• Journal of the Korea Organic Resources Recycling Association
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• 제12권3호
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• pp.95-111
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• 2004

This research sought to determine the status of the installation and operation of composting facilities of domestic public resource-making facilities and come up with corresponding improvement measures. The composting facilities were the most extensively installed of related facilities with over a 0.5 ton treated volume per day. The monthly and yearly carry-in volume of food waste were found to stand at 1,101.7 tons per day and 930.9 tons per day, thus falling short of the average planned volume of 1,270.9 tons. Many composting facilities, which were installed in areas for which factory registration were not approved, did not get approvals. Composting facilities underwent operation stoppage mainly due to faulty fermentation and crushing equipment. Mainly metals contained in food waste caused faults to the crushing equipment, thus requiring a facility designing against faults and corrosion. The initial water content was found to stand at 50-60%, thus complying with the requirement. However, since the composting food waste had an appropriate mixture of sawdust, food waste, and returned compost, it should meet the initial conditions. For fermentation facilities, the duration time for fermentation was 15 days, and post-fermentation tanks required 21 days of duration time, thus establishing the minimum criteria. However, some facilities did not meet the requirements, taking more time in decomposition, thus suggesting a need to determine the duration time according to facilities. In composting food waste, microorganism-based thermal oxidizer-operated fermentation tanks should be used to ensure an economic operation. On the contrary, 14 out of 25 survey targets heated fermentation tanks in any form. These thermal facilities contain the growth of bacteria, lowering chemical reaction in composting; thus composting facilities should be basically designed to use microorganism-based thermal oxidizers in drying water. An average daily volume of food waste and supplementary materials that was injected in producing compost was 22.8 tons. This volume produced 7.3 tons of compost per day, decreasing 68%. Properties of produced compost were analyzed by its color, absence or presence of remaining decomposition heat, and smell, to assess the quality. As a result, the composting process was not properly installed nor operated in about 50% of composting facilities. Compost should be produced to be soil-friendly.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제54권3호
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• pp.260-264
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• 2009

Sufficient seedling establishment of Chinese milk vetch (CMV) is the most important factor in the CMV cultivation. In order to obtain sufficient seedling stand, CMV seed should be planted at right seed planting date. An optimum CMV seed planting time for stable seedling establishment was determined based on the final water drainage time for rice harvest in fall. Five planting times from 10 days before water drainage (DBWD) to 15 days after water drainage (DAWD) at five day interval were evaluated during the period of 2006-2007 and 2007-2008 and the optimum CMV seed planting time was determined based on seedling stand, winter survival rate, and dry matter production. CMV seedling stand before winter was high with $575{\sim}1,050\;plants/m^2$ regardless of seed planting times but after overwintering, it was greater in seed planting date between 5 DBWD to 5 DAWD than that of 10 to 15 DAWD treatments. Winter survival rate, dry matter production and seed production yield also showed similar trend to the seedling establishment. On the other hand, when CMV seeds were sowed early at 10 DBWD, seedling stand and winter survival rate were lower than that of 5 DBWD to 5 DAWD. This result indicates that an optimum CMV seed planting time based on the final water drainage could be between 5 DBWD (September 20) to 5 DAWD (September 30).

• Horticultural Science & Technology
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• 제33권4호
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• pp.511-517
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• 2015

This research was conducted to evaluate the influence of root restriction materials and media on the growth of runner plantlets of 'Seolhyang' strawberry in a nursery field. To achieve this, the influence of three kinds of root media on the growth of runner plantlets was monitored when polyethylene film was used as the root restriction material. In addition, the influence of various root restriction materials (RRS) such as transparent polyethylene film (PE), non-woven fabric (NF), perforated polyethylene film (PP), and root proofing sheet (RPS) on the changes in volumetric water content (VWC) and temperature of root media as well as growth of runner plantlet were investigated when expanded rice hull (ERH) was used as the root medium. In the comparison of root media, growth parameters such as leaf area and crown thickness at 20 d after fixation as well as crown thickness and fresh weights of root and above-ground tissue at 40 d after runner plantlet fixation were higher in the ERH treatment than in sandy loam and loamy sand. When the influence of RRS was compared, the VWC of ERH was 55% just after irrigation, but decreased to 26% at just before irrigation. Ranges of the VWC as influenced by irrigation cycle were 16 to 10% in the PP and less than 10% in the NF and RPS. The soil temperature in the PE treatment was around $1^{\circ}C$ lower than in NF, PP, and RPS. The differences between day and night temperatures were also smaller in the PE treatment rather than those in NF, PP, and RPS. The growths of runner plantlet 50 d after fixation showed that plant heights as well as fresh weights of root and above-ground tissue were higher in the PE treatment than in NF, PP, and RPS. NF and PP did not effectively restrict roots inside the medium and the roots of runner plantlets penetrated through the root restriction materials resulting in the formation of root system below the restriction materials. The above results indicate that ERH is more effective than sandy loam or loamy sand as root medium. PE rather than NF, PP, or RPS as root restriction material resulted in better growth of runner plantlets in propagation of 'Seolhyang' strawberry. The results of this research will be used for production of high quality runner plantlets in strawberry propagation.

