• 수산해양기술연구
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• 제35권3호
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• pp.227-236
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• 1999

Temperal and spacial analysis for catches have been drawing up a catch distribution chart and analysing catches and CPUE(Catch Per Unit Effort) using catch data with purpose of obtaining basic data to establish a selective method of effective fishing the tuna purse seine fishing ground.The temperature profile section and catch was surveyed to analyse the effect of catch in relation to the fishing ground environment.The results are as follows ;1. As for the catch variation between 1983 and 1984, the catch mainly took place on150^{\circ}E$, and after that it moved eastward enlarging the range of catch. In the monthly catch variation between January and February, the catches mainly happened on 135$^{\circ}$~ 150$^{\circ}$E, and then moved to the gradually westward. However, from July it moved to the South and from October Southeast.2. As to the eatch ratio for the school associated with the drifted object, the pelagic migrating school and the school associated with the biological objects, the catch ratio for the school associated with the drift objects was the highest. The catch ratio for the school associated with the drifted object was high in June, July and November whiles between January and March for the pelagic migrating school.3. SST(Sea Surface Temperature) was around 28~29^C$ on the observing line of 137^{\circ}E$ and the catches took place in the north equatorial counter-current situated on around $5^{\circ}~6^{\circ}N$. SST in the northern summer was 1^C$higher than winter and it was about 29~30^C$. The catch happened with the center of north equatorial counter-current. The reason why the catch mainly took place on the north equatorial counter-current is that main catch of tuna purse seine was the school associated with drift objects. It is thought that the fishing grounds are made in waters that have many drift objects like drift logs from the coast.

• The Plant Pathology Journal
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• 제35권6호
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• pp.585-597
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• 2019

A disease forecast model for Marssonina blotch of apple was developed based on field observations on airborne spore catches, weather conditions, and disease incidence in 2013 and 2015. The model consisted of the airborne spore model (ASM) and the daily infection rate model (IRM). It was found that more than 80% of airborne spore catches for the experiment period was made during the spore liberation period (SLP), which is the period of days of a rain event plus the following 2 days. Of 13 rain-related weather variables, number of rainy days with rainfall ≥ 0.5 mm per day (L_day), maximum hourly rainfall (P_max) and average daily maximum wind speed (W_avg) during a rain event were most appropriate in describing variations in airborne spore catches during SLP (S_i) in 2013. The ASM, Ŝ_i = 30.280+5.860×L_day×P_max-2.123×L_day×P_max×W_avg was statistically significant and capable of predicting the amount of airborne spore catches during SLP in 2015. Assuming that airborne conidia liberated during SLP cause leaf infections resulting in symptom appearance after 21 days of incubation period, there was highly significant correlation between the estimated amount of airborne spore catches (Ŝ_i) and the daily infection rate (R_i). The IRM, ${\hat{R}}_i$ = 0.039+0.041×Ŝ_i, was statistically significant but was not able to predict the daily infection rate in 2015. No weather variables showed statistical significance in explaining variations of the daily infection rate in 2013.

• 수산해양기술연구
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• 제49권3호
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• pp.218-226
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• 2013

The objective of this study is to estimate the optimal net twine thickness of drift net for yellow croaker. The filed experiments of the fishing performance were conducted with three kinds of drift net with different monofilament diameters (No.3=0.284mm, No.4=0.330mm, No.5=0.370mm) the total eight times in the southwest coastal sea of Korea. And the physical properties tests on the monofilaments of experimental net were carried out to estimated breaking load and softness in dry and wet conditions, respectively. From the results, the No.3 mono. was the strongest break load per unit area in dry and wet conditions. And the softness showed that the No. 3 mono. was the most soft than another experimental monofilaments. The fishing performance was; the No. 3 drift net showed the most catches. Conversely, the catches of No. 4 and No. 5 drift net showed the half on the catches of No. 3 drift net. Consequently, the diameter of monofilament in the drift net for yellow croaker should carefully choose to consider the economic sides such as the amount of catches and the cost of catches.

