• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.279-283
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• 2004

This experiment was carried out at paddy field (commercial silty loam soil) in the southwestern Korea. Pungsannamulkong, a determinate growth habit, was a relatively high yielding and late maturing cultivar, and Han­namkong, a semi determinate growth habit, was a relatively low yielding and early maturing cultivar. Seeds were sowed at two plants and with a planting density of $70{\times}10cm$ on May 26, 2003. Fertilizer was applied prior to planting at a rate of 3.0-3.0-3.4g $(N-P_2O_5-K_2O)\;per\;m^2$ by all basal fertilizations. Experimental design was a randomized complete block with three replications. Seed yield was higher in Pungsannamulkong by 362g per $m^2$ than in Hannamkong of 260g per $m^2$ Also, the number of pod, number of seed, and number of seed per pod were greater in Pungsannamulkong than in Hannamkong. The number of leaves per $m^2$ showed similar with two soybean cultivars up to August 24 but thereafter it decreased in Hannamkong. The leaf area up to August 4 increased in Hannamkong higher than in Pungsannamulkong, but after that time, Pungsannamulkong had greater leaf area than Hannamkong. The shoot and leaf dry matter of two soybean cultivars from June 23 to August 4 were similar but thereafter, Pungsannamulkong had a significantly greater than Hannamkong. Crop growth rate (CGR), relative growth rate (RGR) and net assimilate rate (NAR) for Punsannamulkong were relatively higher than Hannamkong but leaf area ratio (LAR) and specific leaf weight (SLW) showed higher in Hannamkong. Most of leaves distributed in the ranges of 80-90cm and 60-70cm from the soil surface in Punsannamulkong and Hannamkong, respectively. Pods of Punsannamulkong ranged 10-80cm from the soil surface and most of pods were distributed at 40-50cm. Photosynthetic rate at the flowering stage showed a significant difference between cultivars in the upper most leaf position. There was no significant difference of the photosynthetic rate at $7^{tn}$ leaf at the flowering stage, and the uppermost and 7th leaf position at the seed development stage between two soybean cultivars.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.508-515
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• 2015

Post-fire restoration can affect breeding bird communities and species compositions over a long-term period by determining pot-fire succession, and a long-term monitoring is therefore required to understand its impacts on forest birds. This study aimed to document the effects of post-fire restoration methods on breeding bird communities in three areas: unburned and two burned (nonintervention and intervention with clear-cut logging and planting) stands 13 years after the stand-replacing Samcheok forest fire at Mt. Geombong in Samcheok, South Korea. According to 108 point counts during the breeding season from April to June 2013, we found that the number of individuals, observed bird species, and species diversity index in intervention stands with clear-cut logging and planting were lower than that in nonintervention and unburned control stands. Foraging and nesting guild analysis also showed a lower abundance of foliage searchers, timber drillers, primary cavity nesters and secondary cavity nesters in intervention stands than in the other stands, while no significant difference was detected between the nonintervention and unburned stands. These results imply that an interventional restoration method may deter the recovery of avian breeding communities after forest fires, and also suggest that non-interventional restoration methods may be an effective way to benefit the species diversity and density of breeding bird communities.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.3
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• pp.18-32
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• 2024

This study aims to analyze the summer human thermal environment in Jeju City's outdoor parking lots by measuring microclimate data and comparing pavement and vegetation albedoes and elements through computer simulations. In measured cases, results due to albedo showed no significance, but there was a significant difference between sunny and shaded areas by trees. The sunny area had a PET (physiological equivalent temperature) in the 'very hot' level, while the shaded area exhibited a 2-step lower 'warm' level. UTCI (universal thermal climate index) also showed that the sunny area was in the 'very strong heat stress' level, whereas the shaded area was 1-step lower in the 'strong heat stress' level, confirming the role of trees in reducing incoming solar radiant energy. Simulation results, using the measured albedoes, closely resembled the measured results. Regarding vegetation, scenarios with a wide canopy, high leaf density, and narrow planting spacing were effective in mitigating the human thermal environment, and the differences due to tree height varied across scenarios. The scenario with the lowest PET value was H9W9L3D8 (tree height 9m, canopy width 9m, leaf area index 3.0, planting spacing 8m), indicating a 0.7-step decrease compared to the current landscaping scenario. Thus, it was confirmed that, among landscaping elements, trees have a significant impact on the summer human thermal environment compared to ground pavement.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.407-411
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• 2008

