• Journal of Forest and Environmental Science
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• v.39 no.2
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• pp.96-104
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• 2023

The successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. Below-ground is hypothesized to have a major impact on seedling performance of species when planted in agriculture, and degraded areas with different types of mulching. This study investigated on Sg. Terla Forest Reserve in Cameron Highlands Pahang, Malaysia. In this study randomized complete block design (RCBD) was used. The excavation method was applied to study the root system development, above, and below ground biomass distributions under different types of mulching: coconut mulching (CM), oil palm mulching (OM), plastic mulching (PM) and control (CK). The root diameter, main root length, lateral root length, root coiling, and root direction toward to sun were recorded. The results in this study indicate that mulching had significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length, root: shoot ratio, dry biomass distributions, and above and below ground biomass did not showed significant effect among treatments. The highest values for root diameter, lateral root length, main root length, root distributions, dry biomass distributions and above and below ground biomass were showed in CM treatments. However 75% of root coiling was observed in seedlings between treatments.

• Journal of Plant Biology
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• v.14 no.3
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• pp.29-35
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• 1971

Various types of short culm rice mutants were obtained by means of gamma-ray irradiation. In the present paper morphological observation and analysis of silicate content of the mutants are reported. 1. Short culm type had more useful characters than bushy and dwarf types. 2. In short culm and bushy types the number of nodes both above and under ground was similar to the mother varieties, while in dwarf type it decreased. 3. In short culm types the variation of length of above-ground culm and internodes tended to vary relattive to the mother varieties. 4. Positive correlation was found between culm length and the first and fourth internode length in short culm type. 5. Silicate content increased in short culm type-the increment being variety specific.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.42-51
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• 2011

This study was conducted to analyze correlation of above- and below-ground biomass and to drive regression equation suitable for estimating standing tree biomass between natural and planted stands of Pinus densiflora for. erecta of one age-class in Gangwon province, Republic of Korea. Total 40 trees, 10 from the naturally regenerated and 10 from the planted stands in each of two studied sites, were uprooted to measure height, diameter at root color (DRC), and the dry weights of stem, branches, and needles. The length, weight, and volume of the main and horizontal roots were also measured. Most of the above-ground traits except height were highly correlated with most of the other above-ground traits and the below-ground traits except the length of roots (p < 0.05). Especially, the DRC, which is measured easily on the standing tree, was highly correlated with most of the traits in all studied stands (p < 0.01). Thus, the DRC would be the most desirable trait to estimate not only above-ground biomass but also below-ground biomass. However, height was not a good variable to estimate standing tree biomass of Pinus densiflora for. erecta of one age-class in Gangwon province because it was not correlated with most of other traits. Regression equations derived from the current study could be used effectively as a basic data for estimating above-ground and below-ground biomass using DRC.

• Journal of the Korean Wood Science and Technology
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• v.26 no.2
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• pp.45-50
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• 1998

Tracheid length, microfibril angle, and compression strength were examined in south and north sides of Pinus koraiensis. The sample tree was 57 years old and had been planted in central Korea. Tracheid length on the south side of the tree ranged from 2.87 to 3.40mm and on the north ranged from 3.60 to 3.53mm and mean values were 3.15 mm for the south and 3.26mm for the north. Tracheid length was 0.11 mm longer on the north side than on the south. Microfibril angle on the south side ranged from $12.6^{\circ}$ to $20.3^{\circ}$ and that on the north from $6.8^{\circ}$ to $13.5^{\circ}$; mean values were $16.6^{\circ}$ on the south side and $9.6^{\circ}$ on the north. Microfibril angle was $7.0^{\circ}$ greater on the south side than on the north side. For compression strength on the south and north sides, significant difference at the 95% level was found only at l.3m above the ground level of the sample tree; for compression limit stress, significant difference at this level was found at 1.3 and 5.3m above the ground level. However, compression strength and compression limit stress were greater on the north side than on the south side.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.338-345
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• 2001

This study was conducted to elucidate the relationship between the root structure and the crown structure of Norway spruce(Picea abies [L.] Karst), and thereafter to obtain the regression equation for the estimation of relative root and needle biomass using the tree height and diameter at breast height(DBH) without measurement of root and needle biomass. The study site was Barbis stands of Harz region located in central part of Germany. Five dominant and three co-dominant trees of 30 to 40 year-old Norway spruce were selected and tree height, diameter at breast height, clear bole length, weight of total needle and branch, cross section and sapwood area at breast height for biomass of above ground part and also the length of root, the number of root, the weight of root, the cross section area of root etc. by dividing the horizontal and vertical roots for below ground part of tree were measured. The significantly correlation was shown between the biomass of most of variables of above ground parts and those of below ground parts. For the diameter of breast height to the weight of total root, regression equation was Y = 3.56X - 45.94 and decision coefficient was 0.96 showing highly correlation. The weight of total branches and needles, and the tree height etc. of above ground parts showed highly positive relationship with below ground biomass. The results obtained from this study can be used to the estimating of biomass of below ground using variables of above ground such as DBH in the 30 to 40 year-old Norway spruce stands.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.745-751
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• 2009

