• Title/Summary/Keyword: 섭식강도

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Diversity of Aquatic Insects of Taean Area in South Korea, with Notes on Species-Specific Distribution (태안군 일대의 수서곤충 다양성 및 특이종 분포 양상)

  • Jung, Sang-Woo;Min, Hong-Ki;Hwang, Ho-Sung;Seo, Ye-Ji;Bae, Yeon-Jae;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.30 no.1
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    • pp.58-70
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    • 2016
  • An investigation was carried out to study the diversity of aquatic insects, functional feeding groups (FFGs), habitat oriented groups (HOGs), and species-specific distribution in the Taean area in Korea from June to August, 2015. As a result, a total of 72 species belonging to 30 families and six orders were identified in all the investigated regions. Odonata (22 spp.: 30.56%) was the largest group in species richness followed by Coleoptera (21 spp.: 29.16%), Hemiptera (17 spp.: 23.61%) and Diptera (8 spp.: 11.11%) while for Ephemeroptera and Trichoptera, only two species (2.78%) were found. In addition, Plecoptera and Megaloptera inhabiting clean and flowing waters were not found. In the FFGs, predators (48 spp.: 66.67%) were relatively larger as represented by Odonata, Coleoptera, and Hemiptera, whereas shredders and scrapers were lower in proportion. The dominant groups of HOGs were swimmers (24 spp.: 33.33%), climbers (18 spp.: 25.0%), and sprawlers (12 spp.: 16.67%), which were characterized as aquatic insects community of island. Four species: Cybister lewisianus Sharp, Helophorus auriculatus Sharp, Agrypnia pagetana Curtis, Diplonychus esakii Miyamoto & Lee that are designated as Endangered, Near Threatened, and Vulnerable (Korean Red List) have been found to inhabitthe Taean area. Also, two species belonging to the exportable species group (Ceriagrion auranticum Fraser, Paracercion melanotum (Selys)) and one species belonging to the climate-sensitive biological indicator group (Ischnura elegans (Van der Linden)) were identified. In this study, four significant species including the Endangered are presented on the Korean distribution map based on the information in the national ecosystem survey accumulated for 7 years (2006-2012) by the Ministry of Environment.

Influences of Temperature and Density on the Feeding Growth, and Blind-side Malpigmentation of Fry Starry Flounder Platichthys stellatus (강도다리(Platichthys stellatus) 치어의 섭식, 성장 및 흑화 발현에 있어 온도와 밀도의 영향)

  • Kang, Duk-Young;Kim, Won-Jin;Kim, Hyo-Chan;Chang, Young Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.5
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    • pp.588-596
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    • 2014
  • To examine the influences of water temperature and stocking density on feeding, growth and blind-side hypermelanosis of the starry flounder Platichthys stellatus, we performed an experiment with fry at two densities: 2 and 8 fish/L. The fry had a total length of $3.2{\pm}0.1cm$, body weight $0.6{\pm}0.1g$, and pigmented patches (pigmented ratio $2.6{\pm}0.4%$) on the blind side. Duplicate experiments were conducted in 93.7 L glass tanks for 120 days, from July to November. We determined daily food intake (DFI), food efficiency (FE), growth, survival rate, ratio of hypermelanic fish, and pigmented area rate on the blind side at 60-day intervals. The DFI was less than 50 mg/fish/day, and growth was delayed from July to September (water temperature [WT]> $20^{\circ}C$). After October, when WT < $20^{\circ}C$, the DFI increased significantly and the growth was accelerated, suggesting that the rearing temperature of starry flounder in artificial facilities should be < $20^{\circ}C$. While the FE, and survival did no differ between the two density groups, DFI and growth were significantly higher at 2 fish/L than at 8 fish/L. There was no difference in the pigmented area ratio between the two density groups. Although the hypermelanosis was not correlated with body size, the malpigmentation increased with growth. These results suggest that a high stocking density is not the main cause of blind-side hypermelanosis, although it can accelerate hypermelanosis in the starry flounder.

