• Title/Summary/Keyword: 저서환경

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Biogeochemical Studies on Tidal Flats in the Kyunggi Bay: Introduction (경기만 부근 갯벌의 생지화학적 연구: 서문)

  • Cho, B.C.;Choi, J.K.;Lee, T.S.;An, S.;Hyun, J.H.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.1-7
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    • 2005
  • Tidal flats have been regarded to carry out transformation and removal of land-derived organic matter, and this purifying capability of organic matter by tidal flats is one of very important reasons for their conservation. However, integral biogeochemical studies on production and decomposition of organic matter by benthic microbes in tidal flats have been absent in Korea, although the information is indispensable to quantification of the purifying capability. Our major goals in this multidisciplinary research were to understand major biogeochemical processes and rates mediated by diverse groups of microbes dominating material cycles in the tidal flats, and to assess the contribution of benthic microbes to removal of organic matter and nutrients in the tidal flats. Our study sites were Ganghwa and Incheon north-port tidal flats that had been regarded as naturally well reserved and organically polluted, respectively. Our research group measured over 3 years primary production, biomass and community structure of primary producers, abundance and production of bacteria, enzyme activities, distribution of protozoa and protozoan grazing rates, rates of denitrification and sulfate reduction, early sediment diagenesis, primary production and respiration based on oxygen microelectrode. We analyzed major features of each biogeochemical process and their interactions. The results are compiled in the following articles in this special issue: An (2005), Hwang and Cho (2005), Mok et at. (2005), Na and Lee (2005), Yang et at. (2005), and Yoo and Choi (2005).

Characteristics of Recent Foraminifera and Surface Sediments in Gomso- Bay Tidal Flat, West Coast of Korea: Potential for Paleoenvironmental Interpretations (곰소만 조간대의 현생 유공충과 표층 최적물의 특성: 고환경 해석에 적용 가능성)

  • 우한준;장진호
    • 한국해양학회지
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    • v.30 no.3
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    • pp.184-196
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    • 1995
  • The line-SW is located in the mouth of Gomso Bay (20 Km long and 5-8 Km wide),west coast of Korea. This area is composed of sand flat, mud flat, sand shoal and chenier, The difference of physical, geological and geomorphic conditions in subenvironments of the bay may control and produce distingtive foraminiferal populations and assemblages. This study investigates whether five a priori subenvironments (five local zonations) in Gomso-Bay tidal flat can be distinguished from each other on the basis of total (living plus dead) foraminiferal assemblages. Seventy-four species (67 benthic; 7 planktonic) were recorded in total assemblages of surface sediments from 10 stations. Ammonia beccarii tepida, Discorbis candeiana, Elphidium etigoense and Eponides nipponicus were most dominant species in living and total assemblages. The relative abundance (%) of living population was high at upper flat and decreased from upper to lower flat. The low percentages of living populations in middle to lower flat are probably influenced by the decreasing reproduction of foraminifera caused by high energy condition and addition of dead species from offshore. The occurence of planktonic foraminifera in middle to lower flat (5.3∼6.6%) indicates introduction of planktonic foraminifera from offshore by storm and/or tidal current. The relatively high numbers of species in lower middle to lower flat are probably caused by a mixing of faunas from these areas and offshore. The high numbers of total individuals per 50 ml of sediment in upper flat indicate that this area is a relatively stable environment where waves and currents are protected by the chenier. Five biofacies of the total foraminiferal assemblages were established on the basis of dominant species (those representing more than 20% of the total assemblages in any station) in the five a priori subenvironments recognized along the Line-SW transect in Gomso-Bay tidal flat. Five biofacies are potentially useful in paleoenvironmental interpretation in late Quaternary Gomso-Bay tidal deposits.

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Polychaete Feeding Guilds from the Continental Shelf Off the Southeastern Coast of Korea (한국(韓國) 동남해역(東南海域)에 분포(分布)하는 다모류(多毛類)의 식이조합(食餌組合))

