• Journal of the korean society of oceanography
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• 제39권2호
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• pp.136-147
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• 2004

Different model formulations in available models were compared with Microplankton-Detritus (MPB) model, and well documented FDM and ERSEM models were the candidate for these comparison. Different formulations in both candidate models were expressed in terms of MPD parameterization. Even though there are differences in the control of autotroph growth among models, it was found that some of the more important microplankton parameters expressed incomparable terms have broadly similar values in all the models. However, an important difference was proved to be the direct contribution of microheterotrophs to the Detritus compartment in FDM and ERSEM, whereas in MPD microplankton biomass passes to Detritus only by way of mesozooplankton grazing.

• The Korean Journal of Ecology
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• 제8권3호
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• pp.153-161
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• 1985

Energy flow through the trophic levels was studied at a salt marsh ecosystem distinguished into low and high marsh. Gross primary productions of Suaedeto-Salicornietum and Artemisieto-Limonietum at low marsh were 8, 299 and 13, 154kca/$m^2$/yr, and those of Calama-grostetum and Sonchuso-Setaetum at high marsh were 17, 899 and 15, 177kca/$m^2$/yr, respectively. Efficiencies of solar energy utilization of plants were 1.7 and 2.6% at the former, and were 3.6 and 3.2% at the latter. Of gross productions, net primary productions were 3, 977 and 5, 280kca/m2/yr at low marsh and were 6, 354 and 5, 329kca/$m^2$/yr at high marsh, and the remainder, 52~67%, was consumed by respiration of plants. A small amount (0.03~0.04%) of the net primary production was flowed through grazing food chain and most amout was transferred into dead parts. Of dead parts, 40% was accuulated as litter and the rest was decomposed into detritus. In the detritus food chain, a little energy was utilized by detritus feeder, and a major by microorganism. The amounts of energy flowed through grazing and detritus feeders at high marsh were much more than those at low marsh, but tertary production as spider was Vice versa.

• 한국식품과학회지
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• 제38권2호
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• pp.237-240
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• 2006

다시마(Laminaria japonica)를 기능성 식품소재로 활용하기 위한 예비단계로, 다세포의 다시마를 미립자의 single cell detritus(SCD)로 분해하는 해양세균을 해수, 다시마(Laminaria japonica), 미역(Undaria pinnatifida), 성게(Anthocidaris crassispina), 불가사리(Acanthaster planci), 소라(Batillus cornutus)로부터 분리하였다. 분리한 71개의 균주 중 다시마 조체의 연화능과 알긴산 분해활성을 동시에 가지는 균주는 14개이었으며, 균주 No. 34가 가장 강한 다시마 조체의 연화능과 알긴산 분해활성을 나타내었다. 균주 No. 34는 배양 15일 만에 다세포의 다시마를 미립자의 SCD 형태로 분해하였으며, 그 크기는 $5-10{\mu}m$이었다. 균주 No. 34는 vibrio sp.으로 동정되었으며, Vibrio sp. YKW-34로 명명하였다.

• 한국습지학회지
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• 제8권3호
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• pp.39-49
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• 2006

Seasonal biomass and carbon, nitrogen contents change of marsh club-rush (Schoenoplectus trigueter) was investigated in Nakdong river estuary, located near Busan, Korea. New shoot of S. trigueter sprouted from tuber in April and fast growth season was followed until mature in August. Mature lengths of shoot and root were 60 and 9.4 cm, respectively. The increase of biomass showed similar seasonal trends with length. Mature biomass were $3.5gind^{-1}$ in wet weight and $0.6gind^{-1}$ in dry weight. The biomass of S. trigueter in areal basis was also highest during July and August ($186gDWm^{-2}$). The shoot of S. trigueter was disappeared in October from the ground but the biomass of shoot was maintained as a form of detritus in sediment. The amount of S. trigueter detritus was about 30~50% of the biomass in August. During winter, the amount of detritus decreased with time but the biomass of root+tuber remained same, implying the root+tuber part is alive. The net productivity of S. trigueter estimated from biomass change were $538gDWm^{-2}yr^{-1}$, $240g-Cm^{-2}yr^{-1}$, $8.2g-Nm^{-2}yr^{-1}$ in dry weight, carbon and nitrogen equivalent respectively. During winter, carbon to nitrogen ratio in detritus increased implying the preferred remineralization of nitrogen during microbial degradation.

• 한국식품영양과학회지
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• 제35권5호
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• pp.606-612
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• 2006

해조류를 식품으로 이용하기에는 분말화가 필수적이나 분쇄 등의 분말화 과정에서의 온도상승은 이들 생리활성성분의 열화를 가져올 수 있으며, 수십$\sim$수백 ${\mu}m$의 분말입자는 입자 상호간의 응집으로 인하여 유동성이 좋지 않다. 해조류의 기계적 분쇄의 단점을 해결하기 위하여, 다시마(Laminaria japonica)의 분해능이 강한 Vibrio sp.를 소라(Batillus cornutus)에서 찾아 다시마 SCD(Single Cell Detritus)를 제조하였으며 SCD가 가지는 여러 가지 성분 및 생리활성을 분석하였다. 다시마 SCD의 조단백 함량과 총아미노산의 함량은 다시마분말보다 높았으나 ash의 함량은 낮았다. 다시마 SCD와 분말시료의 항암활성은 각각 31.20과 29.27%로 차이가 없었다(p<0.05). ACE저해효과는 분말시료가 39.31%로 SCD의 26.07%보다 약간 높았다. 항혈액응고 측정 결과 다시마분말은 55.3초로 다시마 SCD의 34.5초보다 높았다. 또한 다시마 SCD와 분말은 항산화효과와 뇌허혈에 의한 신경세포사 억제효과는 없는 것으로 나타났다. 비록 다시마 SCD의 생리활성은 분말보다 약간 떨어지나 조단백질, 아미노산 및 지질의 함량이 높기 때문에 빵, 국수 및 수산 연제품 등의 첨가제로서 응용할 수 있는 큰 장점이 있다고 판단된다.

