• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.275-282
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• 1986

A series of studies on the properties of clayey terrace soils distributed at the inland (Yeongcheon) and coastal (Yeongjil) regions in Yeongnam district was carried out. On the base of the facts found and already reported about the macro morphological features as well as on pedological characters in micro scale, physicochemical properties, mineralogical characteristics etc., the present study dealt with soil genesis and tried to classify the soils for reasonable use and managements. 1. Although the both regions belonged to "Mesic" soil temperature regime and "red and yellow earths" areas of "Thornthwaite" pedo-climatic diagram, climatic indices as a soil forming factor indicate that the coastal Yeongil had milder than the inland Yeongcheon. 2. All the terrace soils had developed soil profiles with an "Argrllic B". Upyeong soils in Yeongil region had "Argillans" even in the "II B horizons" that possibly be "Paleo-argillic". 3. The bisequum profiles of Bancheon in Yeongcheon and Upyeong in Yeongil revealed that they were developed on Late Mesozoic shale and on semiconsolidated Tertiary deposits respectively, therefore the overlying clayey terrace deposits were assumed to be originated from the Early Quaternary deposits, Diluvium. 4. To supplement the Soil Taxonomy of USDA, the terrace soils with different degrees of gleyzation were classified as follows; Deogpyeong and Hwadong soils which have less than 50cm of paddified gley horizons (redness less than 0.5) in the upper part of the profiles by artificial surface irrigation, tentatively classified into "Anthrepiaquic Hapludalfs" and the Geugrag soils that have more than 50cm of paddified gley horizons within 1.2m of the profiles, into "Anthr-aquic Ochraqualfs" while the Upyeong soils that had greyish mottles in subsoils by natural ground water remain as an "Aquic Hapludalfs" the same as present. The Bancheon soils with free mottles are into "Typic Hapludalfs" as used at present.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.171-181
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• 1999

A field experiments was carried out to investigate the physicochemical properties of soil and cucumber growth in vinyl house when irrigation point was made at 0.2, 1/3, 0.5 and 1.0 bar. The obtained results was summarized as follow: The taxonomic class of the soil used was loam and each content of the required water was 4.4, 7.3, 9.6 and 13.4 mm per each irrigation time at 0.2, 1/3, 0.5 and 1.0 bar treatments in spring culture, respectively. At 0.2 bar and 1.0 bar treatments, interval of irrigation was 2.3 and 14.8 day, the times of irrigation was 37 and 6, and total irrigation volume was 163.5 and 80.3 mm, respectively. After cucumber culture, pH, EC concentration and exchangeable K content of soil at 0.2 bar treatment was distributed near to the level of improvement target while EC, available $P_2O_5$ and exchangeable base content in other treatments were higher compared to improvement target. At 1.0 bar treatment, ratios of the solid and liquid phase were 44.9 and 27.1%, respectively, and bulk density was $1.26g\;cm^{-3}$ which was the highest among the treatments. At 0.2 bar treatment, the ratio of the solid and liquid phase was 41.7 and 22.8%, respectively, and bulk density was $1.09g\;cm^{-3}$ which was the lowest. The root length and radius at 0.2 bar treatment were best, while those at 1/3 bar were worst. At 0.2 bar treatment, the total yield was 7,269 kg and the weight of good products was 5,677 kg which was the highest among treatments. At 0.33 bar treatment, the yield was the lowest with the high ratio of deformity.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.4
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• pp.288-294
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• 2012

The current growth of nano-industries has resulted in released nanoparticles entering into water and soil ecosystems via various direct or indirect routes. Physicochemical properties of nanoparticles differ from bulk materials, and nanomaterials influence the fates of nanoparticles and the interactions of living or non-living things in the environment. Microcosm analysis is a research methodology for revealing natural phenomena by mimicking part of an ecosystem under controlled conditions. Microcosm study allows for the integrated analysis of toxic effects and fates of nanoparticles in the ecosystem. Ecotoxicity studies of nanomaterials are steadily increasing, and microcosm studies of nanomaterials are currently beginning to surface. In this study, microcosm studies of nanomaterials in water and soil ecosystems were extensively investigated based on SCI(E) papers. We found that the microcosm studies have been reported in 12 instances, and mesocosm studies have been reported in only once until now. Advanced research was mostly evaluated at the microorganism level. But integrated analysis of nanotoxicity is required to research the interactions based of various species. Thus, our studies analysed the trend of microcosm studies on nanomaterials in water and soil ecosystems and suggested future directions of microcosm research of nanomaterials.

