• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.91-98
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• 2001

Scutellaria baicalensis G. was cultivated in plots of different soil textures which were sand loam(SL), loam(L) and clay loam(CL). Also three fertilizer conditions were used; non application (NA)treatment, rice straw manure(RSM) treatment and N-P-K, chemical fertilization(CF) treatment. The chemical-physical properties, such as organic matter, available phosphate, $K_2O$, CaO, clay contents and porosity ratio in CL plot with RSM application were the most proper in CL plot and RSM application for the culture of S. baicalensis plants. RSM had very high contents of total nitrogen, 2.25% and C/N ratios, 21.4. Thus the growth of shoot and root in loam plot with RSM treatment were greater compared to that of CL plot with NA treatment. Whereas, The highest baicalin, baicalein and wogonin contents in roots were found in CL plot with RSM treatment. There was significantly positive correlation between aerial and underground parts of plant, yield and contents of T-N, $K_2O$ but negatively correlated with the contents of baicalin, baicalein and wogonin in S. baicalensis roots.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.267-271
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• 2003

Burkholderia sp. D5, a polyaromatic hydrocarbons(PAHs)-degrading bacterium, was isolated from oil-contaminated soil. The bacterium could utilize phenanthrene (Phe) as a sole carbon source but could not use pyrene (Pyr). However, the strain could degrade Pyr when a cosubstrate such as yeast extract (YE) was supplemented. The PAH degradation rate of the bacterium was enhanced by the addition of other organic materials such as YE, peptone and glucose. YE was a particularly effective additive in stimulating cell growth as well as PAH degradation. When 1 g-YE/L was supplemented into the basal salt medium (BSM) with 215 mg-Phe/L, the specific growth rate (0.28 h-1) and Phe-degrading rate (29.30 μmol/L/h) were enhanced approximately ten and two times more than those obtained in the BSM with 215 mg-Phe/L, respectively. Through kinetic analysis, the maximum specific growth rate (μmax) and PAH degrading rate (Vmax) for Phe were obtained as 0.34/h and 289 ${\mu}mol$/L/h, respectively. Also, μmax and Vmax for Pyr were 0.27 h-1 and 50 ${\mu}mol$/L/h, respectively. The degradation rates for each Phe (2.20 μmol/L/h) and Pyr (2.18 μmol/L/h) were lower in mixture substrates than in a single substrate (29.30 ${\mu}mol$/L/h and 9.58 ${\mu}mol$/L/h, respectively). Burkholderia sp. D5 can degrade Phe and Pyr contained in soil, and the PAH degradation rates in soil were 20.03 ${\mu}mol$/L/h for Phe and 1.09 ${\mu}mol$/L/h for Pyr.

• Korean Journal of Environmental Agriculture
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• v.5 no.1
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• pp.48-54
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• 1986

Because of the drastic development of nuclear industries, the contamination of natural environments by the disposal of radioactive materials which are released from nuclear facilities have aroused a considerable concern in relation to agricultural practices. Therefore the present investigation, through pot experiment, was performed to find out the aspect of the uptake of $Sr^{90}$ by rice plants and its distribution in them in five different types(physicochemical and minerallogical properties) of paddy soils. The results obtained were as follows; 1) Visual toxic symptoms on the growth of rice plant due to treatment of $Sr^{90}$ up to $40{\mu}Ci/10㎏$ in a pot were not observed even though uptake of $Sr^{90}$ by rice plant was proportionally increased with the $Sr^{90}$ treatment. 2) Distribution of $Sr^{90}$ in the rice plant was the highest in the leaves (84.5%) followed in the order by stems (13.5%) and rough grain (2.0%). The ratio of $Sr^{90}$ to Ca was higher in the leaves (872) and stems (667) than in the rice grain (89). 3) $Sr^{90}$ absorption in the rice plant ranged $0.15{\sim}0.30%$ at harvesting time. Uptake of $Sr^{90}$ by rice plants decreased by the increase of soil pH and exchangeable canons in the soils, but $Sr^{90}$ uptake increased when nitrogen, organic matter and clay content in soil was high, and uptake of this nuclide in the rice plant was higher with low Illite and Vermiculite content in the soils.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.100-110
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• 2003

