• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.501-511
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• 2011

This study was carried out to evaluate the effect of applying levels of Bestamin, animal amino acid, on growth and quality of hot pepper and physicochemical properties of soil. Treatment was given with 200, 400, 800, 1600kg per 10a to control of Bestamin, difference of physicochemical properties was lower than Bestamin, and $P_2O_5$ seems to be reduced, also $K^+$, $Ca^{++}$ were obviously low compared to the control. The content of $NO_{3-}N$ was low compared to control at the Bestamin treated plot. Plant height was longest at 800 treatment and main stem length, main stem weigh and the number of leaves were significantly different with 400 and 800 treatment. No difference was found among the fruit weight, length, diameter in first harvest, but there was significantly different at control of 2nd, 3rd harvest and more increased than 400 and 800 treatment. Fruit weight per plant was the heaviest at 400 and 800 treatment, and the number of fruit was no difference at red pepper but increased with 400 and 800 at green pepper, and yield per 10a was significantly increased to 4503.6kg and 4582.5kg, respectively. Nitrogen in mesophyll accumulation content was obviously reduced at Bestamin treatment compared to control, and amino acid was reduced with control.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.230-238
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• 1998

This study was conducted to compare the regeneration of the seedlings under different vegetation types and to identify the presence of allelopathy in Abies koreana(Ak) natural forest in Banyabong Peak(elevation, 1715m), of Mt. Chiri. Twenty quadrats($10m{\times}10m$) were placed in May, 1996 to classify vegetation structure using TWINSPAN. Water-soluble extracts from leaves and soil humus of different vegetation types were collected to test their effects on both seed germination of Ak and mycelial growth of ectomycorrhizal fungi. Phenolic compounds from soil humus were quantified using HPLC. Among the four vegetation types, Sasa borealis(Sb) was found in both Ak-Quercus mongolica(Qm) and Ak-Rhododendron schlippenbachii(Rs) communities. Natural seeding of Ak was $230,000{\pm}90,000seeds/ha$ in 1995 and their germination rate was 25% in an ideal laboratory condition. Density of Ak seedlings less than 5cm in height was 52,000/ha in 1996, while that of seedlings taller than 5cm in height was only 4,000/ha. In the case of Ak-Qm community, density of Ak seedlings with Sb understory was only 7% of the density of seedlings with Rs understary, suggesting the inhibitory effect of Sb. The germination rate of Ak seeds was significantly reduced by leaf extracts of Sb, and Rhododendron mucronulatum var. ciliatum(Rm) and Ak. Soil humus extract of Ak-Qm-Sb subcommunity reduced germination of Ak seeds by 81% and also reduced by 19% the respiration of mycelia of ectomycorrhizal fumgus, Lactarius sp. Among the seven phenolic compounds identified from the soil humus, extract, Ak-Qm-Sb subcommunity contained significantly high content of p-hydroxybenzoic acid, vanillic acid, and syringic acid. Particularly, p-hydroxybenzoic acid was present at 4.2ppm in the Sb roots and at 16.5ppm in the Sb humus, suggesting that it could be the primary allelopathic compound in Abies koreana forests with Sasa borealis understory.

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.1-7
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• 2004

To choose a organic acid and in-organic acid composite which is the most effective in soil-flushing process cleaning lead-contaminated sites, lead removal rates were investigated in the experiments with some organic acids; 0.01M of EDTA showed the highest lead-extraction rate ($69.4\%$) compared to the other organic acids. Furthermore, the lead removal rates were measured with 0.01M of EDIA and 0.1M of in-organic acid ; a EDTA and boric acid composite showed the highest lead-extraction rate ($68.8\%$) at pH5 compared to the other composites. As the concentration of boric acid was increased from 0.1M to 0.4M in a 0.01M of EDTA and boric acid composite, lead removal rate was decreased from $68\%\;to\;45\%$. But as the concentration of EDTA was increased from 0.01M to 0.04M in a EDTA and 0.1M of boric acid composite, permeability was decreased from $6.98{\times}10^{-4}cm/sec$ (0.01M of EDTA) to $5.99{\times}10^{-4}cm/sec$ (0.04M of EDTA). However, permeability was increased from $4.41{\times}10^{-4}cm/sec$ (0.03M of EDTA) to $6.26{\times}10^{-4}cm/sec$ (0.03M of EDTA and 0.1M of boric acid composite). indicating EDTA could increase lead dissolution/extraction rate and decrease permeability. In this system, lead remediation rate is the function of lead dissolution rate from soils and permeability of the composite into soils, and the optimized [EDTA]/[Boric acid] ratio is [0.01M]/[0.1M].

