• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.439-442
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• 2001

This study has been conducted from April 25, 1999 to June 25, 1999 in Jeju Province in order to determine the influence of seeding date on growth, yield and chemical composition of Kenaf (Hibiscus cannabinus L.) Delaying the seeding date from April 25 to June 25 decreased the plant height of Kenaf from 278.5 cm to 205.7 cm. As for the number of leaves, number of withering leaves, number of branches, and stem diameter decreased as the seeding date was delayed. As the seeding date was delayed, fresh forage yield decreased from 98.5MT/㏊ to 45.9MT/㏊, dry matter yield from 20.7MT/㏊ to 8.2MT/㏊, crude protein (CP) yield from 2.9MT/ha to 1.3MT/ha and total digestible nutrients (TDN) yield form 1l.6MT/㏊ to 5MT/㏊. However, both leaf yield and stem yield were nearly the same tendency. Delaying the seeding date from April 25 to June 25 increased crude protein contents of leaves from 21.5％ to 24.4％, crude fat contents from 5.2％ to 6.1％, nitrogen free extract (NFE) contents form 39.9％ to 41.2％ and TDN contents from 64.3％ to 69.7％. However, delaying seeding date decreased crude fiber contents from 20.8％ to 17.5％, and crude ash contents from 7.9％ to 7.0％. Based on the these findings, optimum seeding date for forage production of Kenaf seems to be about 25 April in atmospheric phenomena and volcanic ash soils of Jeju island.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.49-49
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• 2019

국립수목원은 열대유용식물의 BT산업 원천소재 확보 제공을 목적으로 열대자원연구센터를 건립하여, 열대 및 아열대 전시원을 관리하고 있다. 온실의 특성상 일반 재배환경과는 다르게 여러 종류의 식물의 혼합 식재되어 있는 특성이 있어서 농업환경과 달리 해충의 급격한 돌발에 의한 온실 전체적인 피해의 위험성이 적은 반면에 안정된 환경으로 인해서 해충의 취약한 몇몇 수목의 경우 해충이 급격히 늘어날 수 있다. 본 실험은 여러 종류의 식물이 혼재되어 있는 수목 온실 내에서 생물적 방제를 이용하여 주요 해충류인 진딧물류 및 가루 깍지벌레, 잎응애류 방제 가능성을 타진하고자 진행되었다. 진딧물이 집중적으로 발견된 열대식물 5종(Acalypha hispida, Justicia gendarussa, Hamelia patens, Ficus petersii, Hibiscus rosa-sinensis)을 중심으로 천적 방사 및 Banker plant 설치를 진행했다. 최초 조사일인 2015년 3월 10일, Tropical 1에 진딧물류의 발생이 많이 확인되어 포식성 천적인 미끌애꽃노린재를 투입했다. Tropical 2는 2015년 3월 17일 기생성 천적인 콜레마니진디벌과 선발된 Banker plant를 적용하여 방제 되었다. 철모깍지벌레가 발견된 열대식물 3종(Sanchezia parvibracteata, Brillantaisia lamium, Pseuderanthemum atropurpureum)을 중심으로 적용 천적으로 어리줄풀잠자리, 애홍점박이 무당벌레와 깍지무당벌레를 선별했다. 천적을 대상으로 철모깍지벌레에 대한 포식능력을 조사했으며 애홍점박이 무당벌레가 어리줄풀잠자리 보다 2.8배, 깍지무당벌레보다 2.9배 포식능력이 뛰어남을 확인했다. 잎응애류가 발견된 열대식물 2종(Acalypha wilkesiana, Erythrina caffra)은 천적으로 사막이리응애와 칠레이리응애를 적용하였다. 괭이밥응애 성충과 알의 포식력을 검증한 결과 사막이리응애가 괭이밥응애를 먹이로 증식이 가능한 것으로 확인되었다. 괭이밥, 괭이밥응애, 사막이리응애를 효과적으로 조합한 응애류 방제를 위한 새로운 Banker plant의 개발 가능성을 확인할 수 있었다. 연구는 열대온실의 열대식물 관리에 대한 생물학적 방제의 지속적인 모니터링을 통해 종합적 방제의 관리 자료로 이용되어 새로이 온실을 조성하는 경우 식재기반조성에 실질적인 도움을 줄 수 있으며, 추후 열대식물의 자원 식물로서의 활용성을 높일 수 있다.

