• 제목/요약/키워드: Tolerant species

검색결과 367건 처리시간 0.022초

남한강수계의 하천차수별 어류군집 분포 특성 (Distribution Characteristics of Fish Community to Stream Order in Namhan River Watershed)

  • 이승현;이황구;박상정;이수형;최준길
    • 생태와환경
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    • 제47권spc호
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    • pp.100-115
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    • 2014
  • 본 연구는 2007년 11월부터 2010년 9월까지 2차 하천부터 6차하천까지 하천 차수에 따라 총 51개의 지점을 7회에 걸쳐 조사하였다. 채집된 어류는 총 12과 55종이었으며, 전체 지점에서 참갈겨니 (Zacco koreanus)가 우점하고, 피라미 (Zacco platypus)가 아우점 하였다. 또한 천연기념물 1종 (1.8%), 환경부지정 멸종위기야생동물 2급 6종(10.9%), 한국고유종 22종(40.0%)이 확인되었다. 하천차수가 2차하천에서 6차하천으로 증가할수록 종수, 다양도지수, 균등도지수, 종풍부도지수, 내성종, 잡식종이 증가하며, 개체수, 우점도지수, 민감종, 충식종, IBI종합 지수는 감소하는 경향이 나타났다. 주성분 분석결과 각 지점들의 분포양상은 종수, 개체수, 군집지수, 내성종, 민감종, 잡식종, 충식종에 따라 상류와 하류로 구분이 되었다. 다변량 상관관계 분석결과 하천차수와 다변수(종수, 다양도지수, 잡식종, 하폭, 수심, 수온)는 유의미한 양의 상관관계가 나타났다.

Dry Matter Accumulation and Leaf Mineral Contents as Affected by Excessive Soil Water in Soybean

  • Seong, Rak-Chun;Kim, Jeong-Gyu;Nelson, C. Jeny
    • 한국작물학회지
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    • 제44권2호
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    • pp.129-133
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    • 1999
  • Excessive soil water at vegetative growth stages during the rainy season induces yield losses in soybeans. Our objectives were to obtain basic information about the cultivar differences and to understand the stress-tolerance process for due to excessive soil water. Previous experiments revealed soybean genotypic differences in tolerance to excessive soil water. A field experiment was conducted at the Research Farm of Korea University near Seoul on 21 May 1998. Soybean[Glycine max (L.) Merrill] cultivars, 'Hannamkong' (sensitive) and 'Taekwan-gkong'(tolerant) were planted in vinyl-lined plots(1.2 x 4.2 x 0.3 m deep) and control plots. Drip irrigation began at VI growth stage to submerge the soil surface. Three weeks of excessive soil water treatment reduced all growth parameters measured to soybean plants. Excessive soil water stress resulted in decreases of N, P, K, Ca, Mg and Cu, and increases of Fe and Mn contents in soybean leaves. The stress index of tolerant cultivars under excessive soil water showed no large difference in soybean growth characteristics measured at three growth stages. However, K, Ca, Mg, Fe and Mn contents in soybean leaves appeared to differ between sensitive and tolerant cultivars. From the above results, stress and tolerance indices are proposed for a method to test cultivar differences in plant responses within a species under adverse growth environments.

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Four Unrecorded Species of Tubificid Oligochaetes (Annelida: Clitellata) in Korea

  • Lee, Jeounghee;Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
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    • 제30권4호
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    • pp.240-247
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    • 2014
  • Tubificid oligochaetes are common and frequently dominant in freshwater benthic habitats. They are so tolerant to water pollution that they are often used as biological indicators. Faunistic studies of Korean freshwater oligochaetes have been actively conducted recently. The most well studied oligochaete family in Korea is the tubificids following the naidids. Nine species of tubificids have been reported so far. Nevertheless, many species of tubificids still remain to be discovered in Korea. In this study, we added four species of tubificid oligochaetes to the Korean fauna, including Linmodrilus profundicola (Verrill, 1871), Potamothrix heuscheri (Bretscher, 1900), Tubifex blanchardi $Vejdovsk\acute{y}$, 1891, and Ilyodrilus templetoni (Southern, 1909) based on specimens collected from three locations in Korea: Cheonan-si, Geoje-si, and Seocheon-gun. In particular, P. heuscheri was first reported in Asia.

