• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.493-499
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• 2010

To obtain the basic data for the conservation and cultivation of major native herb species under the trees, distribution of native herb species, and corrrlations between native herb species and site factors were studied on natural broadleaved forest in Mt. Gariwang and Mt. Jungwang, Pyeunchang-gun. 136 native herb species were distributed in studied area, and the importance percentage of Pseudostellaria heterophylla was proved the highest, 10.8%. The other major herb species were the following oders, Meehania urticifolia, Corydalis remota, Pimpinella brachycarpa, Carex siderosticta, Pseudostellaria palibiniana, Erythronium japonicum, Ligularia fischeri, Asarum heterotropoides var. mandshuricum, Hylomecon vernalis and Astilbe rubra var. rubra. Highly positive correlations were proved Hepatica asiatica and Ainsliaea acerifolia, Pimpinella brachycarpa and Aconitum jaluense subsp. jaluense, Aconitum jaluense subsp. jaluense and Smilacina japonica var. japonica, Meehania urticifolia and Pseudostellaria palibiniana. Seven groups of native herb species were divided by cluster analysis. Preferring site factors for each native herb species were determined. Ligularia fischeri, Ainsliaea acerifolia, Parasenecio auriculata var. matsumurana, Erythronium japonicum and Pimpinella brachycarpa were distributed mainly on the higher sites, Ligularia fischeri were ditributed more frequently in deep soil sites. These results might be useful measures in the conservation and cultivation of native edible and medicinal herb species on the forest floor in the natual broadleaved forest, Pyeungchang-gun.

• Korean Journal of Ecology and Environment
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• v.50 no.2
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• pp.195-206
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• 2017

We described a spatial distribution pattern and floral diversity on the Paspalum distichum community occurring at the ecological parks of Hwamyeong, Daejeo, Samnak, and Maekdo in the Nakdong river estuary. A total distribution area of P. distichum community was $303,462.6m^2$. Its largest area was found in Samnak eco-park ($185,910.1m^2$). The most richness of knotgrass patches in each ecological park was determined Maekdo eco-park (87). Cover class level-5 shows the largest area ($260,663.2m^2$). A total of 73 taxa (34 families, 55 genus, 65 species, and 8 varieties) were listed up on the P. distichum community. A welldeveloped population of knotgrass was found predominantly at sites linked into human impacts at the riverine floodplain, the stream courses flowing through the parks, and the man-made channels and wetlands. Finally we proposed an ecological management strategy for knotgrass population in the study area.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.72-77
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• 1994

This study was conducted to investigate the influence of treatment of fly ash on heavy metal contents of the arable soil. Rice was cultivated on the two types of paddy field clay loam and sandy loam with 0, 12ton/10a of anthracite fly ash and bituminous coal fly ash application. And soybean was cultivated at the same type of upland fields with those ashes of 0, 9ton/10a, yearly for three years. At the harvest time, the heavy metal contents in the different layer were investigated. The results were summarized as follows : 1. The contents of some heavy metal were increased in the surface soils but didn't show the tendency in the deeper layer or soil texture. 2. In the paddy fields, the contents of Cd, Cu, Zn, Cr were increased. Meanwhile and the upland fields, the contents of Cd and Cr were increased with the successive application of Anthracite fly ash, but the others didn't show those tendency. 3. The contents of Cd, Cu and Zn in the paddy field, were increased but the upland field, the contents of Cd, Cr and Ni were increased by the successive application of bituminous coal fly ash.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.105-110
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• 1994

Field experiment was carried out to obtain the basic information on the soil improvement with different improved methods on job's tears yield and soil properties in the newly-reclaimed land from 1985 to 1988. Job's tears yield, soil properties and annual changes of soil were investigated and analyzed. Soil bulk density and hardness of topsoil decreased from 1st year to 3rd year, but those increased in 4th year. Soil pH of topsoil had no differences in different soil depths and cultivated years. Average yield of job's tears in the integrated improvement plot was 2.16ton/ha. That was increased by 49% than the control plot. Crop yield was greatest in order of integrated improvement>subsoiling>phosphate>lime>compost>control plot. Correlation coefficients of job's tears yield with soil pH and organic matter content were higher significantly. Also those of subsoil were higher than topsoil. Ratios of annual changes of soil bulk density and hardness showed significant highly with job's tears yield. Also that soil pH was significant at 5 % level in the topsoil.

