• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.3-3
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• 2004

One short core with length of 146cm(HB-107, at coordinates of $N51^{\circ}$11'37.5";$E100^{\circ}$24'45.6", from 229m water depth was subject of the present study. The sub-samples of the core were analyzed for the water contents (WC%), biogenic silica, identification of the main phases, grain size distribution, geochemistry and some physical properties of sediment(Wet density and Magnetic susceptibility) with aims of recording palaeo-environmental changes in Northem Mongolia. The evaluation of the geochemical and mineralogical proxies on palaeo-climated and palaeo-environmental changes are based on comparison to the behvior of biogenic silica through core, as later one had been showed itself, as good indicator of the climate and environmental fluctuation. Age model of the investigating core based on previously C 14 dated core HB105 taken from the central part of the Hobsgol Lake and the result had been published elsewhere. The core consists of two litological varieties : upper diatomaceous silt, lower clay. According to the age model the upper diatomaceous silt formed during the Holocene, lower caly-during the late Pleistocene glacial period. The geochemistry and phase identification analysis on the core samples are resulted in determining main minerals that form the bottom sediments and their geochemistry. The main include quartz, felspar, muscovite, clinochlore, amphibole and carbonate phase(dolomite and calcite). Through the core not only occur the relative quantitative changes of the main phases, but also happen that the carbonate phase completely disappear in diatomaceous silt. This is believed to be related to the lake water salinity changes, which occurred during the trassition period from Pleistocene glacial-to the Holocene interglacial. These abrupt changes of the mineralogy have been clearly traced in geochemistry of sediments, specially in calcium concentration, which is high in lower clay and low in upper diatomaceous silt. That means, geochemistry and mineralogy of the bottom sediments can be used as proxy data on palaeo-climate and palaeo-environmental changes.

• Journal of Environmental Science International
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• v.16 no.9
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• pp.1027-1037
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• 2007

The purpose of this study was to investigate the flora of Mt. Bongrae in Busan from February 2004 to May 2005. The flora in the surveyed area were identified 291 taxa that belonged to 82 families, 201 genera, 251 species, 35 varieties, and 5 forms. Among them, evergreen broad trees were identified 21 taxa, naturalized plants 30 taxa, especial plants decided by Ministry of Environment 24 taxa. By the vegetation of each slope, in northeast slope, it was dominated such as Pinus thunbergii community, Chamaecyparis obtusa community, Amorhpa fruticosa community, Trachelospermum asiaticum var. intermedium-Hedera rhombea community, north-northeast slope, it was distributed both Pinus thunbergii community and board-leaved tree community. In the southwest slope of coast site, it was presented plantation plants, according to altitude distributed such as natural vegetation, evergreen broad trees, warm-temperate plants. In southeast slope, it was to represent secondary vegetation such as Alnus firma community as a forest fire. Underside was mainly to search herbs such as naturalized plants and cruciferous family as a vegetable garden. In northwest slope, it was searched trees such as Pinus thunbergii community, Lindera obtusiloba, Styrax japonca, Prunus sargentii, Aralia elata, Zanthoxylum piperitum, Akebia quinata and herb layer such as Osmunda japonica, Allium thunbergii, Liriope platyphylla, Corydalis ochotensis, Scilla scilloides, Viola orientalis. Around the top, it was distributed such as Rhododendron mucronulatum-Rhododendron schlippenbachii community, Carpinus coreana, Viburnum erosum, Sorbus alnifolia.

• The Korean Journal of Ecology
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• v.7 no.3
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• pp.132-157
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• 1983

This study was performed to investigated the flora and vegetation of Kokum-do island from July 1982 thru December 1983; and the findings hereof are summarized as follows: The flora investigated thereform comprises 737 species whih are classified into 128 families, 466 genera, 651 species, 79 varieties and 7 formae; and those which are worthy of close attention among the same include such endemic species of Korea as Celtis choseniana, Corylopsis coreana, Carpinus tschonoskii var. eximia and Tricyrtis dilatata, and a few plants, to be distributed in the north, such as Lilium distichum, Girardinia cuspidata and Orostachys sikokianus. Now that the said island belongs to the warm temperate zone, the distribution thereof consists of 120 species of evergreen plants including 74 species of evergreen broadleaf trees. The rich distribution of evergreen broadleaf trees in the island is thanks to the plantation thereof by the public organizations for scenic beauty. The destruction of flora in this island was caused by felling, fire nization and other human activities around 1940, and in particular, has been correlated with the population densiity of Yonhong-do, Sanghwa-do, and Hahwado islets; and that of top soil and ground vegetation in he quarry area of Ojon-ri town resulted from the collection of natural rocks an stones. It is evaluated as necessary that such evergreen broadleaf trees as Castanopsis cuspidata var. thunbergii, Machillus thunbergii and Ligustrum japonicum of Hyongje-do. Chun-do, Tok-do, Taech'wi-do, and Soch'wi-do islets, andPhyllostachys bambusoides, Caesalpinia japonica and Albizzia julibirssin of Kokum-do island, and Machillus thunbergii of Hongryon-ri town be under protection. The average DGN of the whole archipelago proves to be 5.84, which shows the tendency of the inverse proportion to the number of resident population per unit area. The pteridophyta distributed in this island comprises 39 species, and the coefficient of cryptogam as to the destruction of vegetation shows a high value of 1.4 which is regarded as indicating the diversified distribution of pteridophyta, forestbed shade plants under the forestbeds of some wellpreserved lots of this island. The naturalized plants, distributed in this island, were found out comprising a total of 23 species, and the Urbanization Index(UI) as to the destruction degree of natural vegetatioin shows a low value of 20.9.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.27-33
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• 1969

