• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.5
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• pp.25-30
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• 2017

Hydrologic soil group is one of the important factors to determine runoff potential and curve number. This study was conducted to classify the hydrologic soil groups of Korean soils by considering saturated hydraulic conductivity and depth of impermeable layer. Saturated hydraulic conductivity of Korean soils was estimated by pedotransfer functions developed in the previous studies. Most of paddy soils were classified as D type due to shallow impermeable layer and low saturated hydraulic conductivity in B soil horizon. For upland and forest, soils classified to A and D types increased compared with former classification method because underestimated permeabilities and overestimated drainages were corrected and rock horizon in shallow depth was regarded as impermeable layer. Soils in mountainous land showed the highest distribution in A type, followed by D type. More than 60 % of soils in mountain foot-slope, fan and valley, alluvial plains, and fluvio-marine deposits were classified to D type because of land use such as paddy and upland.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.333-339
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• 2000

Effects of chemical properties of cultivation soils on the growth and quality of garlics were investigated. Garlics were cultivated in Uisung and Yechun, one of the major areas of garlic production, where upland and paddy fields have been used for garlic production for many years. Contents of phosphate, sulfur and potassium in the soils of paddy fields were relatively higher than those in the soils of upland fields, suggesting that the accumulation of inorganic salts has been progressed in the paddy fields. Soils of Uisung area showed higher pH s and lower contents of available phosphate compared to those of Yechon area. This result implies that the soils of Uisung area provide somewhat better chemical properties for garlic growth than those of Yechun area. Contents of inorganic salts such as phosphate, potassium and magnesium in the soils significantly affected the growth and quality of garlics. Garlics grown in the soils with lower contents of these inorganic salts exhibited better growth status and contained more pyruvate. More pyruvate was found in the garlics grown in upland fields than in paddy fields. Therefore, it is apparent that the accumulation of inorganic salts, especially available phosphate, in cultivation soils leads to the inhibition of garlic growth and in turn to the deterioration of garlic quality.

• The Korean Journal of Mycology
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• v.29 no.2
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• pp.123-126
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• 2001

A survey of 43 soil samples collected from southern Korea has shown that nematophagous fungi occurred in a variety of habitats. Nine predatory and two endoparasitic species were isolated. Habitats were classified into four types, i. e., mountain, upland, paddy field and greenhouse. Of these, greenhouse and upland had the highest incidence of nematophagous fungi $(95{\sim}100%)$ compared with mountain (37.5%) and paddy field (16.7%). The most common species was Arthrobotrys oligospora Fres., which was isolated from 25.5% of soil samples. Net forming species were the most abundant (72.5%), followed by constricting ring (10.0%), adhesive hyphae (7.8%), endoparasitic fungi (5.0%), and adhesive knob (4.8%). Nematophagous fungi were isolated move frequently from cultivated soil rather than uncultivated mountainous soil.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.179-183
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• 1987

A series of laboratory experiments were conducted to find out the populations and identification of soil bacteria, fungi and their B/F ratio in the rhizosphere of intensively cultivatad hot-pepper, garlic, flower plants, chinese cabbage, and round onion. The results obtained are summarized as follows: 1. The number of bacteria, fungi and their B/F ratio are remarkably lower than that of normal paddy soils. 2. Nitrate reducers and bacteria which utilized simple sugars for their sole carbon source are predominated in the rhizosphere of intensively cultivated upland crops. 3. Alkaligenetic bacteria predominate in rhizosphere of garlic and tomato cultivated upland soils. 4. Genera of Pseudomonas, Xanthomonas, Bacillus, Arthrobacter, and Achromobacterium are the most common species in the rhizosphere of intensively cultivated upland crops and flower plants. 5. Phytotoxin producers such as Stachybotris sp. were identified in all rhizospheres of intensively cultivated upland crops and flower plants. 6. Most common and highest population of soil fungi were obtained for the genera of Penicillium, Humicola, Phoma and Aspergillus in the rhizosphere of intensively cultivated upland crops and flower plants.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.182-189
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• 1986

Alachlor, 2-chloro-2',6'-diethyl-N-(methoxymethyl) acetanilide produced four major degradation products, when incubated under an upland soil condition for 80 days. They include 8-ethyl-2-hydroxy-N-(methoxymethyl)-1,2,3,4-tetrahydroquinoline (m/z 221), N-hydroxyacetyl-2,3-dihydro-7-ethylindole (m/z 205), 2-hydroxy-2',6'-diethyl-N-(methoxymethyl) acetanilide (m/z 251), and 9-ethyl-1,5-dihydrol-(methoxymethyl)-5-methyl-4,1-benzoxazepin-2 (3H)-one (m/z 249). The products turned out to be a little different from those obtained under the flooded paddy soil condition used in the previous paper. The plausible pathways for the degradation were proposed.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.1
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• pp.24-28
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• 1997

The field experiment for field desalinization by precultivation of orchard crops were carried out to evaluate relationship between the varieation of chlorine contents of soil and crop uptake in the upland diverted from paddy field. After harvest of grass crops, soil samples were taken for analysis of chlorine contents of soil layers. Regardless of kinds of grass crops cutivated, contents of soil chlorine were decreased comparing to non-crop plot. Chlorine content in plant harvested at just before the flowering stage was much higher than that of after flowering. Chlorine uptake and dry matter were increased in order of Italian ryegrass, Perennial ryegrass, and Sudan grass. Positive correlations were showed between chlorine uptake and dry matter. The content of soil chlorine decreased by higher yield of dry matter.

