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The Ichthyofauna and Community Structure of Fish at Wondong Marsh in the Kyeongnam Province, Korea (원동습지의 어류상과 군집구조)

  • Yang, Hong-Jun;Kum, Ji-Don;Lee, Yong-Ho
    • Korean Journal of Ichthyology
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    • v.13 no.4
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    • pp.261-266
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    • 2001
  • The ichthyofauna and the structure of fish community were surveyed from June to August in 2000 at four stations of the Wondong marsh, Yangsan city in Kyungnam province. During the study period, 24 species belonging to eight families were collected. Cyprinid fish occupied 62.5% (15 species) and cobitid and centrarchid fish 8.3% (each 2 species). According to relative abundance in the whole marsh, Z. platypus (23.2%) was dominant species and S. gracilis majimae (14.2%) was subdominant species. M. salmoides (9.6%), C. auratus (8.3%), P. herzi (8.3%), M. yaluensis (6.5%), M. anguillicaudatus (4.0%), L. macrochirus (3.4%), P. parva (2.8%), R. ocellatus (2.5%), C. brevicauda (2.5%), C. sinensis (2.5%) and O. platycephala (2.2%) were common species and C. carpio, A. rhombeus, H. labeo, S. variegatus wakiyae, S. chankaensis tsuchigae, Z. temmincki, O. bidens, S. asotus, C. herzi, R. brunneus, C. argus were rare specieswhich occupied less than 2.0% in relative abundance. Six species of S. variegatus wakiyae, S. chankaensis tsuchigae, S. gracilis majimae, M. yaluensis, C. herzi and O. platycephala in observed species were known as endemic species. By analyzing of fish community in the surveyed area, the species diversity and evenness of the fishes were high but dominance was low. And the similarity of the fish species among the sites was mid-grade as more than 0.55 in index.

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Variation of Grain Quality of Rice Varieties Grown at Different Locations II. Relationship between Characteristics Related to Grain Quality (벼품종의 재배지역에 따른 미질특성변이 II. 미질관련형질 상호간의 관계)

  • Kwang-Ho Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.2
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    • pp.137-145
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    • 1990
  • Six commercial rice varieties were cultivated at different locations in 1987 and 1988. Rice samples harvested from 8 to 20 locations for a variety each year were used to measure or observe grain appearance, amylose content and alkali digestibility, cooked rice texture using rheometer, gelatinization and viscosity of rice flour using amylograph, and eating Quality of cooked rice by sensory evaluation. Relationship between Quality characteristics showing large locational variation were analized to approach the long-term objective, rice grain Quality standardization. Percent white-center and white-belly grain of the same variety showed great variation between locations, but did not affect on 1000-grain weight, amylose content and alkali digestibility, amylogram and rheogram characteristics, and eating Quality of cooked rice. Positive correlationship were obtained between maximum viscosity and break down, and maximum viscosity and alkali digestibility. Set back was correlated negatively with maximum viscosity, break down and alkali digestibility. Rice samples having significantly lower values of maximum viscosity and break down and higher set back value at the same time showed higher ADV and lower texture palatability index (TPI) and viscousness/hardness ratio (Vi/H), and lower sensory evaluation score of cooked rice compared with those of rices having typically higher values of maximum viscosity and break down and lower set back value. When TPI, Vi/H and overall sensory eating score of cooked rices measured were divided into three categories, high, medium and low using deviation from locational mean value of a variety, many of rice samples having high TPI or high Vi/H showed medium or high in overall sensory eating score of cooked rice.