• 한국재난정보학회 논문집
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• 제18권1호
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• pp.194-201
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• 2022

연구목적: 본 연구는 지난 30년(1981~2010년) 동안 우리나라 기후 요인과 근해 어업에서 어획량의 관계를 조사 분석하였다. 연구방법: 본 연구에서 어획량은 한국인 식탁에서 선호되는 7가지 어종을 대상으로 하였다. 본 연구에서는 장기적 추세를 쉽게 파악할 수 있도록 10년 이동평균을 사용하였다. 연구결과: 동 기간 동안 우리나라 연안의 기온과 표층수온(SST)은 모두 상승하였다(p < 0.05). SST의 상승은 기온의 상승과 유의한 상관관계가 있었지만(p < 0.05), 강수량과는 상관관계가 없었다. 2010년에는 1981년에 비해 멸치와 오징어 어획량이 크게 증가한 반면(p < 0.05), 명태는 거의 멸종되어 어획량이 거의 없었다. 이처럼 냉수 어종은 감소하거나 사라지고 어장은 온수 어종으로 대체되었다. 결론: 이러한 결과는 우리나라 근해 어업에서 어획되는 어종이 기후변화, 특히 온난화로 인해 변화했음을 나타낸다. 이는 한반도의 온난화가 가까운 장래에 한국인의 수산물 공급과 식량 안보에 중대한 영향을 미칠 수 있음을 시사한다.

• 한국식물병리학회지
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• 제11권3호
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• pp.230-237
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• 1995

Airborne and waterborne ascospores and conidia of Botryosphaeria dothidea were collected in apple orchards at Suwon and Chunan in 1992 through 1994. Both waterborne and airborne spores were first detected in mid April to early May. Thereafter, spores were abundant in early June to late August and present until early December. Rainwater collections contained much more conidia than ascospores during the apple growing seasons. Airborne ascospores catches, which were also detected on humid days without measurable rainfall, were much more than airborne conidia catches. High amounts of ascospores were detected in early times of apple growing season, whereas most conidia catches occurred in later times of the season. The number of waterborne conidia and airborne ascospores was positively correlated with mean daily maximum, minimum, and average air temperatures during the trapping periods (p=0.01). However, no significant correlation was found between the number of spores and the total precipitation during the trapping periods.

• 한국수산과학회지
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• 제29권2호
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• pp.197-207
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• 1996

한국 다랭이 선망어선의 유목군 조업 비율은 최근 까지 점차 감소 추세에 있으며 $1990\~1995$년간의 유목군 어획 비율은 전체 어획량의 $34.6\%$로 선망어업 초기와 비교해 볼 때 상당히 낮았다. 어획 어종의 조성에서는 유목군 및 부상군 조업에서 다같이 가다랭이가 가장 많이 어획되었고 그 다음 황다랭이 그리고 소량의 눈다랭이가 어획되었다. 황다랭이의 어획 비율은 부상군 조업이 유목군 조업보다 높았다. 승선 조사 시의 유목군 조업의 어획 어종의 조성은 가다랭이 $60\%$, 황다랭이 $38\%$, 눈다랭이 $2\%$로 조업 실적 자료보다 가다랭이는 낮았고 황다랭이는 높았다. 유목군 조업에서 혼획된 종은 모두 11종이었으며 그중 상어류가 전 투망 시에 어획되었고 yellowtail kingfish가 마리수로는 가장 많이 어획되었다. 황다랭이의 체장 조성을 비교하였을 때 소형 황다랭이는 주로 유목 주변에 분포하는 것으로 나타났다.

• 해양환경안전학회지
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• 제23권7호
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• pp.909-917
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• 2017

