한국연안 해조류 생물량의 연간 변동 양상: 전북 외조도와 주삼도 지역

최한길,이기훈,만효금,유현일,박향하,김정하,정익교,Choi, Han-Gil,Lee, Ki-Hun,Wan, Xiao Qin,Yoo, Hyun-Il,Park, Hyang-Ha,Kim, Jeong-Ha,Chung, Ik-Kyo 한국조류학회(藻類) 2008 ALGAE Vol.23 No.4

Seasonal and vertical variations of seaweed biomass were examined at Woejodo and Jusamdo of western sea, Korea from July 2006 to April 2007. Annual seaweed biomass was 198.27 g m$^{-2}$ in wet weight at Woejodo and 417.34 g m$^{-2}$ at Jusamdo, respectively and biomass of intertidal zone was greater than that of subtidal zone at Jusamdo sites. Seaweeds distributed vertically from mid intertidal to 5 m of subtidal zone at Woejodo and from high intertidal to 10m of subtidal zone at Jusamdo. Seaweed biomass and species number were maximal at lower intertidal zone (27 species, 365.43 g m$^{-2}$) of Woejodo and at mid intertidal zone (26 species, 684.18 g m$^{-2}$) of Jusamdo. Seasonal biomass varied from 136.73g m$^{-2}$ in autumn to 249.33 g m$^{-2}$ in winter at Woejodo and from 353.37 g m$^{-2}$ in autumn to 482.07 g m$^{-2}$ in summer at Jusamdo. Dominant species was Sargassum thunbergii showing highest annual biomass (Woejodo, 94.68 g m$^{-2}$ Jusamdo, 228.59 g m$^{-2}$) among all seaweeds and finding at various shore levels during the study period. Subdominant species were Corallina pilulifera and Gracilaria textorii at Woejodo, and were Sargassum fusiformis and Chondria crassicaulis at Jusamdo. Thus, we can conclude that Jusamdo shore is better place than Woejodo based on seaweed biomass and vertical distribution, and S. thunbergii is the representative species of the two islands.

Phenology of Host Chondrus ocellatus with Filamentous Green Endophyte Infection

최한길,김창송,김영식,이순정,박명애,남기완 한국해양과학기술원 2015 Ocean science journal Vol.50 No.3

Monthly variations in gametophyte and tetrasporophyte biomass of Chondrus ocellatus Holmes, a commercial carragenophyte alga, were examined at wave-exposed and sheltered shore stations of Jungdori, Wando, Korea from September, 2013 to August, 2014. The frequency of infection of the fronds with a green filamentous endophyte was investigated and the endophyte was identified using tufA analysis. Biomass of C. ocellatus was significantly greater at the exposed shore (331.84 g wet wt. m-2) than at the sheltered shore (181 g wet wt. m-2); the average biomass was 259 g wet wt. m-2. Gametophyte biomass of C. ocellatus accounted for 64.25% of the total biomass (259 g wet wt. m-2); tetrasporophyte biomass was 93.05 g wet wt. m-2 (35.93%). Biomass was minimal in winter and maximal in summer at both stations and similar patterns were found for gametophyte and tetrasporophyte biomass. Frond lengths and weights of C. ocellatus were slightly greater at the exposed shore than at the sheltered shore. Fronds of C. ocellatus were infected by a green endophytic species, which grew in between the cortical and medullar tissue and was identified as Ulvella ramosa by tufA analysis. We conclude that the optimal harvesting period of the C. ocellatus field population in terms of biomass might be autumn, after the rapid growth period. Additional in-depth research on the endophytes, such as infection mechanism and frequency, should be performed in order to maintain and manage the field populations of C. ocellatus.

가열 아스팔트 혼합물의 강도특성 평가를 위한 시험방법 연구

최한길,유진명,조규태,남영국 한국도로학회 2001 한국도로학회 학술대회 발표논문 초록집 Vol.2001 No.10

Effects of wave action and grazers on frond perforation of the green alga, Ulva australis

최한길,김보연,박세경,Jin Suk Heo,Changsong Kim,김영식,Ki Wan Nam 한국조류학회I 2015 ALGAE Vol.30 No.1

The growth and hole formation of Ulva australis were examined at seven coastal areas of Korea between July and August, 2013. Animal species and weight growing on the Ulva fronds were estimated at Haseom, Pohang, and Woedo. The effects of wave exposure on the morphological features and residential animals of Ulva fronds were investigated at wave-exposed and sheltered sites of Seongsan on October 19, 2013. U. australis had different frond areas (82-665 cm2), hole areas (2.5-6.3 cm2), and hole numbers (9.8-41.3 holes) at the seven sites. Within 0.1 m2 of Ulva frond, hole areas ranged from 0.37 to 5.94 cm2, and between 4.9 and 36.2 holes were observed. Fourteen residential animal species were observed at the three evaluated sites, 75.0 (Haseom) to 408.7 individuals 100 g-1 Ulva (Pohang) per site. The dominant residential species at each site differed with Amphithoe sp. at Haseom, Monodonta spp. at Pohang, and Pagurus sp. at Woedo. The growth (frond area, wet weight) and hole number of Ulva fronds, and the number of residential animals were significantly greater in samples collected from the sheltered shore than the wave-exposed shore of Seongsan. The present results showed U. australis grew well at sheltered shores and had more holes on the fronds due to abundance of residential animals. The dominant residential animals (crabs, gammaridea, and snails) were similar in the Ulva populations of sheltered and wave-exposed shores, but greater species diversity was observed at the exposed shore (18 species ver. 11 species). In conclusion, U. australis is a keystone species providing habitat to various invertebrates and frond holes are positively correlated to the number of residential animals.

