• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1164-1168
• /
• 2011

This study evaluated the soil microbial communities by fatty acid methyl ester (FAME) method in soils (6 sites for immatured paddy, 9 sites for normal paddy, and 5 sites for sandy paddy) in Gyeongnam Province. The soil microbial biomass carbon content in normal and sandy paddy were 1,235 and $441mg\;kg^{-1}$, respectively, showing the soil microbial biomass carbon content in normal paddy was higher than that in sandy paddy. The soil organic matter contents $33g\;kg^{-1}$ of immatured and normal paddy were higher than sandy paddy $18g\;kg^{-1}$ (p<0.05). The communities of total bacteria and Gram-negative bacteria in normal paddy were significantly higher than those in sandy paddy (p<0.05). Total bacteria communities should be considered as a potential responsible factor for the obvious microbial community differentiation.

• Ecology and Resilient Infrastructure
• /
• v.4 no.4
• /
• pp.193-199
• /
• 2017

In this study, changes of soil properties including soil texture, specific surface area, organic matter content, pH, cation exchange capacity and exchangeable cations content were investigated in response to strong acid or base accident. The properties changed significantly when the soil reacted with 10 M HCl or 1 M NaOH (i.e., when one gram of soil received 50 and 5 mmol of HCl or NaOH), respectively. When the soil reacted with 10 M HCl or 1 M NaOH solution, soil texture changed from sandy loam to loamy sand and specific surface areas decreased from $5.84m^2/g$ to 4.85 and $1.92m^2/g$, respectively. The soil organic matter content was reduced from 3.23% to 0.96 and 0.44%, and the soil pH changed from 5.05 to 2.35 and 10.65, respectively. The cation exchange capacity decreased from 10.27 cmol/kg to 4.52 and 5.60 cmol/kg, respectively. Especially, high concentrations of $Al^{3+}$ or $Na^+$ were observed in acidic or basic spills, respectively, which is likely to cause toxicity to terrestrial organisms. The results suggest that restoration of soil properties, as well as soil remediation, needs to be carried out to maintain the soil function in chemical spill sites.

• Journal of Soil and Groundwater Environment
• /
• v.10 no.1
• /
• pp.13-17
• /
• 2005

Potential for measuring mobile cadmium concentration in sandy soil using polymer magnetic beads with carboxyl groups was investigated. Experiments for extracting cadmium were performed with contaminated soils, de-ionized water and magnetic beads. In this neutral experimental condition, reacting cadmium with magnetic beads indicate total amount of cadmium that can be moved in soil. The results showed that the mobile fraction of cadmium in soil could be combined with magnetic beads in short time. After binding between cadmium and magnetic beads, the beads were separated from soil suspension by outer magnetic force. The bound cadmium was dissolved from magnetic beads by acid solutions, which were then analyzed by atomic absorption spectroscopy (AAS). This method can determine mobile heavy metals in sandy soil effectively than existing method which use pollutant chemicals to environments such as EDTA.

• Journal of Plant Biology
• /
• v.20 no.1
• /
• pp.7-14
• /
• 1977

The seeds of bean(Glycine max M.) and corn(Zea mays L.) soaked in 5000ppm lead solution for 24 hours were sowed in the flowerpots being placed sandy-clay soil under the field condition. The fixed concentrations of various anions and 2000 ppm lead were supplied alternately in the sandy-clay soi of the flowerpots at two days interval from May to July in 1976. After the plants were harvested prior to the flowering stage, the lead contents of plnat and soil were analyzed by atomic absorption spectrophotometer. The lead contents absorbed by the plant roots showed the highest in an weak acid soil of the best suitable condition of plant growth. The absorption of lead by the plant roots was inhibited by the various anions, especially divalent anions of the soil. Some phosphate anions inhibited lead absorption more than otehr various anions in the soil. The more various anions were in the soil, the more plants could be protected from the lead toxicity. In the case of lead supply in the soil, 99.5% of lead was accumulated in the upper layer of the soil(0-10cm), and 0.5% of lead accumulated in the lower layer (10-20cm). Therefore, the yellow-brown and white symptoms on the leaves and the inhibition of root growth by lead toxicity was increased in the early stage of the germination, however decreased in accordance with the progress of the growing stage becuase of the root growth toward beneath the lower layer of the soil. In spite of the contents of 3773ppm lead in the soil, the symptoms of lead toxicity was not found in the grown plants. At that time the lead contents of the plants absorbed from the soil were minimum 0.78ppm and maximum 3.64ppm through the growing stage.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.5
• /
• pp.293-302
• /
• 2008

The limiting factors to determine available soil depth were studied with 390 soil series in soil profile description and physicochemical data in Korean soils. The limiting factors were coarse sandy layer, gravel and skeletal layer, hardpan layer, cat clay layer, poorly drained layer, salt accumulated layer and bed rock layer so on. The soils of having limiting factors were 332 soil series, but soils without limiting factors were 58 soil series. Soils with limiting factors were, hardpan 5, slopeness 93, immature soil 29, cinder 5, sandy 42, gravel or skeletal 47, bedrock 19, high salt content 8, poorly drained soil 22, heavy clay 32, sulfate soil 3 and ash soil 27 etc. And the orders of available soil depth were immature > slopeness > ash > heavy clay > sandy > gravel or skeletal > hardpan > cindery > poorly drained > bedrock > acid sulfate soil > salt accumulated soil etc.

