• Korean Journal of Weed Science
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• v.1 no.1
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• pp.44-51
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• 1981

An experiment was conducted to obtain the basic information about competitive ability of rice against weeds as affected by culm length at the Yeongnam Crop Experiment Station, Office of Rural Development in 1980. More weeds were harvested from the plot of short statured cultivar, Manseogbyeo compared to the plot of Cheongcheongbyeo that was approximately 10cm taller than Manseogbyeo regardless of planting density variables. Weeds also decreased as rice population increased from $30{\times}15cm$, $40{\times}(10{\times}10cm)$ and to $10{\times}10cm$, in order. The degree of weed suppression and floristic composition was varied depending upon plant spacing and weeding regime subjected at the previous year. The degree of weed suppression became increased with increasing rice population. The degree of weed suppression at the $10{\times}10cm$ plant spacing showed as high as hand weeding subjected in the previous year. However, in terms of floristic composition, Scirpus hotarui Roxb. became dominant when rice had cultivated at $10{\times}10cm$ plant spacing in the previous year while S. hotarui and Sagittaria pygmaea Miq. were both important in the hand weeding plot. The highest grain yield of rice showed at the $10{\times}10cm$ plant spacing while no significant difference was observed between $40{\times}(10{\times}10cm)$ and $30{\times}15cm$ plant spacings for both weeding regimes and both cultivars. However, response of grain yield to weeding regime was differed in two cultivars. For Manseobgyeo, significant grain yield decreased in no weeding plot regardless of plant spacing variables. But in case of Cheongcheongbyeo, grain yield reduction was only recognized at the $30{\times}15cm$ plant spacing. Based on these result it could be concluded that Cheongcheongbyeo (10cm taller in height) seemed to be more competitive against weeds than Manseogbyeo.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.305-311
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• 2012

To investigate the influence electrical conductivity (EC) of nutrient solution and light intensity on growth of red leafy lettuce, fresh and dry weights, number of leave, chlorophyll concentration and production efficiency were evaluated through nutrient film technique system. The levels of EC were 0.5, 1.0, 1.5, 2.0, 3.0, and $6.0dS{\cdot}m^{-1}$, and those of light intensity were 120, 150, and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Under photoperiod of 16 h/day, the temperature was maintained in the range of $20{\sim}25^{\circ}C$. Planting density was $10{\times}10cm$ (100 plants/$m^2$). When red leafy lettuce were grown in the EC range of $0.5{\sim}1.5dS{\cdot}m^{-1}$, the fresh and dry weights decreased as the EC levels and light intensity were lowered, however, Hunter's a value showed no significant differences among the treatments of EC and light intensity levels (Ex. 1). The fresh and dry weights and production efficiency ($g{\cdot}FW/kw$) were the highest in the treatment of $3.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ when crops were grown under the EC range of EC $1.5{\sim}6.0dS{\cdot}m^{-1}$ (Ex. 2). But the fresh and dry weights, number of leaves, and production efficiency of $2.0dS{\cdot}m^{-1}$ were the highest when the light intensity was $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ (Ex. 3). The SPAD value increased gradually as EC levels were elevated. From the above results, we concluded that optimum levels of EC and light intensity were $2.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively, for production as well as production efficiency of red leaf lettuce in plant factory.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.88-99
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• 2018