본 연구에서는 동해 연안의 경상북도(경북)와 강원도(강원)의 정치망어업에서 31년(1980~2010)간 5~11월에 어획된 방어 어획량과 연근해 수온과의 관계를 살펴보았다. 또한, NOAA 수온 영상을 이용하여 수온의 상승과 하강 시기에 외해수의 이안 및 접안으로 인한 방어의 북상시기(5~8월)와 남하시기(9~11월)의 어획량 변동을 분석하였다. 전체 방어 어획량의 변동은 연도별 차이는 있지만 방어의 북상 시기보다 남하시기에 높은 수온의 외해수가 연안에 접안할 때 어획량이 증가였다. 연안수온의 하강기는 북상 및 남하하는 모든 시기에 경북이 강원보다 방어 어획량이 많았다. 수온 상승기는 방어 어획량의 증감이 동시에 나타났고, 남하시기의 방어 어획량은 일반적인 현상과 달리 강원이 경북보다 어획량이 많았다. 이것은 하계의 $25^{\circ}C$ 이상의 수온이 강원도까지 분포하면서 추계까지 높은 수온($20^{\circ}C$)이 지속되어 방어의 체류시간이 길어졌기 때문이다.

• 수산해양기술연구
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• 제33권2호
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• pp.97-108
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• 1997

황해와 동중국해역에서 근해안강망에 의해 어획되는 황아귀의 어획량 변동과 어장 분포, 그리고 산란 생태를 구명한 결과는 다음과 같다. 황아귀는 연중 어획되며, 이중 많이 어획되는 시기는 겨울철, 가장 적게 어획되는 시기는 여름철인 것으로 나타났다. 황아귀의 어장은 황해와 동중국해에 널리 분포하고 있으며, 중심어장은 일향초 주변 해역으로 어획량이 50 M/T 이상, CPUE가 5kg/haul 이상, C.V는 0.6~0.7의 범위로 낮게 나타났다. 황아귀의 산란시기는 3월과 4월경이며, 이때의 산란장은 일향초와 제주도 사이해역에서 형성되는 것으로 추정되었다. 황아귀의 어장은 월별에 따라 이동하는 현상을 나타내었는데, 즉, 겨울에는 황해저층냉수와 대마난류수의 남하로 어장은 제주도 서방해역에 주로 분포한다. 또 산란시기인 3월과 4월경이 되면, 일향초 부근 해역으로 어장이 밀집하지만, 산란이 끝난 5월이후가 되면 수온의 상승과 더불어 어장은 황해와 동중국해역으로 널리 분산되는 것으로 나타났다.

• 수산해양기술연구
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• 제47권1호
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• pp.10-17
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• 2011

Biodegradable octopus pot was developed to reduce plastic pollution problem in the sea and fishing trouble between fishermen. It can be expect to recycle other wasted biodegrade fishing gear. Experimental fishing was carried out to understand the difference in fishing efficiency between Polyethylene (PE) octopus pots and biodegradable (Polybutylene Succinate and Polybutylene adipate-co-terephthalate) octopus pots which was tried to make in this study in the sea. There were caught by 237 numbers of fishing during the experimental period. Among the 237 numbers of fishing, 160 or 67.5% were PE pots which were more than the biodegradable pots. A comparison of the monthly catches between the PE pots and biodegradable pots shows that the catches were overall higher in the PE pots than in the other pots. The result is very similar with the comparison of total catches by each type of the pots. In terms of bycatch, the number of species, amount of catches and the number of fishing with bycatch were more significant in the biodegradable pots than in the PE pots.

• 수산해양기술연구
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• 제41권3호
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• pp.179-187
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• 2005

This study was conducted in order to the experiment of bottom trawl fisheries in the sea mount of central northern pacific($30^{\circ}-40^{\circ}N$, $170^{\circ}-175^{\circ}E$), during the period of July 1 to August 25, 2004 by commercial trawl ship. Fishing experiment was carried out by bottom trawl, with the codend of 110mm mesh size. The number of 101 test fishing was done in the sea mount of central northern pacific during 56 days and the total catches were 198,593kg as 18 fish species, and CPUE/day and catches/day were 8.3 hours towing time and 3,546kg. Catch ratio according to each fishing ground was higher with the order of B, C, and E, and catches for B was 7,171.0kg during the towing time of 13.2 hours. Main target species were Pseudopentaceros richardsoni and Beryx splendens, there was 14.9% of damage ratio for fishing gears on catching the target fishes inhabiting on the rough sea bottom. Catches by water depth was the order of 300m below, 301-350m, 451-500m and 351-400m. It is thought that there was no problem on the mesh size because most of fishes caught from the experimental fishing was 30cm over.