는 적조 현상을 쉽게 관찰할 수 있다. 특히, 부영양화된 폐쇄성 및 반폐쇄성 내만 해역에서부터 해수유동이 원활한 외해역까지 광범위하게 매년 상습적으로 적조가 발생하여 어장환경과 수산생물에 막대한 피해를 일으키므로서 심각한사회ㆍ경제적인 문제를 야기시키고 있다(남해안 피조발생현황, 1995, 1996.; 한국연안의 적조발생 상황, 1997, 1998, 1999, 2000). (중략)

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.267-273
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• 2006

The biomass of Pinus densiflora stands burnt out by the 2005 Yangyang forest fire was estimated based on the grades of fire severity; light, moderate and heavy. In order to measure the post-fire ground biomass in kg/ha, the ground fuels including shrub layer were collected and weighted and the crown biomass was estimated using allometric regressions and leaf area index for dry weight of P. densiflora. The pre-fire biomass was assumed to be equal to that of non-damaged P. densiflora stands having the same characteristics. The results indicated that the forest fire burnt out fuels of stands; 3,693 kg/ha in the light-damaged, 8,724 kg/ha in the moderately-damaged, and 17,451 kg/ha in the heavily-damaged forest stands.

• Landscaping Tree
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• s.102
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• pp.26-28
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• 2008

최근 환경변화와 국제교류의 확대로 인하여 예전에는 문제가 되지 않았거나, 보이지 않았던 해충들이 문제해충화 되어 우리 주변에서 정원수나 조경수에 피해를 주는 해충들이 있다. 이들은 크게 3가지로 분류되는데 (1)환경의 변화에 의한 잠재해충과 문제해충화 (2) 인간의 욕심에 의해 대면적 식재로 인한 해충의 기회 확대 (3) 국제교류 확대로 인한 외래 해충의 침입 으로 나눌 수 있다. 이번 호에서는 환경변화에 의한 해충의 발생으로 환경스트레스에 의해 식물 자체 내의 방어체계가 무너지면 어떤 특정종이나 일반 해충이 대발생하는데 식물자체 환경 스트레스에 관계하는 jasmonate의 작용 저해, 식물이 자기방어를 위해 분비하는 타감물질(allelopathy)의 분비 억제, 초식성 곤충으로부터 산란억제를 위한 연모의 부족 등 해충의 대발생을 야기 시키는 경우도 있다. 또한 지구온난화로 인한 각종 해충의 대발생은 현재 전 세계적으로 문제가 되고 있다. 기온의 상승으로 곤충의 발육이 빨라져 화기 수가 증가한다거나, 포식자와 피식자의 상호작용의 연결고리가 깨어지는 등 각종 원인으로 인한 최근 발생한 해충을 기술하였다.

• Korean Journal of Environment and Ecology
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• v.16 no.4
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• pp.465-474
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• 2003

According to rapid increase of visitors to the Baekdudaegan, the most important ecosystem in Korea, fur climbing or outdoor recreation, deterioration of natural environment along the trail on the ridge of Baekdudaegan is becoming more serious. The purpose of this study is to research the deterioration condition of the trail between Manbokdae and Bokseongijae on the Baekdudaegan with intent to prepare the conservational management strategy fur the trail on the ridge of Baekdudaegan. To accomplish the purpose, not only trail condition such as altitude, entire width, bare width, maximum depth and slope of trail, but also deterioration types of trail were surveyed at the total 232 points for 28.4km in length. Furthermore, impact rating class, which could be effective means to check the step and extent of deterioration process, was judged on each points of trail. Putting together these results informs us that the deterioration condition of the trail between Manbokdae and Bokseongijae is not reached the level of grave concern yet, but prompt countermeasure to maintain the existing condition has to be considered with regard for the conditions of location and the increasing amounts of use.

• Korean Journal of Environment and Ecology
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• v.19 no.4
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• pp.385-392
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• 2005

This study was conducted in order to analysis the forest fire effect to the raptors habitating in and around the large forest fire occurred area, Goseong country, Gangwon province, Korea. There were observed raptor birds belonging to 8 species, 3 families, and 2 orders in the survey area. The most dominant species was Eurasian Hobby(Falco subbuteo), which was followed by Common Buzzard(Buteo buteo), Kestrel(Faico tinnunculus) and Chinese Sparrow Hawk(Accipiter soloensis). The largest number of species and individuals were observed in May 2002. In partially undamaged areas and undamaged areas, five species of rapacious birds were observed, which was the largest number of species observed. If an environment where rapacious birds can build nests is created in forest fire damaged area in order to raise the number of species and population, the number of species and population of rapacious birds living in the forest fire damaged area will grow further.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.175-183
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• 2004

