• Title/Summary/Keyword: Ecological evolution

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A Study on the Soil Respiration in a Quercus acutissima Forest (상수리나무림의 토양호흡에 관한 연구)

  • Lee, Yun-Yeong;Mun, Hyeong-Tae
    • The Korean Journal of Ecology
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    • v.24 no.3
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    • pp.141-147
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    • 2001
  • Soil respiration and some environmental factors which affect soil respiration were studied in an oak forest, Kongju, Korea. Soil respiration was measured at midday of the 15th and 30th day at every month in control(Con), artificial forest gap (Gap) and litter removed area (Lr) with portable CO₂ Analyzer equipped soil respiration chamber. In July, maximum soil respiration in Con, Cap and Lr was 15.6, 11.2 and 7.7 CO₂μmol·m/sup -2/·s/sup -1/, respectively. Respiration in Gap and Lr decreased by 28.6% and 50.6%, respectively, compared with that in Con. Annual amount of soil CO₂ evolution from Con, Gap and Lr was 6.86, 5.84, 3.81 kg·m/sup -2/·yr/sup -1/, respectively. Annual amount of CO₂ evolution in Gap and Lr decreased by 14.8% and 44.5%, respectively, compared with that in Con. Soil respiration rates exponentially increased with temperature. Temperature of soil surface and at 5 cm depth was strongly related to soil respiration rates in Con (r₂=0.87, 0.93), Gap (r₂=0.81, 0.88) and Lr (r/sub 2/=0.89).

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Origin and evolution of Korean ginseng revealed by genome sequence

  • Cho, Woohyeon;Shim, Hyeonah;Yang, Tae-Jin
    • Journal of Ginseng Culture
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    • v.3
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    • pp.1-10
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    • 2021
  • Panax ginseng (Ginseng or Korean ginseng) is one of the most important medicinal herbs in the world. We made a high-quality whole genome sequence of P. ginseng using 'Chunpoong' cultivar, which is the first cultivar registered in Korea Seed and Variety Service (KSVS) with relatively similar genotypes and superior phenotypes, representing approximately 3 Gbp and 60,000 genes. Genome sequence analyses of P. ginseng and related speciesrevealed the origin of Korean ginseng and the ecological adaptation of 18 Panax species around the world. Korean ginseng and American ginseng (P. quinquefolius) are tetraploid species having 24 chromosome pairs, while the other 16 species are diploid species with 12 chromosome pairs. Panax and Aralia are the closest genera belonging to the Araliaceae family that diverged approximately 8 million years ago (MYA). All Panax species evolved as shade plants adapting to cool climates and low light conditions under the canopy of deep forests from Southeast Asia such as Vietnam to Northeast Asia such as Russia approximately 6 MYA. However, through recurrent ice ages and global warming, most diploid Panax species disappeared due to the freezing winter, while tetraploid P. ginseng may have appeared by allotetraploidization, which contributed to the adaptation to cold temperaturesin Northeast Asian countries including the Korea peninsula approximately 2 MYA. American ginseng evolved by the adaptation of P. ginseng in Northeast America after the intercontinental migration 1 MYA. Meanwhile, most of diploid Panax species survived in high-altitude mountains over 1,600 meters in Southeast Asia because they could not endure the hot temperature and freezing cold. The genome sequence provides good basisto unveil the origin and evolution of ginseng and also supports practical gene chips which is useful for breeding and the ginseng industry.

A Geomorphological Classification System to Chatacterize Ecological Processes over the Landscape (생태환경 특성 파악을 위한 지형분류기법의 개발)

  • Park Soo-Jin
    • Journal of the Korean Geographical Society
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    • v.39 no.4
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    • pp.495-513
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    • 2004
  • The shape of land surface work as a cradle for various environmental processes and human activities. As spatially distributed process modelings become increasing important in current research communities, a classification system that delineates land surface into characteristic geomorphological units is a pre-requisite for sustainable land use planning and management. Existing classification systems are either morphometric or generic, which have limitations to characterize continuous ecological processes over the landscape. A new classification system was developed to delineate the land surface into different geomorphological units from Digital Elevation Models(DEMs). This model assumes that there are pedo-geomorphological units in which distinct sets of hydrological, pedological, and consequent ecological processes occur. The classification system first divides the whole landsurface into eight soil-landscape units. Possible energy and material nows over the land surface were interpreted using a continuity equation of mass flow along the hillslope, and subsequently implemented in terrain analysis procedures. The developed models were tested at a 12$\textrm{km}^2$ area in Yangpyeong-gun, Kyeongi-do, Korea. The method proposed effectively delineates land surface into distinct pedo-geomorphological units, which identify the geomorphological characteristics over a large area at a low cost. The delineated landscape units mal provide a basic information for natural resource survey and environmental modeling practices.

