• 수산해양기술연구
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• 제42권3호
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• pp.158-168
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• 2006

A study on the species composition and seasonal variations of fishery creatures caught by a funnel net was carried out in the coastal water off Dolsan Island, Yeosu from 2002 to 2003. During the study period, a total of 23 fishery creatures species were caught. Seabream(Acanthopagrus schlegeli), sea bass(Lateolabrax japonicus), mullet(Mugil cephalus), puffer(Takifugu niphobles) and rockfish(Sebastes inermis) predominated. These five species accounted for 85.1% of the total number of fishery creatures caught. Seasonal peaks of number of species occurred in summer, while those of number of individuals occurred in autumn. The lowest number of species and individuals were observed in winter. The large annual variation of diversity indices were observed from May to August. These large annual variation of diversity indices were mainly due to predominance of seabream, sea bass and mullet which accounted for most of all fishery creatures caught. The seasonal variations of fishery creatures showed that sea bass and mullet were caught mainly from spring to summer, seabream and puffer were caught mainly in autumn, and rockfish and brotula(Hoplobrotula armata) were caught mainly in winter.

• 수산해양교육연구
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• 제17권1호
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• pp.132-143
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• 2005

In order to investigate the seasonal variation of watermass and fishery creatures in the adjacent sea of Naro Island, an oceanographic observation was carried out seasonally on the fishing grounds, and the sales performance data of the fisheries cooperative's joint market of Naro Island was examined by using a principal component analysis. The temperature and salinity ranged from 8.1 $^{\circ}C$ to 13.7 $^{\circ}C$ and from 33.1 psu to 34.3 psu in spring, from 14.5 $^{\circ}C$ to 24.2 $^{\circ}C$ and from 30.5 psu to 34.1 psu in summer, from 14.8 $^{\circ}C$ to 18.6 $^{\circ}C$ and from 30.1 psu to 34.0 psu in autumn, and from 4.3 $^{\circ}C$ to 10.1 $^{\circ}C$ and from 33.1 psu to 34.9 psu in winter, respectively. In winter and spring, the offshore water spread out to all sea areas of all water layers. In summer, the mixed waters covered the entire sea surface whereas the mixed water and offshore water covered the bottom. In autumn, the coastal water and mixed water appeared on the surface, but the mixed water was distributed widely on the bottom and the offshore water began to appear in the open sea. For two years from 2002 to 2003, 58 fishery creature species in total were sold in the fisheries cooperative's joint market of Naro Island. In general, the total of 50% fish were sold, and crustacea and mollusc by each 25%. Medium shrimp, whiparm octopus, blue crab, and octopus predominated. A number of species and biomass of fishery creatures were sold mostly in April and May, while they were sold the least in January and February. The seasonal sales results showed that mullet, angler, short necked clam, large shrimp, and webfoot octopus were sold mainly in spring, tonguefish, flathead, pomfret, glass eel, blue crab, whiparm octopus, and squid were sold mainly in summer, and octopus, medium shrimp, and spanish mackerel were sold mainly in autumn.

• 한국환경과학회지
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• 제16권6호
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• pp.745-750
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• 2007

Large scale of loess has been applied on the south - sea shore of the Korean peninsula to treat red tides, due to many fishery's devastation by red tides every year. However, coastal ecosystem is ruined by the huge amount of loess applied every year. Almost all creatures, living under water such as sea weeds, clams, and fishes, where loess was applied, are disappearing. In this paper, alternative methods of the loess application are investigated. The amount of loess could be reduced by the alternative methods, Especially, loess mixed with calcium oxide has excellent effects to reduce Cochlodinium polykrikoides numbers. It was found that when loess is used with calcium oxide(CaO), removal efficiency of red tides is highly increased. Moreover, the amount of loess could be reduced dramatically.

• 대한원격탐사학회지
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• 제39권5_3호
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• pp.909-919
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• 2023

Benthic marine invertebrates, the invertebrates living on the bottom of the ocean, are an essential component of the marine ecosystem, but excessive reproduction of invertebrate grazers or pirate creatures can cause damage to the coastal fishery ecosystem. In this study, we compared and evaluated You Only Look Once Version 7 (YOLOv7), the most widely used deep learning model for real-time object detection, and detection tansformer (DETR), a transformer-based model, using underwater images for benthic marine invertebratesin the coasts of South Korea. YOLOv7 showed a mean average precision at 0.5 (mAP@0.5) of 0.899, and DETR showed an mAP@0.5 of 0.862, which implies that YOLOv7 is more appropriate for object detection of various sizes. This is because YOLOv7 generates the bounding boxes at multiple scales that can help detect small objects. Both models had a processing speed of more than 30 frames persecond (FPS),so it is expected that real-time object detection from the images provided by divers and underwater drones will be possible. The proposed method can be used to prevent and restore damage to coastal fisheries ecosystems, such as rescuing invertebrate grazers and creating sea forests to prevent ocean desertification.

