• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.233-239
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• 2004

This research was conducted to determine the effect of soil pH change followed by leaching with ground water on crop growth, yield and nutrient uptake of strawberry. Treatments were leaching with ground water (A), hydrated lime application of dissolved portion in $500g{\cdot}L^{-1}$ solution followed by leaching (B), application of $Al_2SO_4$ solution with the concentration of $0.75g{\cdot}L^{-1}$ followed by leaching (C), pH elevation by (B) followed by pH lowering by (C), then leaching (D). Soil samples taken before experiment had 6.0 in soil pH. But the pH of all treatments taken after pH changes and leaching were in the range from 5.8 to 6.2 without statistical differences among treatments. Electrical conductivity of soils taken before experiment was $1.82dS{\cdot}m^{-1}$ and those of (A), (B), (C), and (D) were 1.65, 1.72, 1.71 and $1.83dS{\cdot}m^{-1}$, respectively. The plant height in treatment (C) was 20.4 cm at 80 days after transplanting which was the highest among treatments tested. The other growth characteristics did not show statistical differences among treatments. Tissue contents of Fe, Mn, Zn, Cu and B in treatment (C) were higher than those of other treatments at 80 days after transplanting. The treatment (C) had the highest number of special sizes and fruit weight per 50 plants such as 137 and 3.784 g, respectively. The treatment also had 3.123 kg in total fruit weight and 2,489 kg in marketable fruit weight per 10 are. The treatment (B) also had good results such as 2,820 kg in marketable fruit weight per 10 are.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.555-559
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• 2012

Manures contain a variety of pathogenic microorganisms that pose a risk to human or animal. On-farm contaminations through contaminated manure were considered likely sources of the pathogen for several outbreak. Pathogenic microorganisms may survive in low numbers during the composting process and subsequently regrow to high levels under favorable conditions. The objective of this study was to investigate effect of temperature on survival of Salmonella enterica and Staphylococcus aureus in livestock manure compost. Commercial livestock manure compost (manure 60%, sawdust 40%) was inoculated with S. enterica and S. aureus. Compost was incubated at four different temperatures (10, 25, 35, and $55^{\circ}C$) for 20 weeks. Samples were taken every week during incubation depending on the given conditions. S. enterica persisted for up to 1 day in livestock manure compost at $55^{\circ}C$, over 140 days at $10^{\circ}C$, 140 days at $25^{\circ}C$, and 70 days at $35^{\circ}C$, respectively. S. aureus persisted for up to 1 day in livestock manure compost at $55^{\circ}C$ and 90 days at $10^{\circ}C$, 70 days at $25^{\circ}C$, and 40 days at $35^{\circ}C$, respectively. The results indicate that S. enterica and S. aureus persisted longer under low temperature condition. S. enterica survived longer than S. aureus at three different temperatures (10, 25, and $35^{\circ}C$). This study will provide useful and practical guidelines to applicators of soil in deciding appropriate handling and time frames for land application of livestock manure compost for sustainable agriculture. Results from these studies provide useful information in identifying manure handling practices to reduce the risk of S. enterica and S. aureus transmission to fresh produce.

• Applied Biological Chemistry
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• v.18 no.3
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• pp.123-144
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• 1975