• Korea Science and Art Forum
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• v.37 no.5
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• pp.239-248
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• 2019

This study started from the need to improve one of shortcomings of synthetic PVAc adhesives - potential physical harm and environmental hazards to the workers or their users. As a matter of fact, PVAc adhesives are currently mainly used because of their convenience and economy for the production of woodcrafts. The purpose of this study was to develop natural adhesives through research on natural adhesives in step with the current increase of societal attention to environmental friendliness and rapid surge in their demand in the face of such problems. So, the study attempted research on the bases to develop natural adhesives for woodcraft, using cellulose extracts from wood - natural adhesive material. The findings of the study were as follows. Firstly, natural adhesives showed the improved effect in the field of adhesive strength, a basic physical property by 0.2 - 4 times compared with the existing materials and the study confirmed they had the similar or stable pH value. Besides, they had good reversibility, demonstrating their basic physical property as a natural adhesive for woodcraft. While, their durability to ultraviolet ray degradation also showed an excellent result value being better by 1.5 - 8.5 times than the existing materials. The study expects natural adhesives with improved and better performances compared with the existing materials could be developed, if further research on adhesive strength, antibiosis, conservative property were to continue by developing refinery technology for cellulose extracts from wood and rendering the functionality to them.

• Korean Journal of Environment and Ecology
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• v.36 no.1
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• pp.30-55
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• 2022

This study conducted a flora survey in the areas of Mt. Sambong (282m) and Mt. Jaung (263m), located in Paju-si, Gyeonggi-do. A total of 434 taxa, including 6 forms, 34 varieties, 11 subspecies, 383 species, 271 genera, and 94 families, were surveyed in the two mountain areas. The ferns were identified as 24 taxa from 10 families, the gymnosperms as 8 taxa from 2 families, the dicotyledonous plants as 322 taxa from 73 families, and the monocotyledonous plants as 80 taxa from 9 families. Five taxa, including Salix koriyanagi, Cimicifuga heracleifolia, Forsythia koreana, Paulownia coreana, and Hemerocallis hakuunensi, were identified as the Korean endemic plants. Eight taxa, including Cimicifuga heracleifolia, Tylophora floribunda, and Iris minutiaurea as Vulnerable species, andAristolochia contorta, Viola diamantiaca, Lithospermum erythrorhizon, Lilium distichum, andArisaema heterophyllumas Least Concern species, were designated as rare and endangered plants designated by the Korea Forest Service. The invasive alien plants were 40 taxa, including Rumex crispus, Phytolacca americana, Cerastium glomeratum, Silene armeria, Chenopodium album, Chenopodium ficifolium, Magnolia obovata, Potentilla supina, Amorpha fruticosa, Medicago sativa, Robinia pseudoacacia, Trifolium repens, Euphorbia supina, Hibiscus trionum, and Oenothera biennisaccounting for 9.2 percent of the 434 taxa of the surveyed plants. As this area is a mountainous area close to settlement facilities, it is believed that ecological preservation measures and measures of specialized plants should be implemented.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.258-264
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• 2023

The greenhouse gas (GHG) emission assessment of kenaf pellet, produced from locally generated kenaf residues in South Korea, has been studied based on the EU RED-II methodology for calculating GHG impact of biomass fuels. Based on the production pathway of kenaf residue pellet and emission coefficients from EU JRC report, the life cycle GHG emission of kenaf residue pellet is assessed as 3.0 gCO₂eq/MJ_pellet and the life cycle GHG emission of electricity generated from kenaf residue pellet is assessed as 11.9 gCO₂eq/MJ when electrical efficiency of final conversion is 25%. The potential GHG emission reduction of electricity produced from kenaf pellet is 90.3% compared to the domestic electricity emission factor 42.8 kgCO₂eq/MWh. Also, the electricity produced from kenaf pellet can reduce at least 59.6% of GHG emission compared to the electricity produced from imported wood pellets.