This study was conducted to evaluate influence of chemical properties in the riparian on the species diversity and to get plant information for enhancement of natural purification in Mankyeong River. The concentration of total nitrogen was high in Jeonju and Sam stream, while that of total nitrogen showed the highest peak in Winter. Concentrations of $NH_4-N$ was $0.01{\sim}0.06\;mg/L$ in Gosan and Soyang stream. The water quality of upstream along with Mankyeong River was suitable for the irrigation source. The riparian vegetation was investigated by Zurich-Montpellier school's method from June, 2001 to September, 2002. The number of riparian plants were 59 families, 129 genera, 165 species, 20 varieties in Gosancheon, on the while 53 families, 111 genera, 141 species, 19 varieties in Soyangcheon. The number of riparian plants in Bari basin was higher than that of other sites namely, 73 families, 134 genera, 218 species, 33 varieties. Riparian vegetation was consisted of 12 plant communities. The contents of organic matter, total nitrogen and electrical conductivity had negative relationship with species diversity (Species richness index, Heterogeneity index, Species evenness index Species number). On the while, species diversity had positive relationship with soil pH. Species diversify of the plant communities were affected by topography and disturbance.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.174-181
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• 1998

In four citrus grow of Satsuma mandarin (rootstock of trifoliate orange) including two grove of organical management and two groves of conventional management, spores of arbuscular mycorrhizal(AM) fungi were identified and seasonal changes in spore density in soils and AM colonization of citrus roots were investigated. AM colonization in weeds found in the groves were also examined. Three species of Glomus (G.deserticola, G. vesiculiferum, G. rubiforme ) and one unknown species of Acaulospora were observed in all of the groves. Annual mean density of AM fungal spores were in the range of 10,000${\sim}$40,000 per 100g soil with more spores in the organically-managed groves. The least spores were observed in December in all groves, and the most spores in April in the organically-managed groves while in February or April in the conventionally- managed. Annual mean AM colonization more 27% of citrus root were observed in the organically-managed with the high peaks in April and October and the minimum in August, while mean colonization less than 15% in the conventionally-managed with the peak in February and the minimum in different times depending on groves and years. AM colonization corresponded to a sigmoidal curve consisting of a laf phase during winter and a subsequent increase in spring, then succeeded by a maximum, and then a decrease at the end of vegetation. Fungal spore density and AM colonization showed a parallel pattern during the sample period. The seasonality appeared to be related more to the phenology of the plant than to the soil factors. Generally more spore density and AM colonization were found in organically managed groves. AM colonization was not correlated with available P and organic matter content in soil in this field investigation. Among sixteen weed species found in the groves, Astrogalus sinicus of Leguminosae, Portulaca oleracea of Portulacaceae showed high colonization in all groves and they can be considered as a source of inoculumn and host plants for propagation of AM fungi.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.33-40
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• 2009

From 2006 to 2008, natural habitat of Sparassis crispa were surveyed for investigating ecological conditions at sixteen different sites in Korea. The investigated sites showed very wide altitudinal distribution ranged from 240 meters to 1,100 meters above the sea level. In general, S. crispa showed distinct feature of heart-rot fungi as it occurs on soils around the stems of larch (Larix kaempferi) and Korean white pine (Pinus koraiensis). But it also could be found on stems or on the stumps of dead trees, which indicated that the fungus might have several invasion routes and capabilities to grow on various ecological conditions. All of the sixteen sites were pure stands consisted with conifers such as larch or Korean white pine. The dominant tree layer showed $15.3{\sim}38.0$ meters for tree heights, thicker than twenty centimeters for the diameter at breast height (DBH), and all of them were older than thirty years. Since the stands were pure stand, species diversity of trees in the sites was extremely low. While the dominant tree layer showed only pure coniferous stand, the co-dominant tree layer, shrub layer and herbaceous layer showed more diverse features with higher Shannon-Wiener (H') indices. Soil texture of thirteen sites among sixteen investigated sites were loamy soils, and the contents of organic matter in soil were more or less higher than general forest soils in Korea with $3.79{\sim}14.32%$. The cation exchange capacity (CEC) was also relatively higher than general forest soils with $16.1{\sim}27.2$ cmol+/kg. The data indicated that the cauliflower mushroom occurring sites were relatively fertile than general forest soils. The soils were acidic with pH ranged from 4.2 to 5.2, which were typical features for conifer stands in Korea.