  • Choi, Jin Woo;Koh, Chul Hwan
    • 한국해양학회지
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    • v.24 no.2
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    • pp.84-95
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    • 1989
  • The feeding guild classification proposed by Fauchald and Jumars (1979) and the relationship between this guild structure and the habitat environment were examined based on the quantitative polycheate samples collected on the continental shelf off the southeastern coast of Korea. Total 12 feeding guilds were found and the major feeding guilds of polychaetes were BSX (burrowing, sessile, non-jawed), SDT (surface deposit feeding, discretely motile, tentaculate), SST (surface deposit feeding, sessile, tentaculate), BMX (burrowing, motile, non-jawed), BMJ (burrowing, motile, jawed), SDJ (surface deposit feeding, discretely motile, jawed). There were more significant associations between feeding guilds and mean grain size (${\phi}$); SST and BMJ showed a positive correlation with mean phi, whereas CDJ (carnivore, discretely motile, jawed) and FDT (filter feeding, discretely motile, tentaculate), a negative value. The CDJ and CMX (carnivore, motile, non-jawed) guilds showed positive correlations with sand content, but only SST guild showed a positive correlation with clay. The heterogeneity of sediment or sorting value (${\phi}$) was highly associated with various feeding strategies of polychaetes. Surface deposit feeders and filter feeders, sessile, and tentaculate strategies were associated with poorly sorted or heterogeneous sediments. Some preliminary polychaete feeding surfaces were posed. Southern and northern coastal region composed of muddy sediment were characterized by SDJ; northern slope of mud by SST; central coast of mud by SDT, BSX; and BMX; southern offshore of sandy sediment by SDJ and IDT (interface feeding, discretely motile, tentaculate).

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Abundance and Biomass of Macroinvertebrate Association in a First Order Stream at Mt. Jumbong, Kangwon-do (점봉산의 한 일차하천에 서식하는 대형무척추동물의 풍부도와 현존량)

  • Chung, Keun
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.1-10
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    • 2005
  • Macroinvertebrates from a first order stream at Mt Jumbong, Kangwon-do, was examined for their abundance and biomass. Sampling was done by using a pipe sampler (${\phi}$ 20 cm) for 11occasions (n = 5) at 4${\sim}$6 weeks intervals during November 1997 through October 1998. Water temperature and electronic conductivity of the study stream ranged $0\;{\sim}\;14^{\circ}C$ and 15${\sim}$25 ${\mu}s$/cm, respectively. During the study, 53 insect taxa and 3 non-insect taxa were collected. Annual mean number of individuals (${\pm}$1 SD) was 77741${\pm}$69232${\cdot}$m$^{-2}$ ${\cdot}$yr$^{-1}$, being high in winter (${\pm}$1 SD) (December: 171178${\pm}$130468 $m^{-2}$) and low in summer (${\pm}$ 1 SD) (June: 29872${\pm}$13078 $m^{-2}$). Non-predatory subfamilies of Chironomidae and Nemoura sp. occupied 53.3% and 21.8% of annual abundance. Annual mean biomass was 10g${\cdot}$m$^{-2}$${\cdot}$yr$^{-1}$ in ash free dry weight (AFDW), being high in late winter (February: 16 gAFDW $m^{-2}$.) and low in summer (June: 3 gAFDW $m^{-2}$). Gammarus sp. represented 39.8% of the total biomass and was followed by non-predatory subfamilies of Chironomidae (15.2%) and Hydatohylax sp. (8.5%, Limnephilidae: Trichoptera). Since the non-predatory subfamilies of chironomidae were composed of many species, Nemoura sp. was the most abundant taxon. However, Cammarus sp. was surely the most important taxon to the functional aspects of this first order stream ecosystems.

Ecological Health Assessment Based on Fish Assemblages Along with Total Mercury Concentrations of Zacco platypus in Miho Stream (어류 군집을 이용한 미호천의 생태 건강성 평가 및 피라미(Zacco platypus)의 총수은 함량)

  • Lee, Jae-Hoon;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.288-297
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    • 2010
  • This study was to evaluate the ecological stream health through the Multimetric Fish Assessment Index (MFAI) along with fish fauna analysis based on the tolerance and trophic guilds at Miho stream in 2008 and 2009. Also, we analysed total mercury concentration in fish tissues to examine heavy metal contamination. Total sampled fish were 40 species and 2,557 individuals and Zacco platypus was the most dominant with 35% relative abundance. It was sampled with 11.4% RA for Korean endemic species (10 species 291 individuals) less than average RA 39.3% for the Geum river watersheds. According to the tolarance guild analysis, tolerant species was more dominant with 58.9% RA (15 species, 1,507 individuals) than sensitive species with 6.6% RA. Trophic guild analysis also suggested that omnivores were more dominant (60.5% RA) than insectivores (31.5% RA). Riffle-benthic species was also sampled with 7.7% RA. Ecological stream health based on the MFAI were averaged 25.3 (n=3) with fair-poor condition in 2008 and also 26.3 (n=3) with fair condition in 2009, just slightly increased than 2008. Qualitative habitat evaluation index was averaged 134 (n=3) with fair condition but most of sites had sediment accumulation that reflected substrate degradations proceeding. From the result of total mercury accumulation in fish tissues, kidney and liver tissues showed the highest but the lowest for gill tissues. Overall mercury concentration were not exceed the national standards by Korean Federation of Drug and Administration (KFDA). Consequently, our result could correspond with the characteristics of Miho stream where point sources such industrial complexes and wastewater treatment plant widely distributed around the stream along the gradient of up and downstream.