The anchor is used extensively for a cutting slope, an earth retaining wall, an uplift resistance of sub-structures and so on at civil engineering projects and is classified by aim in use, tendon material, and ground/tension fixing type. It can be distinguished extensively into friction type, bearing type, and complex type by ground fixing type. Generally, bond length of friction type anchor has application to 3~10m depending on the friction-resistance characteristics. In this study, 'DEW(double enlargement wedge) bearing type anchor' of new concept is devised. The bond length is about 0.6~0.8m. It can be used on the ground to have the strength characteristics above it of weathered rock. There are merits which are 'period reduction' and 'cost saving' through the minimum of the boring length. In addition, it is so called environmentally friendly Methods because it can reduce the quantity of carbon dioxide through the reducing drilling machine operation time.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1248-1256
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• 2008

In this paper, basic characteristics of transmission line employing PPGM (periodically perforated ground metal) were investigated using theoretical and experimental analysis.According to the results, unlike the conventional PBG (photonic band gap) structures, the characteristic impedance of the transmission line employing PPGM structure showed a real value, which exhibited a very small dependency on frequency. The transmission line employing PPGM structure showed a loss (per quarter wave length) higher by $0.1{\sim}0.2\;dB$ than the conventional microstrip line. According to the investigation of the dependency of RF characteristic on ground condition, the RF characteristic of the transmission line employing PPGM structure was hardly affected by the ground condition in the frequency lower than Ku band, but fairly affected in the frequency higher than Ku band, which indicated that coplanar waveguide employing PPGM structure was optimal for RF characteristic and reduction of size. Considering above results, impedance transformer was developed using coplanar waveguide with PPGM structure for the first time, and good RF characteristics were observed from the impedance transformer. In case that {\lambda}/4$ impedance transformer with a center frequency of 9 GHz was fabricated for a impedance transformation from 20 to10 {\Omega}$, the line width and length were 20 and $500\;{\mu}m$, respectively, and its size was only 0.64 % of the impedance transformer fabricated with conventional microstrip lines. Above results indicate that the transmission line employing PPGM is a promising candidate for a development of matching and passive elements on MMIC.

• Ocean and Polar Research
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• v.44 no.2
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• pp.127-137
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• 2022

This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m²/yr, and the highest production was 519 gDWt/m²/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m²/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.185-189
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• 2009

This study was carried out to investigate the effect of shading (50% or not) and pruning height (3cm, 6cm, and 9cm) of remained above-ground plant part on shoot emergence aspect, mortality rate, flowering and cut flower characteristics of two years old Gypsophila paniculata plants. Days to shoot emergence (80%) advanced, emerged shoot number increased and mortality rate surveyed on late October decreased in 50% shading treatment. In addition to, mortality rate decreased, as above-ground plant part was highly pruned. Blooming was earlier with highly pruning the remained above-ground pan and under non-shading condition than shading. Growth traits such flower stalk length, primary branches number, stem diameter, and cut flower yield were the best and also non-particulate rate and rosette formation rate were the lowest in pruning height of 9cm under non-shading condition.

• Journal of Ecology and Environment
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• v.45 no.2
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• pp.78-87
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• 2021

Background: To understand shade and wind effects on seedling traits of common reed (Phragmites australis), we conducted a mesocosm experiment manipulating day length (10 h daytime a day as open canopy conditions or 6 h daytime a day as partially closed canopy conditions) and wind speed (0 m/s as windless conditions or 4 m/s as windy conditions). Results: Most values of functional traits of leaf blades, culms, and biomass production of P. australis were higher under long day length. In particular, we found sole positive effects of long day length in several functional traits such as internode and leaf blade lengths and the values of above-ground dry weight (DW), rhizome DW, and total DW. Wind-induced effects on functional traits were different depending on functional traits. Wind contributed to relatively low values of chlorophyll contents, angles between leaf blades, mean culm height, and maximum culm height. In contrast, wind contributed to relatively high values of culm density and below-ground DW. Conclusions: Although wind appeared to inhibit the vertical growth of P. australis through physiological and morphological changes in leaf blades, it seemed that P. australis might compensate the inhibited vertical growth with increased horizontal growth such as more numerous culms, indicating a highly adaptive characteristic of P. australis in terms of phenotypic plasticity under windy environments.