• Current Research on Agriculture and Life Sciences
• /
• v.19
• /
• pp.31-37
• /
• 2001

Uyeki(1928) classified Pinus densiflora into six ecotypes(Northeastem type, Middle-southern flat type, middle-southern upland type, Wibong type, Ankang type, and Geumgang type) based on the pine tree type. The bark color of Geumgang type was ash-brown color on the lower parts of stem and yellowed color on the upper parts of stem. We investigated the physicochemical properties of soil forests to obtain basic data for preservation of exellent pine (Pinus densiflora for. erecta Uyeki). The results were as follows; The soil texture of the Pinus densiflora for. erecta Uyeki forests were showed nearly as sandy loam, that is, sand, silt and clay were consisted of 72%, 15% and 13%, respectively. Soil acidity(pH 4.6) was lower than Korea average forest soil acidity(pH 5.2). The average contents of available phosphate was 11.7ppm at Sokwang-ri, 26.8ppm at Mt. Eungbong, 24.2ppm at Mt. Kumma. It was the lowest at Uljin(4.6ppm). The contents of carbon was 6.2% at Mt. Chungok, 6.1% at Mt. Eungbong. This value was more than average of Korea forest soil.

• Korean journal of applied entomology
• /
• v.37 no.2
• /
• pp.123-125
• /
• 1998

In peony fields located in Uisong and Yeongcheon distribution of Meloidogyne hapla was examined. Of 131 fields examined, M. hapla was isolated from 102 fields. In 57.8% of the infested fields, M. hapla density was higher 31 larvae1300 ml soil, the larval density isolated from upland fields were higher than those from paddy fields. Sandy loam soil harbored higher number of larvae than clay soil. Physio-chemical properties of soil might affect nematode population: High larval density was detected from those fields with low contents of OM, K+ and low pH. Fields infested with high larval densities required more lime than those with low or non infested fields.

• Journal of Environmental Science International
• /
• v.16 no.6
• /
• pp.751-761
• /
• 2007

This study is carried out through ecological situation of native Bupleurum latissimum habitats and the research of environmental conditions for conservation of native sites, restoration of alternative habitats and preliminary data for application of useful medicinal plant. Native Bupleurum latissimum habitats were distributed on lower and middle part of the mountain from Altitude 54m to 185m, and the directions of slope were researched as usually northen and western slope. As a result of phytosociological research in 12 stands of native Bupleurum latissimum habitats, they were seperated to two communities(Bupleurum latissimum typical community and Bupleurum latissimum-Galium spurium community) in accordance with containable rate of the organic matter and soil hardeness. Soil condition is usually constituted as loamy sand and clay loam. Bupleurum latissimum is propagated in valuable soil conditions. Bupleurum latissimum lives with Morus bombycis, Reynoutria sachalinensis in Bupleurum latissimum typical community and Thalictrum aquilegifolium, Stellaria media, Hedera rhombea etc. is appeared with Bupleurum latissimum in Bupleurum latissimum-Galium spurium community. Especially, companion species were researched as Aster glehni, Dystaenia takeshimana and so on. The flora of vascular plants in this study is 44 families, 88genus 82species, 2 subspecies, 14 varietas, 4 forma and total 102 taxa. Plants of compositae occupied 10.78% among whole of them.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.12
• /
• pp.1412-1415
• /
• 2012

Return signals of a ground penetrating radar(GPR) for mine detection at various frequencies and soil moisture contents are analyzed in this paper. We first compute the dielectric constant, conductivity and attenuation loss based on clay loam which is Korea standard soil. The mine-detection images of GPR at various frequencies are also obtained using the finite-difference time-domain(FDTD) technique. Then, the signal-to-clutter ratio(SCR) and received power of the radar are studied. It is shown that the variable frequency channels are suitable for a GPR to detect landmines at various soil conditions.

