• Journal of the Korean Geographical Society
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• v.40 no.4 s.109
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• pp.428-440
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• 2005

There is currently no agreement among archaeologists, environmental historians, and paleoecologists as to the relative significance of pre- and post-Conquest human impact on the environments of Highland Mexico. This paper presents the results of pollen, microscopic charcoal, dung fungal spore, isotope, and magnetic susceptibility analyses on ca. 4m sediment core. The coring site is Hoya Rincon de Parangueo, one of the seven maar lakes in the Valle do Santiago. Amaranthaceae pollen, one of important disturbance indicators and Zea mays pollen obviously indicate two periods of agricultural activities. The first period begins ca. 400 B.C. and ends ca. A.D. 850. The second begins around A.D. 1550 and continues to the present. During the first period, the degree of agricultural activities was related to periodical sunspot cycles and the most intense activities were present between ca. A.D. 150-ca. A.D. 400. The abrupt increase of $\delta^{18}O$ around 280cm may reflect that an important transition to a dry phase took place around A.D. 450. People probably stopped cultivating crops due to dry conditions prevailing since ca. A.D. 450. The second period, the post-Conquest, exhibits a dramatic increase of sporormiella, dung fungal spores resulted fron the introduction of cattle. Low Poaceae frequency and charcoal production and high $\delta^{13}C$ values, magnetic susceptibility, and organic contents all indicate the arrival of the Spanish. Most importantly, it seems that mesquite (Prosopis juliflora) could have benefits from declined fire frequencies caused by cattle grazing. The study area is now entirely dominated by woody plants like mesquite, which clearly demonstrates that serious vegetation change occurred in the study area.

• Analytical Science and Technology
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• v.16 no.5
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• pp.418-425
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• 2003

Inorganic elemental content of bottom ash generated from municipal solid waste incinerator was determined by neutron activation analysis. Bottom ash samples were collected monthly from incinerator located in city D, strained out by the 5 mm sieve, dried by oven and pulverized by agate mortar. The samples were irradiated at NAA #1 irradiation hole in HANARO research reactor of Korea Atomic Energy Research Institute and the irradiated samples were measured by HPGe-gamma-ray spectrometer. From the activity of measured nuclides, 33 elements including As, Cr, Cu, Fe, Mn, Sb and Zn were determined applying activity creation formula and nuclear data. The quality control was conducted by simultaneous analysis with NIST standard reference materials.

• Nuclear Engineering and Technology
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• v.24 no.2
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• pp.163-167
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• 1992

Nondestructive neutron activation analysis of copper in high purity Aluminum samples which can be used as a parameter of impurity is investigated and determined. Other 23 trace impurity elements in the samples are also determined. In the analysis of copper, the new irradiation method using thermal column was applied to reduce the interfering activity of 24Na produced by 27Al(n,$\alpha$)24Na reaction induced by fast neutron. As a result, the interference can be reduced to 100 times more than other activation methods. Also the influence by activity of 24Na is found in the range of 2~3 %. It has been observed that the copper contents in so-ratted“six nine”class standard aluminum samples are about 0.54 $\pm$ 0.08 ppm. By the comparison with other values re-ported, our results are reasonable and can be available as a improved routine analysis.

• Journal of the Mineralogical Society of Korea
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• v.26 no.2
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• pp.65-80
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• 2013

Sediment transport mechanism and distribution of organic sediments are elucidated by the study of particle size, mineralogy, organic matters and microfossils of the surface samples collected from seafloor adjacent Dokdo island. Shallow marine sediments are dominated by coarse- grained sediments including gravel and sand, and their sedimentation has mainly been controlled by traction. While the samples collected from oceanic zone are characterized by high contents of fine- grained sediments such as silt and mud in bulk sediments, and the changes of mineral compositions including clay minerals and feldspar, and the fine sediments have been deposited mainly by suspension. The change of organic sedimentary communities is detected between neritic and oceanic zone. Although marine organic matter is predominant in neritic zone, terrestrial organic matter is monopolized according to increasing water depth. This trend is associated with grain size of sediments. The results also suggest that high pollen concentrations in whole organic matters may played an important role in excessive organic carbon in sediment.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.87-87
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• 2019

