• Applied Microscopy
• /
• v.44 no.1
• /
• pp.1-7
• /
• 2014

The spermatogenesis of Siamese fighting fish, Betta splendens, belongs to Osphronemidae was investigated by light and electron microscopic observations. In primary spermatocyte stage, the nucleus was comparatively large ellipsoidal, and mitochondria showed a marked development in cytoplasm. In secondary spermatocyte stage, the germ cells were smaller than that of primary spermatocytes. The nucleus was a spherical shape and intercellular space was formed between germ cells. In spermatid stage, the early spermatids were not much different from a secondary spermatocyte. But, the chromatin condensation was occurred from the outside to the inside. The nucleus was more condensed. Intracellular space was larger than early spermatid. The mitochondria were rearranged in a middle piece, and occupied about half of the head part in early sperm. In sperm stage, the head of mature sperm was a spherical shape and had no acrosome. The flagellum was showed the typical 9+2 array of microtubules. Also, the tail of sperm had no lateral fins and outer coarse fibers. These ultrastructural characteristics can be used in classification of species.

• 보존과학연구
• /
• s.13
• /
• pp.96-112
• /
• 1992

We made biological investigation on the conservational environment of collections in the Ho Am museum. Annual average temperature and relative humidity outside the museum were $11. 0∼11.7^{\circ}C$ and 64.8∼74.4% respectivey. On the other hand, average annual temperature and relative humidity inside the main storage were $19.1∼20.1^{\circ}C$ and 53.0∼63.4%. We isolated fungi and classified into 8 genus 13species fungi and selected four fungi having high cellulotic activity such as Alternaria brassicae KCPRI 9202, Aspergillus niger KCPRI 9205, Aspergillusversicolor KCPRI 9206, Penicillium adametzi KCPRI 9208. These fungi were examined on the posibility of collections being damaged under current conservation al environment in the museum. KCPRI 9208 was non-tonophilic fungus and other were facutative tonophilic fungi. These showed maximal cellulotic activity of enzymeshaking culture at pH 5.0∼5.5 for 4 and 5 days. In proprtion to the period damaged, cellulase activity for paper damaged artifically with growing worse of material. As are sult cellulotic activity by fungi increased.

• Tuberculosis and Respiratory Diseases
• /
• v.78 no.4
• /
• pp.416-418
• /
• 2015

Mycobacterium shinjukuense is a novel species of nontuberculous mycobacteria (NTM) that was first reported in Japan in 2011. It is a slow-growing NTM pathogen that can cause chronic pulmonary infections. There are only a few reported cases of M. shinjukuense infections, all of which are from Japan. We reported a case of chronic lung disease caused by M. shinjukuense. The organism was identified by 16S rRNA, rpoB, and hsp65 gene sequencing. To the best of our knowledge, this was the first confirmed case of lung disease caused by M. shinjukuense outside of Japan.

• Korean Journal of Microbiology
• /
• v.52 no.2
• /
• pp.226-229
• /
• 2016

The growth of two different fungal species, human pathogenic Cryptococcus neoformans and plant pathogenic Alternaria alternata were inhibited by a chitinase (Chi2) expressed in the autolysing tissue of Coprinellus congregatus. The cell wall thickness was reduced (up to 32%) in C. neoformans compared with that of normal cell, and polysaccharide fibers located outside of the cell wall were also severely removed. The hyphal growth of A. alternata on agar plate was stopped by the enzyme. The allergic inflammation induced by A. alternata was reduced by the enzyme reaction when compared with untreated control in a mouse model.

