• 제목/요약/키워드: soil ecology

검색결과 1,221건 처리시간 0.032초

토양환경에서 항생제 내성 인자의 전이 및 생존 (Transfer and Survival of Genes Resistant to Antibiotics in Soil)

  • Lee, Geon-Hyoung;Lee, Jae-Sei
    • The Korean Journal of Ecology
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    • 제17권2호
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    • pp.223-235
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    • 1994
  • The transfer of plasmid-borne genes coding for resistance to antibiotics (Ampicillin, Carbenicillin, and tetracycline) among 16 strains isolated from Mankyong River was examined. The survival of donors, recipient, and transformants in sterile and nonsterile soil (the soil was amended with 12% vol/vol with the clay mineral, montmorillonite) was also studied. In sterile soil, the survival was prolonged in the order of donors, transformants, and recipient. The survival of donors, transformants, and recipient increased when the soil was amended with 12% montmorillonite, but not in nonsterile soil. In nonsterile soil, donors survived longer than transformants and recipient, but the survival of transformants and recipient showed no significant differences. The results of these studies suggest that genes can be transferred by transformation, and transferred genes can survive in soil for a considerable time.

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수분공급조절에 의한 족제비싸리의 생장과 내건성에 관한 연구 (Study on the Growth and the Drought Resistance of Amorpha fructicosa under the Control of Water Supply)

  • Hong, Kyung-Hae;Kim, Woen
    • The Korean Journal of Ecology
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    • 제5권2_3호
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    • pp.123-131
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    • 1982
  • The growth and the resistance of Amorpha fructicosa L. under water control was experimented in frames out of doors. The plant grew in a wagner's pot under water control. The soil moisture content was controlled at 5%, 10%, 15% and 20%. The growth of leaf, stem and root in the groups of 5% and 10% soil moisture content were different from values in the groups of 15% and 20%. The T/R ratio in the groups of 5% and 10% soil moisture content were different from the ratio in the groups of 15% and 20% soil moisture content. The T/R ratio of former was lower than the latter, but the C/F ratio of the former was higher than the latter. RGR and NAR of Amorpha fructicosa decreased in 5% and 10% soil moisture content but increased in 15% and 20% soil moisture content during growing period. The maximum values of RGR and NAR were respectively 0.089 and 0.080 at 20% soil moisture content. The highest value of LAR was 1.560 at 5% soil moisture content. RGR and NAR were comparatively affected by soil moisture content.

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石灰岩地域 소나무림에서 지렁이 Casts 와 上層土 性質의 比較 (Comparisons of Soil Properties between Earthworm Casts and Top Soil of Red Pine Forests in a Limestone Area)

  • Mun, Hyeong-Tae;Joon-Ho Kim
    • The Korean Journal of Ecology
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    • 제14권1호
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    • pp.113-117
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    • 1991
  • Comparisons of the physico-chemical properties of earthworm(Lumbricus terrestris) soil casts and top soil of red pine forests in a limestone area were carried out. The casts production durign August and September in 1990 amounted to 6∼7t/ha. The particle of top soil and casts ranged 40∼50% and 10∼20% for sand , 25∼30% and 30∼35% for silt, and 20∼25% and 55∼65% clay, respectively. Significant difference in pH value was not observed between casts and top soil. The casts had 1.4times of organic matter, 1.5times of N, 1.8times of available P, 2times of exchangeable K, 1.3times of exchangeable Ca, and 1.6times of exchangeable Mg than the top 10cm of soil did. Earthworms have altered the soil texture and increased nutrient availability through production of the soil casts in this limestone area.

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한국 논토양(土壤)에서 물관리(管理)와 볏짚 시용(施用)에 따른 메탄 배출량(排出量)의 추정(推定) (Estimation of Methane Emission by Water Management and Rice Straw Application in Paddy Soil in Korea)

  • 신용광;윤성호;박무언
    • 한국토양비료학회지
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    • 제28권3호
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    • pp.261-265
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    • 1995
  • 논토양에서 물관리 및 볏짚시용이 메탄배출에 미치는 영향을 알기 위하여 물관리로는 상시담수와 간단관개의 2처리로 하고 각각에 삼요소를 대조로 하여 볏짚의 시용효과를 조사하였다. 메탄배출량은 $0.066g\;CH_4m^{-2}d^{-1}{\sim}0.455g\;CH_4 m^{-2}d^{-1}$의 범위였다. 상시담수보다 간단관개의 NPK구에서는 70%, NPK+볏짚시용구에서는 47%의 메탄 배출저감효과가 인정되었다. 간단관개조건에서 볏짚을 전량 작토에 환원한다고 가정할 때 우리나라 메탄 총배출량은 399,590톤/년으로 추정된다. 이 양은 OECD의 참고값 대비 56%, Neue와는 51%, Matthew와는 62%로 낮고 Taylor와는 118%로 높다.