현대인의 생활수준의 향상에 따른 관상식물의 관심이 증가하여, 자생초화류를 활용하기 위한 연구가 진행되고 있다. 산꼬리풀[Veronica rotunda var. subintegra (Nakai) T.Yamaz.]은 국내 특산식물로서 산지의 초원에서 자생하고, 쪽빛을 내는 화기는 청아한 느낌을 주어 관화식물로서 이용가능성이 높다. 본 연구는 산꼬리풀의 분화 재배기술을 확립하고자 2018년 7월 2일부터 10월 15일까지 수행하였다. 대조구는 플라스틱 화분 10호에 원예상토를 충진한 다음 200구에 셀당 4립 파종하여 생산된 유묘를 정식하였다. 실험은 식재용기(플라스틱 8, 10, 12호 화분, 비닐포트 3, 4치), 토양종류[원예상토 단용, 중화 피트모스:펄라이트(3:1, 4:1), 마사토:중화 피트모스(2:1, 3:1)], 묘의 소질[파종립수(1, 2, 4, 6립), 파종용기(162, 200, 288구 트레이)] 등이 생육에 미치는 영향을 분석하였다. 연구의 결과, 식재용기에 따른 생육은 플라스틱 화분 12호에서 왕성하였고, 포트의 용적량이 클수록 경직경, 측지수, 마디수, 엽수, 개화율이 유의적으로 증가하였다. 토양종류에 따른 생육은 원예상토에서 가장 왕성하였고, 측지수, 경직경, 마디수, 엽수 및 개화율이 모두 우수하여 관상용 재배에 적합하였다. 피트모스 혼용토는 생육이 억제되는 동시에 잎이 황화되는 현상이 나타났다. 마사토 혼용토의 경우, 생육이 억제되는 결과를 보였다. 셀당 파종량을 달리한 유묘를 정식하여 재배한 결과, 초장, 절간장은 파종량이 증가할수록 감소하였고, 포트당 마디수와 엽수는 증가하였으나, 1립 파종묘를 제외하고 유의적인 차이는 없었다. 개화율은 4립 파종묘(44.4%)가 1, 2, 6립 파종묘(20.8~25.0%)보다 높았다. 육묘용기별 생육은 초기생육이 우수하였던 162구 생산묘가 정식 후 재배에도 왕성한 생육을 나타내었다. 결론적으로, 산꼬리풀의 최적의 분화재배를 위해 플라스틱 화분 12호에 원예상토를 충진한 다음 162구 트레이에 포트당 엽수와 개화율이 높은 4립 파종하여 생산된 유묘를 정식하여 재배하는 것이 우수할 것으로 판단된다. 경제적 측면을 고려하여 토양은 비교적 생육이 양호하였던 마사토의 활용방안을 검토하는 것이 좋을 것으로 생각된다.

• The Korean Journal of Ecology
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• v.10 no.4
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• pp.195-204
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• 1987

Pollen analysis of moor peat of Daeam Mountain revealed vegetational history around Daeam Mountain. The pollen stratigraphy might be zoned into three, Zone I, Zone II and Zone III for the past 2, 200 years. The time required for amount of the accumulated peat in the moor was estimated in terms of the balance of the accumulation and decay of organic carbon of the deposit peat. Zone I(770~2, 200 yr BP) had Pinus and Quercus as main elements. Gramineae decreased while Typhaceae, Cyperaceae and spores such as Polypodiaceae increased. Zone II(300~770 yr BP) showed warming trend which is suggested by high pollen concentrations of Quercus, Juglans, Carpinus, Ulmus and by a more diverse flora of deciduous borad-leaved trees than Zone I. Pinus decreased in this zone. It suggests that the overall environment became milder than Zones I and III. Zone III(earlier than 300 yt BP) was predominantly Quercu and Pinus with amount of nonarboreal species such as Artemisia, Gramineae and Chenopodiaceae, that was grown under dry conditions. It suggests that overall environment vecome humid by comparison with the present time and it is surmised the course of boggy ground formation by a retrogressive succession.

