• Journal of fish pathology
• /
• v.33 no.1
• /
• pp.7-14
• /
• 2020

A disease that manifested severe anemia of the gills occurred in the olive flounder (Paralichthys olivaceus), which was cultured for 5-6 months with a recirculation water system in the laboratory. Microscopic observations showed immature parasite in the gills and mature adults in the oral cavity. The matured parasite was 5.60-9.32 (7.42) mm in total length, with 4 pairs of clamps on the pedunculated haptor, which was separated from the body proper by a long isthmus. From the morphological observations of the larvae, it was identified as Neoheterobothirum hirame belonging to the monogenea. The average hematocrite of infected fish was 10.3 ± 2.8%, significantly lower than that of normal flounder 31.4 ± 4.2%. Histopathologically, fish infected with N. hirame exhibited reduced numbers of erythrocytes in blood vessels of the gill filament and lamellae, reduced red pulp area of the spleen, and hepatocyte atrophy. From the above results, the cause of severe anemia in olive flounder was identified as N. hirame infection. This study shows an example where the growth of pathogens can be a problem in the recirculation system due to low water exchange rate.

• Korean Journal of Plant Resources
• /
• v.24 no.5
• /
• pp.489-498
• /
• 2011

This study was carried out to investigate the distribution status and urbanization index of the naturalized plants. For this purpose, 7 cities and counties in the eastern area of Jeollanamdo were selected and investigations were conducted on a total of 14 sites, during the period of March 2006 to November 2008. The naturalized plants were identified as 123; 22 families, 75 genera, 118 species, and 5 varieties. As for the urbanization index, Suncheon city had the highest level of urbanization (33.45%) and Gurye county the lowest level of urbanization (20.21%). Classification families were as follows: Compositae 40 kinds (30.1%) Gramineae 17 kinds (12.8%) and Leguminosae 14 kinds (10.5%). Major communities of naturalized plants consisted of 20 communities including Erigeron annuus community, Erigeron canadensis community, Alnus firma community, Amorpha fruticosa community, Oenothera odorata community, Bidens frondosa community, Coreopsis tinctoria community, Ambrosia artemisiifolia var. elatior community etc. Invasive naturalized plants consisted of 5 taxa: Ambrosia artemisiifolia var. elatior, Ambrosia trifida, Eupatorium rugosum, Paspalum distichum var. indutum and Paspalum distichum. The distributional characteristics of naturalized plants were divided on the basis of six areas associated with ecological characteristics of a habitat.

• Journal of agriculture & life science
• /
• v.50 no.1
• /
• pp.125-136
• /
• 2016

The Korea Forest Service(KFS) has been initiating restoration activities of ridgeline in damaged and fragmented areas of Baekdudaegan since 2011. Completed project in Ihwaryeong, Yuksimnyeong & Beoljae(2012; 2013) were selected as sites for this study. The changes in microclimate condition, vegetation composition and soil properties between project sites and adjacent stands were compared to evaluate the effect of restoration at early stage(after 2years). Pinus densiflora was planted mainly for these restoration sites, however Robinia pseudoacacia and Alnus sibirica invaded the area two years after the restoration activities. Ihwaryeong showed the most changes in understory vegetation among the study sites. Exotic species, such as Ambrosia artemisiifolia, Oenothera odorata, Erigeron annuus, and Coreopsis tinctoria invaded Ihwaryeong, and the dominance have invaded currently. It resulted from the poor survival rate of trees and high difference in microclimate wherein there's an increased temperature and decreased humidity in both restored sites and adjacent stands. In addition, it is also caused by poor soil chemical property, especially pH and organic matter content due to lack of humus layer and its accumulation, compared to adjacent forest soil in restored sites. Significant difference on chemical soil property was observed between restored sites and adjacent forest but no significant difference was observed after two years of restoration. Ecological monitoring is needed to understand the ecological changes after restoration and to establish a long-term management strategy.

• Korean Journal of Environment and Ecology
• /
• v.36 no.2
• /
• pp.118-138
• /
• 2022

This study was conducted to identify the vegetation structure of major vegetation by region and elevation in the subalpine zone of Seoraksan National Park and prepare an inventory of flora. We reviewed the results of the previous subalpine studies and, through a preliminary survey, determined that the first appearance point of subalpine vegetation was about 800 m based on the south. Then we conducted a site survey by installing a total of 77 plots, including 12 plots on the northern Baekdamsa-Madeungnyeong trail (BD), 13 plots on the west Hangyeryeong-Kkeutcheong trail (HG), 13 plots on the east side of Sinheungsa-Socheongbong trail (SA), and 39 plots in the southern Osaek-Kkeutcheong, Osaek-Daecheongbong trail (OS), in an interval of 50 m above sea level. The analysis classified 7 communities, including Qercus mongolica-Abies holophylla-Acer pseudosieboldianumcommunity, Q. mongolica-Tilia amurensiscommunity, Q. mongolica-Pinus koraiensiscommunity, Q. mongolica-A. pseudosieboldianumcommunity, Betula ermanii-A. nephrolepiscommunity, P. koraiensis-A. nephrolepiscommunity, and mixed deciduous broad-leaf tree community according to the species composition based on the appearance of the major subalpine plants such as Quercus mongolica, Betula ermanii, and Abies nephrolepis, region, and elevation. 10.68±2.98 species appeared per plot (100 m²), and 110.87±63.89 individuals were identified. The species diversity analysis showed that the subalpine vegetation community of Seoraksan National Park was a mixed forest in which various species appeared as important species. Although there was a difference in the initial elevation for the appearance of major subalpine plants by region, they were distributed intensively in the elevation range of 1,100 to 1,300 m. In the Seoraksan National Park, 322 taxa, 83 families, 193 genera, 196 species, 1 subspecies, 26 varieties, and 4 forms of vascular plants were identified. One taxon of Trientalis europaeavar.arcticawas identified as the protected species. The endemic plants were 19 taxa, and 58 taxa were identified as subalpine plants.

• Korean Journal of Plant Resources
• /
• v.21 no.1
• /
• pp.73-82
• /
• 2008

The resource plants of the Mt. Geonji was listed 354 taxa; 92 families, 242 genera, 303 species, 48 varieties and 3 forms. 354 taxa listed consists of 205 taxa of edible plants(57.1%),234 taxa of medicinal plants(65.2%), 167 taxa of ornamental plants(46.5%) and 218 taxa of the others(60.7%). Specific plant species by floral region were total 22 taxa; Trapella sinensis var. antennifera in class IV, Iris ensata var. spontanea in Class II, 16 taxa(Salix glandulosa, Alnus hirsuta, Chrysosplenium flagelliferum, Mallotus japonicus, Ilex macropoda, Grewia biloba var. parviflora, Vaccinium oldhami, Lysimachia barystachys, Fraxinus mandshurica, etc.) in class I. The naturalized plants in this site were 12 families, 23 genera, 28 species, 2 varieties, 30 taxa(Bromus unioloides, Phytolacca americana, Oenothera erythrosepala, Ipomoea hederacea var. hederacea, Aster pilosus, Erechtites hieracifolia) and naturalization rate was 8.5% of all 354 taxa vascular plants. Wild plants disturbing ecosystem like Solanum carolinense and Ambrosia artemisiifolia var. elatior have been increasing. So, it needs continuing control and conservation measures on the plant ecosystem.