• 한국환경생태학회지
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• 제23권4호
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• pp.285-293
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• 2009

본 연구는 초본에 한하여 진행되고 있는 귀화식물 연구 영역을 확대하여 목본 귀화식물인 일본목련을 대상으로 산림군집, 분산범위, 산포방법 등을 조사하였다. 대상지는 경기도 이천시 호법면 매곡리 산 27번지 일대 한국유네스코평화센터 주변 산림지역이다. 일본목련의 분산특성 조사결과 조경 식재된 일본목련이 모수를 중심으로 산림내부까지 확산되었으며, 거리별 분산은 모수로부터 $20{\sim}100m$ 에서 가장 많은 개체수가 관찰되었고 최대 420m 까지 분포하였다. 이러한 일본목련의 분산은 중력산포에 의한 경향이 두드러진 것으로 보이며, 그 밖에 어치, 까마귀, 까치, 청설모, 다람쥐 등의 야생동물에 의한 동물산포가 이루어진 것으로 보인다. 산림군집조사 결과 리기다소나무-일본목련-신갈나무 군집에서는 일본목련이 리기다소나무를 피압 가능한 상태에 있었으며, 신갈나무-일본목련 군집은 중 하층에서 신갈나무와 경쟁 중인 것으로 보인다. 생장량 및 울폐도 분석결과 일본목련은 신갈나무와 졸참나무보다 생장이 빠르며, 내음성 수종으로서 신갈나무, 졸참나무와의 경쟁에서도 뒤지지 않는 것으로 분석되었다. 결과적으로 일본목련은 출현한 군집내 층간우점도, 내음성, 속성수 등의 특징으로 인하여 차후에 산림생태계의 교란을 야기할 것으로 보인다. 특히 본 대상지 산림 내부에서 관찰된 수고 10m, 흉고직경 10cm 이상인 일본목련이 교목층에 분포하고 있는 지역은 일본목련 성목을 대상으로 벌채 등을 통한 관리가 필요한 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제20권5호
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• pp.904-907
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• 2010

The vibration of fungal cultures was evaluated to determine its potential effect on the dispersal of airborne fungal microorganisms suspected of being pathogens. An artificial vibration system, which simulates the actual environmental vibration of fungal structures, was designed and constructed for this purpose. Experiments featured the use of low-frequency vibrations similar to those induced by earthquakes. Within the range of conditions tested, the vibration of fungal cultures was found to affect the airflow-driven generation of bioaerosols.

• 한국식물병리학회지
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• 제14권4호
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• pp.325-330
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• 1998

On the basis of the fact that the pycnidiospore of Botryosphaeria dothidea, the causal fungus of apple white rot is a typical water borne spore, a method for quantitative analysis of pycnidiospore dispersal from the warts produced on the diseased apple tree stem was developed. The warts on which cracks developed either on or around them were cut off at the base, and shaked in the water for 4hours at 2$0^{\circ}C$, in which condition the maximum number of spores were released. The volume of shaking solution was calculated as 1 ml per one wart. At the end of shaking, Trio, a household detergent was added to the shaking solution to the concentration of 0.1%, and shaked for additional 10 minutes at 35$^{\circ}C$ to take off the spores attached on the glass ware. One milliliter of the spore suspension thus prepared were passed through transparent membrane filter (pore size : 3.0 ${\mu}{\textrm}{m}$), and the spores attached on the filter were counted under a microscope ($\times$200) after staining them with lactophenol supplemented with aniline blue. The results thus obtained were statistically consistent when at least 30 warts were used simultaneously in single shaking. This method can be applicable in the elucidation of ecology of sporulation and spore dispersal, and also in the screening of the sporulation inhibitor which can be used in the control of the disease by reducing the inoculum density.