• Journal of Korean Society of Forest Science
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• 제98권6호
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• pp.733-739
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• 2009

This study was carried out to analyze the relationship between major climatic factors (monthly temperature, precipitation) and radial growth of Korean Pine (Pinus koraiensis) in Inje-gun(Mt. Seorak), Sanchung-gun and Namwon-si(Mt. Jiri). Radial growth measurements were crossdated and correlated with climate variables. The climatic factors used were monthly mean temperature and monthly precipitation from August of previous year to September of the current year. In Inje-gun, radial growth was negatively correlated with monthly mean temperature in April, May, June, and August of the current year and was positively correlated with precipitation in August, October of the previous year and in April, August of the current year. Sanchung-gun showed a negative correlation with monthly mean temperature in September of the previous year and August of the current year but positive correlation in January of the current year. In contrast, precipitation in September of the previous year and August of the current year showed a positive influence. The results suggest that high temperature together with low precipitation may thus cause water stress and thereby limit radial growth in this region. In Namwon-si, the climategrowth relationships show that radial growth was negatively correlated with monthly mean temperature in August, October of the previous year and June of the current year. But August of the previous year and May, August of the current year in precipitation was positively correlated with radial growth. In the study areas, precipitation plays an important role for the radial growth of Kroean Pine (Pinus koraiensis). The results suggest that precipitation is important in the radial growth because water deficit in trees would take place in response to high temperature in the study area. Also there was some differences with study areas in the effects of both climatic variables probably as a result of different stand structure and geographical conditions and micro-climate.

• Journal of Animal Environmental Science
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• 제13권1호
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• pp.13-20
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• 2007

Sawdust biofiltration is an emerging bio-technology for control of ammonia emissions including compost odors from composting of biological wastes. Although sawdust is widely used as a medium for bulking agent in composting system and for microbial attachment in biofiltration systems, the performance of agitated bed composting and sawdust biofiltration are not well established. A pilot-scale composting of hog manure amended with sawdust and sawdust biofiltration systems for practical operation were investigated using aerated and agitated rectangular reactor with compost turner and sawdust biofilter operated under controlled conditions, each with a working capacity of approximately $40m^3\;and\;4.5m^3$ respectively. These were used to investigate the effect of compost temperature, seed germination rate and the C/N ratio of the compost on ammonia emissions, compost maturity and sawdust biofiltration performance. Temperature profiles showed that the material in three runs had been reached to temperature of 55 to $65^{\circ}C$ and above. The ammonia concentration in the exhaust gas of the sawdust biofilter media was below the maximum average value as 45 ppm. Seed germination rate levels of final compost was maintained from 70 to 93% and EC values of the finished compost varied between 2.8 and 4.8 ds/m, providing adequate conditions for plant growth.

• Journal of Korean Society of Forest Science
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• 제38권1호
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• pp.27-32
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• 1978

The diurnal pattern of leaf water potential in cuttings by Dye Method was as follows: 1. Diurnal pattern of leaf water potential (${\psi}_l$) in Viburnum Awabuki K. Koch and Daphne odora Thunb. was shown the pattern of the curves without mutual relation with soil classes when soil water potential (${\psi}_s$) was 0 bar. When ${\psi}_s$ was above -0.01 bar, the cuttings in the loamy sand (L.S.) was shown by the maximum values than that in sandy clay (S.C.) by about -1 bar gap (Fig. 1). 2. The diurnal changes of ${\psi}_l$ was shown the most high from two to eight O'clock in the morning, the maximum value was -3 bars when ${\psi}_s$ was above -0.01 to -0.02 bar, and was -4 bars below -0.03 bar. The diurnal the lowest values of ${\psi}_l$ showed -20 to -22 bars from one to two O'clock in the afternoon. In the fifteenth day after cutting V.A., the staying time in the diurnal maximum values of ${\psi}_l$ is about half in comparison with it in the fifth day. The curves of recovery of water stress (Fig. 1), the former reached to the diurnal maximum values -1 to -2 bars lately every hours comparing with it of the latter. The general diurnal pattern of ${\psi}_l$ was most clearly related to change with air temperature and the relative humitidy. 3. Comparing the treatment block by IAA 50 ppm with controlled block in fifteenth day after V.A. cuttings, in case of treatment reached to maximum values -2 to -3 bars lately as shown Fig. 2., and also staying times was only half in comparison with controlled block. 4. The cuttings 4 leafs was much rootings than 2 leafs in V.A. (Table. 1), and the former reached maximum value -2 to -3 bars lately every hours comparing with the latter. 5. In case of Buxus microphylla var. Koreana as shown Fig. 3., comparing the pattern curves of in the cuttings 8 leafs with 4 leafs, the former reached to maximum values -2 to -3 bars lately in comparison with the latter, but reffering to the amount of rooting (Table. 2), the former is less than the latter.