• Korean Journal of Soil Science and Fertilizer
• /
• v.9 no.2
• /
• pp.77-81
• /
• 1976

On a newly reclaimed acidic soil, investigation was made to find out the influence of lime and phosphorus application by a large quantity on the uptake of zinc by corn and its distribution in leaves and stem, under a factorial combination with two levels of zinc, lime, and phosphorus with three kinds of soil texture. The results are summarized as following, 1. The concentration of zinc in stem reflected the zinc uptake status of corn better than the leaves. The concentration of zinc in stem responded clearly to the treatments of lime and zinc, while those of leaves tended to be constant regardless of the application of lime and zinc. 2. The zinc uptake was not improved by compost application though it increased the yield of corn significantly. 3. The application of lime for neutralization of soil with low level of phosphorus application affected the yield of dry matter differently among different soils, slight increase on sandy loam soil, slight decrease on loam soil, and significant decrease on clay loam soil. The yield decrease on clay soil is considered to be due to the decreased availability of applied phosphorus owing to the large amount of lime applied.

• Korean Journal of Environment and Ecology
• /
• v.29 no.6
• /
• pp.923-928
• /
• 2015

This study was carried out to evaluate the physicochemical properties of different types of topsoil in forest ecosystems by damage pattern and analyse the possibility of using the topsoil as a planting ground construction material. There were 72 samples from 36 sites of 12 damaged areas and 36 sites of 12 non-damaged areas. The results showed that the physicochemical properties of topsoil from non-damaged areas of forest ecosystems were on an average clay loam~sandy loam in soil texture, showing $0.95{\sim}1.10Mg/m^3$ in soil bulk density, $35.7{\sim}44.0m^3/m^3$ in solid phase, 56.0~64.3 in soil porosity, 8.4~35.8% in aggregate stability, 5~13 mm in soil hardness, 5.3~6.1 in pH, 0.14~0.65 dS/m in EC, 0.28~0.42% in T-N, $14{\sim}22cmol^+/kg$ in CEC, $0.15{\sim}0.31cmol^+/kg$ in Ex. $K^+$, $2.07{\sim}2.84cmol^+/kg$ in Ex. $Ca^{2+}$, $0.45{\sim}1.97cmol^+/kg$ in Ex. $Mg^{2+}$, 17~96 mg/kg in Av. $P_2O_5$ and 3.2~5.6% in OM. On the other hand, damaged areas were on an average clay loam~loamy sand in soil texture, showing $1.54{\sim}1.75Mg/m^3$ in soil bulk density, $52.8{\sim}58.0m^3/m^3$ in solid phase, 42.0~47.2 in soil porosity, 4.2~22.5% in aggregate stability, 13~25 mm in soil hardness, 4.8~5.5 in pH, 0.13~0.62 dS/m in EC, 0.02~0.12% in T-N, $5{\sim}15cmol^+/kg$ in CEC, $0.11{\sim}0.18cmol^+/kg$ in Ex. $K^+$, $0.45{\sim}2.36cmol^+/kg$ in Ex. $Ca^{2+}$, $0.39{\sim}0.96cmol^+/kg$ in Ex. $Mg^{2+}$, 15~257 mg/kg in Av. $P_2O_5$ and 0.4~2.2% in OM. After conducting a comparison of physicochemical characteristics of non-damaged forest area and damaged areas, it was found that the physicochemical characteristics of damaged areas were more deteriorated compared to that of non-damaged areas. Therefore, it is judged that it is necessary to establish countermeasures for the conservation and management of the damaged areas for topsoil recycling in the future.

