• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.18-21
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• 2007

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.84-84
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• 2019

• The Korean Journal of Ecology
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• v.17 no.2
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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.

• The Korean Journal of Ecology
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• v.5 no.2_3
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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.

• The Korean Journal of Ecology
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• v.14 no.1
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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.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.261-265
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• 1995

Methane flux from a rice paddy in Korea was measured to study the effects of water management and rice straw application on methane emission under different water managements ; flooding and intermittent irrigation, and with or without rice straw application. Methane emission ranged from 0.066 to $0.455g\;CH_4m^{-2}d^{-1}$. Intermittent irrigation has shown a mitigation effect of methane emission, 70% in NPK plot and 47% in NPK plus rice straw plot, relative to that of flooding. Methane emission from Korean paddy was estimated as 399,590tons per year assuming that paddy fields were managed under intermittent irrigation and rice straw application. This estimation was lower than that of OECD's by 56%, Neue's by 51%, and Matthew's by 62%, while higher than that of Taylor's by 118%.

• Journal of Ecology and Environment
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• v.46 no.3
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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.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.12-17
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• 2007

This study was conducted to evaluate the characteristics of nonpoint source pollutants discharge from a small rural watershed. A typical rural area in Gongju City, Korea, was selected as the research site. Water quality and quantity in streams and rainfall samples were analyzed periodically from May to October 2005. Pollutant loads were estimated from a nonpoint source pollution model (AvSWAT, Arcview Soil and Water Assessment Tool). During the rainy season, from June 26 to 30 September 2005 and the dry season, before 26 June and after 30 September 2005, biological oxygen demands and chemical oxygen demands accounted for 91.3% and 93.7% of annual load, respectively, while total-N and total-P were 97.1% and 91.1% of annual load, respectively. The observed stream flow was $66.5m^3sec^{-1}$, while simulation stream flow was $66.2m^3sec^{-1}$. That can be assumed that simulation can be used to estimate the stream flow without practical measurement. However, the runoff trend following the occurrence of a storm event was not recorded properly.

• Journal of Ecology and Environment
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• v.47 no.4
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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.

• The Korean Journal of Ecology
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• v.21 no.4
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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.