답압으로 훼손된 임간나지의 임상식생 복원에 관한 연구(II) -자생 수종선발을 위한 생장력 비교- (Studies on Restoraation of Forest-Floor Vegetation Devastated by Recreational Trampling(II) -A Comparison of Growth for Selection of Native Tree Species-)

  • 오구균;우보명
    • 한국조경학회지
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    • 제21권1호
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    • pp.51-61
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    • 1993
  • Seeding treatment was used for 2 years at an artificial bare ground for selecting tree species suitable for forest-floor revegetation. 2 ${\times}$2${\times}$2 factorial experiment was used with a randomized complete block design for 19 native tree species and results were summarized as follows; 1. Native species suitable for restoration of bareland under 75% shading in central part of Korea were Styrax japonica, Styrax obassia, Smilax china, Callicarpa japonica, Stephanandra incisa, Viburnum dilatatum for. pilosulm, Magnolia sieboldii, Cornus kousa, Celastrus orbiculata, etc.. Especially, Magnolia sieboldii, Stephanandra incisa and Stryrax obassia were tolerant for forest-floor with hardened woil surface and Callicarpa japonica, Viburnum dilatatum for. pilosulum, Euonymus sieboldianus and Philadelphus schrenkii were suitable for softened soil surface with straw-mat mulching. 2. It is necessary to break seed dormancy to accelerate germination in case of Styrax obassia, Styrax japonica, Viburnum dilatatum for. pilosulum, Smilax china and Stephanandra incisa.

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감수성(感受性)이 다른 작물(作物)과 잡초(雜草)에 있어서 Chlorsulfuron 의 대사작용(代謝作用) (Metabolismus von 14C-Chlorsulfuron in Verschieden Empfindlichen Kulturpflanzen und Unkrautern)

  • 강병화
    • 한국잡초학회지
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    • 제4권2호
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    • pp.115-124
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    • 1984
  • Chlorsulfuron (chemical name : 2-Chloro-N-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-aminocarbonyl-benzenesulfonamide) is a herbicidally active ingredient which shows effect against susceptible weeds already at such low rates like 5-20g active ingredient per hectare. In the here reported trials metabolism in several sensitive cultivated plants and weeds have been analysed using ^{14}C-labelled active ingredient. The uptake of chlorsulfuron by leaves or the root system is good in all plants species, and translocation takes place either symplasmatically or apoplasmatically. Metabolism takes place in all investigated plant species by development of hydrophile suhstances in roots and shoots. Decomposition of chlorsulfuron in roots and shoots of tolerant species (Triticum aestivum and Hordeum vulgare) to polare substances takes place quantitatively faster and quicker than in susceptible species (Beta vulgaris and Matricaria chamomilla).

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마산저수지의 어류 종조성 및 생태 지표 특성 분석 (Analysis of Fish Compositions and Ecological Indicator Characteristic in Masan Reservoir.)

  • 한정호;이의행;안광국
    • 생태와환경
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    • 제42권2호
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    • pp.212-220
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    • 2009
  • 본 연구는 2008년 11월에 마산저수지를 대상으로 어류 종조성 및 섭식길드 및 오염내성길드에 따른 생태지표 특성을 분석하고, 이와 연관된 화학적 수질 특성 변화를 분석하였다. 채집된 어류는 총 12종(6과)으로 나타났고, 주요 우점종은 피라미, 치리, 참붕어 등으로 나타났다. 한국 고유종은 3종만이 출현하였으며, 외래도입종은 떡붕어 1종이 출현하였다. 생태지표 특성 분석에 따르면, 내성종 및 잡식종의 상대풍부도는 각각 98%로 단연 우점하는 것으로 나타나, 이화학적 질적저하 및 물리적 서식지 교란요인에 의한 영향을 반영하고 있었다. 호안에 따른 종분포 특성 분석 결과, 정수식물이 발달한 호안에서 대부분의 어류가 95% 이상이 채집된 것으로 나타났다. 또한 하상 기질 특성에 따른 분석 결과, 뻘(Silt)로 된 구간에서 가장 많은 종 (11종, 91.7%)이 채집되어, 하상기질에 따라 유의한 차이를 보이고 있었다. 화학적 수질자료 분석에 따르면, 호수 영양상태 지표인 총인(TP) 및 Chl-a의 농도는 모두 과영양상태인 것으로 나타났으며, 호수의 유기물오염의 지표로 사용되는 COD도 평균 10.9 mg $L^{-1}$로 나타났다. 마산저수지의 이러한 수질저하는 어류의 섭식구조(잡식종의 증가) 및 내성종의 증가 등을 통해 반영되었다. 향후 마산저수지의 어류상 및 어류 종조성이 향상을 위해서 수질 개선 및 서식지 복원이 펼요할 것으로 사료된다.

