To analyse and review the fishing performance and species composition according to the size of the entrance and mesh of the pot in the southern coastal waters (Tongyeong, Gyeongsangnam-do and Yeosu, Jeollanam-do), the experiment in this study caught one class, eight orders, 17 families, 23 species, 662 fishes, and 99,833 g. The largest number of fish species was Conger myriaster (301 fishes caught) accounting for 45.5%, followed by Octopus vulgaris (152) accounting for 23.0%, Charybdis japonica (45) accounting for 6.8%, Sebastiscus marmoratus (43) accounting for 6.5%, and Parapercis sexfasciata (42) accounting for 6.3%. Conger myriaster, Octopus vulgaris, Charybdis japonica, Sebastiscus marmoratus, and Parapercis sexfasciata accounted for 88.1% of the total catch. For other fish species, 68 fishes of 18 species were caught, accounting for 12.5% of the total. As a result of the total catch survey, the catch rate of Conger myriaster was the highest at 50.9% in B. 22 mm/280 mm. In addition, the average total length per fish increased as the entrance size increased. The weight ratios of Conger myriaster, Octopus vulgaris, and other fish species based on the total weight caught in each pots of the six species of test fishing gear are as follows. A pots 66.6%, 26.5%, 6.9%, B pots 57.2%, 24.5 %, 18.3%, C pots 43.2%, 31.5%, 25.3%, D pots 7.4%, 56.7%, 35.9%, E pots 43.6%, 0%, 56.4%, and F pots 5.0%, 79.6%, 15.4%.
This study was conducted to evaluate the performance of the octopus pot according to mesh sizes. Entering behavior of Octopus minor and bait (Macrophthalmus japonicus) escape rate on the mesh sizes of the pots were investigated for six times in indoor tank. The sea trials for evaluating the performance of Octopus minor pot to different mesh sizes (22, 20 and 18 mm) were conducted for six times from 2017 to 2018 in the coastal sea of Deukyang Bay, the Republic of Korea. Behavior patterns of contact pot to leaved pot were more frequent than contact pot to bait search. When the octopus contacted to the pot, there was no clear search behavior to distinguish the mesh sizes. Total catch of 46% was accounted for 18 mm pots, followed by 34% at 20 mm and 20% at 22 mm (P < 0.05). Catch per unit effort was calculated as 30 g/pot at 22 mm, 44 g/pot at 20 mm and 59 g/pot at 18 mm. As a result of evaluating 50% selection of mantle length and weight on the mesh sizes, mantle length (mm) and weight (g) were 84.6 and 147.8 in 22 mm, followed by 20 and 18 mm.
This study was conducted to analyze fishing capacity and bycatch by mesh size and entrance size of spring net pot conductedby water tank and field experiment. The water tank experiments were conducted by using traps with mesh size of 22 mm and entrance size of 120 mm and 140 mm, respectively in the water tank of NIFS. The field experiment was conducted using 5 kinds of spring net pot with mesh sizes of 20 mm, 22 mm, 35 mm and entrance size of 120 mm, 130 mm, 140 mm, 360 mm by coastal trap fishery vessel operating around the area of Geoje island. In the result of water tank experiments, the catch of conger eel was 1.5 times higher when using trap with entrance size of 140 mm than that of 120 mm. In the field experiment, when using same mesh size, the larger the entrance size, the higher amount of conger eel catch, bycatch and number of bycatch species. When using the same entrance size, the larger the mesh size, the lower amount of conger eel catch and number of bycatch species, whereas the amount of bycatch showed increasing trend.
Morotoge shrimp Pandalopsis japonica is caught by pot and others in the eastern coastal waters of Korea. Comparative fishing experiments were carried out in the eastern coast of Korea, using the dome–shaped pots with different five mesh sizes (17.1, 24.8, 35.3, 39.8, and 48.3 mm) in order to estimate the mesh selectivity of the pot for the morotoge shrimp, Pandalopsis japonica. The SELECT (Share Each Length’s Catch Total) analysis method was applied to the catch data. The master selection curve of the pot for the shrimp was estimated to be s(R) = exp(15.770R–10.573)/[1+exp(15.770R–10.753)], where R is the ratio of carapace length to mesh size. From the selection curves, the carapace lengths of 50% retention were 11.6, 17.0, 23.9, and 34.1 mm for 17, 25, 35, and 50 mm mesh–size pot, respectively. It means that the pots of larger mesh size allow more shrimp of small size to escape.
