• Title/Summary/Keyword: D. pygmy

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Drumming bioacoustics of woodpeckers in South Korea (한국에 서식하는 딱다구리목 드러밍의 생물음향학적 특성 연구)

  • Ki, Kyong-Seok;Hong, Suk-Hwan;Gim, Ji-Yeun
    • Korean Journal of Environment and Ecology
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    • v.28 no.4
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    • pp.404-410
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    • 2014
  • In this study, we conducted an analysis of the drumming bioacoustics of three woodpeckers typical to South Korea. The targeted species were, from largest to smallest in size, the Black Woodpecker(Dryocopus martius), the Great Spotted Woodpecker(Dendrocopos major) and the Japanese Pygmy Woodpecker(Dendrocopos Kizuki). The drumming sounds of these three species of woodpeckers were recorded and analyzed. Sound recordings were taken in the Guryongsa Valley, Chiaksan National Park and on the campus of Sangji University, Wonju City, South Korea. Drumming recordings were obtained in the following manner. As researchers walked along trails in the investigation areas, when woodpecker drumming sounds were indicated, positive identification of the species was made using binoculars then the recording of the drumming sound was started. The average time per drumming, in seconds, was Black Woodpecker(D. martius) 1.614 seconds, Great Spotted Woodpecker(D. major) 0.683 seconds and Japanese Pygmy woodpecker(D. Kizuki) 0.200 seconds. The average number of strikes for each drumming was Black Woodpecker(D. martius) 31.2 times, Great Spotted Woodpecker(D. major) 14.9 times and Japanese Pygmy Woodpecker(D. Kizuki) 6.7 times. The strike speed, in strikes/sec, for each species was the Black Woodpecker(D. martius)19.3strikes/sec, the Great Spotted Woodpecker(D. major) 21.8strikes/sec and Japanese Pygmy Woodpecker(D. Kizuki)33.3strikes/sec. The frequency of drumming, in Hertz, was Black Woodpecker(D. martius) 776.9Hz, Great Spotted Woodpecker (D. major) 1,213.8Hz and Japanese Pygmy Woodpecker(D. Kizuki) 826.0Hz. In interpreting this data, Analysis of Variance (ANOVA) was used and it was determined that there was a significant statistical difference between species in drumming duration, time and interval of striking. The findings support that the bigger the biomass of the woodpecker, the longer the drumming duration and striking time. However, the smaller the size of the woodpecker, the faster the strike speed. A correlation between body type size and drumming characteristics was clearly identified. As for strike frequency, measured in Hertz, the medium sized Great Spotted Woodpecker's (D. major) frequency was high whereas the Black Woodpecker(D. martius) and Japanese Pygmy Woodpecker's(D. Kizuki) frequency was similar. A clear trend in reference to body size on this measure does not exist.

Comparative study on experimental measurements of discharge using various flow meters (유속측정 기기별 측정성과에 대한 실험적 비교분석)