The Evolutionary Medicine of Birth Decision: Psycho-Socio-Ecological Explanations (출산 의사 결정의 진화의학: 정신-사회-생태적 설명)

  • Jihyun, Ryou;Jain, Gu;Hanson, Park
    • Korean Journal of Psychosomatic Medicine
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    • v.30 no.2
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    • pp.99-111
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    • 2022
  • Akey factor in evolution is reproduction, which is also a major concern in medicine. Evolutionists have proposed many theories and hypotheses to explain the low fertility rates of modern industrial societies, which are contrary to maximization of biological fitness. Given that childbirth is the most significant factor affecting reproductive fitness, it is likely that a variety of psychological modules related to childbirth behavior and intention evolved over time. Several evolutionary psychological modules have been proposed in relation to reproduction, including sexual desire, status-seeking, a need for nurturing, and the desire for children. Previously adaptive psychological modules may now be expressed maladaptively due to the discrepancy between the Environment of Evolutionary Adaptedness (EEA) and the environment of modern industrial society. Several evolutionary ecological factors influence childbirth intention in modern society, including individual personality factors, childhood life history experiences, and socioecological factors throughout reproductive life. By focusing on mental, social, and ecological factors, this review examines several hypothetical models relating to evolutionary psychological factors and childbirth decisions in modern industrial society, as well as a possible explanation for the low birth rate.

Five Alexandrium species lacking mixotrophic ability

  • Lim, An Suk;Jeong, Hae Jin;Ok, Jin Hee
    • ALGAE
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    • v.34 no.4
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    • pp.289-301
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    • 2019
  • Mixotrophy in marine organisms is an important aspect of ecology and evolution. The discovery of mixotrophic abilities in phototrophic dinoflagellates alters our understanding of the dynamics of red tides. In the phototrophic dinoflagellate genus Alexandrium, some species are mixotrophic, but others are exclusively autotrophic. There are differences in the ecological roles of autotrophic and mixotrophic Alexandrium in marine food webs. However, of the 34 known Alexandrium species, the mixotrophic ability of >20 species has yet to be explored. In this study, the mixotrophic capabilities of Alexandrium insuetum CCMP2082, Alexandrium mediterraneum CCMP3433, Alexandrium pacificum CCMP3434, Alexandrium tamutum ATSH1609, and Alexandrium margalefii CAWD10 were investigated by providing each species with 22 diverse prey items including bacterium-sized microbeads (1 ㎛), the cyanobacterium Synechococcus sp., algal prey species, and the ciliate Mesodinium rubrum. None of the 5 Alexandrium species fed on any of the prey items. These results increase the number of Alexandrium species lacking mixotrophic abilities to 9, compared to the 7 known mixotrophic Alexandrium species. Furthermore, the Alexandrium phylogenetic tree based on the large subunit ribosomal DNA contained 3 large clades, each of which had species with and without mixotrophic abilities. Thus, the acquisition or loss of mixotrophic abilities in Alexandrium might readily occur.

A Study on the Characteristics of Naturalism in Fashion Design with the Changes of Times (자연주의 복식의 시대적 변천에 따른 디자인 특성에 관한 연구)

  • Kim Hee-Yeon;Kim Young-In
    • Journal of the Korean Society of Costume
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    • v.56 no.7 s.106
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    • pp.31-41
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    • 2006
  • The purpose of this study is to formulate a concept of naturalism in fashion and verify the design characteristics found in such designs via reviewing the concept of naturalism and its influence on dress making in different periods in history. The references from various academic fields including philosophy, literature and fine arts were used to examine how the naturalism was formulated over the years. This study was then to identify the naturalistic influences by closely examining various Western dress codes found in literature, publications and actual samples. The results of this study shows that the close examination of naturalism in fashion with the changes of times displayed the complex evolution process over the years, and they were classified by four distinctive categories; Retro, Ecology, Primitive and Ethnic. Naturalism in the contemporary fashion design showed higher frequency of adopting ecological and retro styles, especially retro style adoption being on the rise, combining wide range of partial components of each style. The color usage showed the skewed concentration on YellowRed, Red and Yellow colors with pale, light grayish and grayish tones.

