• Korean journal of applied entomology
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• v.51 no.3
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• pp.285-293
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• 2012

Occurrence Hyphantria cunea was confirmed in 35 cities and counties nationwide in 2011, each of which reported some form of crop and/or ecological damage caused by the moth. Only a larva of the black-headed form were reported to have occurred in the nation. H. cunea was found in street trees 66.7%, followed by landscape trees 19.4% and forests 13.9%. This suggests that artificial environment 86.1% suffered from H. cunea more severely than natural forests. The study identified 44 families and 102 species of host plants, and found an additional 29 species, to those which had been identified in previous studies. At present, the identified host plants of H. cunea are composed of 62 families and 219 species in total since their first appearance was reported approximately 50 years ago. Host plants include 5 species of food crops (2.3%), 6 species of vegetables (2.7%), 4 species of medicinal crops (1.8%), 1 species of industrial crops (0.5%), 13 species of fruit trees (5.9%), 6 species of other trees crops (2.7%) as well as a further 5 species of farmed crops (2.3%). Seven species of host plants (18.4%) originate from North America where Hyphantria cunea has been introduced from, while 11 species (29.0%) are from China and Japan, Europe and India were the native sources of (10.5%) of the origin with 4 species, respectively. Seventeen species of trees, including Platanus occidentalis L., Ulmus davidiana (var.) japonica (Rehder) (Nakai) and Cornus officinalis (Siebold & Zucc) were heavily noted to be heavily infected with larval populations.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.44.1-44.1
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• 2015

We present joint constraints on the number of effective neutrino species $N_{eff}$ and the sum of neutrino masses ${\Sigma}m_{\nu}$, based on a technique which exploits the full information contained in the one-dimensional Lyman-${\alpha}$ forest flux power spectrum, complemented by additional cosmological probes. In particular, we obtain $N_{eff}=2.91{\pm}0.22$ (95% CL) and ${\Sigma}m_{\nu}$ < 0.15 eV (95% CL) when we combine BOSS Lyman-${\alpha}$ forest data with CMB (Planck+ACT+SPT+WMAP polarization) measurements, and $N_{eff}=2.88{\pm}0.20$ (95% CL) and ${Sigma}m_{\nu}$ < 0.14 eV (95% CL) when we further add baryon acoustic oscillations. Our results tend to favor the normal hierarchy scenario for the masses of the active neutrino species, provide strong evidence for the Cosmic Neutrino Background from $N_{eff}{\approx}3$($N_{eff}=0$ is rejected at more than $14{\sigma}$), and rule out the possibility of a sterile neutrino thermalized with active neutrinos (i.e., $N_{eff}=4$) - or more generally any decoupled relativistic relic with $${\Delta}N_{eff}{\sim_=}1$$ - at a significance of over $5{\sigma}$, the strongest bound to date, implying that there is no need for exotic neutrino physics in the concordance ${\Lambda}CDM$ model.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.212-218
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• 2019

Background: Allelopathy has been suggested as one potential mechanism facilitating the successful colonisation and expansion of invasive plants. The impacts of the ongoing elevation in atmospheric carbon dioxide (CO₂) on the production of allelochemicals by invasive species are of great importance because they play a potential role in promoting biological invasion at the global scale. Common ragweed (Ambrosia artemisiifolia var. elatior), one of the most notorious invasive exotic plant species, was used to assess changes in foliar mono- and sesquiterpene production in response to CO₂ elevation (389.12 ± 2.55 vs. 802.08 ± 2.69 ppm). Results: The plant growth of common ragweed significantly increased in elevated CO₂. The major monoterpenes in the essential oil extracted from common ragweed leaves were β-myrcene, DL-limonene and 1,3,6-octatriene, and the major sesquiterpenes were β-caryophyllene and germacrene-D. The concentrations of 1,3,6-octatriene (258%) and β-caryophyllene (421%) significantly increased with CO₂ elevation. Conclusions: These findings improve our understanding of how allelochemicals in common ragweed respond to CO₂ elevation.