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A Study on Factors Affecting Reemployment of the Disabled Workers owing to Industrial Injury in Korea (산재장애인의 재취업실태와 영향요인 분석)

  • Park, Soo-Kyeong
    • Korean Journal of Social Welfare
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    • v.37
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    • pp.171-193
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    • 1999
  • The ultimate goal of rehabilitation is social integration. Reemployment is, for the disabled workers, the primary source of not only income, but also identity and interaction. Unfortunately, for most disabled workers employment represents only a yet-to-be-fulfilled hope, a close but inaccessible goal, a daily reminder that they are not among the majority. The purpose of this study is to estimate reemployment rate in the industrial injured and to find factors affecting reemployment of disabled workers owing to industrial injury, and to make policy implication for the better industrial injury compensation rehabilitation system. The data were obtained through telephone interview with disabled worker who completed work injury compensation process in 1996-1997. The final sample was consisted of 1,060 respondents. The major findings were that almost lout of 3 disabled worker returned to work, and that the factor affecting reemployment of the disabled workers were severity injury, ADL(activity of Daily Living), the perception of disability severity, controlling for the demographic factors such as sex, age, education, marital status. The results indicated that psychosocial factors as well as physical function had influces on returning to work. The current findings suggests that rehabilitation services and policy aimed at enhancing vocational rehabilitation program and rehabilitation engineering services, and improving psychosocial resources should be considered by rehabilitation professionals and policy makers.

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Study on the Evaluation of Ecological Health by using Fish Communities in the Wonju Stream, Korea (원주천의 어류군집을 이용한 생태적 건강성 평가 연구)

  • Park, Hyun Kyung;Choi, Jun Kil;Won, Kyung Ho;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.684-693
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    • 2017
  • The purpose of this study was to analyze fish communities in the Wonju stream located in Wonju-si in Gangwon-do, and to evaluate the health of the stream through past and present changes. We performed investigations four times from May 2015 to September 2016. In the survey, 5,201 individuals which belonged to 27 species and 9 families were collected. Zacco platypus was the dominant species and Pungtungia herziwas the subdominant species. Eight Korean endemic species (Acanthorhodeus gracilis, Zacco koreanus, Coreoleuciscus splendidus, Squalidus gracilis majimae, Microphysogobio yaluensis, Iksookimia koreensis, Koreocobitis rotundicaudata, Coreoperca herzi) were observed and showed a ratio of 16.54%. The fish community of dominance ($0.72{\pm}0.10$), diversity ($1.37{\pm}0.32$), evenness ($0.61{\pm}0.13$), and richness ($1.70{\pm}0.23$) were evaluated. According to our analysis of tolerance guilds, the total individual number of intermediate species was higher than the sensitive and tolerant species. As a result of the trophic guild analysis,the omnivore and insectivore species were relatively high. The value of the qualitative habitat evaluation index (QHEI) in the wonju stream was averaged 121.2 (${\pm}23.4$), indicating a suboptimal condition. Stream health showed that the fish assessment index (FAI) value was an A to C grade in the Wonju stream. A correlation coefficient analysis with FAI and various factors was analysed statistically, and had a high correlation in QHEI, with the omnivore species, insectivore species, intermediate species, sensitive species, dominance, diversity, evenness, and richness.

Fish Community Characteristics in Hwapocheon Wetland, Korea (화포천 습지의 어류군집 특성)