대량배양에 적합한 Tetraselmis종의 선택 (Selection of Optimum Species of Tetraselmis for Mass Culture)

  • 김철원;허성범
    • 한국양식학회지
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    • 제11권2호
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    • pp.231-240
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    • 1998
  • 온도와 염분에 대하여 내성이 강하고 대량배양이 쉬워서 조개류의 인공종묘생산시 먹이로서 많이 사용하고 있는 5종의 Tetraselmis (T. tetrathele, T. suecica, T. subcordiformis, T. sp. (Haeundae), T. sp (China)) 중 우리나라 기후 환경에 대향배양이 가장 적합한 종을 선택하기 위핵서 최적 배양환경 (온도, 염분)을 조사하고 이때의 세포크기와 영양성분을 조사하였다. 5종의 Tetraselmis의 세포크기 및 체적은 T. sp. (Haeundea)가 장경 $17.6{\pm}1.87$${\mu}$m, 체적 727${\mu}$$m^3$로 가장 대형종이었으며 중국산 T. sp.가 장경14.6+- 1.46${\mu}$m, 체적 625${\mu}$$m^3$으로 가장 소형종이였다. Tetraselmis는 광염성, 광온성이나 최적성장을 위한 수온과 염분 구간은 각각 24~$30^{\circ}C.$와 27~30%.였다. 5종의 Tetraselmis에서 고수온에 대한 내성은 중국산 Tetraselmis, 저수온데 대한 내성은 T. tetrathele가 높은 것으로 나타났다. 5종의 Tetraselmis중 배양밀도가 가장 높았던 종은 T. suecica였으며, 이 종은 배양 7일째 $24^{\circ}C.$, 30%.에서 세포수가 $141{\times}10^4$cells/ml (s.g.r., 0.3906)로 성장이 가장 좋았다. 5종의 Tetraselmis의 화학성분중 조단백질 함량은 T. suecica가 44.50%로 가장 높게 나타났고 조지방은 해운대산 T. sp.가 7.13%로 높게 나타났다. 필수아미노산은 해운대산 .T.sp.에서 50.40%로 가장 높게 나타났고, 불포화지방산은 중국산 T.sp.에서 11.7%로 가장 높게 나타났다. 5종의 Tetraselmis의 성장과 영양성분 결과로 보아 우리나라에서 대량배양이 가장 적합한 종은 T. seucica임을 알수 있었다.

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Diversity of Leuconostocs on Garlic Surface, an Extreme Environment

  • KIM, MYUNG HEE;SUN TAEK SHIM;YOUN SOON KIM;KYU HANG KYUNG
    • Journal of Microbiology and Biotechnology
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    • 제12권3호
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    • pp.497-502
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    • 2002
  • Thirty-nine strains of Leuconostocs found to be tolerant to $10\%$ or more garlic were selected for further identification, by comparing their whole-cell protein pattern, 16S rRNA gene (first 530 bases) sequence, cellular fatty acid composition, and carbon source metabolism. Two isolates were Identified as Leuconostoc mesenteroides and 32 others as Leuconostoc citreum. Five other strains belonging to a cluster could not be allocated to the existing species. 16S rRNA gene sequence and cellular fatty acid composition of the unidentified bacteria exhibited close similarity with Leuconostoc argentinum. The unidentified isolates were not allocated to L. argentinum, because they formed polysaccharide from sucrose, while L. argentinum strains do not. Leuconostocs tolerant to high concentration of garlic were found predominantly on garlic surface, an extreme environment which is unfit for most of other microorganisms.

