• 한국국제농업개발학회지
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• 제30권4호
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• pp.370-375
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• 2018

본 연구는 근래에 건강 기능성효과가 널리 알려지면서 수요가 증가함에 따라 재배면적과 생산량이 증가하고 있는 종실용 들깨의 기계화재배를 촉진하기 위하여 수확 때 종자탈립에 의한 손실률은 최소화하고 수량성을 높일 수 있는 최적 파종시기를 설정하고자 수행하였다. 1. 파종기가 늦어질수록 파종후 개화기까지 생육일수는 짧아져 6월 15일 파종대비 6월 30일, 7월 15일 및 8월 1일 파종에서 각각 14일, 26일 및 31~32일 짧아졌으며, 또한 경장과 경태는 짧아지거나 가늘어졌으며 마디수가 적어지는 경향을 나타냈다. 2. 유효분지수는 6월 15일 파종대비 6월 30일, 7월 15일 및 8월 1일 파종에서 각각 82%, 61% 및 56%로 7월 15일 파종부터 급격히 낮아져 수량성 확보에 불리한 것으로 판단되었다. 그리고 최저화방군의 높이는 파종기가 늦어질수록 대체로 짧아지는데, 소담의 7월 15일과 8월 1일 점파구의 경우 15 cm 이하로 예취기를 이용한 기계수확에 불리하게 작용할 것으로 판단되었다. 3. 파종기와 수량성 간에는 고도의 유의성이 인정되었는데, 총수량은 6월 15일, 6월 30일 및 7월 15일 파종에서 통계적 유의차는 없었지만, 종실탈립률의 경우 7월 15일, 8월 1일(30.3%) > 6월 15일(15.3%) > 6월 30일(13.5%) 파종의 순이었는데, 탈립된 종실을 제외한 순수량은 6월 30일$${\geq_-}$$6월 15일 > 7월 15일 > 8월 1일 파종 순으로 높게 나타났으며 이러한 경향은 품종 및 파종방법에 관계없이 나타나는 일반적인 특징이었다. 4. 들깨 종실의 단백질 함유율은 파종기가 늦어질수록 대체로 증가하여 8월 1일 파종에서 가장 높았으며, 조지방 함유율의 경우 소담은 6월 15일과 7월 15일 파종에서, 들샘은 6월 30일과 7월 15일 파종에서 비교적 높았으며, 리놀렌산의 함량율은 8월 1일 파종에서 특이적으로 높은 수준을 나타냈다. 5. 위의 결과, 종실용 들깨의 예취기를 이용한 기계수확을 위한 최적 파종시기는 6월 30일 경으로 이때 파종하면 수확 때 종실탈립에 의한 손실률은 최소화하면서 수량증대에 유리하여 기계수확에 가장 적합한 파종시기로 판단되었다.

• 한국발생생물학회지:발생과생식
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• 제17권4호
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• pp.353-361
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• 2013

The objective of this study was to characterize the reproductive cycle of the chameleon goby, T. trigonocephalus. Gonadal development was investigated using a histological method. Specimens were collected monthly, from April 2009 to March 2010. The gonadosomatic index (GSI) of females began to increase in April, reaching the maximum in May, and declined sharply in August. In males, the GSI began to increase in April and reaching the maximum in July. The annual reproductive cycle of T. trigonocephalus can be divided into four successive stages in females: the growing (November-March), maturing (April-May), ripe and spawning (June-July), and recovery (August-October) stages. Males passed through growing (November-March), maturing (April-June), ripe and spermiation (July-August), and recovery (September-October) stages. These results indicate the spawning season is from June to July. The relationship between fecundity (Fc) and body length (BL) was $Fc=86.1511BL^{2.6506}$. Fecundity was ranged from 3,448-9,654 eggs in a BL of 4.8-7.2 cm and it was increased as BL increased.