  • Ko, Myeong-Hun;Choi, Kwang-Seek;Lim, Jeong-Cheol
    • Korean Journal of Environment and Ecology
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    • v.36 no.2
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    • pp.165-176
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    • 2022
  • This study surveyed the characteristics of fish communities in Hwapocheon Wetland, Korea, from May to September 2020. The survey collected 735 objects in 21 species belonging to 7 families from 8 survey stations. The dominant and subdominant species were Hemiculter eigenmanni(23.8%) and Micropterus salmoides(10.3%), respectively. The next most abundant species were Zacco platypus(9.5%), Carassius auratus(9.4%), Pseudorasbora parva(9.0%), Squalidus chankaensis tsuchigae(6.7%), Acheilognathus macropterus(5.4%), Lepomis macrochirus(5.2%), Pseudogobio esocinus(4.1%), Opsariichthys uncirostris amurensis(3.7%), and Carassius cuvieri(3.3%). Among the fish species collected, one species, Culter brevicauda, was class II endangered wildlife designated by the Ministry of Environment, and one species,S. c. tsuchigae(4.8%), was endemic to Korea.Additionally, three exotic species (M. salmoides, L. macrochirus, and C. cuvieri) and one landlocked species (Rhinogobius brunneus) were collected. Compared to previous studies, the proportion of fish living in the running water area tended to decrease, the proportion of fish living in the water purification area tended to increase, and ecosystem-disturbing species (M. salmoides and L. macrochirus) tended to increase gradually. Results of fish community analysis showed that the mainstream stations (St. 1, 3, 4, 5, 6, and 8) had low dominance, but high diversity and richness, and other stations (St. 2 and 7) had high dominance but low diversity and richness. The river health (index of biological integrity) evaluated using fish was assessed as bad (6 stations), normal (1 station), and very bad (1 station). The water quality grade was assessed as slightly bad due to the chemical oxygen demand (COD), total organic content (TOC), suspended solid (SS), and total coliforms (TC). The annual water quality showed a gradually increasing trend of biological oxygen demand (BOD), COD, SS, and chlorophyll-a. The stable life of fish and the improvement of river health in Hwapocheon Wetland require water quality improvement and the systematic management of ecosystem-disturbing species (M. salmoidesand L. macrochirus).

Community Characteristics of Benthic Macroinvertebrate before the Translocation Project of Songchu Valley in Mt. Bukhansan (북한산 송추계곡 이주사업 이전 저서성 대형무척추동물 군집 특성)

  • Wang, Ju-hyoun;Lee, Hwang-Goo;Choi, Jun-Kil
    • Korean Journal of Environment and Ecology
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    • v.30 no.1
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    • pp.81-91
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    • 2016
  • This study was performed to investigate and monitor changes in aquatic ecological communities, particularly benthic macroinvertebrates from the upper reaches to the down reaches of Songchu valley before the project of Songchu valley translocation initiates. We aimed to verify the translocation effects of the valley on the aquatic macroinvertebrate communities. A field investigation was conducted over three rounds from November 2012 to August 2013. A total of four sites were selected: one to represent the control site (St. 1), two for the translocation sites (St. 2, 3), and one for the downstream sites (St. 4). Our quantitative sampling revealed that the total number of benthic macroinvertebrates were 3,805, which belong to 62 species, 32 families, 9 orders, 5 classes and 4 phyla. As a result of the community analysis at the control site, dominant index was 0.52(${\pm}0.16$), diversity index was 1.95(${\pm}0.44$), evenness index was 0.81(${\pm}0.04$), and richness index was 2.25(${\pm}0.85$). Thus, the community structure was found to be relatively stable. For the EPT ratio of species and individuals that appeared, the control site showed the highest values at 67.60(${\pm}5.66$)% and 66.30(${\pm}2.06$)% respectively, but its value became lower towards the downstream sites. Upon the statistical analysis of the functional feeding groups, it was found that gathering-collectors and filtering-collectors increased toward the downstream sites while shredders decreased. From the point of habitat-oriented group evaluation, sprawlers decreased and burrows increased toward the downstream sites. According to the analysis using Korea Saprobic Index (KSI), the control site is categorized as grade A with average value at 0.75(${\pm}0.10$). However, the grade gradually falls from A to B toward the lower reaches, as the KSI value increases at the translocation and downstream sites.

Preliminary Environmental Impact Assessments on Fish Compositions and the Ecological Health of Jeokbyeok River on the Road Construction of Muju-Geumsan Region (무주-금산간 도로건설에 따른 적벽강의 어류 종 조성 분석 및 생태건강도 사전환경성평가)

