• Research in Plant Disease
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• v.14 no.1
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• pp.1-9
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• 2008

The severe damage induced by the important viruses of Rice stripe virus (RSV), Cucumber green mottle mosaic virus (CGMMV), Melon necrotic spot virus (MNSV), Tomato spotted wilt virus (TSWV) and Tomato bushy stunt virus (TBSV) was described on major crops in Korea. In 2007, the plot incidence rate of RSV was 100% on the precocious rice cultivars at the Western coastal provinces of Gyeonggido, Chungcheongnamdo, Jellabugdo and Jellanamdo, and Jejudo. RSV occurred in 2,441 ha with incidence rate of 70% over at 5 areas of Seocheon, Seosan, Boryung, Hongsung and Buyou in Chungcheongnamdo. At 4 areas of Buan, Gimje, Gunsan and Gochang in Jellabukdo, RSV occurred in 2.016 ha. CGMMV occurred on watermelon in 4.6 ha at Cheongyang area, and its outbreak was also 890 ha on oriental melon for 120 farmers with the incidence area of 23% against total cultivation areas of Seongju. MNSV was recorded firstly on watermelon in 2006 at Andong and it spread to 3 areas of Hapcheon, Gochang and Yanggu. TSWV occurred firstly at Danggin in Chungcheongnamdo in 2005. TSWV in 2006 spread to 6 areas; Taian, Hongsung and Seosan in Chungcheongnando, Namwon in Jellabukdo, and Sunchon and Kwangju in Jellanamdo. In 2007, TSWV covered 17 areas of western and southern parts; the 5 area including Taian in Chungcheongnamdo, Kwangju in Jellanamdo, Bucheon in Gyunggido, and so forth. TBSV was described firstly on table tomato at Sacheon in Kyungsangnamdo in 2004. TBSV occurred on cherry tomato at Chungju in 2006 and on table tomato at Busan area.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.252-259
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• 2013

BACKGROUND: Salt accumulation in coastal reclaimed soil can decrease plant growth and productivity, which could lead to considerable variation of methane($CH_4$) emission in a rice paddy. The objective of this study was to evaluate the effect of salt concentration on $CH_4$ emission in a coastal reclaimed soil. METHODS AND RESULTS: The effect of salt concentration on $CH_4$ emission and rice growth characteristics was studied by pot test, which packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Electrical conductivity(EC) of each treatment was controlled by 0.98, 2.25, 5.05 and 9.48 dS/m and $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. The $CH_4$ emission rate was significantly decreased with increase of salt accumulation, but total $CH_4$ flux in EC 5.50 dS/m treatment was lower than those of EC 9.48 dS/m treatment. It seems because of higher content of water soluble $SO{_4}^{2-}$ in EC 5.50 dS/m treatment than those of EC 9.48 dS/m treatment. Rice growth and grain yield were significantly decreased with increase of salt accumulation. Soil properties, especially EC and pH were negatively correlated with $CH_4$ flux, while rice growth characteristics like plant height and tiller number show significantly positive correlation with $CH_4$ flux. CONCLUSION(S): Conclusively, salt accumulation significantly decreased $CH_4$ flux in a rice paddy, which could be useful information for evaluating $CH_4$ flux in reclaimed area in Korea.

• The Korean Journal of Ecology
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• v.22 no.3
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• pp.109-117
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• 1999

Thirty two species of coastal plants (mainly halophytes) were investigated for their free amino acids and the total and water-soluble nitrogen contents in leaves. All plants except some species (e.g. Scutellaria and Linaria) contained proline, but only Ageratum. Tetragonia and Raphanus in rather high amounts, that it can be thought to serve as a cytoplasmic osmolyte. In some plant species (Euphorbia. Glehnia. Peucedanum. Raphanus and monocotyledonous Carex and Zoysia), however, hydroxyproline. (OH-Pro) rather than proline were accumulated to a considerable extent. The concentrations of total free amino acids were low in Aster tripolium, Linaria. Lysimachia. Plantago. Rumex, Vitex and especially in the members of the Chenopodiaceae and Crassulaceae. Marked differences also occurred in the nitrogen levels. Aizoaceae, Chenopodiaceae, Convolvulaceae, Cruciferae, Euphorbiaceae and Leguminosae usually showed high values of total and soluble amino nitrogen, while the opposite was true for most of the Cyperaceae, Gramineae, Lamiaceae, Plantaginaceae, Scophuriaceae, and Verbenaceae. The free amino acids in the investigated plant species contributed very little to the nitrogen content, but in plants of Euphorbia, Messerschmidia and Orostachys. their amino acid-N made up for 25∼30% of the total nitrogen. In conclusion, only a few cases did proline known as compatible solute constitute a significant proportion of the free amino acid pool in coastal plants.

• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.437-445
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• 2012

The study performed the implementation monitoring of the revegetation methods applied to the test-bed of Simgok Stream in Incheon to identify the effect of water level and inundation period on the vegetation coverage of the stream bank revegetation methods. The categories of monitoring included the plant species and plant coverage for each method, physicochemical property of soil, water level and water quality. The result of monitoring revealed that plant growth conditions of all revegetation methods of each stream bank were good in the first survey as of May 2010. However, in the second survey of June 2011 when inundation period was less than a week, plant growth conditions and coverage of revegetation methods were partially bad. In the third survey as of August 2011 when inundation period was longest as 8 weeks during survey period, most vegetations did not survive except for Phragmites communis. But plant species number and plant coverage were increased gradually in the forth survey as of October 2011 when inundation period was less than 2 weeks so water level decreased more than that of third survey. Accordingly, the correlation analysis among number of plant species and plant coverage on stream bank, which applied revegetation method, water level and inundation period was performed for quantitative analysis. The result revealed that number of plant species and plant coverage has a negative correlation with water level and inundation period, but inundation period had higher correlation with plant occurrence than water level.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.28-36
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• 2012

Forests are one of the basic assets nearest our daily lives that provide the foundation of life necessities, culture and even survival. These assets pervade local residents' lives as culture and the necessities of life, and they will be handed down to posterity. Therefore, this study was conducted to carry out a field survey on old trees, plant communities and forests in the southern coastal areas in Korea, where not many surveys were not conducted on the forest cultural assets, further examining a possibility that some of the trees should be designated as law-protected. As for the survey of plants, this study investigated 80 different spots of old trees, plant communities and forests, located in 11 cities and counties in Gyengnam Province and Jeonnam Province adjacent to the southern coast of Korea. To measure the health and actual maintenance conditions of old trees and plant communities objectively, the standard of judgment was established through the brain storming of experts. As a result of the field survey, out of all the old trees and plant communities that are not law-protected, this study selected old trees and plant communities that are in good health and likely to pass the standard of designating law-protected trees according to the Established Rule 574 of the Korea Forest Service Regulation. As for the plant community and old trees likely to be law-protected, this study judged that the torreya forest in Naneum Li, Namhae and old trees in 13 spots, in cluding so-called 'Couple Pine Tree' in Pyeongsa Li, Hadong, have a high possibility of being designated as a law-protected plant community and old trees. As for the species of old trees, there were 3 zelkova serrata trees, 3 celtis sinensis persoon trees, 2 pinus densiflora trees, 1 castanopsis cuspidata tree, 1 salix chaenomeloides tree and 1 machilus thunbergii tree found in the survey areas. Overall, this study judged that those old trees and plant communities require a national systematic maintenance by being designated as law-protected ones, and their values should be handed down to posterity as our forest cultural assets.

• Korean Journal of Plant Taxonomy
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• v.44 no.2
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• pp.91-99
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• 2014

Leaf anatomical study of Pinus thunbergii collected from 12 different coastal regions of Korea was conducted to understand the adaptive variation on leaf traits. Basic anatomical features are typical pine needle type with fibrous epidermis, 2-3 layered hypodermis, sunken stomata, monomorphic mesophyll, and well-represented bundle sheath. The bundle sheath surrounds a couple of vascular bundle separated by parenchyma bands. On the basis of their position, the resin ducts are of three types; external, medial and internal of the bundle sheath. The total number of resin ducts in all samples varies from 4 to 12. The stomata were found on stomatal bands throughout the leaf surface. Important dissimilarities observed on P. thunburgii leaf are the number and position of resin ducts and the number of stomata rows in leaf surface.