홍조류 꼬시래기(Agarophyton vermiculophyllum)의 과포자방출 유도 방법에 대한 연구

최한길 한국해양과학기술원 2020 Ocean and Polar Research Vol.42 No.3

The aim of this study was to examine optimal induction method for carpospore release from Agarophyton vermiculophyllum cystocarps for seedling production. We tested the effects of environmental factors on carpospore release by using five different induction methods; spontaneous, desiccation, low temperature, desiccation+low temperature, and osmotic shock. Also, carpospores release was estimated at three temperatures (20, 25, and 30℃), and then under combinations of three day lengths (8, 12, and 16h) and two irradiances (30 and 60 µmol photons m-2 s-1), after pretreatment at desiccation+low temperature for 2 hr. The number of carpospores released was between 113 ~ 682 spores /cystocarp/day and it was maximal in the desiccation+low temperature treatment. Optimal environmental conditions for carpospore release of A. vermiculophyllum were 25℃, 16 h, and 60 µmol photons m-2 s-1. The present results suggest that massive carpospores for seedling production of A. vermiculophyllum could be obtained under a combination of 25℃, 16 h, and 60 µmol photons m-2 s-1 after pretreatment in the desiccation+low temperature.

Structure of Intertidal Macroalgal Community at the Yeonpyeongdo Islets, Korea

최한길,유현일,송홍인 한국수산과학회 2008 Fisheries and Aquatic Sciences Vol.11 No.3

Intertidal benthic algal communities on the shores of Gujido and Daeyeonpyeongdo islets, Korea, were examined in October 2007. At both sites, 45 seaweeds including 7 green, 6 brown and 32 red algae were identified. The number of species at Gujido (38 species) was 1.5 times higher than at Daeyeonpyeongdo (25 species), but seaweed coverage was very similar with about 20%. Dominant seaweeds in terms of coverage and importance value were Hildenbrandtia sp., Caulacanthus okamurae, Ulva pertusa, and Gelidium amansii at Gujido and U. pertusa, Hildenbrandtia sp., Gelidium divaricatum at Daeyeonpyeongdo. The vertical distribution pattern of the seaweeds was G. divaricatum - U. pertusa, Hildenbrandtia sp. - U. pertusa, Hildenbrandtia sp., Ishige okamurae from upper to lower intertidal zone but seaweed zonations were not observed on the Gujido rocky shore. At both sites, coarsely-branched forms were the dominant functional group in species number and percent cover (among benthic algal species). The rocky shores of the two sites were dominated by crustose coralline and green algae, whose presence generally results in decreased seaweed biodiversity and community stability. Therefore, the shores of the Yeonpyeongdo islets are of considerable environmental concern and should be monitored for seaweed species composition and community structure.

월성원자력발전소 온배수가 해조류 종조성 및 군집구조에 미치는 영향

최한길,Choi, Han-Gil 한국조류학회(藻類) 2008 ALGAE Vol.23 No.2

Marine algal flora and community structure were seasonally examined at three sites in the vicinity of the Wolseong nuclear power plant in Korea from February to November 2006. A total of 126 seaweeds including 25 green, 31 brown, 70 red algae, and 1 marine plant were identified. The greatest number of species occurred at Jeonchonri (101 species) followed by intake (88 species) and discharge (29 species) during the study period. Of 126 seaweeds, 76 annuals and 13 warm tolerance species were recorded. Dominant species based on important value (IV > 10) were Ulva pertusa and Enteromorpha linza at intake, U. pertusa and Padina arborescens at discharge, and Sargassum horneri and Corallina pilulifera at Jeonchonri shore. Annual average biomass exhibited a wide range of variations, from 40.67g m-2 in dry weight at discharge to 133.69g m-2 at Jeonchonri. Among six functional groups, dominant group was coarsely-branched form at intake and Jeonchonri, but it was different at discharge site as filamentous form. Seaweed community structures of discharge site were distinguishable in decreasing species richness, biomass, species diversity index (H’), richness index (R), and evenness index (J’). Also, the ratios of green algae, warm tolerance species, annual algae, filamentous form and dominance index (DI) remarkably increased. Such phenomenons of discharge site are usually found under environmentally stressful conditions such as high disturbance. Thus, I can conclude that the heated effluents of nuclear power plant act as environmental stress influencing seaweed community structures and it can be detected with various community indices.

쿠웨이트 都市高速道路 現場의 補强土 및 土工施工事例

崔澣吉(최한길) 대한토목학회 1988 대한토목학회지 Vol.36 No.1

학술발표회 : 7) 해양생물분야 , 포스터발표 ; Interrelation with food and habitat preference of Littorina in upper intertidal tide pools

최한길(Han Gil Choi),김영식(Young Sik Kim),남기완(Ki Wan Nam) 한국국제경제학회 2001 춘계 수산관련학회 공동학술대회발표 요지집 Vol.0 No.-

SIFT 특징점 정합과 필터 기반 확장성을 이용한 기하학적 왜곡에 강인한 영상 정합

최한길(Hangill Choi),류승철(Seungchul Ryu),김승룡(Seungryong Kim),박기홍(Kihong Park),손광훈(Kwanghoon Sohn) 대한전자공학회 2015 대한전자공학회 학술대회 Vol.2015 No.6

This paper introduces efficient dense correspondence approach to estimate matching for images as varying photometric and geometric variations, such as tone, scale and rotation. Our approach employs filter-based propagation technique. To estimate reliable scale and rotation on overall image domain, we assume that similar pixels of same object have similar scale and rotation values. We propagate sparse scales and rotations with detected feature points by the edge-aware filtering technique. Finally, we find dense correspondence field by using belief propagation and coarse-to-fine scheme. Our method shows outperforming results compared to conventional dense matching algorithms, such as SIFT flow, DAISY, and Scale-Less SIFT.