• Horticultural Science & Technology
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• v.18 no.5
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• pp.599-604
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• 2000

This experimemt was conducted to determine the effect of ridge-up bed with different height (0, 20, 40, 60 cm) on the fruit quality of 'Miyagawa Wase' satsuma mandarin cultivated in a plastic film house. Soil moisture was measured at the soil depths of 10, 30, and 60 cm for each height of ridge-up bed. The time required to reach the condition, -1.4 Mpa at 30 cm deep in soils, which are supposed to be the ideal soil moisture potential and soil depth for high quality satsuma mandarin production, was 100, 60, and 30 days for 20, 40, and 60 cm ridge-up bed, respectively, and more than 100 days for 0 cm. Peel chromaticity by 'a' value was increased as the ridge-up height went up, so that plants grown at the bed with 60 cm height had 11 degree higher value than those of plants grown at the bed with 0 cm height. The 'a/b' values also had a similiar trend as value 'a'. The reducing sugar level of the fruit juice, which was composed of glucose and fructose, was increased as the height of ridge went up, showing significant difference between the ridge heights. The sucrose level had the same trend as the reducing sugar level although the difference between the ridge heights were not significant. Generally, the soluble solid level is considered to be representing the fruit quality. It had 11.4, 12.1, 12.5, $12.8^{\circ}Brix$ for 0, 20, 40, and 60 cm ridge-ups, respectively, showing $1.4^{\circ}Brix$ difference between 0 and 60 cm ridges. Acidity basically showed the same result as that of the soluble solid level depending on the height of the ridges.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.45-53
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• 1984

This experiment has been made to find out the influence of soil bulk density on growth and root development of Populus alba ${\times}$ P. glandulosa in Buyeo-kun, Chungnam. Bulk density and porosity significantly change according to slope position and soil depth and have a significant effect on tree height, DBH, biomass, and the distribution of root development. The results extracted from the experiments are as follows; 1) Bulk density in average changes from $1.17g/cm^3$ (1.05 ~ 1.40) in lower slope position to $1.43g/cm^3$ (1.36 ~ 1.60) in upper slope position, and porosity from 52.65% (55.05 ~ 45.50) in lower slope position to 41.20% (43.81 ~ 37.21) in upper slope position. 2) Bulk density increases significantly with soil depth. 3) Tree height, DBH, and total biomass decrease with bulk density. 4) Foliage, branch, bolewood, bolebark, and root also significantly have a negative correlation with hulk density. 5) Populus alba ${\times}$ P. glandulosa has a shallow root system chiefly distributing only in AI horizon, and critical bulk density is $1.43g/cm^3$. Therefore, slope position, hulk density, and porosity are considered to influence on the growth, biomass, and root development of Populus alba ${\times}$ P. glandulosa.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.375-382
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• 2014

The objective of this study was to investigate suitable plantation site for planted Chamaecyparis obtusa seedlings from the analysis of regional early growth performances. Two years old C. obtusa seedlings were planted with the density of $3,900seedlings{\cdot}ha^{-1}$ in late March, 2011 at Haeman and Jangseong, Jeollanamdo. In each study site, three plots ($400m^2$ per plot) were established and root collar diameter (mm) and tree height (cm) of each C. obtusa were measured in April, 2011 and October from 2011 to 2013. We also analyzed soil physical and chemical properties of sites and compartmental nitrogen and phosphorus concentrations of C. obtusa. Although the concentrations of soil nitrogen, organic matter, and C.E.C. at Haenam site were higher than those at Jangseong site, early growth performances of planted C. obtusa at Jangseong site were significantly better than those at Haenam site. The reasons for these results were probably related to deep available soil depth at Jangseong site and relatively low annual precipitation and sea wind at Haenam site, which was adjacent to the sea. The compartmental nitrogen and phosphorus concentrations of C. obtusa was in the order of needles > current twigs > fine root > stem and branches root above 2 mm in diameter. The phosphorus concentration of needles at Haenam site was significantly higher than that at Jangseong site. The results of this study might be useful for the selection of suitable plantation site for C. obtusa.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.269-276
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• 2001