• Journal of Ecology and Environment
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• v.37 no.2
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• pp.81-90
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• 2014

This study examined the main factors affecting the distribution of Phytolacca americana, an exotic plant species in Korea, in coastal sand dunes. The areas examined from June 2004 to February 2006 were in Sindusagu where was located on Sindu-ri, Wonbuk-myen, Taean-gun, Chungcheongnam-do. The vegetation, sediment properties, sizes and ages of Robinia pseudoacacia, P. americana and Pinus thnunbergii and spatial distribution of P. americana were assessed. Firstly, correlation coefficients (CC) between P. americana's root biomass and sediment properties were not significant. Secondly, of the four community types, P. americana was not in the mixed herbaceous community and its density was the highest in the P. thunbergii-R. pseudoacacia and R. pseudoacacia community The Poisson distribution analysis revealed the distribution of P. americana to be severely clumped. The root biomass of P. americana and the basal area of R. pseudoacacia were significantly correlated, but the CCs between P. thunbergii and other two species were not significant. The ages of P. americana and R. pseudoacacia in a quadrat were significantly correlated. Thirdly, P. americana's ages in a quadrat were mostly similar to each other. Therefore, the spatial distribution of P. americana was largely influenced by R. pseudoacacia but not by the sediment properties, and plants in a narrow area were concurrently germinated.

• Animal cells and systems
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• v.10 no.1
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• pp.27-40
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• 2006

Tree of heaven (Ailanthus altissima Swingle) as an invasive alien plant, appeared usually in the disturbed locations such as road-side, incised slope, and trampling path-side. They appeared abundantly in the trampling pathside but they did not appear or were rare in the interior of forest. Density and importance value of tree of heaven were proportionate to the relative light intensity measured according to distance from the trampling path toward forest interior and closely related to the breadth of trampling path as well. They were associated with annual, other exotic species or ruderal plants well. Distributional pattern of mature trees of them in the study area and its surrounding environments implied that they were introduced intentionally. Size class distribution of them showed that they are in expansion and artificial interferences such as, installing physical training space and developing hiking course functioned as trigger factors in their invasion and expansion. The results support the facts known generally in relation to invasion and expansion of the invasive alien plants. In this viewpoint, we suggest a management plan that applies ecological restoration principles to address ecosystems infected with tree of heaven by restoring the integral feature of the degraded nature and conserving the remained nature more thoroughly.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.12-20
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• 2004

This study was carried out from January 1998 to December 1999 to report the revegetation of cutting-rock slopes and a design standard in the highway cut-slopes. The field data was collected from the 67 sites cutting-rock slopes of highways, local roads, and field test. As the result of analyze, cutting-rock slopes revegetation measures were 16 types. There were Vine planting(3 types), Hydroseeding measures with seed-fertilizer-soil materials(5 types), Vegetaion-base spraying measures(5 types), and Stability measures(3 types). The factors affecting the plant coverage rates of cutting-rock slopes were the slope gradient, the slope width and direction. The plant coverage rate decreases in the condition of steep slope and long slope width and length(height). In addition, the plant coverage rates of the westward and southward were lower than that of the northward and eastward. Most dominant species were Zoysia japonica, Lespedeza cyrtobotrya, Lespedeza cuneata, Rubus crataegifolius, Miscanthus sinensis, Arrundinella hirta, Themeda triandra, and Oenothera odorata. Exotic species were Eragrostis curvula(Weeping lovegrass), Dactylis glomerata Orchardgrass), Lolium perenne(Perennial ryegrass), and Festuca arundinacea(Tall fescue). It is recommended to adjust the proposed factor as environment, topsoil, classification of rock, field condition and characteristic related with revegetation measures on slopes for the presentation of revegetation standard.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.516-523
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• 2006