This study has been carried out to investigate the translocation-illuviation status of iron and manganese, which are striking phenomena in paddy soils, in relation to its morphological characteristics, and to find out a method to identify illuvial layer of iron quantitatively. Determination of active iron and easily reducible manganese content in surface soils of lowland paddy (266 samples) in Korea were conducted. The examination has been made on relationship between morphological, physico-chemical properties of the representative paddy soils (9 series) and iron and manganese content of their horizons. The results are summarized as follows. 1. The poorer the drainage, the higher concentration of active iron and easily reducible manganese were found, and under same drainage condition, the more the sand, the lower the content of them. 2. Irrespective of soil texture and drainage, highly signignificant positive correlation was found between the contents of active iron ($\hat{Y}$) and clay plus silt in surface soils. $$\hat{Y}=0.3929+(0.05352\;X\;clay%)+(0.0001023\;X\;silt%){\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;I$$ No correlation, however, was found between clay content and easily reducible manganese concentration. 3. Significant positive correlation was obtained between active iron ($\hat{Y}$) and total iron (x) content in each profiles of all soil series. Obtained regression equation is as follows; $$\hat{Y}=0.361x-0.480(r=0.651^{**}){\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;II$$ On the other hand, easily reducible manganese concentration had a tendency to increase, not significantly, with increasing total manganese concentration. 4. Accumulation of iron and manganese generally can be found in paddy soils, but distinct accumulation was found under moderately well drained fine loamy and clay soils, while surface accumulation occurred under poor drainage without regard to soil texture. 5. Profile description or determination of active iron in each horizon were found to be insufficient to designate illuvial layer of iron. Therefore, identification of illuvial layer of iron based on the ratio of total iron and active iron, and concentration of active iron estimated by the content of clay plus silt (Equation 1 above) was thought to be reasonable. Also, manganese accumulation layer would be estimated by total manganese and easily reducible manganese content and their ratio.

• Korean Journal of Plant Taxonomy
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• v.41 no.1
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• pp.66-80
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• 2011

This study investigated the environmental factors and conducted a RAPD analysis for a better understanding of the environmental characteristics and regional genetic variation in samples from 18 different areas of Viola diamantiaca. The habitats are mostly located on the slopes of mountains facing north at an altitude ranging from 614 m to 1,462 m above sea level with angles of inclination ranging from 3 degrees to 30 degrees. A total of 268 vascular plant taxa are identified in 35 quadrates of 18 habitats. The importance value of V. diamantiaca is 11.58%, and four highly ranked species, Sasa borealis (5.61%), Meehania urticifolia (5.21%), Ainsliaea acerifolia (3.62%), Pseudostellaria palibiniana (3.60%) are considered to have an affinity with V. diamantiaca in their habitats. The degree of their average species diversity is 1.36, while this metric for their evenness and dominance are 0.89 and 0.07, respectively. The average field capacity of the soil is 25.99%, with organic matter at 17.47%, and the pH is 5.19. The soil texture was confirmed as sandy loam of eleven and loam of seven. The result of the RAPD analysis, among 78 bands amplified with a primer, 64 (84.6%) showed polymorphism. Eighteen populations could be classified into five groups with similarity coefficient values ranging from 0.53 to 0.86. The Mt. Jiri population, which is geographically segregated, shows basal branching within the 18 populations. Five populations, including two in the southern district in Gangwon-do and three in Chungcheongbuk-do, form a distinct clade. Four populations in the central district of Gangwon-do and Mt. Bohyeon in the Gyeongsangbuk-do clade form a sister to the clade containing two populations in Gyeonggi-do and five populations of the northern district in Gangwon-do. The Mt. Gariwang population is placed between the southern district and the central district in the Gangwon-do clades.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.453-466
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• 2006

To comply with stricter regulations provoked by increasing odor nuisance, it is imperative to practice effective odor control for sustainable livestock production. This study was conducted to assess odor and odorous compounds emitted from liquid animal manure with different treatment methods such as Fresh Manure(without treatment, FM), Anaerobic Digestion(AD) and Thermophilic Aerobic Digestion(TAD) and their application to soil. Air samples were collected at the headspace of liquid manure, upland and paddy soil, and analyzed for odor intensity and offensiveness using an olfactometry; odor concentration index using odor analyser; nitrogen-containing compound such as ammonia(NH3) using fluorescence method; and sulfur containing compounds such as hydrogen sulfide(H2S), methyl mercaptan(MeSH), dimethyl sulfide(DMS) and dimethyl disulfide(DMDS) using gas chromatography-pulsed flame photometric detector, respectively. Odor intensity, offensiveness and concentration index from TAD liquid manure was statistically lower than those from FM and AD(p<0.01). Mean concentrations of H2S, MeSH, DMS, DMDS and NH3 were 65.93ppb, 18.55ppb, 5.26ppb, 0.33ppb and 10.57ppm for liquid manure with AD; and 5.15ppb, 0.97ppb, 0.80ppb, 0.56ppb and 1.34ppm for liquid manure with TAD, respectively. More than 60% of malodorous compounds related to nitrogen and sulfur were removed by heterotrophic microorganisms during TAD treatment. When liquid manure was applied onto upland and paddy soil, NH3 removal efficiencies ranged from 51 to 94% and 22 to 91% for AD and TAD liquid manure, respectively. The above results show that liquid manure with TAD is superior to AD and FM with respect to the odor reduction and odor problem caused by land applied liquid manure is directly related to the degree of odor generated by the manure treatment method.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.828-832
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• 2013

