• Journal of Ecology and Environment
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• v.31 no.4
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• pp.255-260
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• 2008

A commonly held view in studies of character displacement is that character states of both species are shifted in areas of sympatry. This view has been confirmed in an overwhelming number of cases for ecological character displacement. Excluding species pairs in which one of the two interacting species is found only within the distribution of the other species and species displaying gynogenesis, the pattern of reproductive character displacement is asymmetrical in that the shift in character states between areas of symaptry and allopatry occurs in only one of the two interacting species. Hypotheses for the reasons behind this asymmetry in reproductive character displacement include (1) homogenization by gene flow, (2) other mechanisms of reproductive isolation, and (3) sufficient reproductive isolation being provided by one of the interacting species exhibiting a pattern of reproductive character displacement. Because reproductive isolation can be achieved by divergence at any point in a sequence of premating reproductive behaviors and postmating developments, it is necessary to understand the mechanisms of reproductive isolation of two interacting taxa in areas of sympatry and allopatry and to analyze the relative contributions of potential factors to reproductive isolation to disentangle hypotheses for the patterns of asymmetry.

• Journal of Korean Society of Rural Planning
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• v.15 no.2
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• pp.19-26
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• 2009

The purpose of this study is to build Island biogeography in the basic concept of landscape ecology in South Korea by draw relationship between the species side of quantitative habitats and forest area surveyed in the national database based on investigation of the 2nd natural environment. In addition, try to present criterion of habitats character category after understanding habitats character of emergence area side of quality habitats based on the type of formatting. Species and forest area relationship analyzed using correlation analysis and simple regression analysis. Also habitat character limited composition ratio of neighboring land cover and analyzed using hierarchical cluster analysis to classify type of habitat. As a result, we found that forest area is correlated with number of species, forests which is bigger than 100ha are more important of increase in species' population. And according to land cover composition ratio, bird's classified types of forest inner species, forest edge species, forest outer species and mammal's classified types of forest inner species, forest general species, forest edge species. We suggest that study of species-forest area relationship and emergence habitat character be used as some management plans of species' conservation, protection and restoration.

• Korean Journal of Plant Taxonomy
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• v.34 no.2
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• pp.153-166
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• 2004

Genus Taraxacum propagated through diploid sexual reproduction and polyploid agamospermy. The cluster analysis of Korean(2 species, 4 population), Japanese (2 species 4 taxa 6 population) and Taiwanese (1 species, 3 population) Taraxacum species using 15 measured capitulum morphological characters was conducted to study the speciation of diploid Taraxacum in East Asia. We measured 15 capitulum morphological characters including length of capitulum, length and shape of outer-involucre, corniculate appandage. Within one population, these characters were very various and were overlapped. The result of cluster analysis using morphological character showed that all species were clustered into four groups (Korean species & T. japonicum group, T. platycarpum subspecies group, T. platycarpum subsp. hodense group, T. formosanum group). Korean species, T. hallaisanense (diploid) and T. ohiwanum (diploid, triploid) were clustered into T. japonicum that was occurred in Kansai provinces of Japan. Therefore, we could infer that Korean species was closely related to Japanese T. japonicum of Japanese species.

• ALGAE
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• v.23 no.3
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• pp.187-199
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• 2008

A study on the fine structure of the marine diatom Thalassiosira has been carried out during the periods from January 2007 to March 2008 in Korean coastal waters. As the third series of the Thalassiosira species, a fine structure, description, distribution and taxonomic remarks of the six Thalassiosira species were observed by means of light microscope and scanning electron microscope. The critical features of Thalassiosira species were a shape of external tubes of marginal strutted processes and labiate process. Six species showed each different shape of external tubes, marginal strutted processes and labiate process. The shape of external tube was divided into five types: T shape of Thalassiosira curviseriata, small-rounded shape of T. lundiana, double-layer form and flame shape of T. nordenskioeldii, tulip shape of T. punctigera and tooth-shape of T. tenera. This external character may be able to key character for positive identification of the Thalassiosira species. Of these Thalassiosira lundiana, T. minuscula and T. tenera were new records for Korean coastal waters.

• Current Research on Agriculture and Life Sciences
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• v.27
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• pp.69-75
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• 2009

This research regard it as most meaningful to realize the importance of the hedgerow in cultivated areas functioning as a residual landscape element in rural landscape and set improvement guidelines through landscape character and value analysis to cope with landscape malfunction. The results of summary are as follows. 1) First of all, as a result of landscape character analysis of edge stripe in cultivated land in total of 7 case areas, for example, the edge stripe in cultivated land in case area 4 and 8 maintain the width of 10m and are assessed satisfactory in terms of vegetation development condition, appearance of living species, connectivity, buffer capacity and so on. Also, as a result of structural character of correlation analysis among items, the correlation coefficient between width and appearance of living species showed 0.941, the highest. Following are connectivity and appearance of living species and width and buffer capacity respectively: 0.841 and 0.740. 2) As a result of landscape character analysis of uncultivated stripe in total of 6 case areas, it is analyzed that case area 4 maintains the widest width as almost 4.5m average width and considered valuable as I degree in vegetation development condition, filtering, and connectivity. 3) As a result of problem analysis of uncultivated stripe, for example, case 3, 9, and 10 was analyzed that the width was below 1.25m which is too small to carry out the function of buffer and habitat for living creature, so minimum standard width was set between 4~5m through comprehensive analysis of character of each case area. Based on the result above landscape character, value and problem analysis, main improvement guidelines are set in terms of width, connectivity, filtering, and vegetation development, restrictive practices and so on.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.173-180
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• 2003