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Carbon balance and net ecosystem production in Quercus glauca forest, Jeju Island in South Korea

  • Jeong, Heon Mo;You, Young Han;Hong, Seungbum
    • Journal of Ecology and Environment
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    • 제46권3호
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    • pp.250-258
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    • 2022
  • Background: To assess the carbon sequestration capacity and net ecosystem productivity (NEP) of Quercus glauca forests, we analyzed the net primary productivity (NPP), carbon storage, and carbon emission of soil in a Q. glauca forest on Jeju Island (South Korea) from 2016 to 2018. Results: The average carbon stock in the above- and below-ground plant biomass was 223.7 Mg C ha-1, while the average amount of organic carbon fixed by photosynthesis was 9.8 Mg C ha-1 yr-1, and the average NPP was 9.6 Mg C ha-1 yr-1. Stems and branches contributed to the majority of the above- and below-ground standing biomass and NPP. The average heterotrophic carbon emission from the soil was 8.7 Mg C ha-1 yr-1, while the average NEP was 1.1 Mg C ha-1 yr-1. Although the carbon stock, carbon absorption, and soil respiration values were higher than those reported in other oak forests in the world, the NEP was similar or lower. Conclusions: These results indicator that Q. glauca forests perform the role of a large carbon sink through the CO2 absorption in the plants in terms of carbon balance. And it is judged to be helpful as data for assessment of carbon storage and flux in the forests and mitigation of elevated CO2 in the atmosphere.

AvSWAT를 이용한 농촌유역 비점원 오염물질 부하량 예측 (Estimation of Nonpoint Source Pollutant Loads for Rural Watershed by AvSWAT)

  • 김진호;이종식;김원일;정구복;한국헌;류종수;김석철;윤순강;이정택;권순국
    • 한국토양비료학회지
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    • 제40권1호
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    • pp.12-17
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    • 2007
  • 유역관리모형은 유역내 비점원 오염부하를 예측하고, 서로 다른 오염원과 토지이용형태에 따른 영향을 판단하는데 사용 되어진다. 많은 모형들이 비점원오염의 예측이 가능하지만, 각기 서로 다른 한계를 갖고 있다. 모델의 선택의 연구목적과 축적된 가용자료에 부합해야 한다. 최근 한국에서는 SWAT모형이 농촌유역의 비점원오염 유출을 예측하기 위해서, 많이 이용되고 있다. 대부분의 자료들이 GIS를 이용하여 자동적으로 생성되지만, 일부 자료들은 농민들과 연구자들을 통해 직접 수집해야 한다. AvSWAT모형에 의해 시뮬레이션된 유량과 관측유출은 매우 좋은 결과를 나타내었다. 그러나 유출은 경향은 주로 강우와 물부족기간에 의해 그 경향을 따라간다. AvSWAT 모형을 농촌유역에 적용하여 유출을 평가한 결과 모델치는 1023.3 mm이고, 관측치는 967.4 mm인 것으로 나타났다. 또한 수질의 경우 모델치와 관측치의 결정계수는 인이 질소보다 더 높은 값(0.79)을 보여주고 있었다.

Growth environment characteristics of the habitat of Epilobium hirsutum L., a class II endangered wildlife species