This study was carried out to investigate the variation of mulberry yield in various parts of mulberry field. The results obtained from the study are summarized as follows. 1. For all the varieties, higher yield was observed side part than in the middle part. 2. With respect to the direction of field, the side faced south produced the highest yield, which was followed both side parts faced east and west. The side part fated north also produced relatively high yield. 3. No significant difference in yield was obtained between the central part and the near the each side, even the former seemed to be some what higher in yield than the latter. 4. Such a variety as Kaeryangsuban havins small leaves on many twigs with small internodes appeared to have more side effect than the otherwise variety, i.e. Rosang. 5. The variety Kaeryangsuban, showed more side effect in spring than in Autumm, however Rosang showed reversed effect. 6. Similar results were obtained in the leaf dry weight. 7. As a conclusion, it can he an important factor to increase yield to set up the mulberry field in east and west resulting less side effect.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.407-413
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• 2003

The geology of the Apdong Nb-Ta deposit, is hosted by alkali metasomatites, consist of Upper Proterozoic sedimentary rocks, alkali syenites(Hoamsan intrusive) of Phyonggang Complex(late Paleozoic to early Mesozoic), Jurassic granite and Quaternary basalt. Alkali syenites are distinguished as alkali amphibole-pyroxene syenite, alkali amphibole-biotite syenite, biotite-nepheline syenite, biotite syenite, and quartz-alkali amphibole-pyroxene syenite. Alkali metasomatites are the products of intense post-magnatic metasomatism, and form the Nb-Ta ore bodies as the belt, irregular vein and lenticular types in the southern part of Hoamsan intrusive. The ore mineralization is characterized by the occurrence of pyrochlore, zircon, and small amounts of columbite, fergusonite. magnetite, fluorite, molybdenite, ilmenite, titanite, apatite, and monazite. Pyrochlore is one of the niobium/tantalum oxides and contains substantial amounts of rare earths and radioactive elements. The compositional varieties of pyrochlore can be defined: (1) enriched in tantalum, uranium and cerium, (2) substantially tantalum- and fluorine-poor, and (3) enriched in thorium or barium. The geochemical characteristics, ore textures and mineral occurrences indicate that alkali metasomatism of the mineralizing fluid was the dominant ore-forming process.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.399-409
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• 2017

The rapid increase of naturalized plants causes disturbance of the ecosystem. The purpose of this study is to identify the reality of naturalized flora in Jeolla-do. A total of 830 sites were studied in 2016. These naturalized plants consisted of 189 taxa in total, belonging to 38 families, 116 genera, 181 species, 2 forms and 6 varieties. According to the results of the analysis based on place of origin, 75 taxa were from Europe, and 59 taxa were from North America. According to the analysis of the ecological characteristics, compositae had the highest diversity among 31 families, with 44 taxa, followed by Gramineae, with 24 taxa, and Leguminosae, with 10 taxa. Naju-si had the highest diversity among 36 counties, with 77 taxa. This study identified 37 (Jeollanam-do) and 30 taxa (Jeollabuk-do) not listed in the preceding literature in Jeolla-do. We found a lots of differences between flora's databases of previous studies resulting from the naturalized plant definition.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.3
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• pp.9-20
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• 2009

