• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.260-266
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• 1996

To find out the residual effect of phosphate fertilization level on the dry matter yield and nutrient plloductivity of pasture plants, this experiment was arranged as a randomized complete block design with six treatments(0-0, 50-50, 100-65, 150-65, 200-65 and 250-65kg $P_2O_5$), those were composed of three $P_2O_5$ fertilization level(0,50 and 65kg $P_2O_5$ after phosphate fertilization trial with six treatments(0, 50, 100, 150, 200 and 250kg $P_2O_5$/ha) from 1989 to 1992, and conducted at hilly land in Kwangju, Kyonggi Province from 1993 to 1994. The results obtained are summarized as follows : As the available phosphate of soil increase, the early growth and cover degree of pasture plants wintered were more favorable. With 150-65kg $P_2O_5$ application for two years, the average dry matter yield of grasses, 9,862kglha was similared to that of 200-65kg $P_2O_5$/ha. The crude protein and energy productivity of pasture plants tended to increase as available phosphate of soil was increased, but those were not different between 150-65 and 250-65kg P 2 0 4 a Efficiency of $P_2O_5$ was highest at $P_2O_5$ 150-65kg/ha fertilization, wHich produced dry matter 11 1.8kg. net energy lactation(NEL) 67 1.2M.f per I kg P205. Therefore, phosphate fertilization is recommended strongly application with 150kg/ha for three years after pasture establishment, and then 65kg/ha for two years a reasonabl management in hilly grassland.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.187-200
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• 2003

This study was conducted by China along with the Tumen River, which cuts between of North Korea and China. As a result 92 family, 287 genera, 470 species, 57 variety 4 formas, total 531 taxa of vascular plants were identified. The surveyed area was include the region that had various vegetation such as upper swampy land, seashore dune, a river, a high mountain grassy plain, deciduous tree zone and evergreen coniferous forest zone. The specfic plants which is protected by The Natural Environmental Preseration Act appeared to 6 taxa, and rare and endangered plants conserved by Forestry Administration were found 21 taxa in these areas. Among them Lilium cernum, Jeffersonia dubia, Acanthopanax senticosus could be regarded as very important one for chinese medicine. Picea koraiensis, Larix gmelini var. principis-ruprechtii, Populus koreana, Betula fusenensis, Ulmus pumila, Ledum palustre var. diversipilosum, Rhododendron parvifolium, Vaccinium uliginosum, Astragalus membranaceus, Aquilegia flabellata var. pumila, Carex gotoi, Carex capricornis etc. are not distributed in the South Korea.

• Journal of Environmental Science International
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• v.32 no.12
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• pp.915-923
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• 2023

The purpose of the study is to explore strategies to revitalize the distribution of landscaping plants in Gangwon State (hereinafter referred to as Gangwon-do). To understand the current distribution status and perception of landscape materials in Gangwon-do, a survey was conducted on producers and consumers focusing on cultivation area and method, cultivated species and quantity, purchase species and quantity, and purchase area. Producers often cultivated open land, and in the case of trees and shrubs, most of them cultivated <5 species. On the other hand, consumers preferred field cultivation products when purchasing trees and shrubs. Approximately 6-10 species of trees and shrubs were preferred for a single purchase, confirming an imbalance in the supply and demand of landscaping plants. In addition, both producers and consumers had a positive perception of landscape plant transactions in Gangwon-do; however, the dissatisfaction factors for producers included a small consumer base and difficulties for them in securing standards and quantities. Based on these results, it is necessary to establish a platform that can interconnect producers' landscape plant cultivation information with consumers' requirements to rejuvenate the landscape plant distribution market and enhance competitiveness in Gangwon-do. In addition, this platform is expected to have a positive impact on improving the quality of landscaping plants, setting reasonable prices, and increasing domestic demand in Gangwon-do by providing opportunities for cultivation, promotion, and marketing education through producer support projects.