  • Lee, Sang-Jae;Park, Hee-Sung;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.26 no.1
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    • pp.27-43
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    • 2017
  • The objectives of the study were to evaluate fish compositions, endangered species, community structure, physical habitat, and general water quality for a preliminary environmental impact assessment of Jeokbyeok River on the road construction between two regions. Total number of species and total number of individuals, based on CPUE, were 23 and 1186, respectively. The endangered species (I, II) as the legal protection species were Pseudopungtungia nigra (79 samples) Gobiobotia brevibarba) (5) Gobiobotia macrocephala (2), indicating a requiring of endangered species conservation. In the meantime, exotic species and ecological disturbing species such as Micropterus salmoides and Lepomis macrochirus, were not present, indicating a well conserved area. According to fish community analysis, values of species diversity index were high (range: 0.788 - 1.030), and the dominance index were low (range: 0.097 - 0.183), indicating that the fish community in this area was maintained well without high dominacne by specific species. Also, fish analysis on tolerance guilds and trophic guilds showed that the proportions of sensitive species were largely exceeded the proportions of the tolerant species, while the proportions of insectivore species were largely exceeded the proportions of the omnivore species. This outcome suggests that the ecosystem was well maintained in terms of tolerance and trophic compositions (food chain). Ecological health, based on the multi-metric fish model of Fish Assessment Integrity (FAI), reflected those fish conditions. In other words, values of FAI model averaged 82.4, which means a "good condition" in the criteria of ecological health by the Minstry of Environment, Korea. In addition, general water quality and physical habitat analyses showed that the system was in good condition. Under these conditions, if the road constructions between the two regions happen in the future, inorganic suspended solids may increase in the waterbody, and this may result in indirect or direct influences on the physical habitats and food chain as well as fish compositions, so the ecological protections and prevention strategy from the soil erosion are required in the system.

Ecological health assessments using fish communities in the habitat of Manchurian trout (열목어 서식지의 어류군집을 이용한 생태적 건강성 평가)

  • Ko, Min Seop;Choi, Jun Kil;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.652-663
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    • 2019
  • The purpose of this study was to conduct ecological health assessments by using the fish communities in the Manchurian trout habitat. Sampling was conducted twice in July and September 2018. In the survey, 1,119 individuals belonging to 16 species and seven families were collected. The dominant species by number was Rhynchocypris kumgangensis and the subdominant species was Zacco koreanus. Korean endemic species represented 73.33% at Geybang Stream and 76.92% at Naerin Stream. Community analysis revealed that the structure of the fish community was unstable by the dominance index 0.63 (±0.09)-0.97 (±0.01), the diversity index 1.63 (±0.23)-0.33 (±0.09), the evenness index 0.79 (±0.06)-0.24 (±0.07) and the richness index 0.67 (±0.14)-1.80(±0.16). According to the analysis of the tolerance guilds, the total individual number of sensitive species was higher than the intermediate and tolerant species. The insectivore species accounted for 65.09-98.56% of the total trophic guilds, which was the highest observed. The value of the QHEI (Qualitative habitat evaluation index) in the Brachymystax lenok tsinlingensis habitat was 119.5 (±0.5)-153.5 (±0.5), indicating an optimal-suboptimal condition. The FAI (Fish assessment index) stream health value was A to B in the study sites. Correlation analysis with FAI and various factors was conducted and a high correlation in QHEI, Brachymystax lenok tsinlingensis individuals, species, individuals, diversity, richness, sensitive species, carnivorous species, insectivorous species, and omnivorous species was found. The similarity analysis was divided into three groups from A to C, based on 56.9%.

Biodiversity and Characteristic Communities Structure of Freshwater Ecosystems in the Western Area of DMZ, Korea (민통선이북지역(DMZ) 서부평야 일대의 수생태계 생물다양성 및 군집 특성)

