• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.509-516
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• 2010

This study investigates characteristics of diesel degradation and variations of microbial community with the soil enrichment cultures. The cultures has yellow(YE-5) and transparent color's(WH-5) colony on solid plate medium. The bacillus type of YE-5 and WH-5 cultures showed diesel degradation at the rate of 99.07mg-Diesel/$L{\cdot}day$ and 57.82mg-Diesel/$L{\cdot}day$ in the presence of 1%(v/v) initial diesel concentration. Diesel degradation was 1.7 times faster than WH-5 culture. YE-5 or WH-5 culture could degrade a wide range of diesel compounds from $C_8$ to $C_24$. Microbial community analysis by PCR-DGGE technique shows that Psedomonas, Klebsiella, Escherichia and Stenotrophomonas as proteobacteria take role on the diesel degradation. uncultured Senotrophomonas sp. was only detected with YE-5 culture. It is concluded that proper combination of the microorganism should be present to stimulate the degradation of diesel and further studies are recommended for the effect of uncultured Senotrophomonas sp. or Escherichia hermannii on diesel degradation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.206-214
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• 2011

Fifteen clones of poplars, 2 clones of willows, and yellow poplar were used to evaluate the effects of 5 treatments such as SCBLF (slurry composting and biofiltration liquid fertilizer), general slurry liquid fertilizer, chemical fertilizer, groundwater, and control (no treatment) on vitality, growth performance, and biomass production. Five cuttings for each tree species were planted in 3 replications. After planting cuttings, a coppice was induced by cutting off stems at 10cm above the ground. Data were collected for first growing season and trees were harvested at the end of October. Maximum mortality rate i.e. 96% was recorded in the cuttings treated with groundwater and minimum 92% with control (no treatment). In all tree species, sprouting of stump was not differ significantly among the treatments. Total nitrogen concentrations of leaves and stump sprouts were higher in the treatment of SCBLF than the control, 26.6% and 22.9%, respectively. Biomass production was highest in the stumps treated with chemical fertilizer, $1.98Mg\;ha^{-1}\;year^{-1}$, and lowest in control ($1.34Mg\;ha^{-1}\;year^{-1}$).

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.480-490
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• 2001

The soil-air exchange processes of Hg were investigated from the Hari area of Kang Hwa Island during the late March 2001. In the course of our study, we determined the concentration gradients of Hg and combined these gradient data with micrometeorological components to derive its fluxes. Results of our study indicate that the concentration levels of Hg in the study area are notably lower than those typically found in urbanized areas of Korea. However, the computed fluxes were seen to be significantly larger for relatively remote areas, reaching over 200 ng/m$^2$/hr. Comparison of environmental conditions shows that the concentrations of most pollutant species including NO$_X$ and PM were significantly higher during emission, while meteorological conditions were characterized by high temperature and low humidity. Results of correlation analysis also indicate that such pollutants as hydrocarbons, nitrogen oxides, and PM generally exhibit strong positive correlations with Hg-related parameters during emission events, while such relationships were reversed during dry deposition events. The results of our present study suggest the possibility that the concentrations and fluxes of total gaseous Hg observed during deposition events can be influenced by the processes that are also important for the fine, rather than coarse, size fraction of particles.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.365-371
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• 2007

Objective of this research was to investigate the effect of nitrogen concentrations in the fertilizer solution on growth and development of nutrient deficiency in leaf perilla (Perilla frutesens). The nutrient concentrations in above-ground plant tissue, petiole sap and soil solution of root media were also determined. Nitrogen deficiency resulted in dwarfed growth, small leaves, and bright yellow color of older leaves. The leaves of deficient plants became uniform yellowing in color and finally necrosis occurred on the deficient leaves. Elevation of N concentrations in the fertigation solution from 0 to 20 mM increased the crop growth in leaf length and width as well as fresh and dry weights of above ground plant tissue. That also resulted in the increase of chlorophyll contents. However, light toxicity symptoms such as abnormal leaf surface appeared on crops grown in 20 mM N fertilization. The plant growth was commercially acceptable in the treatments of 10 and 15 mM N. The plants with acceptable growth had 0.9 to 1.25% in N contents of above-ground plant tissue, 800 to $3,300mg{\cdot}kg^{-1}$ in the $NO_3-N$ concentrations of petiole sap, and 28.7 to $47.3mg{\cdot}kg^{-1}$ in the $NO_3-N$ concentrations of soil solution (1:2 extract) at 75 days after transplanting.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.263-271
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• 2013