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.188-192
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• 1990

Sixteen amino acids in the hydrolysates of fulvic acid fraction from 7 plant materials were determined. Analyzed amino acids were aspartic acid, glutamie acid, arginine, histidine, lysine, glycine, alanine, valine, leucine, isoleusine, phenylalanine, tyrosine, serine, threonine, proline, and methionine. Four crop residues, wild grass cuttings and forest tree litters were put under investigation. 1. The content of amino acids in fulvic acid fractions extracted after 90 days of compositing ranged from 0.15% to 0.53% by dry weight. The highest value was found in the fulvic acids of wild grass cuttings and the lowest in those of wheat straw, being equivalent to 1/5-1/31 of those found in humic acids. 2. The group of neutral amino acids shared the largest portion followed by acidic and basic amino acids. 3. Arginine was not detected in fulvic acid fractions from well decomposed residues. 4. Aromatic amino acids, phenylalanine and tyrosine, were virtually absent in fulvic acid fractions. 5. Glycine, glutamic acid and aspartic acid were the 3 major amino acids contained in fulvic acids of well decomposed residues. With glutamic acid and aspartic acid excluded, the decreasing order of concentration of amino acids was roughly in parallel with the increasing order of molecular weight.

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.133.1-133
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• 1994

No Abstract, See Full Text

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.52-61
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• 2004

In order to remediate soils contaminated with oxyanionic As and cationic Zn and Ni through the pilot-scale acid washing, the effectiveness of acid washing and the properties of contaminated soils, fine soil particle and dissolved contaminants were evaluated. $H_{2}SO_4\;and\;H_{3}PO_4$ washing at pH $2{\sim}3$ enhanced the removal of As by the presence of competitive oxyanions and HCl washing effectively removed simultaneously As, Zn and Ni. The effectiveness of soil washing was little enhanced above the critical reaction time, and the carbonate, Fe/Mn oxide and organic/sulfides associated fraction were dominantly removed. The washing of coarse soil particles was highly efficient, but that of fine soil particles($<74{\mu}m$) was recalcitrant due to the enrichment with contaminants. Moreover, the physical separation of fine particles($<149{\mu}m$) enhanced the overall efficiency of soil washing. Therefore, both chemical extraction and separation of fine soil particles showed the high effectiveness of soil washing in the intersection point to minimize the amount of fine soil particles and to maximize the chemical extraction of contaminants.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.55-64
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• 2023

This batch experiment was conducted to investigate the patterns of major plant nutrients in the leachates from the soil that was incorporated with rice hull biochar adjusted pH with dry fish powder utilizing rice hull biochar for loading the soil microorganisms. The rice hull biochar adjusted pH between 6.0 and 7.0, and the mixture ratio of rice hull biochar and dry fish powder was 4:6. The treatments consisted of three; the soil incorporated with rice hull biochar non-adjusted pH with dry fish powder as control (RB + DF), the soil incorporated with rice hull biochar adjusted pH by pyroligneous acid solution and dry fish powder (RBP+DF), and the soil incorporated with rice hull biochar adjusted pH by citric acid solution and dry fish powder (RBC+DF). NH₄-N, NO₃-N, PO₄-P, and K concentrations in the leachates were analyzed during incubation. The accumulated NH₄-N and PO₄-P concentrations in the leachates from the RBC+DF treatment were the highest during leaching periods. The highest accumulated NO₃-N and K concentrations in the leachates from the RBP+DF treatment were observed. It observed that NH₄-N and PO₄-P were more released in the adjusted citric acid solution, but NO₃-N and K were less released than those in the pyroligneous acid solution due to their low absorption capacity. Furthermore, it is necessary to investigate crop growth responses to the soil incorporated with adjusted pH rice hull biochar and dry fish powder for loading soil microorganisms.