After UNESCO appointed Royal Tombs of the Joseon Dynasty to be World Cultural Heritages(2009), Cultural Heritage Administration in Korea established Management Office of Royal Tombs of the Joseon Dynasty(2012) and conducted Mid to Long-Term Plan on Conservation, Management, Utilization of World Heritage 'Royal Tombs of the Joseon Dynasty(2015)'. The report, as an implementation plan, provides detailed contents of the maintenance planning of Royal Tombs of the Joseon Dynasty. From this background, with a view to comprehending the characteristics of the maintenance planning of trees in historical landscape forests, this study extracted the contents related to the historical landscape forests of the 40 Royal Tombs of the Joseon Dynasty from the "Mid to Long-term Plan" and conducted literature research. The results of the study are as follows. First, from 2016, the short-term plans have provided detailed contents on logging, transplanting and planting trees in the plans divided by stages. On the other hand, the long-term plans, instead of presenting abstract contents repeatedly for each royal tomb, should seek vegetation landscape that each royal tomb should aim for. Second, since the areas that are in charge of the various functions of the royal tombs have been subjects to the maintenance planning, it is effective to establish a maintenance planning by separating functional areas instead of the comprehensive concept as historical landscape forests. Third, the maintenance planning of trees in historical landscape forest of the Royal Tombs of Joseon Dynasty is based on daily management such as density control and maintaining the shape of trees, which is necessary to sustain the forest. Also, due to the goal of preserving the pine forest, which is recognized as a prototype vegetation landscape, foreign species and other trees have been more cut down. With a few limited types of tall tree but few shrubs and flowers, it is characterized that the orientation toward aesthetic landscapes is insufficient in large green spaces. Fourth, according to the function of the tomb, it is divided into entrance area, ceremonial area, burial area and outer forest, and the contents of the maintenance planning are analyzed by basic conditions of tree management: prototype, ecology, functionality, and aesthetics. After studying the tree management characteristics of each area, four suggestions are made: understanding the diversity of trees that form prototype landscape as a management plan, sustainability of various forests adapted to ecological environment, convenience required in addition to ceremony and safety characterizing the Royal Tombs of Joseon Dynasty, and the necessity of access to aesthetic landscape on the tombs.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.108-113
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• 1984

To find out the differences in micro-meteorological changes in the rice plant canopy at the different growing stages, Seokwang-byo, a high yielding variety, was cultivated with three planting densities of 50, 80 and 110 hills per $3.3m^2$ in 1982, and Seokwangbyo and Chucheong-byo, a local variety, were planted with a density of 80 hills per $3.3m^2$. Air temperature in plant canopies, water and soil temperatures were continuously monitored throughout the growing period. The relationship between solar radiation interception and leaf area indices at different height in the canopy also was studied. The results were as follows: 1. Air temperature in the densely planted canopy was 1 to $1.5^{\circ}C$ higher than that in the sparsely planted one at the early growing stage, but was inverted after 60 days of transplanting. The vertical distribution of temperature in the canopies showed that air temperature at 10 cm height from the ground was higher than that at 30 cm height. The temperature inversion occurred showing lower temperature at the 10 cm height than at the 30 cm height. 2. The highest temperature of a day in the canopy occurred at 14:00 to 15:00 Korean Standard Time same as that of air temperature, but approached to the solar noon time as the plants grew thick. 3. The air temperature in the canopy became higher than water temperature when the leaf area indices were 4.6 for Chucheongbyo and 5.2 for Seokwangbyo, and the light penetration ratios were 40 percents. 4. Light extinction coefficients of the 50 to 70 cm layer of the canopies were 0.3 to 0.5 but decreased at the lower layers. 5. Albedo of the canopies was 0.4 in the morning and evening while that was about 0.25 at noon. The difference in albedo between Seokwangbyo and Chucheongbyo could be recognized with the difference in leaf structure.

• Journal of Life Science
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• v.17 no.12
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• pp.1701-1708
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• 2007