• Korean Journal of Plant Resources
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• 제25권1호
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Korean Journal of Weed Science
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• 제14권2호
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• pp.120-127
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• 1994

To establish an efficient herbicide screening method for purple nutsedge(Cyperus rotundus) control, its sprouting characteristics, tuber production and responses on several herbicides were investigated under greenhouse condition. The tubers stored at $4^{\circ}C$ after sterilization with the diluted prochloraz(Spotac) solution showed higher sprouting than the non-sterilized did. The harvested tubers were not dormant, and the sterilized tubers which stored at low temperature had a sprouting capability of about 80% after 6 months. If the fresh weight of purple nutsedge tubers was decreased to below 48%, they could not sprout. However, the tubers soaked in water and then stored at low temperature could sprout by 88% even 6 months later. Sprouting and initial growth of tuber were much better at $35^{\circ}C$-day/$25^{\circ}C$-night than at 30/$20^{\circ}C$ or 25/$15^{\circ}C$. The half-sected tubers, which were prepared by setting the intact tuber of above 1.2g latitudinally, were shown similar initial growth to the intact but those sected crucifically were not. These results suggest that the half-sected tuber itself can be used as a material on herbicide screening. About 1000 tubers could be harvested when 10 tubers planted in a pot($56{\times}35{\times}16cm$) filled with the artificial soil were cultivated in greenhouse of $35^{\circ}C$-day/$25^{\circ}C$-night for 3 months(April-July, 1993). Chlorimuron, Bentazon and Norflurazon were selected as the standards for the screening because of providing relatively effective control on purple nutsedge in both soil-surface and foliar spray treatment.

• Korean Journal of Plant Tissue Culture
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• 제25권4호
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• pp.257-261
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• 1998

The repeated subcultures of in vitro plant materials in wasabi became highly vitrified and the capacity for multiple shoot formation from the vitrified plant materials was very low. In order to improve the quality of in vitro propagated planting materials, the experiments were carried out using culture vessels capped with membrane filter(MF). When vitrified shoots were cultured on MS medium with 0.2mg/L BA in the vessels with MF or without MF for 60 days, the shoots in the vessels with MF did not vitrified. In contrast, the shoots grown in the vessels without MF vitrified at 65%. The stomates of vitrified leaves were circular and inflated, whereas those of normal leaves acclimatizated in the vessels with MF were ovate in shape. The hardened shoots were also cultured on MS media without sucrose containing 0.01mg/L IBA in vessels with(photoautotrophic culture) or without(control) MF. Sucrose was necessary for survival of the in vitro plantlets in the vessels without MF. After 20 days of culture, the shoots in the vessels without MF on the sucrose-free media turned yellow and died. But the shoots in the vessels with MF in the sucrose-free media produced a lot of roots. When shoots were cultured on MS medium with 2% sucrose containing 0.01mg/L IBA in the vessels with(photomixotrophic culture) or without(heterotrophic culture) MF, best growth occured in photomixotrophic culture.

• Asian Journal of Turfgrass Science
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• 제23권2호
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• pp.331-344
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• 2009

Buffalograss is an important turfgrass species with excellent cold, heat, and drought tolerance. Understanding the physiological integration of buffalograss under heterogeneous conditions helps to develop cultural practices that better use limited resources for uniform turf quality. The objective of this study was to evaluate physiological integration of buffalograss under water deficit stress and the involvement of lipid peroxidation and antioxidants in the process. In one experiment, buffalograss was planted in the center of a four-compartment growth unit. Watering frequencies, once a week(+) and once in two weeks(-), were combined with the sand(S) or peat(P) in each unit to generate five total treatments(P+S-P-S+, P+P+P+P+, S-S-S-S-, P-P-P-P-, and S+S+S+S+). The average number of shoot established from the heterogeneous root-zone medium was higher than the average of four possible homogeneous media. In second experiment, single ramet in Hoagland solution($S_0$) or single ramet in Hoagland solution with 20% PEG-6000($S_s$) were compared with two connectedramets under different treatments. Treatments for connected ramets were young ramet in Hoagland solution($Y_{os}$) and old ramet in Hoagland solution with 20% PEG-6000($O_{os}$), and old ramet in Hoagland solution($O_{ys}$) and young ramet in Hoagland solution with 20% PEG-6000($Y_{ys}$). Lipid peroxidation, antioxidants, and proline showedphysiological integration between ramets subjected to different levels of water stress. Superoxide dismutase(SOD), Guaiacol peroxidase(G-POD), malondialdehyde(MDA), and free proline also showed different time courses and relative activities during the physiological integration.