• 한국수산학회:학술대회논문집
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• 한국수산학회 2005년도 춘계학술대회
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• pp.37-38
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• 2005

• 대한지리학회:학술대회논문집
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• 대한지리학회 2002년도 춘계학술대회 요약집
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• pp.144-147
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• 2002

• 한국식품과학회지
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• 제38권1호
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• pp.68-74
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• 2006

다시마를 Vibrio sp.로 분해하여 제조한 SCD를 modified distance design의 최적 배합 비율에 따라 기능성 국수를 제조하였다. 밀가루의 함량이 증가할수록 다시마 SCD 국수의 texture parameter논 증가하였고, 물의 함량이 증가할수록 texture parameter는 반대로 감소하였으며 SCD의 함량이 증가할수록 texture parameter는 감소 후 증가하였다. 밀가루와 SCD의 함량이 증가할수록, 물의 함량이 감소할수록 L 값과 b 값은 증가하였으며, a 값은 밀가루의 함량이 증가할수록 감소하였고 물의 함량이 증가할수록 감소 후 증가하였다. Constraint coefficient 값의 분석 결과 SCD는 건면과 조리면의 texture parameter와 색도의 L(명도) 및 b(황색도) 값, 물은 a(적색도) 값에 가장 큰 영향을 주었으며, hardness를 제외한 texture parameter와 색도에서 원료간의 상호작용이 있었다. Modified distance design에 의해 결정된 최적 배합비율은 밀가루, 물, SCD의 함량이 각각 63.3, 31, 3.7%이었다. 관능검사 결과 잔해수로 처리한 SCD 국수는 시중제품보다 모든 면에서 점수가 약간 떨어지나, 전해수 미처리 SCD 국수보다는 월등히 높은 점수를 받아 전해수의 처리는 본 SCD 국수의 품질향상에 기여할 것으로 판단된다.

• Fisheries and Aquatic Sciences
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• 제26권8호
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• pp.482-490
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• 2023

Food and feeding habits of Labeobarbus intermedius were studied from the newly constructed Ribb Reservoir, Ethiopia during the dry (December-March) season and wet season (June-August) of 2021. The objective of the study was to determine the diet composition, seasonal variation, and ontogenetic dietary shift in the diets of the dominant cyprinid fish in Ribb Reservoir. In this study, frequency of occurrence and volumetric analysis methods were used to present the results. From a total of 203 fish samples, 132 (65%) guts contained food items. Macrophytes (29.4%), phytoplankton (27.2%), detritus (14.8%), and insects (13.6%) were the major food items in the diets volumetrically. During the dry season, L. intermedius was mainly dependent on phytoplankton (58.2%), insects (15.2%), and zooplankton (13.7%) volumetrically. Whereas, macrophytes (50.3%) and detritus (23.3%) were the dominant food items in the wet season. The frequency occurrence and volumetric contribution of the diets of L. intermedius varied significantly (χ² test, p < 0.05) between seasons. Schoener's diet overlap index revealed a slight ontogenetic dietary shift in the diets of L. intermedius. While insects, nematodes, and zooplankton were the main diets of small-sized L. intermedius, macrophytes and detritus were ingested by large-sized L. intermedius. Generally, L. intermedius fed both plant and animal-origin food items and is considered an omnivorous feeder in Ribb Reservoir.

• Fisheries and Aquatic Sciences
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• 제26권8호
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• pp.491-499
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• 2023

Lake Tinisu Abaya is home to some fish species. The lake's native fish species include Barbus and Tilapia zilli. Tilapia fish (Oreochromis niloticus L.) were stocked in Lake Tinishu Aabaya in 1997. This study aimed to investigate the feeding behaviors of O. niloticus in Lake Tinishu Abaya to develop an appropriate fisheries management approach in the lake. 428 O. niloticus fish samples (2.5 to 30.9 cm and 1.1 to 475 g) were collected to calculate the diet composition. Out of the total of 428 gut contents examined, 55 (12.85%) were found to be empty and 373 (87.15%) to be containing one or more food items. The diet behavior of the stocked fish in the study lake revealed that phytoplankton (39.5% by volume) and macrophytes (25.81% by volume) were the most noteworthy food items followed by detritus (14.39%) and zooplankton (12.95%). With increasing fish size, the importance of phytoplankton, macrophytes, and detritus increased while the contribution of zooplankton, insects, and other foods with an animal origin decreased. Seasonal variation in the diet composition of fish was evident (t-test; p < 0.05). Macrophytes, zooplankton, and detritus were the dominating food items during the wet season, while phytoplankton predominated during the dry season. This study demonstrated that O. niloticus had phytoplanktivores that primarily consumed phytoplankton and that the seasons and fish size had a significant impact on their feeding preferences. The diet of O. niloticus in Lake Tinishu Abaya comprised foods with both plant and animal origins. It concludes that the dietary habit of O. niloticus in the lake is, generally, the omnivorous type.