• Korean Journal of Environment and Ecology
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• v.38 no.4
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• pp.354-366
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• 2024

Hibiscus hamabo, the northernmost semi-mangrove species in East Asia, presents an important case study for examining climate change's impact on temperate ecosystems and shifts in Korea's subtropical vegetation. This study investigates vegetation characteristics of H. hamabo and evaluates environmental factors influencing their distribution. H. hamabo communities are classified by regional and coastal types. Group I is found in depressed areas within deep bays, cohabiting with herbaceous halophytes. Group II develops along coasts with exposed bedrock or on gravelly coasts, cohabiting with tide tolerance vine shrubs. Group III in Japan encompasses a broader range of coastal environments compared to Korea. A monospecific population with over 100 individuals appeared in this group. this study reveals that precipitation of warmest quarter is the most important environmental factor affecting the distribution of H. hamabo communities. This research analyzes the influence of climatic variables in the distribution of semi-mangrove species, contributing to our understanding of ecological responses to climate change.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.615-623
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• 2001

A study of mammary function in relation to glucose metabolism of first lactation Bali cows on grass-legume diets was carried out using 12 primiparous cows (initial BW $263.79{\pm}21.66kg$) for 16 weeks starting immediately post calving. The animals were randomly allocated into 4 dietary treatment groups R1, R2, R3 and R4, receiving from the last 2 months of pregnancy onwards, rations based on a mixture of locally available grass and legume feed ad libitum. On a DM basis R1 contained 70% elephant grass (PP, Penicetum purpureum) plus 30% Gliricidia sepia leaves (GS), R2 was 30% PP plus 25% GS supplemented with 55% Hibiscus tilliacius leaves (HT, defaunating effect), R3 and R4 were 22.5% PP+41.25% GS+11.25% HT+25% concentrate, with R4 supplemented with zinc-diacetate. TDN, CP and zinc contents of the diets were 58.2%, 12.05% and 18.3 mg/kg respectively for R1, 65.05%, 16.9% and 25.6 mg/kg respectively for R2, 66.03%, 16.71% and 29.02 mg/kg respectively for R3 and 66.03%, 16.71% and 60.47 mg/kg respectively for R4. Milk production and body weights were monitored, an energy and protein balance trial conducted, overall glucose kinetics parameters assessed, mammary blood flow (MBF) and metabolite arteriovenous differences (${\Delta}AVs$) measured to get uptake data and mammary performance relationships. Parameters of glucose kinetics at peak lactation or during dry condition were not affected by ration quality. Glucose pool size, space of distribution and flux increased by 61.77, 62.26 and 82.08%, respectively, during lactation compared to the dry period. Mean glucose flux of lactating Bali cows was $5.52mg/min.kgBW^{0.807}$ which resembles the range of values of temperate dairy cows. Calculation showed that glucose requirements for maintenance, milk lactose and fat-glycerol synthesis, and the formation of NADPH reached 461.69 g for a yield of 1 kg/d or equal to 320.62 mg/min, which was less than the average glucose flux of lactating Bali cows of 481.35 mg/min. Mammary blood flow (MBF) values ranged from 56 to 83 l/h for the different treatments and the ratio MBF per kg milk produced improved from av. 1540 l/kg for R1 to av. 967 l/kg for R4 treated cows. Mammary glucose uptake ranged from 6.27 to 12.03 g/h or 120 to 140 g/kg milk. Glucose uptake was mass-wise 2 to 4 times the amount secreted as lactose, which indicated values less than the calculated mammary glucose needs and that little lactose was synthesized. The excess glucose taken-up was used for other metabolic processes. Linear relationships between metabolite ${\Delta}AVs$ and arterial blood plasma concentration [A] showed that in Bali cows triglycerides (TG), phenylalanine (Phe) and tyrosine (Tyr) have high coefficients of determination, i.e. 0.77, 0.81 and 0.69, respectively. For glucose, the relationship is quadratic with an $R^2$ value of 0.49. It was concluded that lactose synthesis was inadequate, which led to a speculation that milk yield could be improved by increased lactose synthesis.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.45-52
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• 2015