• 한국응용곤충학회지
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• 제40권2호
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• pp.125-129
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• 2001

날개가 없는 몇몇 절지동물들은 공중이동을 하기 위한 수단으로써 이륙행동 보이는 종들이 있다. 본고는 포식성 이리응애류중에서 이륙행동을 보이는 종(Neoseiulus fallacis (Carman)) 과 이륙행동은 보이지 않으나, 공중이동률이 높은 종(Phytoseiulus persimilis Athias-Henriot),이륙행동이 없고 공중이동률이 중간치인 종(N. ca1ifornicus(McGregor))간에 공기역학적 측면에서 어떠한 메커니즘이 작용하는 지에 관한 연구이다. 위 종들의 도보이동 자세와 공주 이동 이륙행동 자세의 몸체의 수직적 위치, 몸체의 크기, 다리의 길이 등의 자료를 가지고 공기역학적 파라미터를 계산한 결과, P. persimilis는 도보이동 자세에서도 N. fallacis가 이륙행동을 보여야만 얻을 수 있는 양의 항력을 얻을 수 있음이 밝혀졌다. 이러한 관점에서 포식성 이리응애류의 이륙행동 진화에 대한 고찰하였다.

• 한국산림과학회지
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• 제95권5호
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• pp.621-627
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• 2006

This study was conducted to understand the pattern and characteristics of seed rain in the broadleaved-Korean pine mixed forest. We established 287 $0.5m^2$ circular seed traps and collected and identified fallen seeds in the traps every two weeks in $150m{\times}150m$ sample plot of the permanent nine hectare of experimental plot in 2005. The overall average density of seed rain was $864.2/m^2$. The seeds of Betula costata Betula costata had the highest number of fallen seeds as $676.0/m^2$ (78.2%), followed by Abies nephrolepis as $57.5/m^2$, B. platyphylla as $37.9/m^2$, Tilia amurensis as $32.2/m^2$, Acer ukurunduense as $17.0/m^2$, A. tegmentosum $14.8/m^2$, and so on. Pinus koraiensis was recorded only $2.5/m^2$ of fallen seeds mainly owing of Korean pine had low rate of purity due to the animal and microbiological predation. Most of seed dispersal have started from the middle to late August and come to an end on the middle of November. The peak time of seed dispersal varied depending on the species. The rate of pure seed by dispersal time varied according to the species, thereupon the aspect of predation and the rate of blasted seed which had influence on the rate of purity also varied according to the species. The density of Korean pine seed rain in the forest gap was significantly different at $P{\leq}0.05$ from in the closed canopy. But the other species had no difference among canopy coverage.

• 한국동물학회지
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• 제21권2호
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• pp.59-66
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• 1978

1974년 8월 포항시에서 표식-방사-재채집 방법에 의한 작은 빨간집 모기 (Culex tritaeniorhynchus)의 비상 분포 및 분포 조사를 실시한 바 그 결과를 요약하면 다음과 같다. 1. 총 23,115개체의 Culex tritaneiorhynchus 암모기에 표식 방사하여 그중 120마리가 재채집되어 0.519%의 재채집율을 나타냈고 조사기간중 채집된 총 57,514마리의 암놈중 0.00208의 표식 모기 양성비를 나타냈다. 2. 방사지점으로 부터의 분산율은 0~2km에서 77.5%, 2~4km에서 11.7%, 4~6km에서 5% 그리고 6~8km에서 5.8%였다. 3. 1일간 최고 비상 거리는 7.5km였다. 1일 평균 분산거리는 1.55km였고, 방사후의 경과일수와 분산 거리와는 연관성은 보이지 않았다.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.137-143
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• 2009

