• Title/Summary/Keyword: morphological variations

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Distribution and Morphology Characteristics of Native Zoysiagrasses (Zoysia spp.) Grown in South Korea (한반도에 자생하는 한국잔디류(Zoysia spp.)의 분포 및 형태적 특성)

  • Bae, Eun-Ji;Park, Nam-Chang;Lee, Kwang-Su;Lee, Sang-Myung;Choi, Joon-Soo;Yang, Geun-Mo
    • Asian Journal of Turfgrass Science
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    • v.24 no.2
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    • pp.97-105
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    • 2010
  • This study focuses on investigating morphological characteristics and variations level in native zoysiagrasses from costal regions and islands in South Korea. In addition, this were collected to conserve germplasm for the breeding of zoysiagrass. One hundred fifty-nine of native zoysiagrasses were collected from 16 different cities and districts. There were morphological evaluations, including plant height, leaf width, leaf length, leaf angle, seed length(SL), seed width(SW), SL/SW ratio and number of seed per spike in native zoysiagrasses. Type of Z. japonica, Z. sinica, Z. macrostachya and Z. matrella showed significant variations in plant height, leaf length, leaf angle and number of seed per spike depending on where they were collected from. On the other hand, little variation were found in leaf width, seed length, seed width and SL/SW ratio. We have discovered a variety of variations among the investigated traits in hybrid zoysiagrass. These results can be used as basic information for development of zoysiagrass breeding.

Species and Hybrid Identification of Genus Coreoleuciscus Species in Hwnag-ji Stream, Nakdong River Basin in Korea (낙동강 상류 황지천에 서식하는 쉬리속(genus Coreoleuciscus) 어류 집단의 종 동정 및 잡종 판별)

  • Song, Ha-Yoon;Kim, Jae-Hun;Seo, In-Young;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.29 no.1
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    • pp.1-12
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    • 2017
  • A natural hybrid of interspecific between the Coreoleuciscus splendidus and C. aeruginos (Cypriniformes: Cyprinidae) was captured in the Hwang-ji Stream, a tributary of the Nakdong River basin in Korea. An interspecific hybrid between C. splendidus and C. aeruginos was genetically identified based on morphological characteristics and the sequence analysis of nuclear recombination activating gene 1 (RAG1) gene (1,334 bp) and mitochondrial cytochrome c oxidase subunit 1 (CO1) gene (1,551 bp). As a result of morphological variations, the natural hybrid appeared to have an intermediate character between two parental species (C. splendidus and C. aeruginos) in three variations of black array (s) on dorsal, caudal and anal fin rays. Phylogenetic analysis inferred from RAG1 and CO1 sequence data revealed that Coreoleuciscus populations from Hwang-ji stream consist of two pure Coreoleuciscus species and a hybrid individual group. The individuals were clearly identified the cross and reciprocal hybrid by CO1 gene analysis. In RAG1 gene, 13 nucleotide variation loci were detected and the hybrid individuals displayed the double peaks of sequence chromatograms at the 9 diagnostic positions. In this study, molecular data and morphological variations were clearly demonstrated that hybridization did occur between C. splendidus and C. aeruginos. However, F2 hybrid generation and reproductive capacity of F1 hybrid individuals were not demonstrated.

DNA Barcoding of a Colonial Ascidian, Botrylloides violaceus (Ascidiacea: Stolidobrachia: Styelidae), from South Korea

  • Lee, Taekjun;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.1
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    • pp.26-30
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    • 2021
  • Botrylloides violaceus is native to the Northwest Pacific, including Korea. This species has many color variations in alive condition and a variety of zooid compound forms, and therefore difficult to identification in the field survey. This is the first report of COI DNA barcodes of B. violaceus from Korea. The intra-specific pairwise distance between Korean and UK populations had ranged from 1.4% to 2.6%. The inter-specific variations between B. violaceus and other Botrylloides species were 21.0-36.8%. The new DNA barcodes for Korean B. violaceus may be helpful in the identification of colonial ascidians, which is a difficult task when based on morphological identification.