To clarify whether the closely related species living in the same area is a population or populations ecologically, leaf morphology, specific leaf area, and fruit and seed production were studied in the natural group of sect. Pes-gallinaceua of Corydalis of Namhansansung area from 1999 to 2000. There were 352 plants in one square meter and total eight species or varieties were identified. Of the 352 plants, the number of C. turtschaninovii was the most with 103(29.3%), and that of C. ambigua was the next with 78(22.2%), and that of C. turtschaninovii var. fumariaefolia was the smallest with 9(2.6%). In the 28 plants having spotted leaves, central leaflet did not parted or again parted. The extent of partition with the plant was various from non-parted type to perfectly two-parted type (three leaflet). Between two extreme types, there were diverse types so that this character formed a gradient. The rate of length/breadth was in the range of 0.79~2.17. This character was related to the extent of leaflet partition but did not well expressed the distinguishing trait along a species. The number and the type of serration were diverse and there was no sharp borderline among the species or varieties. Ecological properties, specific leaf area, the number of fruit per plant, and the number of seed per fruit, varied with a wide range in a species or variety but differences between species or variety were not significant. Therefore, the Corydalis group studied was regarded as a population on the three criteria: (1) possibility of interbreeding, (2) continuity of leaf morphology, (3) irrelevance between character and species, (4) similarity of several ecological properties.

• Journal of Plant Biology
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• v.39 no.2
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• pp.149-159
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• 1996

The order of Rhododendro-Quercetalia mongolicae representing temperate oak forests in Korea was characterized in terms of presence of taxa of different rank. 140 releves were analysed for percentage contribution of each species, genera and families in syntaxa under consideration as well as extracton of diagnostic genera and families for syntaxa by an ordination technique. The Rhododendro-Quercetalia is characterized by high diversity of tree and shrub species contributing 40% of the total floristic composition as well as by a high contribution of the genus Rhododendron and the absence of the genus Fagus, characteristic of the QuercoFagetea sensu lato. The character families for the Rhododendron and Quercus include Liliaceae and Compositae, whereas Acer, Carex, Viola, Rhododendron and Quercus are the most common among genera. Rhododendron and Quercus are regarded as the transgressive cheractergenera, whereas the families of Pinaceae and Ericaceae are considered companions (in sense of the terminology of the Braun-Blanquet syntaxonomy) for the order. Family appeared to be an inadequate rank for diagnoses of alliances and suballiances. On the other hand, genus was found to be the most effective rank in differentiating the alliances and suballiances. The Lindero-Quercenion shares the same character-genera with the order Rhododendro-Quercetalia. Character genera of the suballiances Callicarpo-quercenion are Carpinus, Styrax, Smilax and Callicarpa, and those of the Pino-Quercion list Euonymus, Saussurea and Tilia.

• ALGAE
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• v.20 no.4
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• pp.325-331
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• 2005

Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.

• Journal of Species Research
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• v.5 no.1
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• pp.49-156
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• 2016

Fourteen new species and A. coreana Morimoto, 1970 of Allobathynella Morimoto and Miura, 1957 are (re-)described and illustrated from the Korean Penninsula. Comparison of the external morphology of these species and two previously known species, A. japonica Morimoto and Miura, 1957 and A. shinjongieei Park and Cho, 2008 enables us to amend the generic diagnosis. A 7-segmented antennule turns out to be inconsistent character due to A. wonjuensis sp. nov., which has a 6-segmented antennule. On the other hand, the exopodal distal segment of thoracopods I-VII with a tiny terminal knob and with outer seta covered by long and strong barbs is proved to be a autapomorphic character of the genus. The 14 new species belong to the mirabilis-group and display more or less similar morphology. However, they differ from A. coreana, A. japonica and A. shinjongieei and from each other not only in quantitative but also in qualitative characters. These differences are summarized in tables. The species inhabit hyporheic zones of rivers and each appears to be highly endemic to a given tributary, having a range limit less than 100 km.

• Animal Systematics, Evolution and Diversity
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• v.2 no.1
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• pp.63-78
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• 1986

Two species of Moroco oxycephalus and M. lagowskii were studied to examine patterns of genic variation and morphological difference within and between populations of two species, and to clarify their taxonomic status and geographic distribution. The number of scales above lateral line(SAL) was the key character to classify these species. On the average, M.lagowskii had 22 or more SAL whereas M.oxycephalus had 20 or less. Previously known character of the position of dorsal fin was found to be not appropriate to distinguish them. Five loci, Gp, st-1, Est-2, Est-3 and Got-1 , showed fixed difference electrophoretically between two species and these could be used as genetic markers to identify them. The degree of genic variation of M. oxycephalus was four fold higher(H=0.032) than that of M. lagowskii(H=0.008) but both species were far less than the average genic variation of freshwater fish in general. Rogers' genetic similarity coefficients between two species were S=0.692 and their presumed divergent time was estimated to be sbout 1.8million years ageo. Detailed survey of the geographic distribution of thses revealed that M.lagowskii was distributed in northeastern part of South Korea(Ganseong , Gangreung, Wangsan, and Oggye) and M. oxycephalus was occupied rest of the peninsula. The distrance between Oggye, the southern limit of M. lagowskii distribution , and Samwha (near Samcheog), the northern limit of M.oxycephalus, was aobut 15 Km apart and no symparty was found in between.