• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.17-23
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• 2011

This research was conducted to investigate the influence of application rate of liming fertilizers on changes in soil chemical properties and growth of 'Red Madness' petunia in plug production. To achieve this, dolomite (DO) with 0, 1.0, 3.5, 8.0 or 13.0 $g{\cdot}L^{-1}$ and calcium carbonate (CC) with 0, 2.0, 2.5, 3.0, 3.5, or 4.0 $g{\cdot}L^{-1}$ were incorporated into peatmoss + vermiculite (1:1, v/v) during the root substrates formulation. The treatments of 3.5 $g{\cdot}L^{-1}$ of DO and 2.5 or 3.0 $gL^{-1}$ of CC had acceptable ranges of pH and EC in soil solution such as 5.6~6.2 and 0.7~1.0 $dS{\cdot}m^{-1}$, respectively. The faster rising of pH was observed in root media containing CC rather than those of DO. This indicates that the solubility of CC is higher than DO. The soil Ca concentrations in all treatments of CC were 1.8 times as high as those of DO. The treatments of 3.5 or 8.0 $g{\cdot}L^{-1}$ of DO had the highest soil Mg concentrations, but all treatments of CC had lower soil Mg concentrations than control treatment indicating that additional application of Mg fertilizers are required. The elevated application rate of DO or CC resulted in the increase of fresh and dry weight. But plant heights were not influenced by application of liming fertilizers. The results of tissue analysis showed that application of DO or CC influenced the $PO_4{^-}P$, Ca and Mg contents, but not influenced the contents of other nutrients such as N, P, Fe, Mn, Zn and Cu.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.595-604
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• 2015

Soil chemical properties in paddy fields were found to be varied depending upon different cultivation methods such as environmentally-friendly, conventional, and two-crop farming systems and different topographical regions, namely plain, middle mountainous, and reclaimed land regions. Overall soil pH was found to be in optimal range (pH 5.5~6.5) for rice cultivation, except with conventional cultivation fields of the reclaimed lands in Jeonnam province. Electrical conductivity (EC) was relatively higher in the two-crop cultivation fields than in others. However, the concentrations of available phosphate as $P_2O_5$ were exceptionally higher in the two-crop farming fields, thus in submerged paddy condition the phosphate could be released into streams and rivers. Soil organic matter (SOM) contents were mostly in optimal range ($25{\sim}30g\;kg^{-1}$) for paddy field in Jeonbuk province, but in Jeonnam province they were slightly higher values of the range. The concentrations of available silicate ($SiO_2$) were mostly depended on the cultivation methods and the region, but some of paddy fields contained extremely high $SiO_2$ concentration. Statistical relationships among the soil chemical properties showed as follows: Correlations between EC values and exchangeable cation concentrations, between SOM contents and CEC values, and between available $SiO_2$ concentrations and pH, EC, exchangeable cations, and CEC values were positively significant, whereas total nitrogen concentrations were significantly negatively correlated with the concentrations of exchangeable K and Mg. These results might be very useful to establish benchmark paddy fields contained with certain levels of soil fertility.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.4
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• pp.67-73
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• 2009

Chemical properties of soil in the proposed horticultural complexes of Saemangeun reclaimed tideland were studied for sustainable development of the newly reclaimed land resources. The soil texture of Gwanghwal, Gyehwa, Mangyeong and Okgu complex area were sandy loam. The pH and ESP (exchangeable sodium percentage) were 7.42 to 7.82 and 61.05 to 73.62 %, respectively. Compared to general agricultural land in Korea, the soil organic matter and other plant nutrients were low. The concentrations of heavy metals in the soil were found to be acceptable except several sites where they doesn't meet the warning standard of agricultural land contamination. Continuous monitoring and interception of external pollutants are suggested for water-soil-plant system conservation.