New Report of Parabopyrella elongata (Isopoda, Epicaridea, Bopyridae) in Korean Waters, with Notes on Morphological Variations

  • Sung Hoon Kim;Seong Myeong Yoon
    • Animal Systematics, Evolution and Diversity
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    • v.39 no.4
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    • pp.169-175
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    • 2023
  • A branchial parasitic bopyrid, Parabopyrella elongata (Shiino, 1949), is newly recorded in Korean fauna. Parabopyrella elongata differs from its congeners by the following characteristics: the head is smooth anteriorly in females; the pleon of females has distinct and wide lateral indentations on both sides; the pleotelson has a rounded distal end in females; oostegite 1 has a rounded posterolateral point; the pleon of males is single-segmented; and the uropod is absent in males. In this study, the detailed description and illustrations of the species are presented with an emended key to known Parabopyrella species in the Far East. The variations in P. elongata were also discussed. This is the first report of the genus Parabopyrella from South Korea.

The Potential of Sentinel-1 SAR Parameters in Monitoring Rice Paddy Phenological Stages in Gimhae, South Korea

  • Umutoniwase, Nawally;Lee, Seung-Kuk
    • Korean Journal of Remote Sensing
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    • v.37 no.4
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    • pp.789-802
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    • 2021
  • Synthetic Aperture Radar (SAR) at C-band is an ideal remote sensing system for crop monitoring owing to its short wavelength, which interacts with the upper parts of the crop canopy. This study evaluated the potential of dual polarimetric Sentinel-1 at C-band for monitoring rice phenology. Rice phenological variations occur in a short period. Hence, the short revisit time of Sentinel-1 SAR system can facilitate the tracking of short-term temporal morphological variations in rice crop growth. The sensitivity of SAR backscattering coefficients, backscattering ratio, and polarimetric decomposition parameters on rice phenological stages were investigated through a time-series analysis of 33 Sentinel-1 Single Look Complex images collected from 10th April to 25th October 2020 in Gimhae, South Korea. Based on the observed temporal variations in SAR parameters, we could identify and distinguish the phenological stages of the Gimhae rice growth cycle. The backscattering coefficient in VH polarisation and polarimetric decomposition parameters showed high sensitivity to rice growth. However, amongst SAR parameters estimated in this study, the VH backscattering coefficient realistically identifies all phenological stages, and its temporal variation patterns are preserved in both Sentinel-1A (S1A) and Sentinel-1B (S1B). Polarimetric decomposition parameters exhibited some offsets in successive acquisitions from S1A and S1B. Further studies with data collected from various incidence angles are crucial to determine the impact of different incidence angles on polarimetric decomposition parameters in rice paddy fields.

Facial Region Tracking in YCbCr Color Coordinates (YCbCr 컬러 영상 변환을 통한 얼굴 영역 자동 검출)

  • Han, M.H.;Kim, K.S.;Yoon, T.H.;Shin, S.W.;Kim, I.Y.
    • Proceedings of the KIEE Conference
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    • 2005.05a
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    • pp.63-65
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    • 2005
  • In this study, the automatic face tracking algorithm is proposed by using the color and edge information of a color image. To reduce the effects of variations in the illumination conditions, an acquired CCD color image is first transformed into YCbCr color coordinates, and subsequently the morphological image processing operations, and the elliptical geometric measures are applied to extract the refined facial area.

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Effect of Morphological variations on the Biodegradability of linear and star shaped PGCL (선형과 스타형 Poly(glycolide-co-$\varepsilon$ -caprolactone)의 형태학적 미세 구조변화가 분해성에 미치는 영향)