NUMERICAL MODELLING OF SEDIMENT TRANSPORT IN CONNECTION WITH ARTIFICIAL GRAIN FEEDING ACTIVITIES IN THE RIVER RHINE

  • Duc Bui Minh;Wenka Thomas
    • Water Engineering Research
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    • v.6 no.1
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    • pp.17-30
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    • 2005
  • The bed evolution of the stretch of the River Rhine between km-812.5 and km-821.5 is characterised by general bed degradation as a result of the river training works and dredging activities of the last two centuries. The degradation of the river bed affects the water levels, and so the navigation conditions. To combat the erosion of the river bed with the aim to keep up the shipping traffic and to avoid the ecological system damages due to water level reductions, sand-gravel-mixtures were added to the river (so called artificial grain feeding activities). This paper presents the results of an application of a graded sediment transport model in order to study morpholodynamical characteristics due to artificial grain feeding activities in the river stretch. The finite element code TELEMAC2D was used for flow calculation by solving the 2D shallow water equation on non-structured grids. The sediment transport module SISYPHE has been developed for graded sediment transport using a multiple layer model. The needs to apply such graded sediment transport approaches to study morphological processes in the domain are discussed. The calculations have been carried out for the case of middle water flow and different size-fraction distributions. The results show that the grain feeding process could be well simulated by the model.

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Evaluation of Historic Breeding Habitats with a View to the Potential for Reintroduction of the Oriental White Stork (Ciconia boyciana) and Crested Ibis (Nipponia nippon) in Korea

  • Park, Shi-Ryong;Kim, Su-Kyung;Sung, Ha-Cheol;Choi, Yu-Sung;Cheong, Seok-Wan
    • Animal Systematics, Evolution and Diversity
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    • v.26 no.3
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    • pp.191-196
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    • 2010
  • The Oriental White Stork (Ciconia boyciana) and the Crested Ibis (Nipponia nippon) are wetland species listed as "Endangered" on the IUCN Red List of Threatened Species. The two species were once common on the Korean peninsula, but have experienced a severe population reduction in the past decades. Currently, they are officially extinct in Korea. At present, reintroduction programs to release the birds to the wild are in progress in Korea as well as in Japan. In this study, we surveyed the historic breeding sites of the two species using the literature and face-to-face interviews with local people as a step toward determining appropriate breeding habitats for reintroduction. We found 26 historic breeding sites for the Oriental White Stork in Chungcheong-do and Gyeonggi-do, but did not find any breeding sites for the Crested Ibis. These findings suggest that the Oriental White Stork was resident, while the Crested Ibis was a winter visitor to Korea. Based on these results, we discuss the possibilities for successful reintroduction of the two species in Korea.

Current Status of Mammal Fauna on Jindo Island, Korea

  • Oh, Hong Shik;Park, Seon Mi;Kim, Yoo Kyung;Han, Sang Hyun;Lee, Hwa Jin;Ha, Jeong Wook
    • Animal Systematics, Evolution and Diversity
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    • no.spc9
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    • pp.73-79
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    • 2016
  • In the present study, to explore the current status of mammals that inhabit Jindo Island, Jeollanam-do, South Korea, a survey was conducted from July 6 to July 9, 2016. Using several survey methods, such as Sherman's live trap, footprint, caves, excretions, and road-kill investigations, the mammals observed on Jindo Island were found to be from 5 orders and 9 families, including 12 species in total. Among them, three species of small mammals were Mogera wogura, Crocidura shantungensis, and Apodemus agrarius. Additionally, two legally protected species were found through excretion observations. Lutra lutra and Prionailurus bengalensis, which were designated to endangered wild animal classes I and II, respectively. The survey results can be used as a valuable resource for identifying the distribution and habitat status of mammals in the Jindo-gun area, as well as for building a database for ecosystem preservation.

The incidence of abnormalities in the fire-bellied toad, Bombina orientalis, in relation to nearby human activity

  • Kang, Changku;Shin, Yujin;Kim, Ye Eun;Moon, Jongyeol;Kang, Jae Yeon;Jang, Yikweon
    • Journal of Ecology and Environment
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    • v.39 no.1
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    • pp.11-16
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    • 2016
  • Declines in amphibian populations are occurring worldwide, and have been attributed to many factors, including anthropogenic environmental changes. One of the ramifications of such declines is abnormalities in many amphibian species. A strong association has been detected between human activities and abnormalities in amphibian populations, but studies on this association are largely focused on lentic species. In this study, it was analyzed whether the degree of local human activity was associated with the rate of abnormalities in Bombina orientalis which inhabited lotic environments. We found that the proportions of abnormalities in wild populations of B. orientalis increased, when i) the closest human land use was located within 100 m from the frogs' habitat, and ii) the proportion of human land use within a 300-m radius was high. Our findings suggest that human activity has a negative impact on the fitness of nearby amphibian populations, and that wild populations very close to human-induced disturbance are affected.