Response of Soil Mesofauna and Ground-dwelling Arthropods to Plant Communities in a Mountain Pasture (산지초지의 식물 군락에 따른 토양 미소동물 및 지표면 서식 절지동물의 군집 차이)

  • Eo, Jinu;Kim, Myung-Hyun;Kwon, Soon-Ik;Song, Young-Ju
    • Korean Journal of Environmental Biology
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    • v.34 no.4
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    • pp.233-239
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    • 2016
  • The purpose of this study is to investigate the response of the soil mesofauna and ground-dwelling arthropods to vegetation structure and composition in a mountain pasture. The pasture mainly comprised five types of plant communities; Agrostis alba - Phleum pratense community, Poa pratensis community, Festuca ovina community, Rumex acetosella community, and the shrub assemblage comprised Spiraea miyabei-Spiraea salicifolia community. Soil chemical properties including the pH, EC and nutrient levels were influenced by plant communities. Plant-specific responses were observed for bacteria-feeding and plant-feeding soil nematodes. Collembola and Oribatida having the same feeding habit were influenced differently by plants. nMDS showed that the community of ground-dwelling arthropods were separated by vegetation types. Species numbers of arthropods were different among different plant communities. Our results indicate that vegetation structure and composition can influence both abundance of diversity of terrestrial fauna.

Stomach Contents of the Manchurian Trout (Brachymystax lenok tsinlingensis) and River Salmon (Oncorhynchus masou masou) in the Odae Mountain (오대산 일대에 서식하는 열목어와 산천어의 식성)

  • Yoon, Hee-Nam;Kim, Ki-Dong;Jeon, Yong-Lak;Lee, Jung-Hyo;Park, Young-Jun
    • Korean Journal of Ichthyology
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    • v.25 no.2
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    • pp.90-105
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    • 2013
  • This study was performed to find out stomach contents of cold water fish such as Manchurian trout (Brachymystax lenok tsinlingensis) and River salmon (Oncorhynchus masou masou) in the Odae mountain area. Field survey was carried out 3 times by each season from May to October 2012 along the Gyebang stream and the Yangyang-Namdae stream at north-west mountain slope and north-east mountain slope of the Odae mountain area respectively. The result of digestive track analysis showed that food species of Manchurian trout were total individuals of 645 including 5 orders, 23 families, 39 species of benthic macroinvertebrates and 11 taxa of terrestial insects. And each IRI (Index of Relative Importance, %) value of food species by Manchurian trout was terrestial insects 37.0%, Trichoptera 36.4%, Ephemeroptera 20.0%, Diptera 3.9%, Plecoptera 2.7%, and Gordea <0.1%. While the River salmon fed on 1,186 individuals covering 4 orders, 20 families, 33 species of benthic macroinvertebrates and 6 taxa of terrestial insects including arachnid. Also IRI values by River salmon were terrestial insects including arachnid 2.7%, Ephemeroptera 52.9%, Trichoptera 27.9%, Diptera 9.4%, and Plecoptera 7.0% respectively. With these results, we might say that both Manchurian trout and River salmon is carnivorous fish which display the feeding preference to terrestial insects and benthic macroinvertebrates. As a results we could find out that the two kinds of cold water fish preferred similar habitat types and liked same order of food species in same season, however the compositions of food species for Manchurian trout and River salmon were considerably different.

Effect of Supplementary Feeding Levels on Productivity and Grazing Intensity in Grazing Elk stags(Cervus canadensis) (보충사료 급여수준이 엘크 수사슴의 생산성 및 방목강도에 미치는 영향)

  • Lee, Jinwook;Lee, Sang Hoon;Lee, Sung Soo;Jeon, Dayeon;Kim, Sung Woo;Yun, Yeong Sik;Kim, Sang Woo;Park, Hyung Soo;Kim, Kwan Woo
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.2
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    • pp.61-67
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    • 2019
  • This study was conducted to investigate the effect of supplementary feeding levels on livestck and forage productivity and grazing intensity in Elk stags (Cervus canadensis). A fifteen 2-year-old Elk stags about 195 kg were randomly assigned to one of three dietary treatments (five animals per treatment). The dietary treatments consisted of a feeding concentrate of 1.0% of body weight (T1), 1.5% of body weight (T2) and 2.0% of body weight. Total dry matter intake (TDMI) was increased with increased with an increasing supplementary feeding levels. Average daily gain (ADG) were significantly increased with an increasing supplementary feeding levels (p<0.05) and reached a maximum on July and was lower in spring than autumn. The velvet antler production was no differences among treatment groups. Forage productivity of pasture and crude protein content were highest on May and decreased thereafter, however, crude fiber content was the reversed. The grazing intensity of Elk stags was increased in spring (38 to 59 head per ha) than summer and autumn (13 to 32 head per ha). The average grazing intensity of Elk stags ranged from 21 to 34 head per ha, which is affected by supplementary feeding levels. This result suggests that feeding supplementary diet at 1.5 % of body weight was needed to maintain the stable wight gain in antler growing periods and control the proper grazing intensity of Elk deer stags.