• Fisheries and Aquatic Sciences
• /
• v.24 no.3
• /
• pp.121-128
• /
• 2021

The variations of morphological features, density and biomass of vegetative shoots and characteristics of reproductive shoots of Zostera caespitosa were examined in Tongyeong, Korea. Morphological features such as leaf length, width and sheath length of Z. caespitosa showed significant seasonal variation (p < 0.001). The highest aboveground value was recorded in late spring to summer and the lowest value in winter. Density and biomass also showed seasonal variations. Annual average shoot density and biomass of Z. caespitosa were recorded as 1,223.4 leaf m^-2 and 5,956.9 g w.w.m^-2, respectively, and had the highest value in June and lowest values in November and January. Reproductive shoots were observed from April (13℃) to June (21℃). Pistils erected outside sheath, anther dehiscing and small embryos were found in April. Mature fruit and released seeds were found in May and June. These results suggest that this species had a high growth rate in late spring and early summer (15℃-20℃). Reproductive shoots of Z. caespitosa may initially appear at about 10℃ in spring and seed have been released at about 20℃ in fall.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.2 no.4
• /
• pp.285-292
• /
• 2021

We investigated habitat use and home range of a rescued and released white-naped crane using GPS tracking technology in Cheorwon, South Korea, from October 2016 to March 2017. Four types of roosting sites were identified: frozen reservoirs, paddy fields, rivers, and wetlands. Upon arrival, the white-naped crane preferred wetlands in the Demilitarized Zone (DMZ). In late wintering season, it showed a tendency to change main roosting sites in the following order: rice paddies, rivers, and frozen reservoirs. Among 14 sleeping places, Civilian Control Zone (CCZ) with various type of available habitats was more preferred than the DMZ. Places outside of CCZ were rarely used due to anthropogenic disturbances during the night. The tracked white-naped crane widely chose daytime feeding sites while moving around all over rice paddies in the CCZ. Mean diurnal movement distance was 10.5 km with a maximum of 24.8 km. Its home range measured with Minimum Convex Polygon (MCP) and Kernel Density Estimation (KDE) was 172.30 km² with MCP, 159.60 km² with KDE 95%, 132.48 km² with KDE 90%, and 42.45 km² with KDE 50%. All estimated values of home ranges were higher in the early and later winter than those in the middle period.

• Korean Journal of Plant Taxonomy
• /
• v.53 no.2
• /
• pp.79-101
• /
• 2023

Following recent taxonomic, distributional, and nomenclatural revisions, an updated checklist of endemic plants on the Korean Peninsula is needed. This study provides an updated checklist of vascular plants endemic to the Korean Peninsula and describes their distribution within administrative provinces. The revised checklist includes 373 endemic taxa (304 species, six subspecies, 49 varieties, and 14 nothospecies) from 179 genera and 64 families, representing 9.5% of the total native flora of the Korean Peninsula. Asteraceae (41 taxa), Ranunculaceae (29 taxa), Liliaceae s.l. (24 taxa), and Rosaceae (22 taxa) were the most widely represented families. Compared with the most recent checklist published in 2017, 39 taxa were excluded from the checklist; one taxon was excluded because it did not have a valid published name, seven taxa were excluded because their natural habitats extended to neighboring countries, four taxa were excluded because they were treated as a rank form, and 27 taxa were excluded because they had been identified as heterotypic synonyms of taxa distributed outside of the Korean Peninsula. Fifty-two new taxa were included based on the literature. This checklist will help to focus conservation efforts and provide a framework for research, protection, and policy implementation related to these endemic taxa.

• Journal of Forest and Environmental Science
• /
• v.39 no.4
• /
• pp.235-245
• /
• 2023

Forest fuel moisture content is a crucial factor influencing the combustion rate and fuel consumption during forest fires, significantly impacting the occurrence and spread of wildfires. In this study, meteorological data were gathered using a meteorological measuring device (HOBO data logger) installed in the south and north slopes of Kangwon National University Forest, as well as on bare land outside the forest, from November 1, 2021, to October 31, 2022. The objective was to analyze the relationship between meteorological data and fuel moisture content. Fuel moisture content from the ground cover on the south and north slopes was collected. Fallen leaves on the ground were utilized, with a focus on broad-leaved trees (Prunus serrulata, Quercus dentata, Quercus mongolica, and Castanea crenata) and coniferous trees (Pinus densiflora and Pinus koraiensis), categorized by species. Additionally, correlation analysis with fuel moisture content was conducted using temperature (average, maximum, and minimum), humidity (average, minimum), illuminance (average, maximum, and minimum), and wind speed (average, maximum, and minimum) data collected by meteorological measuring devices in the study area. The results indicated a significant correlation between meteorological factors such as temperature, humidity, illuminance, and wind speed, and the moisture content of fuels. Notably, exceptions were observed for the moisture content of the on the north slope and that of the ground cover of Prunus serrulata and Castanea crenata.