• Asian Journal of Turfgrass Science
• /
• v.16 no.1
• /
• pp.31-40
• /
• 2002

This study was conducted to analyze the correlation of soil physical properties and growth of turfgrass on the ground of Olympic-mainstadium. Soil hardness and turf visual quality were measured at 77 plots (10m x 10m divided each) independently and analyzed correlation later. Physicochemical properties of the topsoil analyzed from three typical levels of the severely, moderately, slightly compacted areas. The ground showed high hardness at the center circle and the goal line, but low at the end line areas. On the contrary, visual quality rate of turfgrass was low at the center circle and the goal line, but high at the end line areas. The correlation was shown a significant negative value on soil hardness between turf visual quality Soil hardness seems to be accelerated by the improper soil texture of sandy loam which contained a large amount of finer particle of silt (10.7%) and clay (11.1%) which values exceeded for USGA (United State Golf Association) recommendation. Deterioration of turf quality resulted initially from improper construction and followed by high soil compaction with continuous uses of the ground without proper maintenance. To perform the international quality of the turf ground, the initial construction procedures should be followed by standard specifications of sport ground.

• Korean Journal of Soil Science and Fertilizer
• /
• v.26 no.3
• /
• pp.155-159
• /
• 1993

This study was initiated to obtain the scientific information for the improvement of paddy soil. Mean values and mutual relationships of bulk density, pH values and the content of organic matter were investigated at the 124 field sites shown to be nationwide high-yielding, young seedling field s and their neighboring fields under the different soil textures and depths. The soil samples were collected and those samples were analyzed in the laboratory of Agricultural Sciences Institute. Mean values among the different soil textures and depths were estimated with loam-textured. Bulk density were significantly correlated with sand and silt in topsoil, and that were appeared to be correlated to sand, silt + clay, pH and content of organic matter highly significant in 1% level. Regression equation of soil bulk density(Y) to clay(C), orgnic matter (OM) and content of silt + clay(S+C) were as follows for the topsoil, Y=1.365+0.006C-0.003(S+C)~0.034OM (R=0.067*), and for the subsoil, Y=1.548 -0.002C-0.0007 (S+C) -0.036OM (R=0.122**).

• Korean Journal of Weed Science
• /
• v.6 no.2
• /
• pp.146-153
• /
• 1986

The study was conducted to estimate the oxyfluorfen inactivation proceeding which have or have not organism and soil microorganism in soil by biological testing method, under the different condition of soil class and temperature. The results obtained in this experiment are as follows: 1. Under the condition of high temperature, chemical`s inactivation resulted in early and the extent of it`s inactivation was increased. 2. The extent of inactivation was more rapid in the sandy soil than in the clay. 3. Among the soil class, the differentiation of the day of demand with inactivation at the 50% and 95% was significantly increased low temperature period. 4. In sandy soil, inactivation`s differentiation by adding organism was found, but by adding microorganism was not found. 5. In clay, chemical's inactivation was increased rather by adding microorganism than by adding organism. 6. Among under the condition of soil class, by adding organism and micrrorganism, chemical`s inactivation (Probit growing period at 50% and 95%) was shorted. And among the soil class, it was shortter sandy soil than clay or silty loam soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.1
• /
• pp.45-52
• /
• 1989

The effects of soil properties and N, P and K application rates on the contents of inorganic constituents in the rhizomas of Ji-whang were investigated to know the condition for producing the better quality rhizoma of Ji-whang. Most of soil texture for Ji-whang cultivating belongs to sandy clay loam and sandy loam soils. The nitrogen contents in the rhizomas of Ji-whang was negatively correlated with the contents of organic matter and total nitrogen in surface soils, whereas positively correlated with the sand contents in subsoils. The calcium contents in the rhizomas of Ji-whang were negatively correlated with the sand contents, however, positively correlated with the contents of clay and organic matter in soils. The iron contents was positively correlated with the contents of clay, available phosphorus and exchangeable potassium in surface soils. Much more contents of the inorganic constituents in the leaf of Ji-whang was generally detected than that in the rhizoma of Ji-whang. The contents of iron and copper in the leaf was determined to be more than that in the rhizomas by ten times. In the results of field experiments, it is apparent that the nitrogen contents in the rhizoma and leaf increased with increasing N application rate more than 20kg/10a and 10kg/10a, respectively.