  • Lee, Jae-Hyug;Kang, Kyang-Min;Jung, Sung-Won;Kim, Tae-Woong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1908-1912
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    • 2009
  • 유량자료는 물의 순환과정을 규명하고 효율적인 수자원 개발 및 이수 치수 계획 등에 매우 귀중하게 이용된다. 그러나 이러한 유량자료를 확보하는 데는 많은 시간과 경비 등이 요구되기 때문에 주요 수위의 유량측정자료로 수위-유량관계 곡선식(Stage-Discharge Curve)을 개발하여 유량자료를 환산하고 있다. 따라서 수위-유량관계 곡선식의 신뢰도는 유량자료의 품질에 절대적인 영향을 미치는 요인으로 작용된다. 수문학을 연구하는 많은 학자들은 고품질의 유량자료를 생산하여 신뢰성 있는 곡선식을 개발하고자 유량측정 방법과 기준, 장비개량 등에 관한 연구를 수행하고 있다. 측정하고자 하는 기기별 측정 성과에 대한 연구 자료가 거의 없이 국내에 보급된 다양한 유속측정기기를 사용하여 유량자료를 생산하여 활용하고 있다. 본 연구에서는 규격화된 콘크리트 수로에 일정한 유량을 흘려보내고 다양한 측정기기를 이용하여 유속을 측정하였다. 그리고 이 측정성과를 이용하여 유량을 산정하고 비교분석하였다. 실험을 위해서 국내에서 일반적으로 사용되고 있는 측정기기로 마그네틱유속계(Electromagnetic Current Meter), 휴대용유량계(Flow Meter), 프라이스유속계(USGS Type AA Current Meter), 갈수기용유속계(USGS Pygmy Meter)등의 장비를 사용하였으며, 동일한 조건에서 유량을 얻음으로 측정 기기가 제시하는 유량을 알 수 있었다. 비교검토에 적용하고자 측정한 수심으로는 0.25m, 0.30m, 0.35m, 0.40m의 4개 Case로 진행이 되었으며, 측정방법으로는 도섭법(Wading Measurement)에 의하거나 케이블웨이(Cableway), 교량법(Bridge Measurement), 보트법(Boat Measurement)등이 있으나, 신뢰성과 정확도를 높이기 위해 도섭법으로 수면에서 0.6d 지점의 유량측정방법(1점법)을 적용하였다. USGS Type AA Current Meter, USGS Pygmy Meter는 유속측정기기의 검교정을 받았으므로 다른 실험유속측정치의 비교를 위한 기준값으로 사용하였다. 따라서 국내에서 널리 사용되는 측정기기(Electromagnetic Current meter, Flow Meter, USGS Type AA Current Meter, USGS Pygmy Meter)별 검토 결과 프라이스유속계를 기준으로 마그네틱유속계는 ${\pm}$10% 이상, 갈수기용 유속계 및 휴대용 유량계는 ${\pm}$5% 미만의 차이가 있음을 확인할 수 있었다.

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Development of the Glandular Trichomes in Trapping Leaves of Drosera Species (끈끈이주걱속 점착식 포충엽의 분비모 발달)

  • Lee, Hye-Jin;Kim, In-Sun
    • Applied Microscopy
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    • v.39 no.1
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    • pp.57-64
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    • 2009
  • The trapping leaves of Drosera capture insects by secreting sticky mucilage from numerous glandular trichomes (GTs) that are developed on the leaf epidermis. The present study examines and compares the structural features of those trichomes in Drosera binata and D. pygmy with the use of light and electron microscopy. The study focuses primarily on the development and differentiation pattern of the GTs during growth. Upon examination, the upper and lower epidermis were readily distinguishable by the features of GTs in developing leaves. In particular, the GTs were dense in the upper epidermis and along the leaf margin. In D. binata, the capitate GTs with elongated stalk and sessile peltate GTs were found most commonly, whereas only capitate GTs with varying degrees of the stalk length were observed in D. pygmy. Up to ca. $2.2{\sim}3.4\;mm$ long capitate GTs were seen in the leaf margins of D. binata and ca. $3.7{\sim}4.2\;mm$ long GTs having racket-like head with adaxial hemispheric structures, otherwise known as tentacles, were noted in the leaf margin of D. pygmy. The peltate GTs were found to be distributed in the lower epidermis of D. binata. In both species, head cells were dense with cytoplasm containing high numbers of Golgi bodies, ER, mitochondria and small vesicles. Secretory materials accumulated within numerous small vacuoles, then fused together to form a single large vacuole, which serves as a secretory cavity. Flection movement of the marginal GTs and leaf blade GTs, and increased mucilage secretion from the head cells upon contact with prey during the capturing process are considered to be major factors in their active insectivorous mechanism. The findings of this study will be useful in comparisons to similar findings in other species that form adhesive trapping leaves, such as Drosophyllum or Pinguicula., further contributing a better understanding of the function and structure of the trapping leaves of carnivorous plants.