  • 조도광;박준욱;임승순;김수현;김영하
    • Proceedings of the Korean Fiber Society Conference
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    • 2001.10a
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    • pp.179-182
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    • 2001
  • 지방족 폴리에스터는 보통 의료용 고분자 및 환경분해성 고분자로 알려져 왔으며, 이에 따라 지방족 폴리에스터와 그의 공중합물, 그리고 다른 상용고분자와의 블렌드들의 분해 메카니즘에 관한 연구 보고가 이루어져 왔다. 일반적으로 결정성 고분자의 분해성은 일차적인 화학구조외에도 결정의 size나 perfactness, 결정화도 또는 배향도와 같은 미세 구조에 의해서도 크게 영향을 받는다. (중략)

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The Morphological Changes of Deltaic Barrier Islands in the Nakdong River Estuary after the Construction of River Barrage (하구둑 건설 이후 낙동강 하구역 삼각주 연안사주의 지형변화)

  • Kim, Sung-Hwan
    • Journal of the Korean Geographical Society
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    • v.40 no.4 s.109
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    • pp.416-427
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    • 2005
  • This paper aims to investigate morphological changes of deltaic barrier islands in the Nakdong Estuary and especially their spatial variations after barrage construction. We analyzed shorelines, geometrical centroids, and areas to reveal the changes of barrier islands. Here, we suggest three interesting points from this study. First, each individual barrier island in the Nakdong estuary goes through a different stage of the geomorphic cycle. The frontal barrier islands such as Sinja-do and Doyo-deung grow because they are located in front of the gates of the barrage. Sediments in water out of the gates are moved to offshore and then reworked by coastal processes such as waves and tides. Second, on the contrary, Baekhap-deung located behind Doyo-deung now diminishes indicating that sediments mainly move to the frontal growing island. Third, there is no morphological change in several barrier islands far away from the main flow of the Nakdong river such as Jinwoo-do, Daema-deung, and Jangja-do. In conclusion, barrier islands in the Nakdong estuary show distinct spatial variations. As a barrier island is closer to the main channel or is in the frontal location, there happens a very dynamic change in the morphology of the island.

Morphological Variations in Relation to Geographical Distribution of Pond Smelt, Hypomesus olidus Pallas (한국산 빙어의 지리적 형태변이에 대하여)

  • Ryu Bong Suk;LEE Kyung Ro
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.14 no.3
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    • pp.179-188
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    • 1981
  • The authors made an investigation concerning the geographical distribution and some major differentiations in morphological characteristics associated with the each habitat, of the pond smelt, Hypomesus olidus, which was introduced into Korea more than 50 years ago. Major characteristics utilized for the comparison study were upper jaw (maxillary), number of fin rays, scale structure, vertebral count, number of pyloric caeca, number of gill rakers, and the relative measurements of these and other internal characters. 1. The main areas of natural distribution are Paro Lake, Soyang Lake, Han River, Euirim Lake, and Ogjeong Lake (or Unam Lake) and the tributaries of these waters. 2. Morphological variations varied when the mean values of measurements from each area were compared with the standard measurement value by mosaic comparison, and in some instances a significant variation was found. 3. The most significant variations were found in the number of fin rays of pectoral and anal fins; the lengths from the tip of snout to the origin of pectoral fin, from snout to ventral fin, and from snout to anal fin, relative to standard body length; eye depth relative to head length; upper jaw: the number of pyloric caeca and the scale structure. Variations, on the other hand, by each habitat were not clear in the numbers of ventral and dorsal fin rays, gill rakers, vertebrae and lateral line scale : and the depth of caudal peduncle and distance from the tip of snout to the origin of dorsal fin relative to standard body length. 4. The scales of pond smelt showed some differences in the shape of scales, the shape and position of the focus and the number of ridges according to the scale positions on the body. No radii were present. The relations between longitudinal and transverse diameters of the scale suggest that the pond smelts of Soyang Lake and Un-am Lake are closely related, and those of Han River and Euirim Lake are also closely related. 5. The geographical variations in morphology of the pond smelt seem to have resulted from the variations in turbidity, water temperature, salinity (rather conductivity) and currents. 6. From the results obtained, it may be concluded that such factors as supramaxillary, relation between scale length and its breadth, number of caudal vertebrae and eye depth relative to head length may be used as the key characters for the classification of geographical varieties of Pond smelt.

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