• Journal of Mushroom
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• v.16 no.3
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• pp.231-235
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• 2018

Arthrographis cuboidea is a wood rot fungus found in soil. It causes disease in repeated cultivation areas of Ganoderma lucidum, which damage the mushroom logs and causes considerable loss of income to mushroom farmers. This study aimed to investigate the physicochemical properties of soil and characteristics of the growth environment such as the temperature of the Ganoderma lucidum cultivated land. The time required for primordia initiation was 12-13 days. In the chromaticity survey, the degree of redness (a) was 19.5 for vinyl, 20.2 for control, and 19.5 for nonwoven. The yellowness index (b) was 12.7 for vinyl, 13.3 for control, and 12.4 for nonwoven. In the study of growth characteristics, in case of no treatment (control), the length and thickness of the pileus were measured as 145.7 mm and 23.6 mm and those of the stipe were 73.9 mm and 11.5 mm, respectively, and the weight was 130 g. Treatment with non-woven fabric resulted in 157 mm and 93.3 mm long and 22.3 mm and 11.9 mm thick pileus and stipe, respectively, and the weight was 164 g. This result indicates that treatment with non-woven fabric is better than no treatment with respect to Ganoderma lucidum growth.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.134-144
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• 2001

This study was conducted to investigate physicochemical and microbiological properties during composting process when pig manure was composted with some bulking agents(Saw dust, Rice hull, Crushed wood). The pig manure consisted of 2.95% total nitrogen, 4.55% $P_2O_5$, 2.07% $K_2O$, 81.2% organic matter and 14.0 C/N, dry base. The inorganic content of bulking agents were similar one another, and C/N ratio was Saw dust 392. Rice hull 91.5, Crushed wood 266. The temperature of Saw dust composting slowly increased at initial stage, whereas one of Rice hull and Crushed wood rapidly increased and stabilized similarly to outdoor temperature after about 2 month. The pH of compost increased during initial 1 month after decreasing, but thereafter decreased rapidly. The C/N ratio rapidly decreased at initial stage, and it slowly decreased after 1 month. Total nitrogen somewhat increased according to composting process. Ammonium-nitrogen increased until 60th day, and thereafter it was rapidly inclined to decrease. The population of aerobic bacteria, Bacillus spp., actinomycetes and fungi increased up to > $10^{10}cfu\;g^{-1}$ fresh weight, > $10^7$, > $10^8$ and > $10^6$, respectively in Rice hull and Crushed wood composting, and more than ones in Saw dust composting, and specially actinomycetes. The persuasive Bacillus spp. isolated from composting process were B. lentimorbus, B. licheniformis, B. pumilus, B. megaterium, etc.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.207-212
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• 2012

The objective of the present study is to identify the physico-chemical characteristics of used plug media (UPM) and its effect on growth response of tomato and cucumber seedlings. The UPM from commercial media Mix#5 (Sungro co., Ltd.) was used in this study. This media was sterilized by sterilizer at $120^{\circ}C$ in 30 minutes at 1.5 atm. Physicochemical properties of UPM was compared with new plug media (NPM). Physical properties such as air volume, particle density, solid volume, bulk density were investigated by three phase device (DIK-1130, Japan). And chemical characteristics such as $NO_3$-N, $P_2O_5$, K, Mg, Ca, $SiO_2$, CEC, OM were investigated by soil spectrophotometer (PTIZEN 1412SA, Mecasys Co., Ltd). The result indicates that air volume and water holding capacity of UPM are lower than NPM (25%, 15%, respectively). Bulk density and soil weight are more than two times higher than NPM per unit volume. Compared to NPM, there were no significant different for pH and EC. But CEC of UPM is lower than NPM 40%. In order to compare growth response and ability absorption of inorganic elements by plants, cucumber and tomato seedlings were used and chemical characteristics after growing of mediums were determined. The result indicated that seeding quality of tomato and cucumber in UPM is less than in NPM and almost inorganic ions of UPM are lower than NPM. So it is necessary to improve physicochemical properties of UPM.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.352-360
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• 2002