• 수산해양기술연구
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• 제35권3호
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• pp.267-276
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• 1999

In order to investigate the properties in distribution and movement of anchovy school catches by the lift net in the Kamak bay and their relation to the environmental factors, i.e., the water temperature and the salinity were observed form June to August in 1997 and compared with the catch of anchovy by the lift net. The results obtained are summarized as follows;1) The water temperature and salinity ranged form 20.0 to $27.0^{\circ}C\;and\;from\;31.2\;to\;33.8\texperthousand$, respectively. The water temperature and salinity at the fishing points ranged form 19.7 to $27.2^{\circ}C\;and,\;from\;30.5\;to\;33.8^{\circ}C$ respectively.2) The water temperature influenced remarkably on the distribution and movement of anchovy school. But the salinity influenced little on the distribution and movement. 3) The catch of anchovy was highest on July, poor second on August, and lowest on June. Anchovy school can be presurmed, they are come from north of bay, visited and distributed through east of bay at the middle of June. Moreover, they spreaded in all bay. Then gradually, when July arrive, they go to the south th nearest the coasts, and they are outflow through the south entrance of bay at the end of August.

• 한국농림기상학회지
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• 제5권4호
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• pp.218-225
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• 2003

본 실험은사과원의 위치에 따라 국지기후조건이 다양함을 보여주었으며, 이와 같이 다양한 기후환경은 과실의 품질에 직간접적으로 많은 영향을 미치고 있는 것으로 조사되었다. 즉, 당함량과 anthocyanin 함량은 8월의 평균기온에 따라 다른 것으로 나타났으며 일정한 상관관계를 가지고 있었다. 또한 4월에서 8월까지의 평균기온과 과육의 경도 사이에 일정한 상관이 인정되었으며, 4월에서 8월까지의 최고기온과 Hunter a값 사이에도 상관관계가 인정되었다. 이러한 기후조건의 범위는 세포조직학적 특성에도 영향을 미쳤으며, 온도는 과피층 세포의 수와 크기에 영향을 주었다. 따라서, 사과 주산지의 과실 품질은 기후의 영향을 크게 받아 매우 다양하게 나타나는 것으로 조사되었다.

• 한국환경과학회지
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• 제17권11호
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• pp.1281-1293
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• 2008

This study aims at the estimation of dam failure time and dam failure scenario analysis of and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-HMS, DAMBRK-FLDWAV simulation model. As the result of the rainfall-runoff simulation, the lancet flood amount of the Yeoncheon Dam site was $10,324\;m^3/sec$ and the total outflow was $1,263.90\;million\;m^3$. For the dam failure time estimation, 13 scenarios were assumed including dam failure duration time and starting time, which reviewed to the runoff results. The simulation time was established with 30 minutes intervals between one o'clock to 4 o'clock in the morning on August 1, 1999 for the setup standard for each case of the dam failure time estimation, considering the arrival time of the flood, when the actually measured water level was sharply raising at Jeongok station area of the Yeoncheon Dam downstream, As results, dam failure arrival time could be estimated at 02:45 a.m., August 1st 1999 and duration time could be also 30 minutes. Those results and procedure could suggest how and when dam failure occurs and analyzes.

• 수산해양기술연구
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• 제45권4호
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• pp.287-291
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• 2009

This study examined the maturation and main spawning season of Japanese spear lobsters, Linuparus tirgonus(Von Siebold) captured around Jeju island from January to September, 2008. Carapace length(CL), body weight(BW) and gonad weight(GW) were measured. Gonadosomatic index(GSI) and sex ratio were calculated. In female group, CL showed the highest value in June and decreased after August. GW showed a peak in July and decreased rapidly after August. The mean gonadosomatic Index(GSI) reached a maximum value between June and August. Number of egg ranged from 143,360 to 189,504.

• Fisheries and Aquatic Sciences
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• 제6권2호
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• pp.51-58
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• 2003

The gonadal development and the gametogenic cycle and the fine structure of ripe germ cells of the cultured Pacific oyster, Crassostrea gigas were investigated using oysters monthly collected from the southern coast of Korea from October 2000 to September 2001. Monthly changes in the condition index were similar to that of meat weight rate and the highest value was observed in between April and May, and the lowest value in August. The external colors of the testis and the ovary were milky white and yellowish, respectively. The spawning period of the Pacific oyster was continued from May to September, with a peak in July. The gametogenic cycle could be classified into five successive stages: multiplicative stage (December to March), growing stage (March and April), mature stage (April to June), spawning stage (June to August) and resting stage (August to January). Variety of egg yolk granules, lipid granules, mitochondria, and endoplasmic reticula were observed in cytoplasm of ripe oocyte. The spermatozoon consisted of the head, middle piece and tail; including cap-shaped acrosome with domed structure, elliptical shaped nucleus, four mitochondria, two centrioles and flagellum.