The study on Bi-Bak-Tam-Ra'Ja in Dokhaengpyun (동행편(獨行篇)에 나타난 비박탐나자(鄙薄貪懦者)에 대한 고찰(考察))

  • Yoon, Duk-Young;Ko, Byung-Hee
    • Journal of Sasang Constitutional Medicine
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    • v.8 no.1
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    • pp.57-74
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    • 1996
  • Donguisusaebowon, Kogchigo are wrritten by Dong-Mu. Dokhaengpyun of the Kogchigo has philosophy of Dong-Mu about Gi-In. In order to understand constitutional medicine of Dong-Mu, it is necessary to study about Bi-Bak-Tam-Ra'Ja(four types of man) in Dokhaengpyun. The results are summarized as follows : 1. In Dokhaengpyu, it is defined that In-Eui-Ye-JI - the nature of human - as In-Ja, Eui-Ja, Ye-Ja, Ji-Ja. This attribute is composed of Chung-Sin-Ip-Yong. We can know that this concept, that is Chung-Sin-Yeum-Hae'Ja, is relative to the Bi-Bak-Tam-Ra'Ja. 2. We can think and infer the relation of Sabujisim of Myeng-Ja and Bi-Bak-Tam-Ra'Ja from Bi-Bak-Tam-Ra'Bu that is attribute of In-Eui-Ye-ji'Ja. Bi-Bak-Tam-Ra'Ja can approach the behavior of Chung-Sin-Yeum-Hae'Ja, if they heard the attitude of YouHaHye and BaelYi which they have attribute of In-Eui-Ye-Ji'Ja. 3. They explain Tthat Bi-Bak-Tam-Ra-Jisim is quoted from SaBuJiSim of Dahak. Thinking that Bi-Bak-Tam-Ra-Jisim of Dokaengpyun and SaBujiSim of YuRiak, we know that there is no rule. So, it is difficult that we can infer the Simyok and make some pattern. 4. The relationship of Bi-Bak-Tam-Ra'Ja and In-Eui-Ye-Ji are different from the relationship of Dokhaegpyun, Sadanron, In-Eui-Ye-Ji of YuRiak and Bi-Bak-Tam-Ra'Ja. If we regard the In-Eui-Ye-Ji Sadan as the nature of human, many attritude can be possible and it may be different that apply a Sadan to the proper time and environment. Therefore, we have to be accepted change, as applying method than fixing idea.

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Assessment of climate change impact on aquatic ecology health indices in Han river basin using SWAT and random forest (SWAT 및 random forest를 이용한 기후변화에 따른 한강유역의 수생태계 건강성 지수 영향 평가)

  • Woo, So Young;Jung, Chung Gil;Kim, Jin Uk;Kim, Seong Joon
    • Journal of Korea Water Resources Association
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    • v.51 no.10
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    • pp.863-874
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    • 2018
  • The purpose of this study is to evaluate the future climate change impact on stream aquatic ecology health of Han River watershed ($34,148km^2$) using SWAT (Soil and Water Assessment Tool) and random forest. The 8 years (2008~2015) spring (April to June) Aquatic ecology Health Indices (AHI) such as Trophic Diatom Index (TDI), Benthic Macroinvertebrate Index (BMI) and Fish Assessment Index (FAI) scored (0~100) and graded (A~E) by NIER (National Institute of Environmental Research) were used. The 8 years NIER indices with the water quality (T-N, $NH_4$, $NO_3$, T-P, $PO_4$) showed that the deviation of AHI score is large when the concentration of water quality is low, and AHI score had negative correlation when the concentration is high. By using random forest, one of the Machine Learning techniques for classification analysis, the classification results for the 3 indices grade showed that all of precision, recall, and f1-score were above 0.81. The future SWAT hydrology and water quality results under HadGEM3-RA RCP 4.5 and 8.5 scenarios of Korea Meteorological Administration (KMA) showed that the future nitrogen-related water quality in watershed average increased up to 43.2% by the baseflow increase effect and the phosphorus-related water quality decreased up to 18.9% by the surface runoff decrease effect. The future FAI and BMI showed a little better Index grade while the future TDI showed a little worse index grade. We can infer that the future TDI is more sensitive to nitrogen-related water quality and the future FAI and BMI are responded to phosphorus-related water quality.