  • Kwang Jin Cho;Hyeong Cheol Lee;Sang Uk Han;Hae Seon Shin;Pyoung Beom Kim
    • Journal of Ecology and Environment
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    • 제47권4호
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    • pp.282-289
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    • 2023
  • Background: As wildlife habitats are being destroyed and growth environments are changing, the survival of animals and plants is under threat. Epilobium hirsutum L., a species that inhabits wetlands, has held legally protected status since 2012. However, no specific measures are currently in place to protect its habitat, leading to a decline in remaining populations as a result of land use change and human activities. Results: The growth environment (including location, climate, land use, soil, and vegetation) of the five habitat sites (Samcheok, Taebaek1, Taebaek2, Cheongsong, Ulleung) of E. hirsutum L. was investigated and analyzed. These habitats were predominantly situated in flat areas with gentle south-facing slopes, at an average altitude of 452.7 m (8-726 m) above sea level in Gangwon-do and Gyeongsangbuk-do. The average annual temperature ranged 11.5℃ (9.2℃-12.9℃), whereas the average annual precipitation ranged 1,304.5 mm (1,062.7-1,590.7 mm). The surrounding land use status was mainly characterized by mountainous areas, and human interference, such as agricultural land and roads, was commonly found in proximity to these natural habitats. Soil physicochemical analysis revealed that the soil was predominantly sandy loam with a slightly high sand content. The average pH measured 7.64, indicating an alkaline environment, and electrical conductivity (EC) averaged 0.33 dS/m. Organic matter (OM) content averaged 66.44 g/kg, available phosphoric acid (P2O5) content averaged 115.73 mg/kg, and cation exchange capacity (CEC) averaged 23.43 cmolc/kg. The exchangeable cations ranged 0.09-0.43 cmol+/kg for potassium (K), 10.23-16.21 cmol+/kg for calcium (Ca), 0.67-4.94 cmol+/kg for magnesium (Mg), and 0.05-0.74 cmol+/kg for sodium (Na). The vegetation type was categorized as E. hirsutum community with high numbers of E. hirsutum L., Persicaria thunbergii (Siebold & Zucc.) H. Gross, Phragmites japonica Steud., Humulus japonicus (Siebold & Zucc.), and Bidens frondosa L.. An ecological flora analysis, including the proportion of lianas, naturalized plants, and annual herbaceous plants, revealed that the native habitat of E. hirsutum L. was ecologically unstable. Conclusions: Analysis of the habitat of E. hirsutum L., a class II endangered wildlife species, provided essential data for local conservation and restoration efforts.

경관생태학의 개념, 원리 및 식생조사와의 관계 (Landscape Ecology Concept, Principles and Its Rlation to Monothematic (e.g. Vegetation) Survey)

  • Isaak, S. Zonneveld
    • The Korean Journal of Ecology
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    • 제21권4호
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    • pp.357-372
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    • 1998
  • Land (scape) ecology is a trans-disciplinary science studying the related systems at the earth surface, in their visual, structural and functional aspects. it serves as an umbrella under which abiotic and biotic sciences, in an integrated way, study the for each relevant land attributes and their interrelations. The spatial aspects of these relations have a special interest. Landscape ecology my have a pure scientific purpose, but usually is executed in an applied context, related to land evaluation for land use and conservation. Depending on the aim and application of the study, one of the land attributes may get special attention. Vegetation mapping may contribute to landscape ecological study but also benefit from it especially in case of reconnaissance surveys. This is because in less detailed surveys of any land attribute, like land form, soil, vegetation, one must necessarily apply landscape ecological principles in the survey methodology, including remote sensing.

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소백산국립공원 천동계곡의 식물군집구조분석 (Analysis on the Plant Community Structure of Chundong Valley in Sobaeksan National Park)

  • 이경재;조우;조재창
    • 한국환경생태학회지
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    • 제6권2호
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    • pp.134-146
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    • 1993
  • 소백산 천동계곡 삼림의 식물군집구조분석을 위하여 20개소에 조사구(1개조사구당 20$\times$25m)를 설정하고 식생조사를 실시하여 얻은 자료에 대하여 TWINSPAM에 의한 classification과 DCA ordination기법을 적용하여 분석하였고 환경인자와 식생과의 관계를 CCA기법으로 분석하였다. TWINSPAN 과 DCA에 의하여 4개 군집인 소나무군집, 굴참나무-신갈나무-소나무군집, 신갈나무군집, 물푸레나무군집으로 분리되었다. 교목상층군의 천이는 소나무$\longrightarrow$신갈나무, 굴참나무$\longrightarrow$물푸레나무로 추정되었다. CCA에 의한 ordination분석에서는 토양내의 pH. 유기물함량, $Ca^{++}$함량, $Mg^{++}$함량과 제 1, 2축과의 상관성이 인정되었고, 유기물, $Mg^{++}$함량과 물푸레나무군집 그리고 pH와 소나무군집과의 상관관계가 인정되었다. 그러나 환경인자와 수종과의 관계는 명료하지 않았다.

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