• Journal of Soil and Groundwater Environment
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• v.25 no.1
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• pp.74-83
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• 2020

In this study, the effect of hydrochloric acid (HCl) concentrations on removal efficiency and chemical forms of heavy metals in dredged sediment during acid washing was investigated. The removal efficiencies of Zn, Cu, Pb, Ni and Cd by acid washing were 18.4-92.4%, 7.2-83.7%, 9.4-75%, 8.1-53.4% and 34.4-70.8%, respectively. Overall, the removal efficiencies of heavy metals were remarkably enhanced with the increase of the acid strength. However, the removal efficiencies for 0.5 and 1.0 M HCl were comparable, and both cases met the Korean soil contamination standard. Based on the sequential extraction results, concentration of the exchangeable fraction (F1), the most labile fraction, increased whereas concentrations of the other fractions decreased with increasing acid strength. Particularly, the carbonate (F2) and Fe/Mn oxides (F3) fractions drastically decreased by using 0.5 M or 1.0 M HCl. The current study results verified that acid washing could effectively reduce heavy metal concentrations and its potential mobility in dredged sediments. However, the study also found that acid washing may cause significant increase in bioavailable fraction of heavy metals, suggesting the need to evaluate the changes in chemical forms of heavy metals by acid washing when determining the acid strength to be applied.

• Journal of Environmental Science International
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• v.24 no.2
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• pp.175-188
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• 2015

For 63 soil series distributed in Jeju Island, natural uncultivated soils in each soil series were collected, and their physicochemical properties and their concentrations of 19 heavy metals including 8 heavy metals which are regulated by Korean Soil Environment Conservation Law, were analyzed. Moreover, the correlations between physicochemical properties and heavy metal concentrations, and between heavy metal concentrations were analyzed. The heavy metals distributed in the higher concentrations and the lower concentrations with arithmetric mean value, were Mn(730 mg/kg) and Ba(493 mg/kg), and Hg(0.146 mg/kg) and Tl(0.096 mg/kg), respectively. The correlations between pH($H_2O$) and heavy metals(Hg, Ni, Co, Se), between pH(NaF) and heavy metals(Hg, Ba, Se, Tl), and between organic matter content and heavy metals(Hg, Tl) were significant at the 0.01 level. From the correlations between heavy metal concentrations, there were 22 where there were significant at the 0.01 level and they showed positive correlation. Among those, the heavy metals showing the correlation higher than r=0.5, were Sb-V(0.878), Mo-Sn(0.867), Co-V(0.654), Co-Sb(0.648), Be-Sn(0.546), and Sn-Tl(0.528).

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.242-247
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• 2011

Soil management for environment-friendly agriculture depends on the effects of soil microbial activities and soil fertility. To improve soil health for the upland crops, this study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in upland soils in Gyeongnam Province. The average nutrients in the upland soils were 1.7 times for available phosphorous, 1.4 times for exchangeable potassium and 1.5 times for exchangeable calcium higher compared to recommend concentrations in the upland soils. We found a significant positive correlation between the soil organic matter and the soil microbial biomass C (p<0.01). Contents of organic matter and dehydrogenase in the inclined piedmont soils were significantly higher than those in the other topographical soils (p<0.05). In addition, concentrations of organic matter and microbial biomass C in the loam soils were significantly higher than in the silt loam soils (p<0.05). In principal component analyses of chemical properties and microbial populations in the upland soils, our findings suggested that available phosphorous should be considered as potential factor responsible for the clear upland soils differentiation. The soil organic matter was positive correlation with Bacillus sp. and fungi, whereas soil pH was also positive correlation with Pseudomonas sp. in upland soils.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.315-322
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• 2011

We investigated the effect of Pb uptake by Pinus densiflora and the Pb fraction in forest soil. We also investigated the change in soil physicochemical characteristics, microbial activity, and root exudates of Pinus densiflora in Pb-contaminated soils. Three-year-old pine seedlings were exposed to 500 mg/kg Pb for 12 months. The metal fractions were measured using sequential extraction procedures. Additionally, factors that affect solubility (three soil enzyme activities and amino acids of root exudate compounds) were also determined. The results showed that Pb contamination significantly decreased enzyme activities due to soil characteristics. In addition, organic matter, nitrate content, and Pb concentration were time dependent. The results indicate that changes in the Pb fraction affected Pb uptake by pine trees due to an increase in the exchangeable Pb fraction. The concentrations of organic acids were higher in Pb-spiked soil than those in control soil. Higher rhizosphere concentrations of oxalic acid resulted in increased Pb uptake from the soil. These results suggest that pine trees can change soil properties using root exudates due to differences in the metal fraction.