To report country-specific carbon and nitrogen stocks data in a pear orchard by Tier 3 approach of 2006 IPCC guidelines for national greenhouse gas inventories, an experimental pear orchard field of the Pear Research Station, National Institute of Horticultural & Herbal Science, Rural Development Administration, Naju, Korea ($35^{\circ}01^{\prime}27.70N$, $126^{\circ}44^{\prime}53.50^{\prime\prime}E$, 6 m altitude), where 15-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees were planted at a $5.0m{\times}3.0m$ spacing on a Tatura trellis system, was chosen to assess the total amount of carbon and nitrogen stocks stored in the trees and orchard soil profiles. At the sampling time (August 2012), three trees were uprooted, and separated into six fractions: trunk, main branches, lateral branches (including shoots), leaves, fruits, and roots. Soil samples were collected from 0 to 0.6 m depth at 0.1 m intervals at 0.5 m from the trunk. Dry mass per tree was 4.7 kg for trunk, 13.3 kg for main branches, 13.9 kg for lateral branches, 3.7 kg for leaves, 6.7 kg for fruits, and 14.1 kg for roots. Amounts of C and N per tree were respectively 2.3 and 0.02 kg for trunk, 6.4 and 0.07 kg for main branches, 6.4 and 0.09 kg for lateral branches, 6.5 and 0.07 kg for roots, 1.7 and 0.07 kg for leaves, and 3.2 and 0.03 kg for fruits. Carbon and nitrogen stocks stored between the soil surface and a depth of 60 cm were 138.29 and $13.31Mg{\cdot}ha^{-1}$, respectively, while those contained in pear trees were 17.66 and $0.23Mg{\cdot}ha^{-1}$ based on a tree density of 667 $trees{\cdot}ha^{-1}$. Overall, carbon and nitrogen stocks per hectare stored in a pear orchard were 155.95 and 13.54 Mg, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.329-336
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• 1989

A series of green house experiment was conducted to find but the effect of fertilizer application and inoculation of rhizobium on the changes of amide-N, ureide-N and $NH_4-N$ concentration in stem and root exudates of soybean plant growth. The results obtained were summarized as follows ; 1. Five strains of indigenous Rhizobium japonicum-nitrogen fixing activity($C_2H_2$-reducing activity) was more than 6.4 to 20.1 nmole/hr/tube-were identified from 37 soil samples in 22 areas of farmers field throughout country. 2. These identified 5 strains of rhizobium were obtained high nitrate reductase but low ammonium and nitrite oxidase activities. Among 5 strains of rhizobium the Rhizobium japonicum RjK-134 was applied for this green house experiment. 3. Dry matter yield was increased by the combination of inoculation of Rhizobium japonicum RjK-134 with no fertilizer and without nitrogen fertilizer application. However, dry matter yield was decreased with application of N and NPK with inoculation of rhizobium. 4. The concentrations of amide-N and ureide-N were increased in xylem sap than that of root exudate and higher concentration was obtained ar 30 days after planting than flowering stage (45 days after planting). 5. The combination of NPK application with inoculation of Rhrizobium japonicum RjK-134 enhanced the increase of amide-N and ureide-N concentration in xylem sap and root exudate. 6. High ammonium-N concentration in xylem sap and root exudate were obtained in combination with without-fertilizer under no inoculation of rhizobium and N and NPK application with inoculation of rhizobium.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.4
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• pp.233-252
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• 2021