Spatial Analysis of Ecological Characteristics for Benthic Macroinvertebrate Community Structure in Lake Hoengseong Region (횡성호 일대 저서성 대형무척추동물 군집구조의 생태적 특성 분석)

  • Lee, Hwang-Goo;Jung, Sang-Woo;Choi, Jun-Kil
    • Korean Journal of Environment and Ecology
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    • v.26 no.1
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    • pp.46-56
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    • 2012
  • Benthic macroinvertebrates were investigated in Hoeongseong Lake region from March to October 2010, Korea. Macroinvertebrate communities, composition of the functional feeding groups, habitiat oriented groups and the biological water quality were assessed above and below Hoeongseong Dam in the lake region. Six sites, two (St.1~2) above the lake, two (St. 3~4) into the lake, and two (St. 5~6) below the dam, were selected for quantitative (Surber sampler $30cm{\times}30cm$, mesh size 0.2 mm) and qualitative (Hand net) samplings of benthic macroinvertebrates. As a result, a total of 83 species belonging to 43 families, 17 orders, 8 classes, and 5 phyla were recognized. The EPT-group (50 spp. : 60.24%) that is major taxa or EPT-group plus Diptera (61 spp. : 73.49%) occupied most of benthic macroinvertebrates community. Based on quantitative sampling, the number of benthic maroinvertebrates above the lake was 2,399 individuals including 54 species, 28 families, 11 orders, 4 classes, and 4 phyla, whereas 510 individuals including 16 species, 12 families, 7 orders, 4 classes, and 3 phyla in the lake and 626 individuals including 62 species, 33 families, 13 orders, 6 classes, and 4 phyla below the dam were collected respectively. Dominance index was the highest, with 0.82-0.93 ($0.87{\pm}0.05$) in Hoeongseong lake (St. 3-4), diversity index was 3.04-3.16 ($3.10{\pm}0.06$), evenness index was 0.79-0.85 ($0.82{\pm}0.03$), and richness index was 7.27-8.52 ($7.90{\pm}0.63$), which were relatively higher below the dam sites. In the functional feeding groups, collector-gatherers and collector-filterers were the highest in the whole sites, and predators (Micronecta sedula) was appeared highly in the lake. Moreover, swimmers, burrowers, and clingers were considerably occupied in all collecting sites. The result of the DCA, similarity analysis, and MRPP were well reflective of the composition of lake and stream macroinvertebrates. ESB indicate that the lake sites were evaluated heavily polluted under priority improvement waters. Also, Semisulcospira gottschei, Ecdyonurus kibunensis, Epeorus pellucidus, Rhoenanthus coreanus, Stenelmis sp., and Cheumatopsyche brevilineata are considered as an indicator species above and below Hoeongseong Lake, whereas Macrobrachium nipponense and Micronecta sedula are indicated in the lake.

Leaf Litter Breakdown of Quercus mongolica and Calpinus cordata In a Headwater Stream (소하천의 신갈나무와 까치박달 낙엽의 분쇄)

  • Chung, Keun
    • Korean journal of applied entomology
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    • v.40 no.1
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    • pp.23-30
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    • 2001
  • Leaf Litter processing rate of Quercus mongolica was compared with that of Carpinus cordata in a first-order stream draining Mt. Jumbong in Inje-Gun, Kangwon Province. Daily processing rate (-k . day$^{-1}$ ) of Q. mongolica leaf litter in mesh bags was 0.00503, about one-third of that of C. cordata leaf litter. Forty five macroinvertebrate taxa were collected from litter bags; 39 taxi from C. cordate and 38 taxa from Q. mongolica litter bags. Nemoura tau, a precopteran shredder, was the most abundant taxon in both leaf species, and the second was the non-predatory chironomids. In terms of biomass, Gammarus, an amphipodan shredder, was the largest. and followed by Cincticostella castanea, an ephemeropteran gatherers. The biomass of most insect taxa decreased during April to June, while that of non-insect taxa greatly increased during the same time period. Gammarus was the most important shredder talon to the leaf litter breakdown in the experimental stream and appeared to prefer C. cordata to Q. nongolica leaf litter. N. tau, in spite of its abundance, seemed to have a limited effect on the leaf litter processing . Since other shredders were minor compared with these two taxa, leaf litter processing in this stream appeared to largely depend on the feeding ecology of Gammarus.