Several experiments including persistence, distribution, leaching, and terminal residue trials were carried out to investigate the behavior of cyclosulfamuron in rice paddies. Cyclosulfamuron was gradually dissipated in two different soils showing the first-order kinetics. Half-lives of the herbicide were calculated to be $17{\sim}30$ and $14{\sim}16$ days under field and laboratory conditions, respectively. In the paddy soil/water system, the residue tended to reside more in the soil phase as time elapsed. Cyclosulfamuron was less persistent in paddy water than in soil with half-lives of 10 and 19 days, respectively. No cyclosulfamuron was leached below 20 cm-deep soil during water percolation with 50 cm hydraulic head, while some downward mobility was observed within the soil column. When EC and SC formulations of cyclosulfamuron were applied to the paddy field at 120 or 150-day pre-harvest intervals, its terminal residues in hulled rice were all less than 0.01 mg/kg, irrespective of formulation type and application timing. In rice straw, however, some residues were found at $<0.02{\sim}0.05$ mg/kg as SC formulation was applied. Rapid dissipation, restricted mobility, and low terminal residues of cyclosulfamuron in rice paddies suggest that no significant residues would be transported or carried over to the non-target environment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.710-717
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• 1996

To obtain the basic informations on the farm cultivation of Eleutherococcus senticosus Max., field survey of the native habitat in Mt. Deokyu such as weather, soils, vegetation and growth was carried out. The habitat of E. senticosus is situated at 127$^{\circ}$ 45'E, 35$^{\circ}$ 52' N in Mt. Deokyu where the elev-tion ranges from 1,050 to 1,300 meters above the sea level. Mean annual temperature forecasted around the habitat was 5.8$^{\circ}C$, mean maximum temperature in August, 24.6$^{\circ}C$ ; mean minimum temperature in January, -13.5$^{\circ}C$ and relative humidity during the growth periods, over 95%. To divide the area according to climatic conditions was classified cool temperature and humid rain forest zone. In another view, it belonged to deciduous broad-leaf forest zone and soil texture was sandy loam with dark brown gravels. Acidity and P$_2$O$_{5}$ content of soil represented pH 5.2～5.6 and 10ppm, respectively. The growth of E. senticosus was poor under the low light intensity(relative 20% of full sun-light) at the growing place of the habitat and the propagation was conducted by root sucker. The natural vegetation was consisted of big trees, 3 species; shrubs, 8 species and herbs, 4 species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.430-435
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• 2012

Low silage corn yield due to bad soil physical properties in the paddy field converted to upland condition is the chief obstacles to expanding the area for silage maize production. The effect of subsoiling (subsoiling to depth 40 cm) on soil physical properties and silage corn yield were investigated in the first year of paddy field converted to upland condition in 2010 and 2011, respectively. Soil compaction was loosened much particularly at depth 25~35cm as much as 1~1.5 MPa and soil bulk density and porosity at depth 15~30 cm are improved by subsoiling. Maize growth was increased by subsoiling, particularly in kernel number per ear which increased ear weight. Total digestible nutrients (TDN) yield of silage maize was increased as much as 19 and 39% in 2010 and 2011, respectively showing that yield increase according to subsoiling was higher when maize growth was prohibited much by excess-moisture injury due to heavy rain in 2011.