Ecological Comparisons of Stream Conditions Between the Unimpacted and Impacted Sites: Case Study

  • Lee, Jae-Hoon;Lee, Sang-Jae;An, Kwang-Guk
    • 생태와환경
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    • 제41권4호
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    • pp.441-448
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    • 2008
  • The purpose of this study was to analyze chemical water quality, fish trophic guilds, tolerance indicators, and fish community conditions in the Gap Stream and to compare the stream conditions between the unimpacted site and impacted site. This study was conducted in the physically stable season (May 2008) to minimize physical impacts such as flow and hydrological disturbance, and applied the study in the Gap Stream with two sites of unimpacted upstream site (Unim-S), mainly surrounded by forested area and impacted site (Im-S), influenced by the wastewater disposal plants and industrial complex in the urban region. Chemical data analysis showed that the degree of organic matter pollution, based on BOD, and COD, was $2{\sim}3$ fold greater in the Im-S than the Unim-S, and that TP, as eutrophication indicators, was 4.7 fold greater in the Im-S. Also, $NH_3-N$ was in 8.2 fold greater in the Im-S ($6.25\;mg\;L^{-1}$) than the Unim-S ($0.76\;mg\;L^{-1}$), indicating a massive influence of wastewater from the disposal plant. Similar results were found in other chemical parameters. Thus, chemical impacts in the Im-S were evident, compared to the unimpacted site. Evaluations of tolerant indicator species indicated that sensitive species were dominant in the Unim-S (23.9%) and tolerant species were dominant (97.8%) in the Im-S. Condition factor (CF) was averaged 0.95 ($0.68{\sim}1.18$) in the Unim-S and 1.08 ($0.93{\sim}1.22$) in the Im-S. Fish community in the Unim-S and Im-S was categorized as Zacco-community and Hemibarbus-community, respectively, and the community diversity index (H') was significantly (p<0.05) higher in the Unim-S (0.810) than the Im-S (0.466). Overall, our results suggest that the comparison approach of various chemical and ecological indicators provide important information in identifying multiple stressors in the stream ecosystems.

Application of Indigenous Benthic Amphipods as Sediment Toxicity Testing Organisms

  • Lee, Jung-Suk;Lee, Kyu-Tae;Kim, Dong-Hoon;Kim, Chao-Kook;Lee, Jong-Hyeon;Park, Kun-Ho
    • Ocean Science Journal
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    • 제40권1호
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    • pp.17-24
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    • 2005
  • A series of experiments were conducted to develop standard test organisms and test protocols for measuring sediment toxicity using candidate amphipods such as Mandibulophoxus mai, Monocorophium acherusicum, Haustorioides indivisus, and Haustorioides koreanus, which are indigenous to Korea. The relevant association of test species with sediment substrates was one of the important factors in sediment bioassay. The indigenous amphipods M mai and M. acherusicum were well associated with test sediments when they were exposed to various sediment substrates from sand to mud. The tolerant limits to various physico-chemical factors affecting bioassay results such as temperature, salinity and ammonia, as well as sensitivities to reference toxicant and contaminated sediments, were investigated using M. mai and M. acherusicum in the present study. These amphipods were tolerant to relatively wide ranges of salinity $(10{\sim}30\;psu)$ and ammonia (<50 ppm), and displayed relevant sensitivity to temperature as well. They are more sensitive to Cd, the reference toxicant, when compared to the standard test species used in other countries. Field-sediment toxicity tests revealed that M. mai would be more sensitive to sediment-associated pollutants than M. acherusicum, while the sensitivity of M. acherusicum was comparable to that of Leptocheirus plumulosus, which has been used as a standard test species in the United States of America. Overall results of this first attempt to develop an amphipod sediment toxicity test protocol in Korea indicated that M. mai and M. acherusicum would be applicable in the toxicity assessment of contaminated sediments, following the further evaluation encompassing various ecological and toxicological studies in addition to test method standardization.