Marginal soils such as BRlS (Beach Ridges Interspersed with Swales) soils and ex-tin mining land make up approximately 0.5 million ha or about 2% of Malaysia's land area. In the coastal areas of the east coast of Peninsular Malaysia impoverished sandy BRIS dominates the landscape with most lying idle as there is no national management plan for their utilization. A field study was carried out to see whether mycorrhizal application had any effect on the growth of three exotic Acacia spp., i.e. Acacia auriculiformis, A. mangium and Acacia hybrid (A. auriculiformis ${\times}$ A. mangium) on BRIS soils. Two types of mycorrhizal inoculum, namely, a commercially available arbuscular mycorrhizal inoculum marketed as $MycoGold^{TM}$ and an indigenous ectomycorrhizal Tomentella sp. inoculum were tested. In the initial six months, height growth of all three tree species inoculated with the arbuscular mycorrhizal inoculum was significantly improved compared to the ectomycorrhizal inoculated and uninoculated control plants. The mycorrhizal effect was not evident thereafter and repeated application of the arbuscular mycorrhizal inoculum may be necessary for continued growth enhancement. Of the three species, A. mangium had the highest relative height growth rate over the 24 months on BRlS soils.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.99-104
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• 2013

To detect five plant viruses (Beet black scorch virus, Beet necrotic yellow vein virus, Eggplant mottled dwarf virus, Pelargonium zonate spot virus, and Rice yellow mottle virus) for quarantine purposes, we designed 15 RT-PCR primer sets. Primer design was based on the nucleotide sequence of the coat protein gene, which is highly conserved within species. All but one primer set successfully amplified the targets, and gradient PCRs indicated that the optimal temperature for the 14 useful primer sets was $51.9^{\circ}C$. Some primer sets worked well regardless of annealing temperature while others required a very specific annealing temperature. A primer specificity test using plant total RNAs and cDNAs of other plant virus-infected samples demonstrated that the designed primer sets were highly specific and generated reproducible results. The newly developed RT-PCR primer sets would be useful for quarantine inspections aimed at preventing the entry of exotic plant viruses into Korea.

• Korean Journal of Environment and Ecology
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• v.19 no.2
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• pp.119-129
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• 2005

This study was carried out to investigate the actual vegetation and the DGN(Degree of Green Naturality) and the planting status of landscaping plants in the Woraksan National Park in 2004. The actual vegetation of the surveyed site were classified into 12 plant community and cropland; Natural forest were classified into 8 plant communities; Quercus mongolica communities, Pinus densiflora communities, Deciduous broadleaf forest, Mixed forest, etc. And artificial forest were classified into 3 forest types: Larix kaempferi forest, Pinus koraie-nsis forest, etc. The DGN 8 appeared in the widest area as $73.08\%$, and the DGN 9 was $11.32\%$. The planting status of landscaping plants at the surveyed site were recorded as total 129 species, 44 Family. The exotic plant of surveyed site was $65.65\%$.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1274-1279
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• 2005

The complex vegetation and plant species distributions within riparian corridors influence plant species diversity patterns at both local and regional scales and further reflect both natural and anthropogenic disturbances. Because of these characteristics, riparian zones are often the ecosystem level component that are most sensitive to changes of the surrounding environment; they provide early indications of environmental change and can be viewed as the important source in the watershed. The objectives of this study were two concepts: first, document the composition and dominance of plant communities of riparian areas in the stream, second, compare species composition and temporal diversity between stations in riparian areas of the Ian Stream. The flora was composed to total 158 kinds of the vascular plants as 49 family, 54 genera, 145 species, 12 varieties, 1 forma When the naturalized plant were applied to the recent classification system 280 kinds, the naturalization rate was $10.8\% higher than that of mean value($10.3\%$) of the Korean mountain district. Furthermore, urbanization index (UI) was $6.1\%$. The dominant vegetation communities were distributed in the habitats of three compartments from upstream to downstream. The vegetations were included Phragmites japonica, Salix gracilistyla, S. hulteni and Robinia pseudo-acacia in the riparian area, and Persicaria sieboldii, Stellaria alsine var. undulata, Draba nemorosa var. hebecarpa, Capsella bursa-pastoris, Lepidium apetalum, Bidens frondosa, Trigonotis peduncularis and Hemistepta lyrata in the sandbank or the riparian area, and Equisetum arvense, Humulus japonicus, Persicaria perfoliata, Trifolium repens, Artemisia princeps var. orientalis, Lactuca indica var. laciniata, Avena fatua, Agropyron yesoense, Oenothera odorata, Viola mandshurica, Rumex crispus in banksides, respectively.