• Journal of Life Science
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• v.27 no.4
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• pp.390-397
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• 2017

Iron (Fe) is an important micronutrient for the health and growth of plants. Iron is usually provided by fertilizers, and iron-chelate fertilizers are well absorbed by plants. This study presents the plant growth-promoting effects of a new functional iron fertilizer, Fe-chelating crab shell powder (FCSP), which is generated from the chelation of Fe ions with crab shell powder. Iron chelate was derived from spent pickling liquor, which is rich in reductive iron, iron(II) oxide. To analyze the effects of FCSP on plant growth, we treated lettuce with several concentrations of FCSP in both lab- and field-scale experiments. In the lab-scale test, the treatment of 50 ppm of FCSP highly promoted growth and resulted in increases in the size, weight, number and chlorophylls content of leaves of plants compared to the treatment of crab shell powder. Fifty ppm of FCSP also increased the size and weight of leaves up to 2 times compared to the application of chemical fertilizer and/or compost in field conditions. In addition, the FCSP treatment resulted in the highest ion uptake of Fe in lettuce leaves. Moreover, FCSP led to increases in the amounts of Fe, Ca, available phosphorus and organic matter in treated soil, indicating that soil quality was improved. Taken together, our results demonstrate that FCSP promotes lettuce growth via enhancement of Fe availability and improves soil quality. Therefore, FCSP can be utilized as a new functional iron fertilizer.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.43-71
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• 1999

This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.153-164
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• 1999

The solubilization of BTEX was evaluated in aqueous surfactant solutions with and without several additives. Anionic surfactant(Sodium Dodecyl Sulfate, SDS) and nonionic surfactants (NEODOL(equation omitted)25-3 and $SOFTANOL\circledR-90$ were used as test surfactants. The effects of surfactant HLB(Hydrophile-Lipophile Balance) Number and hydrocarbon molar volume and polarity of BTEX on the MSR(Molar Solubilization Ratio), micelle-water partition coefficient of BTEX, and CMC(C,itical Micelle Concentration) were investigated. Optimizing treatment conditions applicable to enhanced solubilization was also studied by manupulating salinity or electrolyte control with additives of ethyl alcohol, hydrotrope, and electrolyte solution. The most effective surfactant for solubilization was found $SOFTANOL\circledR-90$, since HLB number of 13.6 is similar to those values of BTEX ranging between 11.4 and 12.2, which was also proved experimentally. Ethyl alchohol of 3% was the most effective additives in reducing CMC and improving solubilization among the conditions using SDS, NEODOL(equation omitted)25-3, and $SOFTANOL\circledR-90$ with three additives. The partitioning of BTEX between surfactant micelles and aqueous solutions was characterized by a mole fraction micelle-phase/aqueous phase partion coefficient, $K_m$. Values of log $K_m$. for BTEX compounds in surfactant solutions of this study range from 2.95 to 3.76(100mM SDS) and 2.95 to 3.49(117mM $SOFTANOL\circledR-90$. Log $K_m$ appears to be a linear function of log $K_{ow}$ for SDS and $SOFTANOL\circledR-90$. A knowledge of partitioning of BTEX in aqueous surfactant system can be a prerequisite for the understanding of the behavior of hydrophobic organic compounds in soil-water systems in which surfactants play a role in remediation of contaminated soil and facilitated transport.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.129-136
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• 2010

This study was initiated to investigate thatch accumulation in several turfgrasses grown under two soil systems. The 45 centimeter deep USGA system was constructed with rootzone, intermediate and drainage layers. The mono-layer system, however, was made with only a 30cm rootzone layer. Turfgrasses used in the study were comprised of 3 varieties from Korean lawngrass of Warm-Season Grass(WSG) and 3 blends and 3 mixtures from Cool-Season Grass(CSG). A total of 9 turfgrass treatments were replicated three times in RCBD in both systems. Cultural practices for the research plot followed a typical maintenance program for highly managed turf. Treatment differences for thatch accumulation were observed among the turfgrasses in both soil systems. Thatch under the USGA system was 9% greater than under the mono-layer system due to its more favorable conditions for turf growth. Higher thatch depth was found with Korean lawngrass, 34~87% in the USGA system and 16~75% in the mono-layer system when compared with CSG. Among WSG, the Joongji variety was the highest in thatch layer under both the USGA and mono-layer systems. Kentucky bluegrass(KB) was the greatest among CSG, since it is a rhizomatous-type in growth habit, resulting in faster production of organic matter over bunch-type of tall fescue and perennial ryegrass. Proper depth in the thatch layer was known to be beneficial by enhancing the resiliency and wear tolerance of the turf in athletic fields. Thus, KB was considered to be a very excellent turfgrass in terms of turf quality, environmental performance, physical properties and soccer player safety. However, disadvantages such as poor water-holding properties, more inclined to injury from environmental stresses and severe diseases and insect injury were also expected where thatch was excessively accumulated. Therefore, these results demonstrate that more frequent measures for controlling thatch such as vertical mowing, topdressing or coring should be employed for soccer fields with Korean lawngrass and KB over other turfgrasses.