분화용 나팔나리의 구근 크기, 저온처리 및 입실 시기 에 따른 개화 반응을 연구하였다. 국내 육성 분화용 나 팔나리 ‘White Eve’와 ‘White LoSong’의 구근을 대상으 로 구근의 크기가 18~20cm 일 때 화수가 3개 이상이며 초장은 30cm 정도 였으며, 개화소요일 수는 138일 내외 로 소요되었다. 한편 국내 육성 분화용 나팔나리 ‘Charm’ 의 저온처리에 따른 개화용 구근의 휴면타파 시험 결과, 2주간 15oC에서 예냉 후에 6주간 4oC에서 저온 처리 후 15oC 온실에 정식하면 개화율이 100%였고, 정식 후 개 화소요일은 135일이었고, 개화수는 6개 이상으로 양호하 였으며, 초장도 30cm 이하로 상업적 분화용으로 적절하 였다. 분화용 나팔나리 ‘White Eve’를 대상으로 11월 15일, 12월 1일과 12월 15일의 정식시기에 따른 개화시 기는 야간 처리온도가 15oC일 경우 10oC보다 10 ~ 20일 정도 빨랐고, 정식시기가 늦을 수록 개화시기가 빨라서 15oC에 12월 15일 정식은 115일이 소요되어 4월 초에 개화되었다. 나팔나리 구근의 크기 18 ~ 20cm를 2주간 15oC에서 예냉 후에 6주간 4oC에서 저온처리 후 15oC 온실에 정식하면 우수한 분화 생산이 가능하다.
국내 육성 분화용 나팔나리 일대 잡종 ‘Charm’의 자구를 개화용 구근으로 비대시키기 위한 가장 효율적인 구의 크기, 식재 간격, 깊이 및 시기를 조사하였다. 자구의크기가 2cm에서 8cm를 식재한 후 수확한 구는 8cm에서구의 둘레가 16cm 이상이었고, 개화 구근(구 둘레 15cm이상)의 비율이 62.5%로 가장 높았다. 구의 둘레가 6cm인 자구를 간격 7.5×7.5cm 이상으로 식재하였을 때, 구근의 둘레가 14.7~15.2cm이고, 무게는 28.2~30.8g이었으며, MFB(marketable flowering bulb) 비율은 48.0~49.8%로 유의 차이가 없었으나 구근의 생산 수량을 감안하면7.5×7.5cm가 가장 이상적이다. 소구의 식재 깊이는 맹아율과 분구율, 구의 둘레를 고려하여 보았을 때, 깊이3~5cm의 식재가 가장 바람직하다. 노지에서 상자에 식재한 소구는 동절기에 모두 동사하였고, 포장에 식재한 소구는 맹아율 17.8%이었으나 무가온 온실에서 상자에 식재한 것은 90.5%이었다. 노지 식재에서 무피복의 맹아율은 0%, 비닐 피복은 13.4%, 짚 피복은 29.6%로 나타났다. 소구의 크기가 4cm를 10월 10일, 10월 27일과11월 10일에 무가온 온실에 식재하였을 때 맹아율은 모두 90% 이상이었으나, 일찍 심을수록 구의 무게가 커서10월 10일 식재인 경우 구 둘레가 13cm가 되었다. 따라서분화용 나팔나리는 구 둘레가 8cm 정도인 자구를 10월 초에 간격 7.5×7.5cm, 깊이 5cm로 식재하여 이듬해 9월에 굴취하면 충분히 구 비대가 되어 개화용 구근으로 이용할 수 있다.