They are raising the necessity to prepare the conservational management strategy for the trail on the ridge of the Baekdudaegan where deterioration of natural environment along the trail as the rapid increase of visitors to the Baekdudaegan. The purpose of this study, followed after the Kwon and Lee(2003), is to research the deterioration condition of the trail between Namdeogyusan and Sosagogae on the Baekdudaegan. To accomplish the purpose, not only trail condition such as altitude, entire width, bare width, maximum depth and slope of trail, but also deterioration types of trail were surveyed at the total 182 points for 32.3km in length. Furthermore, impact rating class, which could be effective means to check the step and extent of deterioration process, was judged on each points of trail. Results informs us that the deterioration condition of the trail between Namdeogyusan and Sosagogae is not reached the level of grave concern yet, but some points and sections of trail are in urgent need of the integrated and organized maintenance. And some managerial strategies of trail were proposed in connection with the maintenance for trail on the Baekdudaegan ridge.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.168-179
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• 1993

Use impacts on environmental deteriorations of trail were studied on the three major trails of Sobaeksan National Park in 1992. The entire width and bare width of trail as the trail condition were significantly greater on the more heavily used trail. Maximum depth of trail was not so great in spite of steeper grade of trail in comparison with the other National Parks. Percentages of deepening. rock-exposed. diverged points as the deterioration types of trail which were surveyed at the total of 105 points were high and trail conditions were significantly different from those of non-deteriorated points. On the Ridge trail. the damaged area more severe than Class 4 reaches about 10,335$m^2$ and the deterioration is accelerated. The dominant trees of the the upper layer in trail edge vegetation are changed from Q. mongolica. Aar mono to Q. mongolica for Huibang trail. and from Pinus densiflora. Q. mongolica to P. densiflora and to Q. mongolica for Biro trail as altitude increases. Rhododendron schlippenbachii. Weigelu subsessilis. Salix hulteni. Rubus crataeglfolius were classified for tolerant species and R. coreanus. Vaccinium koreanum for intolerant species to use impacts. Highly competetive species on the Ridge trail were grouped R. schlippenbachii. W. subsessilis. Rubus crataegifolius and Symplocos chinensis for. pilosa.

• Korean Journal of Environment and Ecology
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• v.9 no.2
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• pp.211-220
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• 1996

5 major trails of Odaesan National Park were selected to investigate the use impacts on environmental deterioration of trail accreding to the different amunt of use. The entire width, bare width, maximum depth and slope of trail as the trail comdition surveyed at the total of 120 points were significantly greater on the more heavily-used trail. Major deterioration types of trail were root-exposure, rock-exposure, deepening and divergence in order of frquency and trail conditions of deteriorated points were significantly different from those of non-deteriorated points. The damaged area more severe than Class 4 on trail reached about 379m$^{2}$/km in total, and especcially about 1,196m$^{2}$/km in the section between Chodmyolbogung and Pirobong of Sangwonsa trail. The dominant trees of trail edge vegetation could be Quercus mongolica in upper layer, but in lower layer Rhododecdron schilipenbachii for slope and Actinidia arguta for ridge. Coverage and number of individuals of lower vegetation in trail edge were the lowest on the Sangwonsa trail of the largest use amount, and each trail was dissimilar in species composition of lower layer of edge vegetation.

• Korean Journal of Environment and Ecology
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• v.26 no.6
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• pp.923-933
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• 2012

The purpose of this study targeting Choansan(Mt.) Neighborhood Park in Seoul of South Korea, whose level of visitation and use pressure has been recently increasingly high, was to understand distribution and damage status of forest trail and accordingly, set up direction of how to improve forest trail in urban area. With regards to current damage on forest trail in Choansan(Mt.) Neighborhood Park, the damaged trail with road width of over 2m and with erosion depth of over 30cm amounted to 20.3% and 36.3% respectively. And the trail section with bare land erosion, root exposure or rock exposure and the section whose impact rating class exceeded IV occupied 47.0% and 70.6%, indicating the forest trail was severely damaged. The severely injured trail route mainly included the main forest trail formed along the main ridge, the byroad connected to the main forest trail and the steep forest trail in low-lying area. Based on the study results, five types of restoration of forest trail in Choansan(Mt.) Neighborhood Park were offered, including prevention of forest trail extension, stabilization of forest trail base, maintenance of forest trail surface, vegetation restoration after closing forest trail and maintenance. Ecological restoration was additionally offered. The prevention of forest trail extension was planned to prevent expanded width of forest trail where bare land was exposed. The stabilization of forest trail base was planned to prevent erosion in the forest trail and exposure of roots. The maintenance of forest trail surface was planned in a way to protect the severely damaged forest trail surface by using wood deck and wood stairs and surfacing the road.