• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.171-175
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• 2000

The ultrastructures of germinal cells of male marsh clam, Corbicujar lena were studied. The mature sperm was primitive type, consisting of head, middle piece and tail. The mature sperm was whip-shaped and its head was divided into two parts; the acrosomal part shaped long hollow cone about $3{\mu}m$ in length and the sperm nuclear part shaped a long stick about $9\;{\mu}m$ in length. The posterior part of the sperm nuclear projected to centriole, The middle piece of the sperm-nuclear had four mitochondria and two centrioles. The sperm tail part had the 9+2 microtubular arrangement known as a typical pattern, During spermiogenesis, chromatin within sperm nuclear became fiberic materials by condensation.

• Journal of Korea Water Resources Association
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• v.33 no.4
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• pp.483-493
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• 2000

Two dimensional finite element model, RMA, is used to simulate flood inundation phenomena from main channel to floodplain. The marsh porosity method allows finite elements to simulate gradual transition between wet and dry states. The model is applied to prismatic trapezoidal channel to test the applicability of wetting and drying. The floodwave in a river which meanders through a floodplain is also analyzed. The short-circuiting effects, in which the flow leave the meandering main channel and takes a more direct route on the floodplain, are analyzed with various sinuosity factor and roughness coefficients. Finally, the model is applied to the midstream of the Keum River. Wet/dry calculation can simulate the various discharge condition with the same finite element networks.

• The Korean Journal of Ecology
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• v.11 no.1
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• pp.1-15
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• 1988

Studies on species compostion, promary production of benthic algal assemblage were carried out along a channel of the salt marsh near Inch'on, Kyonggi Bay, Korea. Possible biological, physical and KDICical factors controlling the aglal assemblage were also examined. The oveall diatoms were encountered one hundred and thirty-seven taxa, of which the dominant species were Paralia sulcata and Cymatosira belgica. These two species accounted for 32.6% relative abundance throughout the study period. Diatom taxa had no clear seasonal pattern in abundance analysis. But at the algal blooming period in spring, euglenoids occurred with a high abundance. The chlorophyll a content of benthic algae showed definite seasonal pattern. The algal biomass of the appeared to influence the spatial fluctuation in the algal biomass of the channel was regulated primarily by water content of sediment. Grazing by zoobenthos apperaed to influence the spatial fluctuation in the algal biomass of the sediment surface. The algal photosynthesis was measured in the laboratory with oxygen method. Photo-synthetic rate was independent of the temperature under the lower irradiance. The gross production from March to November was estimated to be 190g C/m2 at the channel slope. Photosynthetic efficiency was 0.37% on the basis of the photosyntherically active radiation for the study period.

• The Korean Journal of Ecology
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• v.11 no.4
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• pp.175-192
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• 1988

The coastal vegetation of the southwestern coast of Korea was surveyed by the Braun-Blnquet's phytosociological sKDICe and its soil properties were also determined. Comparing with the coastal vegetation of Korea, Japan and Europe, the vegetation of this area could be classified into as follows; A. Thero-Salicornietea R. Tx. 1954(Salicor-nietum herbaceae assoc. nov.). B. Thero-Suaedetea Rivas Martwez 1979 (Suaedetum japonicae Miyawaki et Ohba 1966, Suaeda maritima commuity, Atriplici-Suaedetum maritimi Miyawaki et Ohba 1965, Suaeda asparagoided community) C. Asteretea tripolium Westhoff et Beeftink 1962 (Zoysietum sinice Ohba, Miyawaki et Tx. 1973, Limonietum tetragoni Miyawaki et Ohba 1969, Artemisietum scopariae assoc. nov., Aster tripolium community, Atriplex, gmelini community) D. Phragmitetea Tx. et Prsg. 1942 (Triglochietum maritimae assoc. nov., Carcetum scabrifoliae Miyawaki et Ohba 1969, phragmites communis community, Pyaceluretum latifolii Miyawaki et Okuda 1972, Scirpus fluviatilis community) E. Salsoletea komarovil Ohba, Miyawaki et Tx. 1973(Salsola komarovi community) F. Glehnietea littoralis ohba, Miyawaki et Tx. 1973(Caricetum pumilae assoc. nov., Meserschmidia sibirica community, Lysimachia mauri-tiana community Ishaemum anthephoroides community, Elymus mollis commuity, carex kobomugi community, Ixeris repens community) G. Viticetea rotundifoliae Ohba, Miyawaki et Tx. 1973 (Imperato cylindricae-Viticetum rotundifoliae ohba, Miyawaki ex Tx. 1973) and Opuntia ficus-indica var. saboten community. Among the soil properties, water potential seems to be one fo the most important factor on the distribution of the coastal plant community and it might be highly affected by water content in sand and salinity in low marsh.