• Korean Journal of Soil Science and Fertilizer
• /
• v.19 no.3
• /
• pp.239-244
• /
• 1986

This study was conducted to investigate the characteristics of humic substances and the fractional distribution of organic nitrogen in Korean paddy soils. The results are obtained as follows: 1. The content of humus in soils used was 665-2680 mg/100g and the average contents of humic acid in normal paddy soils and in sandy paddy soils were 1436 mg/100g, 970 mg/100g respectively. 2. The humic acid diagrams classed by Kumada method belong to B type, P type and Rp type. 3. The content of Mineral - N to Total - N was 1.04-2.86% and the average contents of that in sandy paddy soils and in normal paddy soils were 1.72% and 1.75% respectively. 4. The fractionations of acid hydrolysable organic - N in sandy paddy soils were Amino acid - N (31.52%), Humin - N (20.63%), Amino sugar - N (18.70%), and Unknown - N (25.73%).

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.2
• /
• pp.108-111
• /
• 2005

A field study was conducted to develop an economically suitable combination of organic and inorganic fertilizers for sugarcane cultivation in sandy acidic soil of a commercial sugarcane farm under Old Himalayan Piedmont Plain of Bangladesh. Results revealed that the treatment $T_4$ which received $75\%$ of Recommended fertilizers (N 120, P 35, K 100, S 25, Zn 2 kg $ha^{-1}$) + 10 Mg $ha^{-1}$ Rice mill ash + Mg $ha^{-1}$ press mud significantly produced higher sugarcane yield (72.34 Mg $ha^{-1}$) among all the treatments except $T_5$ having $100\%$ of Recommended fertilizers + 10 Mg $ha^{-1}$ Rice mill ash + 10 Mg $ha^{-1}$ press mud, which was identical. $T_4$ also gave the highest net economic benefit at Bangladesh Taka 15,920.47 per hectare from the added nutrient management. Thus, the integrated use with organic and inorganic fertilizer is highly essential for sustainable production of sugarcane in commercial farm of the region in Bangladesh, where it has been grown year after year.

• Korean Journal of Medicinal Crop Science
• /
• v.25 no.2
• /
• pp.102-107
• /
• 2017

Background: The present study was conducted to investigate the fatty acid content and habitat conditions of Glehnia littoralis in the Korean midwest region. Methods and Results: The emergence area of G. littoralis was 36.1 m from the coastline at an elevation of 4.2 m and slope of 4.3%. The soil of the habitat was sandy, the pH was 8.4, organic matter content was 0.4%, $P_2O_5$ content was 9.1 mg/kg and the content of K, Ca, Mg and Na were 0.09, 9.31, 0.43 and $0.23cmol^+/kg$, respectively. Other plants growing in this area with G. littoralis included 16 taxa. Plant with high coverage and frequency were Carex kobomugi, Elymus mollis, Imperata cylindrica var. koenigii, Lathyrus japonicus, Calystegia soldanella and Carex pumila. In the seeds of G. littoralis, the maximum fatty acid content was 65.5% oleic acid, 28.7% linoleic acid, 4.3% palmitic acid, 1.5% stearic acid, and 0.2% linolenic acid. Conclusions: In G. littoralis of Korean midwest, the scope of collection and cultivation for medicinal purposes was broad, because differences in associated vegetation, soil composition, and fatty acid content owing to habitat conditions was low.

• The Korean Journal of Ecology
• /
• v.12 no.2
• /
• pp.109-122
• /
• 1989

The vegetation and landscape of Hokkaido were phytosociologically referred. The region of F a g e t e a c r e n a t a e on Hokkaido is divided into two types of deciduous broad-leaved forest: the oak (Quercus mongolica var. grosseserrata) forests mixed with conifers (mainly Abies sachalinensis) and the beech (Fagus crenata) forests of northernmost distribution in far-east Asia. The oak forests, which is dominated by Quercus mongolica var. grosseserrata in Japanse islands, seem to be developed from different climatic and edaphic conditions, especially in the amount and sharing pattern of precipitation in a year, and weak acid brown forest soil, volcanic ash soil and sandy soil. On the all-inclusive phytogeographical view-point, Hokkaido is situated at northernmost region of F a g e t e a c r e n a t a e (cool-temperate zone)neighboring with subarctic and subalpine vegetation, vegetation, but the evergreen broad-leaved forest (C a m e l l i e t e a j a p o n i c a e, warm-temperate zone) is abscent.

• Journal of Soil and Groundwater Environment
• /
• v.18 no.1
• /
• pp.67-77
• /
• 2013

To improve the energy efficiency of conventional thermal treatment, soil remediation with microwave has been studied. In this study, the remediation efficiency of contaminated soil with semi-volatile organic contaminants were evaluated with microwave oven and several additives such as water, formic acid, iron powder, sodium hydroxide (NaOH) solution, and activated carbon. For the experiment, loamy sand and sandy loam collected from Imjin river flood plain were intentionally contaminated with hexachlorobenzene and phenanthrene, respectively. The contaminated soils were treated with microwave facility and the mass removals of organic contaminants from soils were evaluated. Among additives that were added to increase the remediation efficiency, activated carbon and NaOH solution were more effective than water, iron powder, and formic acid. When 10 g of hexachlorobenzene (142.4 mg/kg-soil) or phenanthrene (2,138.8 mg/kg-soil) contaminated soil that mixed with 0.5 g iron powder, 0.5 g activated carbon and 1 ml 6.25 M NaOH solution were treated with microwave for 3 minutes, more than 95% of contaminants were removed. The degradation of hexachlorobenzene during microwave treatments with additives was confirmed by the detection of pentachlorobenzene and tetrachlorobenzene. Naphthalene and phenol were also detected as degradation products of phenanthrene during microwave treatment with additives. The results showed that adding a suitable amount of additives for microwave treatments fairly increased the efficiency of removing semi-volatile soil organic contaminants.