• Journal of Soil and Groundwater Environment
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• v.19 no.6
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• pp.6-12
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• 2014

We reviewed literature focusing on the amounts of domestic production, distribution, and consumption of strong acids and their spill cases. In particular, we investigated the chemistry and toxicity of four strong acids classified as "accident preparedness substances," including hydrochloric, nitric, sulfuric, and hydrofluoric acid. We recommend sulfuric and hydrofluoric acid as the chemicals of priority control based on the amounts used and toxicity. An advanced prevention/response system needs to be established along with an improved human and social infrastructure to prevent and efficiently respond to chemical accidents. Understanding the behavior and transport of spilled strong acids in the soil and groundwater environments requires a multi-disciplinary approach since they go through a variety of chemical and biogeochemical reactions with complex geomedia. However, no such research has been done in this area in Korea to the best of our knowledge. We expect the results of this study to contribute as basic data to future research.

• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.54-64
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• 2021

The chemical warfare agents (CWAs) have been developed for offensive or defensive purposes and used as chemical weapons in war and terrorism. The CWAs are exposed to the natural environment, transported through the water system and then eventually contaminate soil and groundwater. Therefore, effective decontamination technology to remediate CWAs are needed. The CWAs are extremely dangerous and prodution is strictly prohibited, therefore, it is difficult to use CWAs even in experimental purpose. In this study, 2,4-dichlorophenoxyacetic acid (2,4-D) was chosen as a model representative CWA because it is a simulant of anti-plant CWAs and one of the major component of agent orange. The optimum degradation conditions such as oxidant:activator ratio were determined. The effects of hydroxylamine and chelating agents such as citric acid (CA), oxalic acid (OA), malic acid (MA), and EDTA addition to increase Fe2+ activation were also investigated. Scavenger experiments using tert-butyl alcohol (TBA) and ethanol confirmed that although both sulfate (SO4•-) and hydroxyl radical (•OH) existed in Fe2+-persulfate system, sulfate radical was the predominant radical. To promote the Fe2+ activator effect, the effect of hydroxylamine as a reducing agent was investigated. In chelating agents assisted Fe2+-persulfate oxidation, the addition of 2 mM of CA and MA enhanced 2,4-D degradation. In contrast, EDTA and OA inhibited the 2,4-D removal due to steric hindrance effect.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.91.2-92
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• 2003

In order to elucidate influence of nutritional status on rice brown spot caused by Cochliobolus miyabeanus, rice cultivation soils and rice straws were collected from paddy fields where ice brown spot occurred severely, moderately, a little and none respectively. Rice plant materials were analyzed to measure inorganic nutrients in rice straws and rice seeds. Analysis of chemical properties of rice paddy soil showed that EC and contents of available phosphate, cation and silicic acid in soil with severe infections were lower than those in healthy soil. This result suggests that amount and holding capacity of nutrient contents in soils collected from paddy field with infection of C. miyabeanus are relatively low compared to those in soils collected from healthy paddy field. Analysis of inorganic nutrients in rice straws showed that amount of macronutrient elements such as silicic acids, available phosphate and total nitrogen, and micronutrients such as copper, iron and zinc in rice straws from paddy field with infection were lower than those in healthy soil. Especially amount of iron and silicic acid were very low in rice straws from paddy field soils with infection Amount of inorganic nutrients such as iron and zinc in rice seeds was the same trend as those of rice straws. These results showed that one of major factors affecting rice brown spot was amount of nutrient contents in soil and rice straw.