• Fisheries and Aquatic Sciences
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• 제2권2호
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• pp.142-148
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• 1999

Monthly changes in the gonad index (GI), egg-diameter composition, gonadal development, reproductive cycle of the ark shell, Scapharca subcrenata, were investigated by histological method and morphometric data. This species is dioecious and oviparous. The gonad is located among the subregion of mid-intestinal gland, digestive diverticula and the outer fibromuscular layers compacted by the fibrous connective tissues and muscle fibers. The gonad index sharply increased in May, reached the maximum value in June, and then gradually decreased from July to December. The reproductive cycle of this species can be divided into six successive stages: early active stage (January to May), late active stage (June to July), ripe stage (June to August), partially spawned stage (July to September), degenerative stage (August to December), and resting stage (January to April). S. subcrenata spawns once a year between July and early September, and the main spawning occurred between July and August when the water temperatures were above $20^{\circ}C$. This evidence suggest that timings of maturation and spawning are closely related to water temperatures. Even though the spawning period was once a year, it is assumed that the number of spawning frequencies (broods) may occur more than twice during the spawning season.

• 한국환경과학회지
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• 제10권1호
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• pp.27-33
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• 2001

In order to study the long-term change of heavy metal concentrations in the Kumho river water, water analysis was conducted at 13sites surrounding the Kumho river system for 18times from September 1993 to August 1999. Analytical items for the study of water quality are Cu, Zn, Cd, Cr, Fe, Mn and Pb. The six year term studied in this work was divided into Part I and Part II, which covers the period from September 1993 to August 1996 and the period from September 1996 to August 1999, respectively. The mean concentrations of Cu, Zn, Cd, Cr, Fe, Mn and Pb in the unit of ppm for the Part I period showed 0.032, 0.025, 0.006, 0.050, 0.053 and 0.019, respectively. The mean concentrations of Cu, Zn, Cd, Cr, Fe, Mn and Pb in the unit of ppm for the Part II period showed 0.001, 0.001, 0.001, 0.004, 0.020, 0.002 and 0.002, respectively. The heavy metal concentrations in the Kumho river water for te second period were found to be decreased by 1/32, 1/25, 1/6, 1/1.5, 1/2.5, 1/26.5 and 1/9.5 for Cu, Zn, Cd, Cr, Fe, Mn and Pb, respectively. The present results clearly indicate that the water quality in the Kumho river is improving in terms of heavy metal contaminations.

• 한국환경과학회지
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• 제13권6호
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• pp.561-570
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• 2004

This study was carried out to survey the pollution of nonylphenol (NP) in surface sediments around Gwangyang bay and Yeosu sound. NP was suspected chemicals as endocrine disruption. Gwangyang bay is located on the mid south coast of Korea. It is a semi-closed bay which Yeosu petrochemical industrial complex, POSCO (Pohang Steel Company) and Gwangyang container harbor are there. The surface sediments were collected at 15 stations with gravity corer at October, 1999, February, May and August, 2000. Also, the stream and intertidal sediment were collected at 5 sites at August, 2000. Concentrations of NP in surface sediments were in the range of 6.89 to 202.70 ng/g dry wt.. Seasonal range (mean value) of NP is 13.98 to 30.48 (23.46) ng/g dry wt. at October, 10.35 to 54.91 (28.10) ng/g dry wt. at February, 29.05 to 202.70 (82.32) ng/g dry wt. at May and 6.98 to 83.40 (25.37) ng/g dry wt. at August. NP was seasonally fluctuated, and the highest mean value and range was detected at May, 2000. NP was highly distributed in the inner part of Gwangyang bay than Yeosu sound. Concentrations of NP in stream and intertidal sediments showed the highest value in downstream near Yeosu petrochemical industrial complex and Yondung stream. It suggests that the source of NP is industrial wastewater and municipal sewage.