This study was conducted to estimate the economic injury level (EIL) and economic threshold (ET) of the green peach aphid, Myzus persicae, on Chinese cabbage (Brassica campestris var). The changes of biomass of Chinese cabbage and M. persicae density were investigated after introduction of M. persicae at different density (0, 2, 5, 10, 15, and 20 per plant; inoculated at 10d after planting). The densities of M. persicae largely increased from the above initial densities to 0, 92.3, 177.4, 406.9, 440.4, and 471.3 aphids per plant at 18d after the initial inoculation, respectively. The biomass of Chinese cabbage significantly decreased with increasing the initial inoculated density of M. persicae: 602.0, 264.2, 262.0, 109.3, 151.0, and 67.3 g in above plots with different initial densities, respectively. The relationship between cumulative aphid days (CAD) and yield loss (%) of Chinese cabbage was well described by a nonlinear logistic equation. Using the estimated equation, EIL of M. persicae on Chinese cabbage was estimated 25 CAD per plant based on the yield loss 13%, which take into account of an empirical gain threshold 5% and marketable rate 92% of spring Chinese cabbage. Also, ET was calculated at 80% of EIL: 20 aphids per plant. Until a more elaborate EIL-model is developed, the present result may be useful for M. persicae management at early growth stage of Chinese cabbage.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.39-49
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• 2017

The present study conducted a comparison on tree growth and productivity of high-density apple orchards by several orchard management systems: making scaffolds by heading-back and thinning out pruning (T-1), maintaining scaffolds upward and bearing shoots downward (T-2), managing branches slightly upward without heading-back (T-3), keeping leaders downward and shoots pending (T-4), maintaining leaders high and branches horizontal with severe pinching (T-5), making leaders with lower branches vigorous and upper shoots pending (T-6), and controlling very high planting density with bending branches (T-7). In conclusion, the orchards of (T-5) and (T-6) management systems showed a superior performance in controlling tree growth, productivity, and quality of fruits. Also, superior management efficiency was obtained in the orchards of (T-5) and (T-6).

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.545-555
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• 1994

The objective of the study was to provide the useful scientific data on the early rehabilitation of the legging road after timber harvesting in the forest area. This study was carried out at logging roads which were constructed during 1989 and 1994 in Mt. Baekwoon. The field survey was conducted in July, 1991. Judging from the analysis of soil bulk density, time required for recovery as the undisturbed forest soil condition was more than 10 years in the road which was left, and the regression equation is as follows, $$Y_1=1.4195-0.0744{\cdot}X(R^2=0.91)$$ $$Y_2=1.4673-0.0688{\cdot}X(R^2=0.73)$$ (X : elapsed year after road construction. $Y_1$, $Y_2$ : soil bulk density($g/cm^3$) at 0~7.5cm, and 7.5~15.0cm, respectively) Especially soil bulk density with buffer strip-woods was $0.890-0.903g/cm^3$, so it was 20% lower than that of logging road surface without buffer strip-woods. Among the 7 factors, location, sand content, and soil hardness had statistically significant effect on the soil bulk density in logging road surface. The pioneer species on logging road surface were Rhus cratargifolius, Prunus chinensis, and Lespedeza cyrtobotrya, etc. in woody species, and Pteridium aquilinum, Arundinella hirta, and Lysimachia clethroides, etc. in herb species. So, in process of year, average plant coverage were 70% on cutting and banking slope and 20% on logging road surface which elapsed 6 years after logging road construction. Through this research, buffer strip-woods must be remained for environmental conservation of forest conditions, and from the time to be closed the road, planting, seeding, and grazing works could be effective to the soil condition and vegetation recovery.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.285-290
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• 1996

This experiment was conducted to investigate the variation of adhering primary and secondary rachis branches of panicle in three ecotypes at National Honam Agricultural Experiment Station in 1993. Three ecotypes. Odaebyeo and Sinunbongbyeo as early-maturing type, Cheongmyeongbyeo and Changanbyeo as medium, and Dongjinbyeo and Mangeumbyeo as late-maturing type were used. The treatment were 5 planting times from May 5 to 5 July by 15 day intervals. The number of primary rachis branch in early maturing type recorded high in between May 5 and 20 May as early transplanting. Medium and late-maturing type, however, was found to be have more primary rachis branches at the late time of June 20 transplanting than at the optimum transplanting of Honam area. The number of secondary rachis branch was high between June 5 and 20 June regardless ecotypes. The rate of secondary rachis branch per primary rachis branch was increased with later transplanting time up to June 5, but showed no differences onwards. The number of grain in primary and secondary rachis branches were low in transplanting time of May 5 regardless ecotype but high in late transplanting time by July 5. Densinty of seed sets was found to be higher in late transplanting than in early transplating;early-maturing type showed high in July 5 and 20 June in medium-late maturing type respectively.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.115-123
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• 2005