• Journal of Environmental Impact Assessment
• /
• v.26 no.4
• /
• pp.272-289
• /
• 2017

This study analyzed the status of the naturalized plants in islands in Jeollanamdo from an island biogeographic perspective. As a result of a floristic analysis at 47 inhabited islands and 194 uninhabited islands, 30 families and 134 species naturalized plants are reported. The most commonly occurring naturalized plant from 141 islands was Rumex crispus. The average number of naturalized plants by islands is 20.6 species (${\pm}14.22$) at the inhabited islands and 3.7 species (${\pm}3.89$) at the uninhabited islands. Presence of fifty nine naturalized species at Geumodo in Yeosu-si is the largest in number. The naturalization ratio, which is the ratio of naturalized plants to native plants, is 7.66% (${\pm}3.96$) in the inhabitable islands and 4.97% (${\pm}3.70$) in the uninhabitable islands. The naturalization ratio among islands of the West Sea in Jeollanam-do is 5.92% (${\pm}4.49$), and it is higher than 4.96% (${\pm}2.15$) in islands in the South Sea. Especially, the naturalization ratio at the inhabitable islands, i.e., 8.39% (${\pm}4.37$) at the islands of the West Sea is higher than 5.80% (${\pm}1.41$) at islands in the South Sea. The naturalization ratio of naturalized plants at the islands shows positive correlation with the size of the island (r=0.412, p<0.01), but the correlations with distance from the mainland and altitude above sea level are not significant. Eight ecosystem disturbing species designated by law are reported, and each species shows distinct distributional ranges. The regional differences in the number of naturalized plant species seem to be a result of the complex reflection of natural and human environmental factors, such as the degree of traffic between mainland and islands, degree of cultivation activities, along with the physical environmental differences. Since islands have limited habitats and resources, islands could be more vulnerable to the incoming species from outside, and environmental changes than mainland. Therefore, continuous monitoring and management against the naturalized plants in islands are needed.

• Korean Journal of Environment and Ecology
• /
• v.27 no.6
• /
• pp.676-689
• /
• 2013

This study is to understand the current situation of Wonju Stream, which flows through Wonju, Kangwon-do, and Seom River, the national river located outside of Wonju, by investigating all river areas using biotope type. Also, this research looked into the relationship between biotope and appearance of wild birds by investigating the location of their appearance. Biotope groups are 'scale', 'shape', and 'landscape'. And, biotope types are 'moisture', 'physical environment', and 'existence of vegetation'. Biotope subtypes are 'river area', 'physical environment', 'vegetation type', and 'usage of land'. Seom River is classified as 21 different sections, and Wonju Stream is classified as 19 different sections. Wild birds are investigated on breeding season, which was January and May of 2008. By marking each bird's location of appearance, it figured out properties of biotope according to the location of bird's appearance. 31 species, 795 birds in spring were founded, and 49 species, 4,348 birds are founded in winter at Seom River area. Also, 34 species, 427 birds in spring, and 33 species, 3,442 birds are founded in winter at Wonju Stream area. In winter, 26 species, 547 birds, and in spring, 12 species, 72 birds at natural river with estuaries in confluence of Seom River area are founded. Also, 34 species, 1412 birds in winter, and 24 species, 341 birds in spring are founded at natural river with estuaries and wetland plants. This means that because agricultural rivers have wide river width, slow flow speed, and many different types of biotope, these rivers can be good habitats for wild birds. The precise investigations and classifications of biotope, which especially are hard for linear rivers, were done to understand the whole and current situation of rivers. Furthermore, the data that shows the locations of wild birds can basically be used for a recovery of biological habitats, a constructing of ecological streams, a river-maintenance, and an enhancement of biodiversity of Wonju. Also, because the types of biotope are altered by rain, a continuous monitoring for maintaining ecosystem of rivers are highly needed.