A xylanase-producing bacterium was isolated from a soil sample collected in Yongin city, Korea. The strain was aerobic and gram positive, and grew between pH 5.0 and 11.0, forming a yellow-colored colony. The strain was classified as a novel subspecies bacterium of Paenibacillus barcinonensis by 16S rRNA gene sequence similarity, phylogenetic analysis, phenotypic, and biochemical characteristics, and thus named Paenibacillus sp. HX-1. This strain produced extracellular endo-${\beta}$-1,4-xylanase, and the best xylanolytic activity (205.17 unit/ml) was obtained at 96 h in an optimized TNX medium containing 1% (w/v) bacto tryptone, 1% (w/v) NaCl, and 0.7% (w/v) beechwood xylan at pH 7.0, $37^{\circ}C$ and 200 rpm. The endo-${\beta}$-1,4-xylanase produced by the strain HX-1 yielded xylobiose as the end product from beechwood xylan hydrolysis. The enzyme exhibited optimum pH and temperature at pH 7.0 and $45^{\circ}C$, respectively. The remarkable enhancing effect of the TNX medium on xylanase production by HX-1, in spite of its simple formula, may have great advantages for industrial applications of xylanase.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.61-70
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• 2007

This study was conducted to investigate nutrient dynamics and water quantity of throughfall and stemflow in natural oak stands in Korea. The ratio of the total throughfnll and stemflow to the amount of precipitation varied with locations. It was considered that the ratio was affected not only by the characteristics of tree species but also by regional, weather and other environmental conditions. It was, therefore, necessary to set up a water control system to launch a tending project for natural oak stands. Comparisons of nutrient amount in throughfall among regions reflected regional characteristics. $Ca^{2+},\;Mg^{2+}$ and $K^+$ ions were leached from the canopy and yellow sand accumulation. $Na^+$ and $Cl^-$ were marine-borne. $NO_3^-$ and $SO_4^{2-}$ resulted from dry deposition of air pollutants. Nutrient amount in the stemflow was as low as about 10% of that in the total throughfall and stemflow. The pH of stemflow in natural oak stands in urban areas ranged from 3 to 5. Influx of the acidic stemflow to soil could, in the long term, affect pH in soil solution and nutrient dynamics around root zones.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.29-36
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• 1996

This experiment was conducted to investigate the effects of the application of complete fertilizer on the yields and quality of leaf tobaccod grown in soils with different fertility levels. The contents of inorganic nitrogen, organic matter and available phosphorus in the soil with high fertility level were shown to be more than those in the soils with medium and low fertility levels of the experimental fields. The contents of total nitrogen, nicotine and reducing sugar in the tobacco leaf were more than those in the cutters tobacco. The contents of total nitrogen and nicotine in the leaf tobacco increased as the application amounts of the fertilizer(10:10:20) increased, however, the reducing sugar contents in the leaf tobacco decreased. The increase in the yields of leaf tobacco was detected at the application amount of 75kg/10a in soils with high fertility level, but for high yield of leaf tobacco in the soils with low and medium levels the application amount of the fertilizer was found to be over 100kg per 10a. The quality (price/kg or price/kg ${\times}$ yield) of the leaf tobacco was known to be excellent at 50~75kg/10a of the application amount of the fertilizer(10:10:20) in soil with high fertility level and over 100kg/10a in the other soils in the experiment.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.273-282
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• 2023