We obtained the following results from investigation on vegetation damage from 5 to 6 August, 2013, about one year after an accident that hydrofluoric acid leaked from a chemical maker, Hube Globe in Gumi. Pinus densiflora and Pinus strobus showed very severe damage. Ginko biloba, Quercus acutissima, Pinus rigida, Salix glandulosa, Hibiscus syriacus, and Lagerstroemia indica showed severe damage. Quercus variabilis, Lespedeza cyrtobotrya, and Miscanthus sinensis showed moderate damage. Quercus aliena, Smilax china, Arundidinella hirta, Ailanthus altissima, Robinia pseudoacacia, and Paulowinia coreana showed slight damage. We did not find any plants without leaf damage around there. This result means that fluoride damage still persists in this area as was known that fluoride remains for a long time in air, soil and water and exerts negative effects at all levels of an ecosystem. In addition, fluoride content contained in plant leaf depended on the distance from a fertilizer producing factory and vegetation damage tended to proportionate to the concentration in the Yeocheon industrial complex. In these respects, a measure for removal or detoxification of the remaining fluoride is urgently required around the hydrofluoric acid leak spot. Fertilizing of dolomite containing Ca and Mg, which can trap fluoride, was prepared as one of the restoration plans. In addition, phosphate fertilizing was added in order to enhance soil ameliorating effects. Furthermore, we recommend the introduction of tolerant plants as the second measure to mitigate fluoride damage. As the tolerant plants to make a new forest by replacing trees died due to hydrofluoric acid gas damage, we recommended Q. aliena and S. china, A. hirta, etc. were recommended as plant species to add mantle vegetation to the forest margin to ensure stable interior environment of the forest.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.10-19
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• 2000

Due to the urbanization, concentrated population, and limited land exploitation in the modern society, the environment surrounding that we live in is getting polluted more and more, and it has become hard even to let urban children experience the nature. This research was conducted to help people recognize the importance of our natural resources through the environmental education of elementary school and to use school's practical open-space for the Indigenous Plants education. The results of this study are as follows : First, the status of a plant utilization in our institutional education : There were 362 species totally of 124 species of Trees, 156 species of Herbs, 63 species of Crops, and 19 species of Hydrophytes which appear in the elementary school text book. Of all, the most frequently appearing species of tree were the Malus pumila var. dulcissima, Pinus densijlora, Citrus unshiu, Diospyros kaki. Second, the effect of plant education using the land around schools : The result of research on the open-space of the 19 elementary schools located in Mapo-gu showed that most of the species planted are the Juniperus chinensisrose, Hibiscus syriacus. Pelargonium inquinans in the order of size, and the plants appearing in text book were grown in the botanical garden organized in 7 schools. Especially most of the Indigenous Plants were being planted in botanical garden, and Pinus densijlora, Abeliophyllum distichum, Polygonatum var. plurijlorum, Liriope platyphylla and so on. Last, the result of this research on recognition of Environment, Planting education and Indigenous plants : It showed that educational necessity of students and teachers about environment and Indigenous Plants was more than 80%. The management of botanical garden was conducted by some teachers and managers. The results of this study suggested that we needed the reconstruction of curriculum, the efficient application of plant education for effectiveness of using school environment and monitoring continually and construction information sources for the better environment education in the elementary schools.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.287-296
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• 2002

A field trial was conducted from May to November 2000 at four regions of Jeju province(Jeju, Seogwipo, Susan Seongsan and Keumak Hallim) to estimate adaptation, dry matter yield and nutrient value of kenafs(Everglades 41 and China Choung-pi 3) and a sorghum-sudangrass hybrid(Pioneer 947). Total dry matter(DM) yields of sorghum-sudangrass hybrid Pioneer 947, kenaf Everglades 41 and kenaf China Chong-pi 3 were 7,313, 4,653 and 5,238 kg/ha(P<0.05), respectively, kenaf China Chong-pi 3 being the highest. The region specific dry matter(DM) yields of Jeju, Seogwipo, Seongsan and Hallim area were 5,040, 5,663, 7,283 and 4,950kg/ha, respectively, showing that Seogwipo was the highest. Average DM yields of two kenaf varieties were 4,946, and 3,246 kg/ha for 1st time-cutting and 2nd time-cutting, respectively. The average dry matter(DM) yield of kenaf was significantly higher in the 1st time-cutting than the 2nd time. No significant difference in neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents was found among three varieties. The average crude protein(CP) content of kenaf was higher than that of sorghum-sudangrass hybrid(P<0.05) and was higher in 2nd time-cutting than in 1st time-cutting(P<0.05). There were no significant difference in the heavy metal content of soil either between the sorghum hybrid and kenafs or between two kenaf varieties. In conclusion, the average dry matter(DM) yield of kenaf was lower than that of sorghum hybrid, Contrarily the crude protein(CP) content of kenafs was higher than that of the sorghum hybrid. The average dry matter(DM) yield of kenaf showed higher in 1st time-cutting than 2nd time-cutting, while the crude protein(CP) content of kenafs decreased with time.