The naturalized plants in the Gwangyang Steel Works were listed 70 taxa; 18 families, 51 genus, 66 species, 3 varieties and 1 form. by field survey. The naturalized plants divided into pattern by survey of annual plants ratio is 31 taxa (44.3%) by life form spectrum and perennials is 23 taxa (32.9%), biennials is 13 taxa (18.5%), two trees (Robinia pseudoacacia, Alianthus altissima) and one shrub (Amorpha furticosa) were founded. According to analysis results form place of origin, Europe covered 26 taxa (37.1%), North America covered 23 taxa (32.8%). Naturalized degree 3 plants, as common but not abundant, founded as 24 taxa (35.0%) were hold most highly ratio, naturalized degree 1 plants founded as 3 taxa (4.0%) were hold lowest. Introduction period 1 covered 31 taxa (44.3%) have had highest score and period 2 covered 11 taxa (15.7%) have had lowest scores. In addition, the urbanization index based on 271 taxa was 25.8% and 2 taxa (Solanum carolinense, Ambrosia artemisiaefolia) is growing in the Gwangyang Steel Works by ecosystem disturbing wild plants. Meanwhile, Ambrosia artemisiaefolia have confirmed into several tens~hundred in the Gwangyang Steel Works were damage the human body of plants develop an allergy to pollen. Solanium carolinense have composed several large communities about $10m{\times}10m$ ($100m^2$) and hold a dominant position, so management plan of the sequel of monitoring them might be required.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.2
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• pp.103-113
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• 2014

Under climate change, it is likely that the suitable area for forage crop cultivation would change in Korea. The potential cultivation areas for italian ryegrass (Lolium multiflorum L.), which has been considered one of an important forage crop in Korea, were identified using the EcoCrop model. To minimize the uncertainty associated with future projection under climate change, an ensemble approach was attempted using five climate change scenarios as inputs to the EcoCrop model. Our results indicated that most districts had relatively high suitability, e.g., >80, for italian ryegrass in South Korea. Still, suitability of the crop was considerably low in mountainous areas because it was assumed that a given variety of italian ryegrass had limited cold tolerance. It was predicted that suitability of italian ryegrass would increase until 2050s but decrease in 2080s in a relatively large number of regions due to high temperature. In North Korea, suitability of italian ryegrass was considerably low, e.g., 28 on average. Under climate change, however, it was projected that suitability of italian ryegrass would increase until 2080s. For example, suitability of italian ryegrass was more than 80 in 10 districts out of 14 by 2080s. Because cold tolerance of italian ryegrass varieties has been improved, it would be preferable to optimize parameters of the EcoCrop model for those varieties. In addition, it would be possible to grow italian ryegrass as the second crop following rice in Korea in the future. Thus, it merits further study to identify suitable areas for italian ryegrass cultivation after rice using new varieties of italian ryegrass.

• Korean Journal of Plant Taxonomy
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• v.51 no.1
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• pp.49-99
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• 2021

Gwangdeoksan Mountain (699.3 m) is the highest border mountain between the two cities of Chungcheongnamdo Province, Cheonan and Asan, Korea. In this study, we investigated the flora of Gwangdeoksan Mt. from April of 2015 to October of 2017. Through 20 independent field investigations, we identified and tallied a total of 428 species, 9 subspecies, 30 varieties, and a forma in 287 genera and 97 families. Of a total of 468 taxa, 128 taxa in 112 genera and 58 families were found to be Korean endemic species (7 taxa), floristic regional indicator species (45 taxa), rare or endangered species (3 taxa), species subject to the approval of outbound transfer (73 taxa), and alien or ecosystem disturbing species (32 taxa). The flora of Gwangdeoksan Mt. can be divided into four distinct floristic subregions, with higher diversity in the north-facing subregion. The complex flora of Gwangdeoksan Mt., emerging at the edge of two floristic regions of the Korean peninsula, may represent a significant conservation priority and a topic for future ecological and geographical studies.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.69-79
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• 2013

We investigated the flora of Mt. Namdeogyu, southern regions of Deogyusan National Park, from April of 2011 to September of 2012. The number of vascular plants in this area were summarized as 507 taxa, including 102 families, 296 genera, 444 species, 8 subspecies, 49 varieties, 6 forms. Among the recorded taxa, Korean endemic plants were 9 species and the floristic regional indicator plants were 80 taxa including 3 taxa in grade V, 3 taxa in grade IV, 19 taxa in grade III category. The rare and endangered plants which was designated by Korea Forest Service were 15 taxa comprising 1 endangered species (EN) of Rhododendron tschonoskii, 5 taxa of vulnerable (VU) such as Cynanchum inamoenum, Lilium cernuum, Gastrodia elata, Bupleurum euphorbioides, Paeonia japonica, and 9 least concerned (LC). In addition, the subalpine plants of the region were summarized as 24 taxa, and Mt. Deogyu area inclunding the Mt. Namdeogyu was suggested as the north most limits line of the distribution for 2 taxa, Abies koreana and Rhododendron tschonoskii, and as the south most limit of the distribution for Bupleurum euphorbioides.