Historical changes of population abundances of European red mite (ERM), Panonychus ulmi (Koch), and two-spotted spider mite (TSSM), Tetranychus urticae (Koch) (Acari: Tetranychidae), were described in selected apple orchards in the National Horticultural Research Institute (NHRI, Suwon, Korea), based on research reports of the NHRI from 1958 to 1998. ERM was an abundant species up to 1970, and TSSM became a dominant species after 1980. The change occurred around mid 1970. Three hypotheses were made to explain the change: TSSM competitively replaces ERM, ground cover weeds are a major influencing factor on movement of TSSM (TSSM movement into trees is accelerated by destroying weeds), and ERM and TSSM populations are regulated by natural enemy complexes when the orchard system is not disrupted. And long-term results of the interaction between two species were projected according to the combination of different orchard management strategies: pesticide sprays (non-selective toxic pesticide spray : heavy pesticide pressure (HPP), and selective soft pesticide spray = low pesticide pressure (LPP)) and weed control methods (grass planting, and clean culture system with herbicides). In the HPP and grass planting system, ERMs are abundant because ERM can avoid competition with TSSM as movement of TSSM to trees are restricted, and natural enemy complexes are destroyed by toxic pesticides. In the HPP and clean culture system, TSSMs are abundant because TSSM moves to trees from early season and competitively replaces ERM. In the LPP and grass planting system, ERMs are abundant because movement of TSSM to trees is reduced, but they do not build up a high population density since their densities are regulated by natural enemy complexes. In the LPP and clean culture system, TSSM moves to trees and competes with ERM, but the competition pressure is reduced because population densities of mites are regulated in a lower level by natural enemy complexes. So, ERM can occurs in late season. Thus, two species can coexist temporarily with more ERM in early season and more TSSM in late season. TSSM abundant phenomenon presented in this study can be partially explained as a result of long-term interaction between ERM and TSSM under the HPP and clean culture system.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.349-355
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• 2018

This study was aimed at predicting the yield of paprika (Capsicum annuum L.) through analyzing the growth characteristics, yield pattern and greenhouse environment. In the greenhouse of the Gyeongnam area (667 m above sea level), the red paprika 'Cupra' and the yellow paprika 'Fiesta' were grown from July 5, 2016 to July 15, 2017. The planting density was $3.66plants/m^2$ and attracted 2 stems. During the cultivation period, the average external radiation of the glasshouse was $14.36MJ/m^2/day$ and the internal average temperature was controlled as $20.1^{\circ}C$. After 42 weeks of planting, the growth rate of 'Cupra' was 7.3 cm/week and that of 'Fiesta' was 6.9 cm/week. The first fruit setting of 'Cupra' appeared at 1.0th node and 'Fiesta' at 2.7th node. The first harvest of 'Fiesta' was 11 weeks after planting and 'Fiesta' was 14 weeks. Comparing the yield per 10 a until the end of the cultivation in July, 'Fiesta' was 19,307 kg, which was 2.4% higher than that of 'Cupra'. And the fruit weight ratio of over 200 g of 'Cupra' was 27.7% which was 7.7% higher than that of 'Fiesta'. The average required days to harvest after fruit setting of 'Cupra' was 72.6 days and 'Fiesta' was 63.8 days. According to the relationship between the average required days to harvest and the cumulative radiation (during from fruit setting to harvest), the more radiation increases the less required days to harvest increases after February. In terms of yield, 'Cupra' increased in yield as the cumulative radiation increased, while 'Fiesta' showed an irregular pattern. Cumulative radiation from fruit setting to harvest was negatively correlated with required days to harvest after February in both cultivars. But in relation to yield, there were difference between 'Cupra' and 'Fiesta'.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.178-181
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• 1996

A medicinal herb, Scutellaria baicalensis G., can be a potential cash crop if proper cultural practices are established with proper genotypes. In this report the current status and future measure in cultivation of Scutellaria baicalensis G. in the southern parts of Korea are illustrated. We hope that this report stimulates research to investigate for the establishment of not only cultural practices such as sowing period after harvesting of barley, fertilizer application, planting density, weed control, and disease and insect control but also ideotype and disease resistant genotypes for the high yield of the herb.