Fishing experiments were carried out in the adjacent sea of Yeongil Bay, the eastern cost of Korea from 2003 to 2004 using the dome-shaped pots with different five mesh sizes (17.1, 24.8, 35.3, 39.8, and 48.3mm) in order to determine the size selectivity of pots for the whelk, Buccinum opisthoplectum. The catch species were composed of Buccinum opisthoplectum (45.4%), Buccinum striatissimum (30.1%), Pandalopsis japonica (9.3%), Chionoecetes opilio (8.9%), and so on. The shell height (l) of Buccinum opisthoplectum caught in the experimental fishing pots was measured. The SELECT (Share Each Length's Catch Total) analysis method was applied with fishing data to obtain master selection curve. The model with the estimated split parameter was found to fit the catch data best. The master selection curve was estimated to be s (R)〓exp (7.833R-10.871)/[1 + exp (7.833R-10.871], where R is the ratio of shell height to mesh size. The relative shell length for 50% retention was 1.388, and the selection range was 0.281. It means that the pots of larger mesh size allow more whelks of small size to escape.
This paper presents the mesh selectivity of a net pot for common octopus Octopus minor for the sustainable resources management of common octopus. The filed experiments were carried out the total 10 times in the southern part of coastal sea in Korea from March to May in 2010 using net pots of five different mesh sizes (16, 18, 20, 22 and 26mm). The test of size selectivity, indicated a 50% selection value on the logistic master curve of 3.195, whereby 50% of individuals with a mantle size of approximately 70.3mm selected a mesh size of 22mm. Considering that 50% of common octopus entering sexual maturity have a mantle size of 70.6mm, the optimum mesh size should be equal to, or larger than 22mm.
For the optimal design of a shrimp pot to control the catch size and to reduce catch the small size shrimp, tank experiments were carried out to study the pot stability under water. Tank experiments were carried out to measure the drag with 4 kinds of model pots that have 50% selection on the individual of 25mm carapace length. The drag of each pot was measured every 10 times with changing the current speeds from 0.1m/s to 0.7m/s in 0.1m/s intervals and the pot attack angle from 0˚ to 90˚ in 15˚ interval in a flume tank. The relation between the current speed and drag was presented. The stability of pot was estimated using the drag data and the friction data of Kim et al. (2008b). The results showed that, the drag was shown lower as small as the projected area of pot depending on the current speeds and angles. The model pots were showed to slide on the seabed in case of rock at the current speeds 0.35-0.38m/s and the possibility of turn over at the current speeds 0.77-0.89m/s. In conclusion, the stability of a shrimp pot showed more stable as the pot of the lower the height and the smaller projected area on current.
Test fishing was carried out using six kinds of different mesh sizes (20, 22, 24, 28, 35, 40mm) for springnet-pot to study bycatches according to the mesh size and catches survey was done for another one (mesh size : 22mm, entrance round : 350mm) in Geo-je & Tong-young waters of Korea. On the first sea experiment, it was thought that suitable mesh size of spring-net-pot catching conger-eel over 35cm with decreasing the catches of conger-eel (Conger myriaster) below 35cm was 24mm. On the second sea experiment, commercial catches were crabs (Charybdis bimaculata), octopus minor (Octopus variabilis) and others including conger-eel, and catches proportion was 60% of total catches weights. There was no big difference for the monthly catches. Self-consumption catches were 9 species including conger-eel below 35cm holding 50% of catches in the side of weights. There were 40% of bycatches for the catches weights and 63% for catches numbers in the 22mm mesh size of spring-net-pot having entrance round over 140mm. It showed that 50% of catches weights were discarded.
In this study, the effect of slope length and angle at the entrance to fishing pots on the size of captured shrimp was examined to determine the optimal design of pots for use in Hokkaido, Japan. The purpose of the current study was to optimize the design of shrimp pots to allow greater control over the size of captured individuals for the purposes of shrimp resource management. Tank experiments were conducted to determine the optimal slope length and slope angle by analyzing the sizes of shrimp entering 10 model pots with combinations of five different slope lengths on slope angle of current shrimp pot, and five different angles on slope length of current shrimp pot. The results showed that, as the slope length of the pot increased, the size of individuals which entered the pot increased. In addition, as the slope angle was elevated in each of the five different slope angle treatments, the size of individuals entering was also increased.