Pre-dispersal seed predation by a granivorous bird, the masked grosbeak (Eophona personata, Fringillidae), was investigated in two bird-dispersed trees, Celtis sinensis and Aphananthe aspera (Ulmaceae). The objectives of this study were to 1) measure direct damage of predation by grosbeaks on plant crops, 2) reveal the temporal pattern of predation within each tree species and its causal factors, and 3) test whether foraging grosbeaks hinder foraging of frugivorous birds, thereby indirectly impacting the reproduction of both tree species. A substantial amount of fruit and seed crop was consumed by grosbeaks (24.3% in Celtis; 55.5% in Aphananthe), and only 17.7% (Celtis) and 16.7% (Aphananthe) were removed by frugivorous birds. At the study site, the grosbeak population size fluctuated greatly during the fruiting seasons of both plant species. As for Celtis, predated seed density also fluctuated temporally, and the local population size of grosbeaks was responsible for predated seed density. In Aphananthe, predation was not fully explained by grosbeak populations or plant phenology, but its peak coincided with that of grosbeak population. These results suggest that predispersal seed predation by granivorous birds can have large negative impacts on the bird-dispersed plants. Changes in local population size of granivorous birds can influence predatation and can affect reproductive success of the bird-dispersed plants available to the birds.

• Journal of Ecology and Environment
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• 제33권1호
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• pp.19-22
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• 2010

Migratory birds, by crossing significant ecological barriers, carry and may subsequently introduce exotic seeds into new ecological zones during period of migration. The study of epizoochory, which includes seed dispersal by adhesion to bird feathers, has been relatively neglected compared to the study of seed dispersal by frugivores. To determine whether exotic seeds are being imported to stopover islands by migrating birds, and to estimate the quantity of seeds of exotic species being introduced, we examined migratory birds that were captured in mist nets for attached exotic plant diaspores in 2008 and 2009 on Hongdo Island, Korea. From a total of 3,947 birds examined, we found exotic seeds of Japanese Chaff Flowers (Achyranthes japonica) attached to three species of migratory birds (0.08%; Eurasian Bittern Botaurus stellaris, Swinhoe's Rail Coturnicops exquisitus and Oriental Turtle Dove Streptopelia orientalis). Despite the low occurrence of A. japonica seeds on the external parts of birds, the results suggest that migratory birds may be potential dispersing agents for A. japonica, a species that is currently threatening native ecosystems on many islands in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.163-169
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• 2003

Studies were conducted on the effect of pruning time, host age, conidial dispersal and weather parameters on the incidence and severity of mulberry leaf spot (Myrothecium roridum). The disease severity (%) increased with increase in shoot age irrespective of pruning date. Maximum disease severity was observed in plants pruned during first week of April and minimum disease severity in plants pruned during first week of March. Significant (P ＜ 0.01) influence of date of pruning, shoot age and their interaction was observed on severity of the disease. Apparent infection rate (r) was significantly higher during the plant growth period from day 48 to day 55. Average apparent yale was higher in plants pruned during first week of April and least in plants pruned during first week of July. The disease infection was negatively correlated to distance from the inoculum source. Leaf spot severity (%) was influenced by weather parameters. Multiple regression analysis revealed contribution of various combinations of weather parameters on the disease severity. Linear prediction model $(Y ＝ －81.803＋1.176x_2＋0.765x_3) with significant $R^2$ was developed for prediction of the disease under natural epiphytotic condition.

• 암석학회지
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• 제22권4호
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• pp.273-289
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• 2013

강하화산재는 농업과 기반시설에 다양한 형태의 피해를 발생시킬 수 있는 악명 높은 재해이며, 특별히 항공과 인체 건강에 가장 유해하다. 본 연구는 백두산 화산으로부터 폭발적 분화에 의하여 화산재가 확산되고 퇴적되는 것을 모델링하기 위한 목적으로 개념적인 모델 설계를 논의하고자 한다. 이는 모델의 가정과 경계 조건에 대한 토의와 더불어 개념적인 모델의 상세 다이어그램, 가능한 입력 파라미터, 단위, 방정식에 대한 논의를 포함한다. 모델에 포함되어 있는 두 가지 주요 과정은 화산재의 확산과 퇴적이며, 만약 모델이 설계되면 모델을 실행시켜 얻을 수 있는 것은 분연주에 포함된 미세 화산재의 총량, 화산재의 이동 거리, 지표면에 침적되는 화산재 두께 등이다.