• Ocean and Polar Research
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• v.41 no.3
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• pp.159-168
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• 2019

Understanding the interaction between climate and the water cycle is critical especially in a drought sensitive region such as California. This study explored hydrologic changes in central and southern California in relation to the glacial-interglacial climate cycles over the last 30 thousand years. To do this, we reconstructed paleovegetation using plant wax carbon isotopic compositions (${\delta}^{13}C$) preserved in marine sediment cores retrieved from the central California continental shelf (ODP Site 1018) and Santa Barbara Basin (ODP Site 893A). The results were then compared to the existing sea surface temperature (SST) and pollen records from the same cores to understand terrestrial hydrology in relation to oceanographic processes. The Last Glacial was generally dry both in central and southern California, indicated by grassland expansion, confirming the previously suggested notion that the westerly storm track that supplies the majority of the precipitation in California may not have moved southward during the glacial period. Southern California was drier than central California during the Last Glacial Maximum (LGM). This drying trend may have been associated with the weakening of the California Current and northerly winds leading to the early increase in SST in southern California and decline in both offshore and coastal upwelling. The climate was wetter during the Holocene in both regions compared to the glacial period and forest coverage increased accordingly. We attribute this wetter condition to the precipitation contribution increase from the tropics. Overall, we found a clear synchronicity between the terrestrial and marine environment which showed that the terrestrial vegetation composition in California is greatly affected by not only the global climate states but also regional oceanographic and atmospheric conditions that regulate the timing and amount of precipitation over California.

• Journal of Microbiology and Biotechnology
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• v.31 no.11
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• pp.1526-1532
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• 2021

Suaeda australis, Phragmites australis, Suaeda maritima, Suaeda glauca Bunge, and Limonium tetragonum in the Seocheon salt marsh on the west coast of the Korean Penincula were sampled in order to identify the endophytes inhabiting the roots. A total of 128 endophytic fungal isolates belonging to 31 different genera were identified using the fungal internal transcribed spacer (ITS) regions and the 5.8S ribosomal RNA gene. Fusarium, Paraconiothyrium and Alternaria were the most commonly isolated genera in the plant root samples. Various diversity indicators were used to assess the diversity of the isolated fungi. Pure cultures containing each of the 128 endophytic fungi, respectively, were tested for the plant growth-promoting abilities of the fungus on Waito-C rice germinals. The culture filtrate of the isolate Lt-1-3-3 significantly increased the growth of shoots compared to the shoots treated with the control. Lt-1-3-3 culture filtrate was analyzed and showed the presence of gibberellins (GA₁ 2.487 ng/ml, GA₃ 2.592 ng/ml, GA₉ 3.998, and GA₂₄ 6.191 ng/ml). The culture filtrate from the Lt-1-3-3 fungal isolate produced greater amounts of GA₉ and GA₂₄ than the wild-type Gibberella fujikuroi, a fungus known to produce large amounts of gibberellins. By the molecular analysis, fungal isolate Lt-1-3-3 was identified as Gibberella intermedia, with 100% similarity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.6
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• pp.165-177
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• 2023

Field surveys were conducted at a total of 50 locations targeting naturalized plants on Ulleung-do. A total of 109 taxa were identified, including the list of naturalized plants in the preceding literature. The naturalized plants of Ulleung-do had a high proportion of Asteraceae, which appeared frequently in the habitat of the ruderal type. There were no naturalized plants that settled only on Ulleung-do, and all naturalized plants found on Ulleung-do first settled on the Korean Peninsula. This was proved by the high rates of epecophyten (90.8%) and the introduction period 2nd (70.6%). On the other hand, among ecosystem-disturbing species that have a great influence in the inland of the Korean Peninsula, Hypochaeris radicata and Rumex acetosella appeared in a limited area in Ulleung-do. On the other hand, Lapsana communis appeared in high density along the forest edge, requiring management of naturalized plants different from those in the Korean Peninsula. Naturalized plants on Ulleung-do showed a rapid increase in the 1990s after increased academic research, coastal road development, and other development projects. This highlights the necessity for continuous research on the pattern of naturalized plant occurrence after the completion of the Ulleung Airport, which is currently under construction.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.2
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• pp.67-72
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• 2010

In this study, the impact on the circulating water system has been analyzed due to an installation of helical turbine to develop hydro-kinetic energy at the discharge channel of the power plant. Numerical simulations of velocity and pressure variations have been performed when one set of $3.6\;m\;{\times}\;1.5\;m$ sized helical turbine is installed at the outlet of discharge culvert. In case of mean sea level, change of downstream water surface elevation does not affect upstream elevation of the weir because its propagation is blocked by the seal well weir. However in case of highest high water level, change of downstream elevation affects upstream elevation because flow pattern in discharge culvert becomes the full pipe flow with submerged weir. Although an unstable pressure change occurs in upstream of the weir during the intial 10 minutes after beginning of the discharge, it becomes stable after that time. In addition, a rise of water surface elevation by 0.2 m is observed but it is concluded that it hardly affects the safety of circulating water pump (CWP) although its required power is increased more or less. Therefore, the increase of required power of CWP needs to be considered for evaluation of the helical turbine applicability.