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The past, present and future of silkworm as a natural health food (천연 건강식품인 누에의 과거, 현재 그리고 미래)

  • Kim, Kee-Young;Koh, Young Ho
    • Food Science and Industry
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    • v.55 no.2
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    • pp.154-165
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    • 2022
  • Humans have been breeding the mulberry silkworm for the long period of time to obtain silk fabric and nutrient-rich pupae. Currently, silkworm larvae, pupae, and silk-Fibroin hydrolysates are registered as food raw materials, while silkworm feces and Bombyx batryticatus are registered as Korean traditional medicines. Among sericulture products, individually recognized health functional food ingredients include silk-protein acid-hydrolysates for immunity enhancement, Fibroin-hydrolysates for memory improvement, and freeze-dried 5th instar and 3rd-day-silkworm powder for lowering-blood sugar. Recently, HongJam produced by steaming and freeze-drying mature silkworms were reported to have various health-promoting effects such as preventing the onset of Alzheimer's disease and Parkinson's disease, enhancing gastro-intestinal functions, improving skin-whitening and hair growth, and extending healthspan. By consuming silkworm products with various health-promoting effects, it is possible to increase the healthspan of human beings, thereby reducing personal and national medical expenses, resulting in increasing the individual's happiness.

Diversity of Benthic Macroinvertebrate Community in Sohan Stream in Ecological Landscape Conservation Area (생태·경관보전지역인 소한계곡의 저서성대형무척추동물 다양성 분석)

  • Ham, Seong-nam;Kim, Sun-yu;Joo, Jaehyung;Jang, Seuk Gu;Kim, Dongsam;Bae, Mi-Jung
    • Korean Journal of Ecology and Environment
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    • v.54 no.4
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    • pp.374-383
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    • 2021
  • In 2020, the diversity of benthic macroinvertebrate communities was investigated in the Sohan stream, an ecological and landscape conservation area, and the results were compared with the previous research conducted in 2011. In total, 42 species (two phyla, three classes, and seven orders) were found in the Sohan stream. Species richness and abundance sharply decreased at all sampling sites because of Typhoons Haishen and Maysak in 2020, which had a direct impact on the stream. In the functional feeding group, the ratio of collector-gatherers was the highest at all sampling sites. However, during the autumn season, the shredder ratio increased from 13.4% to 42.4% in the uppermost stream site. Compared with the diversity of benthic macroinvertebrates surveyed in 2011, a total of 53 species (two phyla, three classes, and eight orders) were found. The percentage of species richness and abundance of Ephemeroptera, Plecoptera, and Trichoptera was more than 50% both in 2011 and 2020. Only the richness of Ephemeroptera was significantly different between them (2011: 2.9 and 2020: 6.7). In this study, the abrupt changes of species richness and abundance in benthic macroinvertebrate were not observed before and after the designation of an ecological and landscape conservation area. However, it is necessary to monitor benthic macroinvertebrates in order to confirm that biodiversity is continuously maintained long after the designation of the ecological and landscape conservation area.

Egg Development and Morphological Change of Larvae and Juveniles of the Starry Flounder, Platichthys stellatus (강도다리, Platichthys stellatus의 난발생과 자치어의 형태발달)

  • Byun, Soon-Gyu;Lee, Bae-Ik;Lee, Jong-Ha;Ku, Hak-Dong;Park, Sang-Un;Yun, Seong-Min;Hwang, Seon-Young;Kim, Yi-Cheong;Han, Hyung-Gyun
    • Korean Journal of Ichthyology
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    • v.19 no.4
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    • pp.350-359
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    • 2007
  • The egg development and morphological change of larvae and juveniles of the starry flounder, Platichthys stellatus were observed in laboratory. Fertilized eggs of the species, 1.09~1.19 mm (mean $1.13{\pm}0.03mm$, n=50) in diameter, were floating, colorless, transparent in shape and lacked in oil globules. The eggs hatched out 121 hours after fertilization at water temperature $8.2{\sim}11.2^{\circ}C$. The size of the hatched larvae were 2.58~2.89 mm (mean $2.67{\pm}0.09mm$) in total length, their mouth and anus were not open yet and myotome number was 14+27=41. Melanophore and xanthophore appeared on the notochord and digestive organ and the margin of membrane fin, on the yolk sac and eyes were lacking in pigment cells. 5 days after hatching the larvae attained 4.30~4.97 mm (mean$4.74{\pm}0.21mm$) in TL, and their mouth and anus were open. 10 days after hatching the larvae transformed to postlarval stage and they were 4.67~5.75 mm in TL (mean $5.30{\pm}0.31mm$), and absorbing the yolk completely. Feeding activity increased as the mouth became larger. At 23 days, the larvae attained 6.69~8.82 mm in TL (mean $7.85{\pm}0.75mm$), and the right eye was started moving to the left side of the head. At 52 days, the juveniles attained 10.99~17.06 mm in TL (mean $13.50{\pm}1.67mm$). The right eye was moved completely onto the left side. All of the fins had completed set of the fin rays (D. 64~67: A. 45~51: P. 11: V. 6: C. 19).