• Journal of Ecology and Environment
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• v.33 no.1
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• pp.15-18
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• 2010

Mangroves are special plant communities that live along intertidal zones in tropical and subtropical areas. They are regarded as one of the most important types of natural ecosystem in the world because of the many ecosystem functions that they perform, of which water purification is the most complex. Mangrove ecosystems are conducive to the deposition and retention of heavy metals. So it is important to understand the impact of heavy metals on mangrove ecosystems, and especially on soil subsystems. We examined the levels of heavy metals in the soil of mangroves in the Dongzhaigang Mangrove National Nature Reserve. Dongzhaigang, the first mangrove nature reserve established in China, is located south of Haikou in Hainan Island and encompasses $33.37\;km^2$, of which mangroves comprise $20.56\;km^2$. To assess the impact of human activities, we collected a large number of soil samples in four sampling areas (the protection station, the harbor, a tour area, and Yeboluo island) in the study area. We measured the concentrations of Cu, Pb, Zn and Cd in the soil samples using the spectra of polyatomic molecules. The average concentrations of Cu, Pb, Zn and Cd were $5.04\;{\mu}g/g$, $10.36\;{\mu}g/g$, $20.06\;{\mu}g/g$ and $0.06\;{\mu}g/g$, respectively, and the heavy metal concentrations were lowest in the protected area, highest in the harbor, and intermediate in Yeboluo Island and the tour area. The heavy metal concentrations in the soil collected from different sample plots are related not only to the physical and chemical properties of the soil, but also to the heavy metal emitted by nearby pollution sources. Our analysis indicates that tourist boats are the main pollution sources in the study area.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3651-3656
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• 2012

The size-segregated atmospheric aerosols have been collected at 1100 m site of Mt. Halla in Jeju, a background area in Korea, using 8-stage cascade impact air sampler during Asian dust and non-Asian dust storm periods. Their ionic and elemental species were analyzed, in order to examine the pollution characteristics and composition change between Asian dust and non-Asian dust periods. The major ionic species such as nss-$SO_4{^{2-}}$, $NH_4{^+}$, and $K^+$ were predominantly distributed in the fine particles (below $2.1{\mu}m$ diameter), and besides the $NO_3{^-}$ was distributed more in coarse particle fraction than fine particle. On the other hand, the typical soil and marine species i.e., nss-$Ca^{2+}$, $Na^+$, $Cl^-$, and $Mg^{2+}$, were mostly existed in the coarse particles (over $2.1{\mu}m$ diameter). As well in the elemental analysis of aerosols, the major soil-originated Al, Fe, Ca, and others showed prominently high concentrations in the coarse particle fraction, whereas the anthropogenic S and Pb were relatively high in the fine particle fraction. From the comparison of aerosol compositions between Asian dust and non-Asian dust periods, the concentrations of the soil-originated species such as nss-$Ca^{2+}$, Al, Ca, Fe, Ti, Mn, Ba, Sr have increased as 2.7-4.2 times during the Asian dust periods. Meanwhile the concentrations of nss-$SO_4{^{2-}}$ and $NO_3{^-}$ have increased as 1.4 and 2.0 times, and on the contrary $NH_4{^+}$ concentrations have a little bit decreased during the Asian dust periods. Especially the concentrations of both soil-originated ionic and elemental species increased noticeably in the coarse particle mode during the dust storm periods.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.500-505
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• 2014

In recent years, organic ginseng cultivation has increased because customers prefer organic ginseng products due to the morphological quality as well as the safety such as the residuals of chemically-synthesized pesticides. Therefore, some of paddy and upland fields were converted into organic ginseng fields. Soil chemical properties, soil microflora, and soil-inhabiting animals were investigated in paddy-converted and upland organic ginseng fields in Sangju city, Korea. There was few difference in the soil chemical properties, and the soil nutrient concentrations, such as nitrate-N, Av. $P_2O_5$ between the two field types, and exchangeable cations such as K and Ca were within the ranges which are recommended by the standard ginseng-farming manual. Changes in microflora were also assessed by analyzing phospholipid fatty acid composition. Overall, indicators of microbial groups were greater in the upland field than in the paddy-converted soil, but they were not significantly different. In addition, there was no significant change in the abundance of nematodes, collembolans, and mites between the two field types probably because of the high variation within the field types. In this study, it was suggested that soil chemical and biological properties for organic ginseng cultivation were greatly influenced by the variation of topography and soil management practices rather than field types. Further study may be needed to investigate the influence of these factors on soil chemical and biological properties in organic ginseng soils.