This study was carried out to find out the effect of Milk vetch(Astragalus sinicus L.) on growth, and yield of rice, physicochemical properties of soil, reduction rate of nitrogen fertilization, and soil improvement under the different plowing time with Milk vetch cultivated in paddy field, plowing at maximum blooming, last blooming, fruiting stages. The fresh weight of Milk vetch at each plowing time of maximum blooming, last blooming and fruiting stage was 22,500, 20,000, $12,500kg\;ha^{-1}$ respectively. Content of total nitrogen at three plowing times was 2.95, 2.66, and 2.47% and the C/N ratio were 15.7, 18.0, and 19.2, respectively. Physico-chemical properties of soil were improved in cultivated milk vetch, the content of T-N. OM and porosity ratio were increased while the content of $P_2O_5$ and bulk density, solidphase ratio were decreased compared to noncultivated milk vetch. Content of $NH_4-N$ in soil was highest plowing at maximum blooming stage and appeared an increasing tendency according to increased nitrogen level. Amount of nitrogen fertilizer by rice was highest plowing at maximum blooming stage and appeared an increasing tendency according to increased nitrogen level. Nitrogen-use efficiency was high in $33kg\;ha^{-1}$ nitrogen level at three plowing times. The number of spikelets per $m^2$ was high in plowing at maximum blooming stage, last blooming stage and the percentage of ripeness was high in fruiting stage of milk vetch. So the rice yield was increased 9%, 8% in $55kg\;ha^{-1}$ nitrogen level plowing at maximum blooming stage, last blooming stage and 1% in $77kg\;ha^{-1}$ nitrogen level plowing at fruiting stage compared to conventional cultivation.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.103-108
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• 2001

The objectives of this study were to investigate the contamination of the soils around the major roadsides in Seoul and to accumulate base-line data. Fifty topsoils ($0{\sim}5$ cm) and 48 subsoils ($20{\sim}50$ cm) were collected from 50 sampling sites near Manguro in Chungnanggu. The samples were air-dried, passed through 2-mm sieves, and analyzed to determine the physicochemical properties and the contents of heavy metals (Cd, Cu, Pb, Zn) and anions (Cl, $NO_3$, $SO_4$). Soil textures of top- and subsoils were mainly loamy sand and sandy loam, respectively. Average $_PH$ of top- and subsoil was approximately 7.5, much higher than that of the forest soils in Seoul. Average heavy metal contents were lower than the levels allowed by the Soil Environment Conservation Act of Korea, whereas much higher than those of the forest soils. Contents of some heavy metals were higher than the maximum allowed levels. Anion concentrations were also much higher than those of the forest soils. A careful management to prevent the aggravation of the present contamination level and the diffusion of contaminants is recommended.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.68-76
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• 2010

In the green house, the effect of the mixed material of vermicast and humic acid on the growth of young raddish was investigated. 5, 10, 15, 30 or 50 kg(a.i.) of solid type humic acid was mixed with 300kg(d.w.) of vermicast/10a, each of which was applicated to the soil. And the conventional treatment(600kg of conventional organic fertilizer/10a) and untreatment plot were rendered for comparison. In all the experimental plots treated with vermicast, the number of leaves, leaf length, leaf biomass, root length, root diameter, root biomass of young raddish were higher than those in untreated plot. And in the experimental plots treated with the mixed materials of vermicast and humic acid, growth rate of young raddish was equal to or higher than that in the conventionally treated plot. Fresh biomass of leaves per leol' raddish in the plot treated with 300kg of vermicast + 5kg of humic acid was 1.79 times higher than that in the untreated plot and fresh biomass of root was 2.08 times higher, which was much more effective in its growth rate than that in any other treated plots. There were no prominent changes in soil physicochemical properties after the leol' raddish harvest from the soil treated with vermicast and humic acid, though.