• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.62-65
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• 2010

This study was carried out to estimate the size and exine pattern of pollen grains in seven species of the genus Lilium by using scanning electron microscope. Exine of pollen grains, which were all monad, took the prolate forms with a pollen aperture. However, there were various L/W ratio between length (L) and width (W) of pollen grains among selected Lilium species. The pollen of L. distichum was oblong shape which had the highest L/W ratio of 2.59. On the other hand, that of L. concolor var. partheneion was broadly elliptical shape close to circle which had the lowest L/W ratio of 1.82. The surface patterns of exine were reticulate in all Lilium species that have showed diverse forms in their lumina. Pollen length and width in L. lancifolium had the greatest value, 115.90 and $46.54{\mu}m$, respectively, in comparison with those of L. tsingtauense, 70.33 and $38.72{\mu}m$, respectively. Except L. distichum and L. leichtlinii var. maximowiczii which had a similar pollen length within standard errors, the others in Lilium species showed different sizes, respectively. Therefore, these results indicated that pollen length could be a better standard for the classification of Lilium species than exine surface patterns or pollen dissection area.

• Proceedings of the KGS Conference
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• 2003.11a
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• pp.34-39
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• 2003

밀양강 중류부 충적평야의 화분분석 결과를 통하여 홀로세 후기 동안의 식생환경을 복원하고 한반도 남부지방의 농경의 기원과 확산에 대해 검토하였다. 경상남도 밀양시 산외면 금천리 단장천 충적평야에서 화분분석을 행하였다. 고고학 유적발굴을 위해 절개한 트랜치 T6(14.75-15.90m a.s.l. : 두께 1.15m)과 T9(17.00-15.60m a.s.l. : 두께 1.4m)의 노두 단면 중에서 비교적 유기질이 풍부한 실트층 및 토탄층에서 5cm등간격으로 채취하여 목본화분(AP: Arboreal Pollen)이 200개 이상이 될 때까지 검경하였다. (중략)

• The Korean Journal of Quaternary Research
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• v.24 no.1
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• pp.25-33
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• 2010

Holocene vegetation and climate changes were assumed on the basis of pollen records from Wonpyeong Trench II-3 of the Osong archaeological site, Cheongju, Chungbuk Province, Korea. An organic matter beared in coarse sediments appeared to be low throughout the succession. Although an occurrence of pollen grains is not high, some dominant and principal taxa may indicate vegetation changes response to climate changes in central inland area of the Korean Peninsula. The age determination can be estimated with indirect way by comparing with previous age-controlled pollen studies. It is assumed that the former last glacial conifer forests had been changed into open mixed conifers and deciduous broadleaved forest during the early Holocene period. Warmer and more humid climate conditions, during the mid-Holocene, might have allowed the hardwoods including deciduous- and evergreen-broadleaved trees, and warm-preferring pine tree to flourish. Subsequently, the former forests were replaced by mixed of conifer and deciduous broadleaved forest owing to deterioration of climate conditions during the late Holocene. Human activity is also detected by agricultural indicators, such as buckwheat and large pollen grains comparable to corn, in upper most pollen profile. During this time, the forests in studied area were primarily affected by human disturbance rather than natural environment.

• Journal of the Korean Geographical Society
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• v.34 no.4
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• pp.371-384
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• 1999

디퓨젼 공식 모형은 한국 하천의 중.상류 지역의 하안 단구의 단구애와 같은 삭박 사면에 대한 연대 측정에 유용하게 적용될 수 있다. 지형 연대 측정 방법은 최대 사면각, 사면의 높이 등과 같은 사면단면에 대한 측정된 자료를 사용하는 보조적 연대 측정법의 하나이다. 토탄층에 대한 탄소연대측정법 또는 화분분석과 같은 방법으로 잘 통제되어진 연대를 이 모형에 적용하여 생성 연대를 모르는 다른 사면의 연대를 추정하는데 사용될수 있다. 적용사례로 경북 영양의 연지 저위단구에서 구해진 연대값 6ka를 이용하여, 최대 사면각과 사면의 높이간의 모의실험을 통해 연지 단구의 저위면/중위면 사이의 단구애 상의 삭박률 100 10-4m2/yr.을 구할수 있었다. 이 삭박률을 영춘 단구의 저위면/중위면 사이의 단구애의최대 사면각과 사면 연대간의 모의실험에 적용하여 영춘 단구의 저위면/중위면 사이의 단구애의 형성 시기를 약 37,000년 전으로 구할 수 있었다. 그러나 보다 정밀한 값을 얻기 위해서는 남한강 중.상류의 단구 지역에 대한 적절한 사면 측정 자료가 요구된다.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.7-31
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• 2000

Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

• Nuclear Engineering and Technology
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• v.5 no.2
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• pp.137-149
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• 1973

A method of activation analysis, based on the irradiation and counting of an iron wire which contains manganese impurity as the single comparator. has been elaborated by critical evaluation of nuclear data involved in activation and activity measurement. The variation of effective cross section is investigated as a function of the spectral index and other parameters such as a measure of the proportion of epithermal neutrons in the reactor spectrum. The errors induced by shifts in the neutron spectrum in the irradiation positions are discussed. The known amount of each element is irradiated simultaneously together with the single comparator, and the obtained values are compared with the known amount of each element. The results show that en general the random errors are not greater than those obtained by using the conventional relative method, but the systematic errors were up to about 20%. This method is applied to the determinations of fourteen rare earth elements in monazite as well as other seven elements in the standard kale powder. The satisfactory reproducibility of the present method makes possible the determination of the elements with an accuracy attainable with the conventional relative method.

• Korean Journal of Plant Taxonomy
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• v.42 no.2
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• pp.141-149
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• 2012

To clarify some ambiguous diagnostic characters of Callicarpa japonica Thunb. and Callicarpa dichotoma (Lour.) K. Koch in Korea (Verbenaceae), the external morphology and micromorphology (leaf, anther, pollen, fruit, in particular endocarp surface and structure) of two taxa are studied and described in detail. It is confirmed that the following characteristics (e.g., the stem outline in a cross-section, the bud shape and length, the corolla tube length and the lobe length, the pattern of the anther dehiscence and length, and the endocarp morphology) are useful for distinguishing these two taxa. In particular, following three characteristics are most useful for an identification: (1) the corolla tube length of C. japonica (2.5-4.6 mm) is longer than that of C. dichotoma (0.7-1.0 mm); (2) the anther is dehiscing by an apical pore at the anthesis of C. japonica, while it is opening by a long fissure from the apex to the base in C. dichotoma; and (3) the edge of the endocarp (lateral view) in C. japonica is concave, while in C. dichotoma it is shown to be flat. On the other hand, the teeth state on the leaf margin and the position of inflorescence are not good diagnostic characteristics for identification. Additionally, the keys for all known Callicarpa taxa in Korea are provided.