• Journal of Wetlands Research
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• v.9 no.2
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• pp.21-31
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• 2007

Estuarine wetland, where freshwater meets saltwater, is a transitional ecosystem that is valuable ecologically for a variety of reasons, such as feeding and breeding sites for birds, fish, and wildlife. However, research on the spatial distribution and temporal dynamics of estuarine wetlands in Korea is rare. As a fundamental basis for wetland conservation, this study quantified the wetlands in three major estuaries, and evaluated the temporal dynamics of the wetlands since the 1910s. In particular, this study classified the wetland types into mud flat, sand, and emergent-plant types, and estimated the change of each wetland type, using topographic maps produced in the 1910s, 1970s, and 2000s. The wetlands in both the Han and Youngsan River estuaries have declined since the 1910s, but the rate of wetland decline was relatively low before the 1970s, compared to that since the 1970s. The impact of human activities, such as the Youngsan Watershed Comprehensive Development Project and the construction of estuary barrages, has disrupted the estuary cycles and destroyed huge amounts of wetland in the Youngsan estuary. By contrast, estuarine wetlands have been preserved in the small Gahwa estuary, and provide a variety of habitats for plants and wildlife. A special management strategy for wetlands should be established as soon as possible.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.55-59
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• 2006

The objectives of this study, an analysis of the morphological characteristics among six provenances of a rare Rhododendron micranthum could be used for the conservation of gene resources and could provide information on superior trees selection. The following results were obtained. Approximately Mt.worak region showed larger values at petal character. On the other hand, Bonghwa region showed smaller values at petal character. Yeonha-ri region showed larger values at leaf character. On the other hand, Bonghwa region showed smaller values at leaf character. The results of principal component analysis (PCA) for morphological characteristics showed that the first for principal components(PC's) explained 41.6% of the total variation. From th third PC explained 81.5% of the total variation. The first PC was correlated with those characteristics that were mainly related to the Petal length (PL), Leaf length (LL) width (LW), Stigma length (SL). The second PC was correlated with the Petiole length (PTW), Anther length (AL). The third PC was correlated with the Flower pedicel length (FPL), Filament length (FL). Therefore, these characteristics was important to analysis of the variation for morphological characteristics among provenances of Rhododendron micranthum. Cluster analysis using single linkage method based on morphological characteristics showed that six provenances of Rhododendron micranthum could be clustered into three groups. Group I is Jicdong-ri, Group II is Mt.worak and Yeonha-ri, and Group III is Taeback, Bonghwa, and Samcheok. These results corresponded well with that of principal component analysis.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.205-213
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• 2005

This study was conducted to evaluate the response of the selected aquatic plants to sulfonylurea(SU)-herbicides, which have been used widely in rice-cultivating areas in Korea, and the possibility of using them as bio-indicator species for biodiversity conservation. The aquatic plants identified in Kangwon province where butachlor have been used extensively for many years were much more varied than those in Chonnam where SU-herbicides have been used extensively for many years. The growth responses of Monochoria korsakowii, Marsilea quadrifolia and Salvinia natans to sulfonylurea herbicides such as bensulfuron-methyl(BSM) and pyrazosulfuron-ethyl(PSE), were much more sensitive than those to butachlor and molinate. The $GR_{50}$ values of BSM and PSE for M. korsakowii, M. quadrifolia and S. natans were relatively very low when compared with those of butachlor and molinate. The number of internode and dry weight of M. quadrifolia which was exposed to herbicides runoff from rice fields were seriously affected. The acetolactate synthase(ALS) activities of M. quadrifolia sensitively inhibited by BSM and PSE were, and $I_{50}$(Inhibition 50%) were 5.6 and 2.1 nM, respectively.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.107-120
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• 2012