  • Jung, Sang-Woo;Kim, Yoon-Ho;Kim, Hyun-Mac;Kim, Su-Hwan
    • Korean Journal of Environment and Ecology
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    • v.32 no.6
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    • pp.603-617
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    • 2018
  • This study surveyed the diversity and community characteristics of benthic macroinvertebrates and freshwater fish, which are the main animal classifications in a hydro ecosystem, from May to September 2017 in the western plains of the Demilitarized Zone (DMZ). The results showed a total of 125 species of benthic macroinvertebrates belonging to 66 families, 19 orders, and four phyla in the streams and wetlands. Among benthic macroinvertebrates, Coleoptera (27 spp.: 21.60%) was the largest group in terms of species richness followed by Odonata (26 spp.: 20.80%), non-Insecta (22 spp.: 17.60%), and Hemiptera (11 spp.: 8.80%) occupying in the lentic area. Of the feeding function groups (FFGs), predators (51 spp.: 56.67%) showed a relatively larger presence, indicating the dominance of hygrophilous invertebrates that usually inhabit the freshwater wetlands or ponds. Of the habitat oriented groups (HOGs), climbers (33 spp.: 24.44%) and burrowers (17 spp.: 12.59%) were the dominant groups. This observation is typical in a slow flowing habitat and can lead to the disturbance of the ecosystem due to cannibalism among predators. Cannibalism can be caused by stress induced by various population and environmental factors. For the ecosystem services benchmark (ESB) value, site 13 appeared to be the highest with 82 marks while other sites showed relatively lower rates and indices (III water quality class with ${\alpha}$-mesosaprobic). The analysis result of stability factors showed that almost all sites were evaluated to be the I characteristic group with high resilience and resistance or the III characteristic group that was sensitive to environmental disturbance and formed uneven and unstable communities. Of the freshwater fishes, 46 species (3,405 individuals) belonging to 39 families and 18 orders were identified in all the investigated sites. Among them, Cyprinidae (30 spp.: 65.2%) was the largest group, and Zacco koreanus was identified as the dominant species (728 individuals, 21.4%). The survey of freshwater fish communities found both stable communities (sites 7 and 13) with low dominant index (0.39) and high diversity index (2.29) and unstable communities (sites 2, 3, 8, and 10) in opposite tendency. This survey found five Korean endemic species, 17 species belonging to the export controlled species, two endangered species level II (Lethocerus deyrollei and Cybister chinensis), and rare species (Dytiscus marginalis czerskii) among benthic macroinvertebrates. The survey also found an invasive species, Ampullarius insularus, which was distributed throughout the whole area and thus can continuously disturb the ecosystem in the western plain area in the DMZ. Of freshwater fish, one natural monument (Hemibarbus mylodon) and three endangered species level II (Acheilognathus signifer, Gobiobotia macrocephalus, and G. brevibarba) were observed. The survey also found four introduced species (Pomacea canaliculate, Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides) in the western DMZ area, indicating the need for the protection and conservation measures.

Isolation and Physicochemical Properties of Rice Starch from Rice Flour using Protease (단백질분해효소에 의한 쌀가루로부터 쌀전분의 분리 및 물리화학적 특성)

  • Kim, ReeJae;Oh, Jiwon;Kim, Hyun-Seok
    • Food Engineering Progress
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    • v.23 no.3
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    • pp.193-199
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    • 2019
  • This study aimed to investigate the impact of protease treatments on the yield of rice starch (RST) from frozen rice flours, and to compare the physicochemical properties of RST by alkaline steeping (control) and enzymatic isolation (E-RST) methods. Although the yield of E-RST, prepared according to conditions designed by the modified 23 complete factorial design, was lower than the control, the opposite trends were observed in its purity. E-RST (RST1, isolated for 8 h at 15℃ with 0.5% protease; RST2, isolated for 24 h at 15℃ with 1.5% protease; RST3, isolated for 24 h at 15℃ with 0.5% protease) with the yields above 50% were selected. Amylose contents did not significantly differ for the control and RST2. Relative to the control, solubilities were higher for all E-RST, but swelling power did not significantly differ for E-RST except for RST1. Although all E-RST revealed higher gelatinization temperatures than the control, the reversed trends were found in the gelatinization enthalpy. The pasting viscosities of all E-RST were lower than those of the control. Consequently, the enzymatic isolation method using protease would be a more time-saving and eco-friendly way of preparing RST than the alkaline steeping method, even though its characteristics are different.