To increase pot life in the formulation mixed with bisphenol F epoxy resin, anhydride-based curing agent, and imidazole-based curing accelerator powders as a paste material for high-speed RFID chip bonding, size variation of the imidazole-based powders and a coating method of the powders were adopted in this study. In experiment with regard to the size variation, the pot life was not outstandingly increased. Through the idea using the coating method, however, the pot life was increased up to 4.25 times in comparison with the addition of initial imidazole-based powders. Consequently, successive bonding of RFID chip could be performed with very short time of 5sec using the suggested formulation having improved pot life.
본 연구는 매발톱꽃의 형태 및 생육량에 대한 차광 및 화분 크기의 효과를 구명하여 조경용 지피식물로서의 적용방안을 제안하고자 수행되었다. 차광률에 따른 엽병수와 엽병장의 증가는 통계적으로 유의성 있게 차광 60, 30, 0, 80% 처리구 순으로 높게 나타났으며 차광 30~60% 처리구에서 도장하지 않고 양호한 형태를 나타냈다. 차광 80%에서는 분명하게 도장하며 불량한 형태를 보였다. 잎 두께는 무처리구에서 가장 높게 나타났고 차광 80%에서는 가장 낮게 나타났다. 차광률에 따른 생육량의 증가는 차광 60, 30, 0, 80% 처리구 순으로 높게 나타났다. 화분 크기에 따른 형태 및 생육량을 전반적으로 살펴보면, Pot B(D90×H100mm)와 비교하여 Pot A(D155×H150mm)에서 자란 식물체가 통계적 유의차를 가지고 우수하게 나타났다. 조경용 지피식물로서 매발톱꽃은 차광 30~60% 처리구와 유사한 광도를 가지는 가로수 주변, 침엽수림 하부, 독립수로 식재된 느티나무(H6.0×R60), 가중나무(H8.0×R50), 은행나무(H5.5×B25) 등과 같은 활엽교목 하부 등에 식재되는 것이 적합하며, 간편한 화단 조성 및 갈이를 위하여 화분에 식재된 식물체를 필요로 하는 경우에는 Pot B보다는 Pot A와 같은 토양환경을 조성하는 것이 바람직하다.
향끽미종인 소향을 공시하여 묘상면적과 이식노동력을 절감하는 육묘방법과 적정재식밀도를 구명하기 위하여 가식의 여부, 육묘용비닐포트의 크기(3.5cm×3.5cm, 4cm×4cm and 5cm×5cm) 및 혈당주수(1, 3, 5, 7, 9주)를 달리하여 실시한 결과를 요약하면 다음과 같다. 1. 혈당건물중 및 L. A. I는 혈당주수가 많을수록 증가하였으나 1엽중, 1엽면적, 단위엽면적중, 액아발생량 및 엽면조도는 감소하였고 포트의 크기에 따른 차이는 통계적으로 유의성이 인정되지 않았다. 2. 생존율은 가식여부에 따른 차이는 없었고 3.5cm 포트가 컸으나 5cm포트에 혈당 7주까지는 재배상의 문제가 없을 것으로 생각되었다. 3. 니코틴은 혈당주수가 많을수록 감소하였으나 포트의 크기에 따른 차이는 통계적으로 유의성이 인정되지 않았다. 4. 수량, kg당 가격 및 10a당 대금은 가식여부 및 포트의 크기에 따라 통계적인 유의성이 인정되지 않았으나 혈당주수가 많을수록 증가하였다. 5. 완화성 및 팽숭성은 혈당주수가 많을수록 좋아졌고, 연소성도 혈당 5주 이상이 혈당 1-3주보다 좋았다. 6. 향끽미종잎담배인 소향의 재부는 가식을 성략하여 5cm×5cm 포트에 혈당 6주를 육묘하는 것이 바람직하다.