Fresh-water Algae Occurred in Paddy Rice Fields I. Regional Distribution (논발생(發生) 담수조류(淡水藻類)에 관(關)한 연구(硏究) I. 지대별(地帶別) 발생분포(發生分布))

  • Lee, H.K.;Park, J.E.;Ryu, G.H.;Lee, J.O.;Park, Y.S.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.158-165
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    • 1992
  • A survey on nation-wide distribution of fresh-water algae occurring in paddy rice fields was conducted in 1991. The algae which were collected from the whole nation were classified into a total of 54 genera including 14 genera in the blue-green algae. 29 genera in the green algae, 1 genus in the stoneworts. 3 genera in the euglenoids and 7 genera in the diatoms. The green algae and diatoms occurring in plain regions were diverse in terms of the number of genera distributed, whereas there was no regional difference in diversity of the blue-green algae and the euglenoids. Among the green algae, the suspended unicellular algae such as the genera, Chlamydomonas, Pandorina and Gonium, were widespread in plain regions, but the multicellular algae such as the genera, Spirogyra, Oedogonium, Ulothrix and Hydordictyon, were major in mountainous and attitudinal regions. The filamentous green algae such as the genera. Cladophora and Rhizoclonium, were dominant in reclaimed saline fields. The blue-green algae Oscillatoria spp. and the diatoms Navicula spp. were abundant in soil flakes.

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A Study Concerning the Background of Formation in Deleuze's System (들뢰즈 체계의 형성 배경에 대한 연구 - 칸트 선험철학 체계 그 심연으로부터의 역류 -)

  • Kim, Dae-hyeon
    • Journal of the Daesoon Academy of Sciences
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    • v.37
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    • pp.329-355
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    • 2021
  • The objective of this paper is to reveal that the formation of Deleuze's system is a result of a back flow of the 'ideal of pure reason' in Kant's system. I will try to seize upon the keyword in his main book, Difference and Repetition, and examine the aspect of mutual transformation between Deleuze's transcendental empiricism and Kant's transcendentalism. When analyzing Deleuze's system, most researchers tend to focus on anti-Hegelianism, but it is proper that Kant be adopted as the start when tracing the way of deployment directly. Fundamentally, Deleuze is different from Hegel in his approach to observing entire ground of thought. Even if Deleuze surely has the capability of becoming in the dialectical context, his systemic environment wherein dialectics is applied is different even at the onset. While Hegel follows the way of origin and copy or a system that begins from a preceding point of origin, Deleuze follows a way of copy and recopy or a system that begins without a point of origin. This characteristic of Deleuze's system originates directly from idealistic play. In fact, we can anticipate and identify in his book that he refers to Kant who accepted the tradition of empiricism. Therefore, the main contents of this paper is to present an overview of Kant's influence on Deleuze's system. While tracing ideas back to Kant's system, the cohabitation of empiricism and rationalism, which Kant felicitously revoiced, there emerges a definitude of world recognition. This occurs through cohabitation, and this is both deconstructed and integrated by Deleuze, and therein definitude is turned into a vision of prosperity. To the vision of prosperity that spans definitude to recognition, a philosopher has the right to select a philosophical system because selection methodology in philosophy is not a problem of legitimacy so much as the needs of the times. Deleuze's choice resulted in the opening of pandora's box in an abyss and secret contents have in turn risen sharply.

Comparison of Biological Responses and Heat Shock Protein 70 Expression in Chironomidae by Exposure UV and O3 (UV와 O3 노출에 따른 깔따구류의 생물학적 반응 및 열충격 단백질 70 발현)

  • Ji-Hoon Kim;Won-Seok Kim;Jae-Won Park;Bong-Soon Ko;Kiyun Park;Ihn-Sil Kwak
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.430-439
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    • 2023
  • UV and O3 are materials used in the water treatment process, and many studies have been reported to remove organic matters, contaminants, and microorganisms. In this study, we were investigated effects of Chirnomidae (Chironomus flaviplumus, Chironomus riparius), which are contamination indicator species to exposure UV and O3 for the survival rate, body color change and gene expression response. The survival rate of C. flaviplumus exposed to UV decreased to about 70% after 24 hours, and C. riparius about 50%. There was no change in the survival rate of C. flaviplumus exposed to O3, and C. riparius decreased to 95% after 10 minutes of exposure, but there was no change during the subsequent exposure time. In addition, UV and O3 exposure to the two species in body color faded in a time-dependent. In the HSP70 gene expression, C. riparius showed an increase in expression after UV exposure compared to the control group, and a significant difference was shown 12 hours after exposure (P<0.05). C. flaviplumus exposed to O3 showed a relatively low expression compared to the control group, and showed a significant difference at 10 minutes and 1 hour after exposure (P<0.05). These results reported the ecotoxicological effects on Chironomidae according to UV and O3 exposure. Therefore, the results of this study can be used as basic data to understand the effects of UV and O3, which are disinfectants used in water treatment plants, on Chirnomidae entering plants.