• Journal of the korean society of oceanography
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• v.39 no.2
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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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• v.8 no.3
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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.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.237-240
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• 2006

Seventy-one marine bacteria decomposing sea tangle (Laminaria japonica) into single cell detritus (SCD) were isolated from sea water, sea tangle, sea mustard (Undaria pinnatifida), sea urchin (Anthocidaris crassispina), star fish (Acanthaster planci), and turban cell (Batillus cornutus), among which 14 strains decreased cutting strength of sea tangle and had alginate-degrading activity. Marine bacterium No. 34 isolated from turban cell showed lowest cutting strength of sea tangle, strongest alginate-degrading activity, and produced high content of $5-10\;{\mu}m$ SCD from sea tangle. This strain was identified as Vibrio sp. based on morphological, physiological, and biochemical characteristics and named as Vibrio sp. YKW-34.

• Journal of Wetlands Research
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• v.8 no.3
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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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.606-612
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• 2006

Obtaining powder form of seaweed is essential for the use of seaweed as a food additive. The deterioration of seaweed caused by high temperatures during homogenization and powder processing is a serious problem and limits the use of seaweed as a food or pharmaceutical ingredient. Furthermore, many powder particles are not fluidized very well because of the interaction between particles. In order to solve this problem, sea tangle was hydrolyzed to a level of single cell detritus (SCD) by Vibrio sp., isolated from Batillus cornutus. with strong hydrolytic activity. The crude protein and amino acid contents of sea tangle SCD were higher than those of the powder, whereas the reverse was true for ash content. Sea tangle powder contained more mineral than its SCD, whereas total amino acid content was 5 times more in SCD than in power. The anticancer activities of sea tangle SCD and powder were 31.20 and 29.07%, respectively, with no significant difference (p<0.05), but about 15% higher than that of the control. The ACE inhibitory activity of the sea tangle powder, 39.31%, was higher than the 26.07% of the SCD. The antithrombin activity of the sea tangle powder, 55.3 seconds, was higher than the 34.5 seconds of the SCD. Moreover, there was no antioxidative and ischemic activities in both tile sea tangle powder and SCD.

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.37-38
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• 2005

• Proceedings of the KGS Conference
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• 2002.05a
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• pp.144-147
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• 2002

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.68-74
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• 2006

To utilize sea tangle single cell detritus (SCD) as food additive, SCD noodle was developed using mixture model. Flour improved, whereas water decreased texture of SCD noodles. Texture of SCD noodle decreased initially and then increased as SCD content increased. Flour and SCD increased, whereas water decreased $L^*$ and $b^*$ values of dried and cooked noodles. Flour decreased $a^*$ values of dried and cooked noodles, while SCD increased $a^*$ value of cooked noodle. Response constraint coefficient showed SCD influence on texture, and $L^*$ and $b^*$ values of dried and cooked noodles was higher than those of flour and water, whereas water influence on $a^*$ value was higher than those of flour and SCD. Texture and color values fitted nonlinear model with interaction terms for flour-water, flour-SCD, and water-SCD. Optimum mixing ratio value of flour : water : SCD was 63.3 : 31.0 : 3.7%. Sensory evaluation value of SCD noodles was lower than those of industrial and electrolyzed SCD noodles.

• Fisheries and Aquatic Sciences
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• v.26 no.8
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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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• v.26 no.8
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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.