• Korean Journal of Remote Sensing
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• v.25 no.4
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• pp.383-389
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• 2009

The main objective of the research is a feasibility study on the intertidal zone using a X-band radar satellite, TerraSAR-X. The TerraSAR-X data have been acquired in the west coast of Korea where large tidal flats, Ganghwa and Yeongjong tidal flats, are developed. Investigations include: 1) waterline and backscattering characteristics of the high resolution X-band images in tidal flats; 2) polarimetric signature of halophytes (or salt marsh plants), specifically Suaeda japonica; and 3) phase and coherence of interferometric pairs. Waterlines from TerraSAR-X data satisfy the requirement of horizontal accuracy of 60 m that corresponds to 20 cm in average height difference while current other spaceborne SAR systems could not meet the requirement. HH-polarization was the best for extraction of waterline, and its geometric position is reliable due to the short wavelength and accurate orbit control of the TerraSAR-X. A halophyte or salt marsh plant, Suaeda japonica, is an indicator of local sea level change. From X-band ground radar measurements, a dual polarization of VV/VH-pol. is anticipated to be the best for detection of the plant with about 9 dB difference at 35 degree incidence angle. However, TerraSAR-X HH/TV dual polarization was turned to be more effective for salt marsh monitoring. The HH-HV value was the maximum of about 7.9 dB at 31.6 degree incidence angle, which is fairly consistent with the results of X-band ground radar measurement. The boundary of salt marsh is effectively traceable specifically by TerraSAR-X cross-polarization data. While interferometric phase is not coherent within normal tidal flat, areas of salt marsh where the landization is preceded show coherent interferometric phases regardless of seasons or tide conditions. Although TerraSAR-X interferometry may not be effective to directly measure height or changes in tidal flat surface, TanDEM-X or other future X-band SAR tandem missions within one-day interval would be useful for mapping tidal flat topography.

• Journal of Life Science
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• v.22 no.7
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• pp.970-980
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• 2012

Native halophytes, such as Suaeda maritima, Limonium tetragonum, S. japonica, Zoysia sinica, and Phragmites australis were collected from the Muan salt marsh. Ninety endophytic fungi were isolated from the roots of the collected halophytes. Molecular insights inferred by internal transcribed spacer containing ITS1, 5.8s, and the ITS2 region showed that all the fungal strains belong to ten orders, i.e., Capnodiales (4.44%), Cystofilobasidiales (1.11%), Dothideales (3.33%), Eurotiales (53.33%), Glomerellales (3.33%), Hypocreales (8.89%), Mucorales (1.11%), Pleosporales (15.56%), Sordariales (1.11%), and Trichosphaeriales (1.11%). The rest (6.67%) of all fungal isolates were not identified. Ninety fungal strains were confirmed at the genus level, containing Acremonium, Alternaria, Aspergillus, Aureobasidium, Cephalosporium, Chaetomium, Cladosporium, Colletotrichum, Cryptococcus, Didymella, Dothideomycete, Emericellopsis, Epicoccum, Eupenicillium, Fusarium, Gibberella, Gongronella, Macrophoma, Microsphaeropsis, Nigrospora, Paecilomyces, Paraconiothyrium, Penicillium, Phaeomyces, Phoma, Pleosporales, Purpureocillium, and Talaromyces. Of all the endophytic fungi identified from the various halophytes, Aspergillus and Penicillium of Eurotiales had the highest abundance.

• The Korean Journal of Ecology
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• v.24 no.2
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• pp.101-109
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• 2001

We created an environmental forest on the basis of ecological design around the incineration plant of Jindo Engineering and Construction Co., Ltd., which is located in Jeongwang-dong, Siheung-si, Kyunggi-do. To get ecological information of this site, physico-chemical properties of soil on salt marsh, which is located close to the syudy site and of forest soil transported from other sites for ecological restoration were analyzed. Texture of salt marsh and transported soils were loam and sandy loam, respectively. pH, organic matter, T-N, available P, and exchangeable K and Na contents of salt marsh and transported forest soils were 6.7 and 5.4, 4.1 and 0.4%, 1.0 and 0.3mg/g, 46.7 and 6.8ppm, 521 and 207ppm, and 3.8 and 0.5mg/g, respectively. Introduced plants were selected among the dominant species of forests and the species composing the potential natural vegetation around the present study site. Those plants were selected again by considering the tolerances to air pollution and to salt, and their availability. Selected trees were Pinus thunbergii, Sophora japonica, Celtis sinensis, Quercus aliena, Q. serrata, Q. dentata, and Q. acutissima. Selected sub-trees were Albizzia julibrissin, Koelreuteria poniculata, and Styrax japonica and shrubs were Rhododendron yedoense var. poukhanense, R. mucronulatum, Callicarpa japonica, Euonymus alatus, E. japonica, and R. schlippenbachii. On the other hand, introduction of herbs was not considered except for Liriope platyphylla, which was ornamentally planted in one site. Planting bed of mound type was adopted to provide the fine drainage system. Mound was designed to furnish litter, A, B, and C layers simuating the profile of forest soil. Slope of mound was mulched by rice straw of 2cm in thickness to prevent for sliding of litter and soil in cases of strong wind or heavy rain. Height of mound was designed to secure more than 1 m by combining A and B layers. Narrow zones, in which mound with stable slope degree cannot be prepared, was designed to equip the standard soil depth with the introduction of stone for supporting. On the other hand, plants with shallow root system were arranged in some zones, in which satisfactory soil depth cannot be ensured. Plants were arranged in the order of tree, sub-tree, and shrub from center to edge on the mound to make a mature forest of a dome shape in the future. Dispersion of plants was designed to be random pattern rather than clumped one. Problems on creation of the environmental forest by such ecological design were found to be management or inspection by non-specialized project operators and inspecting officers, and regulations for construction without ecological background. Alternative plans to solve such problems were suggested.

• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.337-345
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• 2000

The flora and vegetation of salt marsh region in Nonhyun-dong, Incheon were investigated from June 1999 to June 2000. The surveyed region includes the several abandoned salt farms and natural salt marshes developing along the intertidal zone at the stream of the Sorae Inlet, Yellow Sea and is going to be constructed a costal ecopark. In this survey 14 species of halophytes were collected in the region, among them Suaeda maritima is the most common one, Salicornia herbacea, Artemisia scoparnia and Aster tripolium are also observed popularly. The flora of the abandoned salt farms is very similar to that of the natural salt marshes. However, the bank areas between the abandoned salt farms and the natural salt marshes showed more richness of species diversity including 21 naturalized plants. The vegetations on the natural salt marshes are mainly composed of Suaeda maritima -Artemisia scoparnia and Suaeda maritima communities. On the other hand, various plant communities were investigated in the abandoned salt farms such as Suaeda maritima-Salicornia herbacea, Phragmites communis-Typha angustata, Suaeda asparagoides -Suaeda maritima and Phragmites communis communities. Based on the plant physiognomy and species diversity, the region can be divided into three types of area for conservation, that is, the area composed of well-developed vegetation, disturbed one by human activities and plant withering area. Futhermore, according to the construction of the costal ecopark in the region the conservation scheme for each area was discssed.

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.219-230
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• 2013

Species distribution modeling is one of the most effective habitat analysis methods for wildlife conservation. This study was for evaluating the suitability of species distribution to distance between forest patches in Seoul city using tits. We analyzed the distribution of the four species of tits: varied tit (Parus varius), marsh tit (P. palustris), great tit (P. major) and coal tit (P. ater), using the landscape indexes and connectivity indexes, and compared the resulting suitability indexes from 100m to 1,000m. As factors affecting to the distribution of tits, we calculated landscape indices by separating them into intra-patch indices (i.e. logged patch area (PA), area-weighted mean patch shape index (PSI), tree rate (TR)) and inter-patch indices (i.e. patch degree (PD), patch betweenness (PB), difference probability of connectivity (DPC)), to analyze the internal properties of the patches and their connectivity by tits occurrence data using logistic regression modeling. The models were evaluated by AICc (Akaike Information Criteria with a correction for finite sample sizes) and AUC (Area Under Curve of ROC). The results of AICc and AUC showed DPC, PA, PSI, and TR were important factors of the habitat models for great tit and marsh tit at the level of distance 500~800m. In contrast, habitat models for coal tit and varied tit, which are known as forest interior species, reflected PA, PSI, and TR as intra-patch indices rather than connectivity. These mean that coal tit and varied tit are more likely to find a large circular forest patch than a small and long-shaped forest patch, which are higher rate of forest. Therefore, different strategies are required in order to enhance the habitats of the forest birds, tits, in a region that has fragmented forest patches such as Seoul city. It is important to manage forest interior areas for coal tit and varied tit, which are known as forest interior species and to manage not only forest interior areas but also connectivity of the forest patches in the threshold distance for great tit and marsh tit as adapted species to the urban ecosystem for sustainable ecosystem management.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.39-49
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• 2007

We investigated to understand the differences in the karyotypes and the reproductive characteristics between the diploid clam, Corbicula japonica in the brackish water and the triploid clam, C. fluminea in the freshwater. The number of chromosomes of the diploid C. japonica were 38, which can be grouped into 19 pairs of two homologues. These can be divided into 11 pairs of telocentric, 4 pairs of subtelocentric, 3 pairs of submetacentric and one pair of metacentric chromosomes. C. japonica is oviparous and dioecious. The clam has two pairs of gills, with the inner and outer-demibranchs, however, they do not act mainly as marsupia. External fertilization occurs in the brackish water. The triploid marsh clam, C. fluminea has 54 chromosomes, which can be grouped into 18 sets of three homologues. These 18 sets can be divided into one metacentric group, five submetacentric groups and 12 subtelo- or telocentric groups. C. fluminea is ovoviviparous and functional hermaphrodite. The triploid condition may be closely related to hermaphroditism. This species has the inner-demibranchs acting mainly as marsupia. The depletion of ripe eggs occurred in the inner-demibranchs of the gill during the incubatory periods, and ripe eggs produced in the hermaphroditic follicles in the gonad during the non-incubatory periods. The gonad developmental stages of two marsh clams (C. japonica and C. fluminea) can be divided into five stages: early active stage, late active stage, ripe stage, partially spawned stages, and spent/inactive stage.