This paper is a study to improve the efficiency of mixing technology in the shield TBM chamber. Currently, the number of construction cases using the TBM method is increasing in Korea. According to the increasing use of TBM method, research on TBM method such as Disc Cutter, Cutter bit, and Segment also shows an increasing trend. However, there is little research on the mixing efficiency in chamber and chamber. In order to improve the smooth soil treatment and the behavior of the excavated soil, a study was conducted on the change of the mixing efficiency according to the effective mixing bar arrangement in the chamber. In the scale model experiment, the ground was composed using plastic materials of different colors for ease of identification. In addition, the mixing bar arrangement was different and classified into 4 cases, and the particle size distribution was classified into single particle size and multiple particle size, and the experiment was conducted with a total of 8 cases. The rotation speed of the cutter head of all cases was the same as 5 RPM, and the experiment time was also carried out in the same condition, 1 minute and 30 seconds. In order to check the mixing efficiency, samples at the upper, middle (left or right), and lower positions of each case were collected and analyzed. As a result of the scaled-down model experiment, the mixing efficiency of Case 4 and Case 4-1 increased compared to Case 1 and Case 1-1, which are actually used. Accordingly, it is expected that the mixing efficiency can be increased by changing the arrangement of the mixing bar in the chamber, and it is considered to be effective in saving air as the mixing efficiency increases. Therefore, this study is considered to be an important indicator for the use of shield TBM in Korea.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.274-283
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• 2023

Buffer zones, an example of nature-based solutions, offer wide range of environmental, social and economic benefits due to their multifunctionality when applied to watershed areas promoting blue-green connectivity. This study evaluated the effects of buffer zone application to the water quality of Yongdam reservoir tributaries. Particularly, the challenges and improvement of the buffer zone design were identified and suggested, respectively. Water and soil samples were collected from a total of six sites in Yongdam reservoir from September 2021 to April 2022. Water quality analyses revealed that among the sites monitored, downstream of Sangjeonmyeon Galhyeonri (SG_W_D2) was found to have the highest concentration for water quality parameters turbidity, total suspended solids (TSS), chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN). This finding was attributed to the algal bloom observed during the sampling conducted in September and October 2021. It was found through the soil analyses that high TN and TP concentrations were also observed in all the agricultural land uses implying that nutrient accumulation in agricultural areas are high. Highest TN concentration was found in the agricultural area of Jeongcheonmyeon Wolpyeongri (JW_S_A) followed by Jucheonmyeon Sinyangri (JS_S_A) while the lowest TN concentration was found in the original soil of Sangjeonmyeon Galhyeonri (SG_S_O). Among the types of buffer zones identified in this study, Type II-A, Type II-B and Type III were found to have blue-green connectivity. However, initially, blue-green connectivity in these buffer zone types were not considered leading to poor design and poor performance. As such, improvement in the design considering blue-green network and renovation must be considered to optimize the performance of these buffer zones. The findings in this study is useful for designing buffer zones in the future.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.108-114
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• 2014

To analyze the hazards associated with cucumber and hot pepper cultivation areas, a total of 72 samples were obtained and tested to detect the presence of biological (sanitary indicative, pathogenic bacteria and fungi) and chemical hazards (heavy metals and pesticide residues). The levels of sanitary indicative bacteria (aerobic plate counts and coliforms) and fungi were ND-7.2 and ND-4.8 log CFU/(g, mL, hand, or $100cm^2$) in cucumber cultivation areas, and ND-6.8 and 0.4-5.3 log CFU/(g, mL, hand, or $100cm^2$) in hot pepper cultivation areas. More specifically, the soil of hot pepper cultivation areas was contaminated with coliforms at a maximum level of 5.6 log CFU/g. Staphylococcus aureus was detected only in glove samples at a level of 1.4 log CFU/$100cm^2$ and Bacillus cereus was detected in the majority of samples at a level of ND-4.8 log CFU/(g, mL, hand, or $100cm^2$). Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella spp. were not detected. Heavy metal (Zn, Cu, Ni, Pb, and Hg) chemical hazards were detected at levels lower than the regulation limit. Residual insecticides were not detected in cucumbers; however, hexaconazole was detected at a level of 0.016 mg/kg (maximum residue limit: 0.3 mg/kg) in hot peppers.