• Korean Journal of Ecology and Environment
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• v.50 no.2
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• pp.254-265
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• 2017

To elucidate occurrence patterns of naturalized plants in agroecosystems, we surveyed flora in uplands, orchards and rice paddy fields in middle regions (Gyeonggi-do and Chungcheong-do) of Korea in summer and fall from 2013 to 2015. Our results showed that there are 77 species of naturalize plants in 54 genera and 20 families of vascular plants among total 420 species occurred in the agricultural areas composing 18.3% of naturalized index. Community compositions of both native and naturalized plants were different among agricultural types. We suggested that Cerastium glomeratum Thuill., Bidens frondosa L. and Erigeron philadelphicus L. are capable of dispersal to other regions based on our results with getting to broaden distribution of naturalized plants. The mean naturalized index was the highest in the upland (25.1%) followed by in the orchard (23.0%) and the paddy field (16.1%), while the mean number of naturalized species was the highest in the orchard (21.8 species) followed by in the upland (16.6 species) and paddy field (10.3 species). The numbers of naturalized plants in the orchard were increased along with increasing size of the agricultural land and decreasing ecological area rate. In addition, the number of native species was significantly correlated with the number of naturalized species in the upland. Our results would provide useful information to manage dispersion of naturalized plants in agricultural ecosystems.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.374-387
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• 2020

This study was conducted to provide basic data for monitoring the trend of ecosystem change and establishing management plans for wetland protection areas by understanding the status of naturalized plants. In 21 wetland protection areas, 129 taxa, including 10 invasive alien species, were recorded. The naturalized plants appeared mostly as 71 taxa in the Chimsil wetland and were not observed in the Moojechineup and Sumeunmulbaengdui wetlands. Among the naturalized plants, 42 taxa (32.6%) originated from North America. Annual and biennial plants accounted for 68.2% (88 taxa). The frequencies of occurrence of naturalized plants growing in dry secondary grasses such as Erigeron annuus and Trifolium repens were high, and clonal plants that propagated by making stolons and struck roots accounted for 19.4% (25 taxa). The naturalized and urbanization indices showed positive correlations with location factors such as wetland, agricultural land, and used area. However, a negative correlation was found between altitude and forest. Therefore, a management plan that synthetically considers the occurrence frequency and growth characteristics of naturalized plants as well as the locational characteristics of wetland protection areas is required.

• Journal of Environmental Science International
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• v.18 no.4
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• pp.463-471
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• 2009

A study on vegetation in the Mangyeong River and Dongjin River basins and the surrounding regions of the Saemangeum Reclaimed Land was conducted in a series of efforts to determine the expected ecological changes in the salt marshes, to restore their vegetation, to explore the restoring force of halophyte, to examine the community mechanism and, ultimately, to rehabilitate marshy land vegetation along the lakeside, coastal dune and salt marshes of the Saemangeum Project Area. The findings of the study may be summed up as follows: Five species such as Suaeda japonica, Salicornia herbacea, Atriplex gmelini, Aster tripolium and Suaeda asparagoides that are mostly distributed in the estuary of the Saemangeum Reclaimed Land were analyzed to examine the mechanism of halophyte to maintain their community. To find out the strategies of plants for survival and the cause of forming community structure, a research was made as for appearance ratio of biomass, root lengths and germination. With regard to biomasses of halophyte, the biomass of Suaeda japonica increases rapidly, while Salicornia herbacea adopts a strategy of unstable growth pattern by which the biomass increases slowly in parallel with its slow speed of growth since initial appearance of young sapling. In contrast, Suaeda asparagoides, Atriplex gmelini and Aster tripolium choose to adapt themselves to environment promptly by being transformed into life form of annual or biennial plant, a pattern that is presumed to be favorable and stable for survival in the later stage of growth. In short, there is a sharp distinction among the 5 species: i.e. Suaeda japonica that begins to grow fast in the length of surface and underground section but slows down from the mid-stage on; Salicornia herbacea that grows slowly in the beginning step but starts to step up from the middle onward; Atriplex gmelini and Aster tripolium growing slowly in the initial stage but fast later on; and Suaeda asparagoides that turns from the constant growth in the beginning to rapid growth in the later period. The outcomes of the analysis into status of growth and influencing factors of Suaeda japonica in the sowing field that is most widely prevalent in the Saemangeum Reclaimed Land as a sort of ecological pioneer in the salt marshes showed that the average size of grass lands, density and number of individuals increase in the natural sowing field as well as in the plowing field regardless of their physical as well as physico-chemical features of the soil as the season progresses from June to October of a year.