Seed pelleting is generally conducted in order to save the labor for sowing and thinning by enabling the precision mechanical planting. In the present study, the influence of physical and chemical properties of pelleting solid materials was investigated on carrot seed germination. Among the pelleting solid materials evaluated, dialite, kaolin, and talc showed low bulk density and high porosity. Bentonite and dialite carried high water holding capacities of 184% and 173%, respectively, while calcium carbonate, calcium oxide, and fly ash showed relatively low water holding capacity. The pH of kaolin (6.8) and dialite (7.4) were close to neutral, while limestone (12.8), calcium oxide (13.0), and bentonite (10.0) were highly basic. High electro-conductivity was shown in limestone and calcium oxide. EDS analysis revealed that the main elemental compositions of talc were Si (71.0%) and Mg (29.0%), and those of calcium carbonate were Ca (66.6%), Si (22.9%), and Mg (10.5%). High granulation capacity was observed from talc and the mixture of talc and calcium carbonate. Seeds pelleted with bentonite showed the highest hardness. The dissolving type of the pellet layer after imbibition was split type in talc, limestone, zeolite, and fly ash, melt type in calcium carbonate and calcium oxide, and swell type in bentonite and vermiculite. The shortest dissolving time of pellet layer was observed from calcium carbonate and kaolin. The germination speed $(T_{50})$ was delayed as the size of pelleted seeds increased. The optimum size of pelleting was 19 ratio in carrot.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.1
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• pp.28-37
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• 2011

In this study, the series-poem, Bihaedangsasippalyoung(48 poems for beautiful scene of Bihaedang), written by scholars of Jiphyonjeon for Bihaedang garden of Anpyung-Daegun(Prince Anpyung, 1416-1453), was analyzed focusing on scenery lexeme to interpret the meaning of scenery and gardening culture of Sadaebu(noblemen) during the first term of Chosun Dynasty. The study result is as followings. First, the subtitle of Sasippalyoung(48 poems) written by Anpyung-Daegun while he grew Bihaedang garden on the foot of Inwang Mountain showed repetitive nomativity comparing joining of yin and yang, such as life and form of animal and plan, time and space, meaning and symbolism, etc. Among scenery lexemes, 38 are represented plant and flowers, and 8 are represented gardening ornaments and animals. Second, the names of gardens were expressed as Wonrim, Jongje, Imchon(Trees and Ponds), or Hwawon(Flower garden), or also presented as Gongjeong(Empty garden), Manwon(Full garden), Jungjeong(Middle garden), Huwon(Backyard), Wonrak(Inner court), or Byulwon(Seperated garden) depending on density and location. In addition, there were pavilions and ponds, stepping stones and stairs, a pergola, a flat bench, flowerpots, an artificial hill, oddly shaped stones, wells, aviary, flower beds, or hedges. A gardener was called Sahwa(flower keeper), planting and gardening of garden trees were called Jaebae(cultivation), a pond island was called Boogoo(floating hill), and miniature landscapes were called Chukjee(reduced land). Third, willows were planted on the outdoor yard, and plum trees were planted in front of the library, which led to bamboo woods road. Peony, camellia, tree peony and crepe myrtle were planted on the inner court with mossy rocks, small artificial hills, glass rocks, flower pots. There were rectangular ponds, while breeding deer, dove, rooster, and cranes. Fourth, landscape elements were enjoyed as metaphysical symbolic landscape by anthropomorphism, such as (1) gentlemen and loyalty, (2) wealth and prosperity, (3) Taoist hermit and poetical life, (4) reclusion and seclusion, (5) filial piety, virtue, introspection, etc. In other words, the garden presented a variety of gardening culture appreciating meaningful landscape, such as investigation of things, reclusion and seclusion, and building orientation of a fairyland yearning eternal youth and Mureungdowon(Taoist Arcadia) by making a garden blending beautiful flowers and trees, with precious birds and animals. Fifth, there were many landscape appreciation schemes, such as Angkyung(looking-up), Bukyung(looking-down), Jeokyung(looking-under), Chakyung(bringing outer space into inside), Yookyung(flower viewing), Yojeong(walking around the garden enjoying flowers), Hwasaekhyangbyuk(flower gardening), and Garden appreciation enjoying landscape through time and seasons with different inspirations.

• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.303-314
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• 1988

Tong-ri beach has not enough vegetation to be enjoyed by the sea bathers and to be satisfied with preventing the disaster-damages, but mixed forest near the beach can work its funtions and the old forest of Pirus thunbergii $P_{ARL}$. near the beach do a Little. Therefore it is very urgent to plant more trees near the beach for bathers and disaster-damage prevention. This study was carried out for planning an afforestation, with reporting upon the crown amounts and soil properties of disaster-damage prevention forests of P. thunbergii $P_{ARL}$. planted on the coast sand dunes in 1970 and 1976, and with reporting upon the valuation on soil properties of the lands near the beach in order to set the afforestation site. The results are as follows : 1. In disaster-damage prevention forests, crown surface area and crown volume became increasingly greater in proportion to the height. To D.B.H., crown volume also became increasingly greater in proportion, but crown surface area was directly proportional. 2. In comparison to sail characteristics of sand dune, those of the forests were in large quantity in OM, T-N and avail. $SiO_2$, and almost in the same in avail. $P_2O_5$, but in small quantity in exchangeable canons : K, Ca, Mg and Na. 3. EC, Cl and pH were in small value in the forest soils, but CEC was in large value in those soils. 4. Above facts showed that the forests fulfill their functions for preventing disaster-damages and improve their soil properties. 5. The forests have naturally been thinned up to 34% in 17 years and 39% in 11 years, and one can easily pass through the forest(planted in 1970), because of its sufficient clear-length(2.71m) and its space to pass. 6. A plan for afforestation was oracle nut after judging several sites by the evaluation on the soil properties and considering the best relaxation and the prevention of the various disaster-damages upon which were reported in the last issue. 7. Afforestation should be kept for maintaining its appropriate density for best relaxation and disaster-damage prevention.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.60-73
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• 1989

Two field experiments were carried out to assess the applicability of a central composite design (CCD) in determining optimum culture condition of an early rice cultivar, Unbongbyeo in southern Korea. A central composite design with two replicates was applied to five levels of five factors such as the number of hills per 3.3m2, the number of seedlings per hill, the levels of nitrogen, the transplanting date and the seedling age (Experiment 1). The levels of planting density were ranged from 30 hills to 150 hills per 3.3m2 ; the number of seedlings per hill from 1 seedling to 9 seedlings per hill; the levels of nitrogen application from 1 kg/l0a to 21 kg/l0a; the transplanting date from June 15 to July 5; the seedling age from 25 days to 45 days. A fractional factorial design was applied to three levels of five factors tested in CCD (Experiment 2). Yield per hill and per unit area were examined and the results obtained from both experiments were compared. The benefits from the central composite design were discussed. Maximum yield of brown rice per unit area was obtained at the combination of the central levels of one of five factors when the other four factors were fixed at central point. Furthermore, brown rice yield per unit area affected by interaction of two factors was maximized at the central point when the remain three factors being fixed at the central level. The responses of five factors to brown rice yield per hill and unit area were found to be a saddle point in both designs. Actual values of the stationary points were 107 hills per 3.3 m2, 4 seedlings per hill, 10 kg nitrogen per l0a, transplanting date of rice on June 26 and 33 days of seedling age in the central composite design. Brown rice yield per unit area at the stationary points were estimated 439 kg/l0a in the central composite design and 442 kg/l0a in the fractional factorial design. Considering the number of experimental treatment combinations, the central composite design was rather convenient in reducing the number of treatment combinations for similar information. It was more convenient for an experimenter to present the results from the central composite design than those from the fractional factorial design. Considering the optimum yields of brown rice per unit area at the stationary points being verified as saddle points in both designs. inter-heterogeneity of each of the factors should be avoided in setting up factors in pursuit of inducing unidirectional response of the factors to yield. Even though both the lower and higher levels in the central composite design being beyond the region of an experimenter's interest. they were considered highly valued in interpretation of the results. Conclusively. the central composite design was found to be more beneficial to optimize culture condition of paddy rice even with several levels of various factors were involved.