• Journal of The Geomorphological Association of Korea
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• v.24 no.4
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• pp.1-12
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• 2017

This study tried to reconstruct paleovegetation environments during the late Holocene with pollen analysis from archeological trenches at the right bank of Geumgang in Sejong-si. The lower hills was dominantly covered with pine trees, while alder trees and hygrophytes extended on the floodplain since 2,000yr BP. The pollen composition of Alnus dominance in the floodplain during the times is different from the general charateristics of Korean peninsula. Such a phenomenon is thought to be influenced by the fluvial process on the floodplain in the middle reaches of Geumgang around Sejong-si. Mihocheon and some tributaries join to Geumgang around Sejong-si, and the channel of Geumgang becomes narrow around the boundary between Sejong-si and Gongju-si. This narrow channel could attribute to the formation of extensive floodplain around Sejong-si. Moreover, human impacts such as agriculture appear continuously since 1,800yr BP.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.219-226
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• 2000

Lycopersicon peruvianum has a gametophytic self-incompatibility (GSI) mechanism controlled by a single genetic locus (S locus) with multiple alleles. S RNases, an allelic series of abundant stylar proteins, are products of the S locus in L. peruvianum and other Solanaceous plants. The $S_{11}$ RNase gene from L. peruvianum was introduced into a self-compatible (SC) species (Lycopersicon esculentum) to examine whether the expression pattern in the heterologous host mimics that in L. peruvianum. The resultant transgenic L. esculentum plants expressed the introduced gene highly in their styles, which is similar manner to the expresion in L. peruvianum. The $S_{11}$ RNase gene was expressed in the syle at a similar stage of flower development in both transgenic plants of L. esculentum and L. peruvianum without any morphological changes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.47-58
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• 2023

The quality and yield of crops produced using field cultivation are expected to decrease due to the recent global climate change caused by extreme weather. The plant reproductive stage associated with crop yields is a highly vulnerable period to global warming caused by high temperatures. This study analyzed the adzuki bean's yield properties, antioxidant contents, and pollen viability of adzuki bean (Vigna angularis L.) under high-temperature stress and growth periods in a temperature gradient greenhouse that forms 0 to 4℃ above the outside temperatures. As the main variety of red beans cultivated in Korean farms, the "Arari" red bean was grown in the rain shield greenhouse and the temperature gradient greenhouse from 2021 to 2022 in Milyang, Korea. Compared to 2022, it showed a 0 - 1.0℃ lower temperature during the whole growth period in 2021. However, its average temperatures were 0 - 3.7℃ higher in the vegetative stage and 0.4 - 2.4℃ higher in the anthesis stage in 2021. The lowest yield (6.8 ± 0.7 g) was at the highest temperature (T4: low, 23.6℃; average, 28.5℃; high, 35.8℃) during the anthesis stage in 2021. The temperatures of the mature stage were 1.7 - 3.9℃, which were higher in 2022 than in 2021, although the low temperatures of 2022 were lower than in 2021. The yields of the mature stage in 2022 increased more than in 2021 because of the high temperature of the mature stage. The growth and yield were good at 40.5℃ in the vegetative stage. However, growth was poor when the average temperature was 27.0℃ or higher, and yields decreased during the flowering period. Total polyphenol and flavonoid contents were increased, and the pollen viability was 40.75% in the whole growth period at high temperature (T4: low, 22.9℃; average, 28.8℃; high, 36.9℃). These results showed that the antioxidant levels increased when the antioxidant component was affected at higher temperatures than at normal. In contrast, the pollen viability-related yield decreased as the temperature increased. Our results are the basic data for field growers and the breeding of thermos-tolerance in adzuki beans to prepare for the changeable future climate.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.31-48
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• 1998

In this paper, pollen types of plants and Pb, N, P, K, Ca and Na in pallens of trees were investigated to control the air and soil pollutions. Morphological types of about 500 species of plants were identified to make the best use of paleontology, medicine and pharmacy. There were the positive correlations between Pb, N, P, K,Ca and Na contents in pollens and soils, respectively. A heavy metal, Pb, contained in pollens was not absorbed by rats. This fact should be utilized to purify air and soils polluted by Pb. Key words: Pb, Pollen, Pollution, puripication, Control.