• Korean Journal of Soil Science and Fertilizer
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• v.51 no.1
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• pp.50-60
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• 2018

This study was to evaluate the effect of organic amendments incorporation on soil properties and plant growth under two different soil salinity levels and various cultivated crops at Saemangeum reclaimed tidal land for three years from 2012 to 2014. The soil texture of the experimental site was sandy loam. Four different crops, sesbania (Sesbania grandiflora), sorghum-sudangrass hybrid (Sorghum bicolor-Sorghum sudanense), rice (Oryza sativa L.) and barley (Hordeum vulgare) were cultivated at low (< $1dS\;m^{-1}$) and high (> $4dS\;m^{-1}$) soil salinity levels. The soil salinity was significantly lowered at the rice cultivation site compared to continuous upland crops cultivation site in high soil salinity level. But the soil salinity was increased as cultivating sesbania coutinuously in low soil salinity level. The soil organic matter content was increased with the incorporation of straw at the continuous site of rice and barley, and the average of soil organic matter was increased by $0.9g\;kg^{-1}$ per year which was effective in soil aggregate formation. The highest biomass yield plot was found in barley (high salinity level) and sesbania (low salinity level) cultivation site, respectively. Our research indicates that rice cultivation in paddy field with high salinity level was effective in lowering soil salinity and sesbania cultivation was useful to biomass production at upland with low salinity. In conclusion, soil salinity and organic matter content should be considered for multiple land use in newly reclaimed tidal land.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.204-207
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• 2008

The purpose of this study is to identify how much the MODIS NDVI (Normalized Difference Vegetation Index) can explain the soil moisture simulated from SWAT (Soil and Water Assessment Tool) continuous hydrological model. For the application, ChungjuDam watershed (6,661.3 $km^2$) was adopted which covers land uses of 82.2 % forest, 10.3 % paddy field, and 1.8 % upland crop respectively. For the preparation of spatial soil moisture distribution, the SWAT model was calibrated and verified at two locations (watershed outlet and Yeongwol water level gauging station) of the watershed using daily streamflow data of 7 years (2000-2006). The average Nash and Sutcliffe model efficiencies for the verification at two locations were 0.83 and 0.91 respectively. The 16 days spatial correlation between MODIS NDVI and SWAT soil moisture were evaluated especially during the NDVI increasing periods for forest areas.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.2
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• pp.81-85
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• 1996

Tentative consolidation criteria, a kind of land suitability classification, was established for cultivated upland soils. The criteria were composed of systematically quantified individual soil properties such as physiography(relief), slope, available soil depth etc., and local features such as soil complexity, mapping unit separation, width/length ratio etc. The criteria was applied to upland soils in granite area, and sedimentary rock area. It was clear that the comparison of local features among candidated areas, and classification of suitability classes for land consolidation of upland soils was satisfactory for selection. The status of the areas classified to "Well suitable" were distributed on alluvial plains or less dissected rollings with lower complexity of soils occurred and extended acreage in each mapping unit. On the other hand, the areas classified as "Unsuitable" were distributed on the elongated narrow valleys with quite divided mapping units by paddy fields on the valley bottom.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.239-247
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• 2022

The physico-chemical properties of agricultural soil are factors that affect crop productivity and soil fertility. In Korea, agricultural environment change surveys have been conducted every four years since 1999. The purpose of this study is to investigate the status and changes in the physico-chemical properties of agricultural soil in Chungcheongnam-do. Samples were collected from the exact location of the aforementioned environment survey, and environmental variables (land use, type of crop cultivated) were investigated in relation to the samples. Soil collection was conducted using a core sampler and a single gouge auger. The bulk density of the soil generally increased up to a depth of sampling of 40 cm but decreased thereafter to a depth of 60 cm. Additionally, the bulk density was highest in the upland soil case and stood at 1.59 g·cm^-3, while the lowest value of 1.52 g·cm^-3 was obtained from orchard soil samples. Conversely, the porosity and moisture gradually decreased at soil depths of 0 - 40 cm and increased at depths of 40 - 60 cm. Most of the soil chemical properties generally decreased with an increase the soil depth from 0 to 70 cm, but electrical conductivity (EC) increased up to a depth of 40 cm. Therefore, it is judged that it is necessary to lower the bulk density by supplying organic matter for agricultural land in Chungcheongnam-do.