• 한국습지학회지
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• 제9권1호
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• pp.107-114
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• 2007

This study aimed to investigate the hexachlorobenzene (HCB) dechlorinating ability of sediment microbes collected from a natural canal receiving secondary effluents from an industrial estate and nearby factories. Nine sites along the stream and one in the estuary in the Gulf of Thailand into which the canal spills were specified and sampling for sediment and water. Preliminary analysis of the sediments showed that the first four sites nearest to the discharging location were contaminated by HCB within the range of 0.18 to 1.25 ppm. Apart from that, 1,3,5-trichlorobenzene which has never been commercially produced or used in any manufacturing processes except for the transformation from higher chlorinated benzene was also identified in the range of 0.16 to 0.24 ppm. This suggested a possibility of sporadically HCB contamination in this stream. Of more important, people in the community along this canal earn their living by coastal fishery; hence, posing a risk of spreading HCB and its less chlorinated congeners via food chain from caught marine creatures to human. As a result, there is an urgent need to understand the behavior of HCB dechlorination in this stream sediment which can lead to a clean-up action in the future. Serum bottles with sediment slurries (sediment to water ratio of 1:1 (v/v) and filtered to remove particles larger than 0.7 mm) from each site were inoculated with 2 mg/l of HCB, kept anaerobically in the dark at room temperature without any nourishment, and analyzed for HCB and its less-chlorinated congeners every 6 days. Total chemical oxygen demand, suspended solids, and volatile suspended solids were in the range of 21,492-73,584, 158,100-518,100 and 6,000-32,700 mg/l, respectively. It was found that all sediment slurries began to dechlorinate HCB in 12 to 30 days and the HCB was completely removed within 42 to 60 days or so. On the other hand, there was no HCB dechlorination occurred in the controlled set which was sterilized by autoclaving prior to the addition of HCB. This implies that the HCB transformation was solely due to microorganisms' activities. HCB was dechlorinated principally via pentachlolobenzene to 1,2,3,5-tetrachlorobenzene and terminated at 1,3,5-trichlorobenzene which is the major pathway as reported by many researchers. Dichlorobenzene has not been detected in any samples within the dechlorination period of 60 days. The results indicate that the microbial matrix in the sediment of this stream has an outstanding capability to dechlorinate HCB. Existing substrates and nutrients which mainly sorbed onto the solid phase and the typical temperature in Thailand were sufficient and suitable to promote the activities of these HCB-dechlorinating microbes.

• 헤리티지:역사와 과학
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• 제47권4호
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• pp.178-191
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• 2014

진상제는 지방의 특산물을 왕실에 봉진하는 제도이다. 진상물은 물품의 성격, 봉진시기, 용도에 따라 제향진상, 방물진상, 물선진상, 약재진상으로 구분된다. 이 중에서 물선진상은 전국의 산해진미를 봉진하는 것으로, 주로 식재료로 구성되었다. 그리고 물선진상은 다른 진상물과 달리 물품의 수량 경감 내지 일시적인 봉진 중지가 빈번하였다. 이는 물선진상의 경감을 통해 백성에게 물질적인 혜택을 줌으로써 자애로운 군주상을 확보하기 위한 국왕의 의도였다. 숙종 역시 재위기간 동안 빈번히 물선진상을 경감하거나 폐지하였다. 그러나 이 같은 물선진상 변경내역의 문서 보완이 미비하면서, 영조 즉위 직후 물선진상의 물종 및 수량이 불분명한 상태였다. 이에 영조는 "진상별단등록" 간행을 통해 물선진상의 물종 및 수량, 경감내역을 분명히 하였다. "진상별단등록"은 진상지역, 봉진시기, 봉진대상, 물종 및 수량, 경감내역이 기재되어 있다. 이 중에서 물선진상의 물종 및 수량은 다른 내용에 비해 중요하다. "진상별단등록"에 수록된 물선진상은 총 176종에 이르는데, 이 중에서 어류, 패류, 건어류 등 수산물이 117종으로 약 67%를 차지하고 있었다. 그리고 대부분의 물선진상이 원재료로 구성되어 있었고, 생물 이외에 말리거나 절이는 등 다양한 형태로 가공되었다. 물선진상의 지역별 분정특징을 살펴보면, 경상도, 함경도, 강원도 순으로 물선진상이 많이 수록되어 있다. 그리고 이들 지역은 동해안과 접해 있다보니, 수산물의 비중이 상대적으로 높은 편이다. 경상도와 전라도는 석류, 유자 등 양남지역의 대표적인 과실류가 분정되어 있었고, 제주도는 감귤류, 각종 전복가공품 등 전국에서 유일하게 분정된 물종이 대부분을 차지하고 있었다. 그리고 서울과 지리적으로 먼 곳에 위치한 도에는 건어류, 염어류 등을 집중적으로 분정하였다.