This study was carried out to illiminate the diversity of vascular plants by making list of rheophyte and hydorphyte plants at Yugu stream. This study was conducted from Aug., 2009 to Sept. 2010 at 7 points. Based on the voucher specimens, vascular plants from investigated areas were 88 families 229 genera 290 species 3 subspecies 30 varieties 5 forms, totally 328 taxa. Korean endemic plants were 3 species such as Forsythia koreana (Rehder) Nakai (planted) and Paulownia coreana Uyeki (planted), and Weigela subsessilis (Nakai) L.H. Bailey. The rare and endangered plants were designated by Korea Forest Service were 4 taxa, such as Penthorum chinense Pursh, Acorus calamus L., Lilium callosum Siebold & Zucc. and Iris ensata var. spontanea (Makino) Nakai. Floristic special plants were totally 26 taxa, which were grade V of 2 taxa, grade IV of 2 taxa and grade III of 9 taxa. Naturalized plants were 27 taxa, that was 8.3% of whole discovered vascular plants in this area. Even naturalized plants has not influence on the vegetation of Yugu stream. Since village was composed along the stream and the roads and banks were linked, naturalized plants were flowed continuously into this region. So, strategy of the conservation for this region should be designed. Based on flora, 3 types of group were discriminated such as main stream type (4 points), branch stream type (2 points) and reservior type (1 point). Each group has difference in composition of plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.4
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• pp.47-71
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• 2009

The resource plants of northern region in Gapyeong-gun were investigated 7 times from Apr. 2007 to Oct. 2007. In the result of survey, the flora of this area, depend on voucher specimens, consist of 480 taxa totally; 94 families, 286 genera, 412 species, 4 subspecies, 52 varieties and 12 forms. The Resource plants in this area were categorized by their use into edible 177, pasturing 136, medicinal 124, stainable 69, ornamental 133, afforest 24, timber 10, fiber 6, industrial 2 taxa and unknown use plants 72, respectively. There were remarkable plants such as 14 taxa of Korean endemic plants, 85 taxa of specific plants which were designated by the Ministry of Environment, and 12 taxa of rare and endangered plants of Korea Forest Service. Furthermore, 22 taxa of naturalized plants 4.6% were also observed in this area and Urban Index (UI) was 8.2%. The vegetation status of investigated area was comparatively well conserved, but the degree of UI could be increased rapidly by the climbers, development of forest road. Therefore, the systems for conservation need to prepared for the effective management of forest, and the special plans need to control the number of climbers and visitors.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.236-241
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• 2013

Introduction of rye living mulch in soybean production is important for labor-saving and reduction of herbicide usage for weeding by weed suppression and for soil conservation by mulching of rye. Soybean and rye were row-planted and broadcasted simultaneously at different planting times (May 15, May 25, June 5) and row widths (35 and 70 cm) in 2010, different soybean cultivars (Daepoong, Singi) and planting times (May 15 and June 1) in 2011, respectively, and investigated weed occurrence, early growth and yield of soybean. Acalypha australis, which is known to herbicide-resistant weed, could be controlled ecologically by rye living mulch. Occurrence of Acalypha australis was controlled effectively also by mixture of alachlor and linulon at no mulch in 2011. Early growth amount of soybean plant per area was increased by narrow row width (35 cm) at rye living mulch, which was helpful in the control of weeds, but grain yield of soybean with narrow row was decreased compared to conventional row width (70 cm) at the planting in early June. It is concluded that soybean planting as row width 70 cm in early June is proper at simultaneous planting with rye.

• Journal of Life Science
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• v.26 no.12
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• pp.1446-1457
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• 2016

Wetlands exhibit intermediate characteristics of both terrestrial and aquatic ecosystems, and the biodiversity is rich in these unique biological habitats. The symbiotic relationships between plants and fungi that inhabit these wetlands play an important role in natural resource management, biodiversity, and conservation. Accordingly, the mujechi, having academic value for the study of the natural environment, was investigated in terms of genetic diversity of endophytic fungi, which inhabit the roots of wild plants. The internal transcribed spacer (ITS) region was amplified to identify fungal strains. In total, 226 strains were isolated and categorized into three phyla, seven classes, 10 orders, 22 families, and 31 genera. In plants by endophytic fungi were classified in Isachne globosa (Ig) to 19 genera, Scirpus karuisawensis (Sk) to 11 genera, Utricularia racemosa (Ur) to 19 genera, and one incertae sedis, Eriocaulon decemflorum (Ed) to 11 genera. The fungal taxa was identified the genera Acephala (19.9%), Tolypocladium (16.3%), Neopestalotiopsis (11.5%), and Perenniporia (7.1%). The fungal group isolated from Isachne globosa (Ig) grew the largest number of isolated fungal strains. After comprehensive evaluation, the endophytic fungal group from Utricularia racemosa (Ur) ranked highest in diversity analyses. From the roots of wild plant in mujechi-neup, it confirmed the distribution and diversity of endophytic fungi. This study provides the basic data to understand fungal community structure in peat wetlands.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.26-34
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• 2015