• Economic and Environmental Geology
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• v.29 no.1
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• pp.45-55
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• 1996

Although the Dongjin Au-Ag-Cu mine had been abandoned since about forty years ago, the results of this study on the dispersion patterns and contamination level of heavy metals in the hydrologic system flowing via the waste rump show that the environmental impacts from the mine wastes are still significant. The stream water in the vicinity of the waste rump is severely acidified (pH 3.8 to 4.4) and highly enriched in various dissolved heavy metals. The heavy metal contents of the stream water and stream sediments are systematically attenuated with increasing distance from the mine area. However, it is worth to note that continuous attenuation of heavy metal contents in both media were reenriched in downstream area more than 800 m apart from the mine because it can be acted as a secondary source of heavy metal pollution. The heavy metals, especially Cd, Cu and Zn of polluted downstream sediments mainly occur in Fe-Mn oxides and organic materials, which indicates that these elements are the main pollutants from the waste rump of the Dongjin mine. The heavy metal contents of crops, such as sesame, perilla, red Pepper and brown rice, collected from the polluted farm land in the downstream area are lower than those of land plants from stream sides, but significantly higher in Cd, Cr, Cu and Zn than those from the unpolluted farm land. Especially, almost all of the crops in polluted farm land have been severly contaminated by Cd (>0.4 ppm). On the other hand, the heavy metal contents of the crops collected from refreshed farm land by means of a soil addition method shows significantly lowered level comparing with those of polluted area, which indicates that a soil addition method was effective for the refreshment of polluted farm land by toxic metallic pollutants. Wormwoods from this area showed very high contents in a11 the heavy metals even in unpolluted area (Cd > 1 ppm, Cr > 1 ppm, Cu > 11 ppm, Pb> 4 ppm, Zn > 55 ppm), indicating that a special caution must be payed when one takes ingest them.

• Korean Journal of Environment and Ecology
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• v.25 no.2
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• pp.166-174
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• 2011

This study was carried out to investigate the actual vegetation and Degree of Green Naturality(DGN) in Naejangsan National Park in 2010. The actual vegetation of the surveyed site were classified into twelve plant communities and the others. Secondary forest were classified into eight plant communities; Pinus densiflora community, Deciduous broadleaf forest, Quercus mongolica community, etc. Afforested lands were classified into four forest types: P. rigida -P. densiflora forest, P. rigida forest, etc. The area of DGN 8 consisted of 60.58% while the area of DGN 9 consisted of 3.62% when compared with land area in Naejangsan National Park. The exotic plants needs to be managed for recovery of natural landscape and biological diversity in Naejangsan National Park.

• Land and Housing Review
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• v.9 no.1
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• pp.1-9
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• 2018

As the government announced Real Estate Policies on August 02, most areas except for Seoul cities face increasing business risks. Moreover, the government control over financial sectors' loan leads to the highly possible contraction of new distribution markets. The market trend could bring about the reduction of new demand in PF (Private Financing) business that large construction companies mainly concentrate on, and even the business already obtained has a high risk of being distributed, which could result in substantially low profitability. The currently unstable financial structure of most construction companies is caused by the hike of the prime cost of foreign plants except for that of a few construction companies. If PF (Private Financing) business also faces a difficult situation in such a financial condition, even large construction companies come to have the high possibility of a deficiency in credit rating. Accordingly, the major business that large construction companies concentrate on needs the sufficient business review. It is desirable to make a bid for business guaranteeing stability rather than business solely in consideration of profitability, when participating in a competition for a new construction contract.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.667-675
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• 2008

As a large construction such as highway, dam, reclaimed land etc. increase in number more and more, large amount of fill materials are required. However, it's difficult to obtain it because of environmental problems and economical efficiency. A alternative plan is to utilize a gypsum which is a by-product yielded from chemical plants and verify suitability to use gypsum as fill materials. Therefore, a characteristic of compaction for gypsum is analyzed and construction methods are given regard to this characteristic from construction of dike using gypsum. Based on the results obtained, it is found that moisture of gypsum in compaction should to be more dry side of O.M.C(optimal moisture content) because of sponge phenomenon. When gypsum is used to fill materials, standards of compaction should be decided from laboratory test.