Hypochaeris radicata, native to Europe and Eurasia, is a perennial plant of the Asteraceae family. In Korea, H. radicata was reported in 1992, mainly in Jeju Island, and gradually spreading to the inland. It overwinters in the form of a rosette and blooms yellow flowers from May to June. H. radicata propagates by seeds and rhizomes. The germination temperature of the seed is 15/20℃ (day/night), and the rhizome forms a new plant at a depth of 2-3cm in the soil. The roots of H. radicata secrete allelochemicals that inhibit the development of other plants. Some use it as a salad or forage substitute but to a limited extent. However, extensive research on ampicillin contained in H. radicata has been conducted, and its anticancer and anti-inflammatory effects have been recognized. There are only a few methods to manage H. radicata both culturally and physically. In orchards, soil treatments such as oxyfluorfen and diclobenil, or nonselective foliar treatments such as glufosinate-ammonium and glyphosate are used. Notably, there are no known biological control agents.

• Research in Plant Disease
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• v.16 no.2
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• pp.115-120
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• 2010

In this study, changes in virus disease occurrence and yield were monitored in conventional cropping system(rice-barley) and soybean-barley double cropping system in virus-prone area for 5 years. Also, changes in the density of Polymyxa graminis, a fungal vector, was investigated. In assay tests, mixed infection of Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) was observed. Disease severity was in the range of 7~9 in conventional cropping system. In continuous cropping of soybean-barley and 3-yearfallow land, disease severity also was around 7. However, disease severity was reduced to medium level (5) when barley cultivation was paused for one or two years in soybean-barley cropping. When barley cultivation was paused for a year, the density of P. graminis, a fungal vector for BaYMV and BaMMV, reduced in barley root and soil. Similarly, barley growth was also enhanced by adopting fallow seasons. Compared with the fifth year of conventional cropping, the number of tillers per $m^2$ was increased by 158 when barley cultivation was paused for an year in soybean-barley cropping. When soybean and barley were cultivated continuously or complete fallow period was extended to three years, plant height and the number of tillers of barley were decreased. Yield components of barley in soybean-barley cropping were superior to those in rice-barley cropping. Compared with the fifth year of conventional cropping and soybean-barley cropping, culm length of barley was 1.3~2.3 cm higher and the number of tillers per $m^2$ was 36~90 higher when barley cultivation was paused for one or two years. However, those in continuous cropping of soybean-barley and 3-year-fallow land were lower compared with conventional cropping. Similarly, yield was increased when barley cultivation was paused for one or two years in the third, forth, and fifth years when compared with conventional cropping.

• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.161-170
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• 2008

Recently irregular dark-colored patches were found on the Kentucky teeing ground in a golf course in Gyunggi providence. Interestingly, blue-green algae from the leaf tissue sample containing black spot-stained symptoms were largely observed through microscopic study. In general, algae present on the upper soil surface or in the upper layer of root zone form dark brown layers of scum or crust, which invoked harmful effects to turf growth such as poor drainage, inhibition of new root development. In this observation, unlike the algae were sometime found in senescing leaves on contacted soil in July and August, the blue-green algae were detected within black spot-stained Kentucky bluegrass leaf tissues including leaf blade, ligule, auriclea as well as leaf sheath. The blue-green algae were also detected on the leaf and stem tissue adjacent to the symptomatic leaf tissues. Two species of blue-green algae, Phomidium and Oscillatoria, were greatly observed. Oscillatoria species was more commonly notified in all samples. In addition, the two species were found on a putting green showing yellow spot disease at another golf course in Gyunggi providence. The data from chemical control assay revealed that chemicals such as propiconazole, iprodione, and azoxystrobin decreased blue-green algae population and leaf spots, which finally resulted in enhanced leaf quality. All taken together, we strongly suggested that the disease-like phenomenon by blue-green algae might be very closely mediated with infection/translocation process in relation with turfgrass. It indicates that blue-green algae in turf management may play an adverse role as a secondary barrier as well as a pathogenic agent. This report may be helpful for superintendents to recognize and understand the fact that algae control should be provided more cautiously and seriously than we did previously in upcoming golf course management.