Korean Poaceae includes approximately 80 species of the agricultural weeds. Precise species identification is the first step for more effective weed management in the agricultural fields. However, the identification of species in Poaceae is not easy without the assistance of taxonomists or identification experts although they are relatively easy to distinguish from the plants of the other family by the unique characteristics of caryopsis. Thus, DNA barcode was suggested as an alternative powerful technique for species identification by using short sections of DNA from a specific region of the genome. Two standard barcode markers of vascular plants, chloroplast rbcL and matK, and a supplementary nuclear ribosomal Internal Transcribed Spacer (ITS) region were used for barcode of major Korean Poaceae weeds, 403 individuals of 84 taxa. All the barcode markers revealed a good level of sequencing success with the lowest 73.7% for matK and the highest 88.8% for rbcL. The barcode sequences were deposited to the National Center for Biotechnology Information (NCBI) database for public use. Combined matK and ITS showed very high resolving power with 92.9%. Besides the identification of weeds for weed managment, the generated DNA barcode data could be used for many other applications such as rapid biodiversity assessment and conservation prioritization.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.231-242
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• 2011

Recently, the green spaces in the urban areas were greatly reduced due to urbanization and industrialization. As urban structures such as roads and buildings are built, the amount of impervious area within a watershed increases. High impervious surfaces are the common causes of high runoff volumes as the soil infiltration capacity decreases and the volume and rate of runoff increase thereby decreasing the groundwater recharge. These effects are causing many environmental problems, such as floods and droughts, climate change, heat island phenomenon, drying streams, etc. Most cities attempted to reduce sewer overflows by separating combined sewers, expanding treatment capacity or storage within the sewer system, or by replacing broken or decaying pipes. However, these practices can be enormously expensive than combined sewer overflows. Therefore, in order to improve these practices, alternative methods should be undertaken. A new approach termed as "Low Impact Development (LID)" technology is currently applied in developed countries around the world. The purpose of this study was to effectively manage runoff by adopting the LID techniques. Small Constructed Wetland(Horizontal Subsurface Flow, HSSF) Pilot-scale reactors were made in which monitoring and experiments were performed to investigate the efficiency of the system in removing pollutants from runoff. Based on the results of the Pilot-plant experiments, TSS, $COD_{Cr}$, TN, TP, Total Pb removal efficiency were 95, 82, 35, 91 and 57%, respectively. Most of the pollutants were reduced after passing the settling tank and the vertical filter media. The results of this study can contribute to the conservation of aquatic ecosystems and restoration of natural water cycle in the urban areas.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.45-62
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• 2010

Zero plane displacement (d) is the elevated height of the apparent momentum sink exerted by the vegetation on the air. For a vegetative canopy, d depends on the roughness structure of a plant canopy such as leaf area index, canopy height and canopy density, and thus is critical for the analysis of canopy turbulence and the calculation of surface scalar fluxes. In this research note, we estimated d at the Gwangneung coniferous forest by employing two independent methods of Rotach (1994) and Martano (2000), which require only a single-level eddy-covariance measurement. In general, these two methods provided comparable estimates of $d/h_c$ (where $h_c$ is the canopy height, i.e., ~23m), which ranged from 0.51 to 0.97 depending on wind directions. These estimates of $d/h_c$ were within the ranges (i.e., 0.64~0.94) reported from other forests in the literature but were sensitive to the forms of the nondimensional functions for atmospheric stability. Our finding indicates that one should be careful in interepreation of zero plane displacement estimated from a single-level eddy covariance measurement that is conductaed within the roughness sublayer.