• Korean Journal of Soil Science and Fertilizer
• /
• v.6 no.2
• /
• pp.75-81
• /
• 1973

The morphological, physical, and chemical properties of Sonjeong series derived from acidic crystalline rocks are presented. Also it deals with the genesis and classification of the Songjeong series. Morphologically these soils have brown to dark brown loam A horizons and yellowish red to red clay loam Bt horizons with moderate, medium subangular blocky structure and thin patchy clay cutans on the ped faces. C horizons are very deep, yellowish red to yellowish brown fine sandy loam or sandy loam with original rock structure. Physically distribution of particle size indicates that clay increases with depth up to argillic horizons but below the argillic horizons clay content decrease. The moisture holding capacity is fairly good in Songjeong soils. Chemically soil reaction is strongly to very strongly acid throughout the profile and content of organic matter is less than 1 per cent except A horizons. Cation exchange capacity ranges from 5 to 9 me/100g of soils and base saturation is less than 35 per cent throughout the profile. The natural fertility of Songjeong soils are usually low. It needs lime, organic matter, and heavy application of fertilizer for the crop land. These soils occur temperate and humid climate under coniferous, deciduous, and mixed forest vegetation. Songjeong soils are classified as Red-Yellow Soils. Characteristically Songjeong soils are similar to Red-Yellow Podzolic soils in the United States but lack of A2 horizons and are quite liket Red-Yellow Soils of the Japan. According to new classification system which is 7th approximation of USDA Songjeong soils can be classified as fine loamy, mesic family of Typic Hapludults and in the FAO/UNESCO project World Soil Map as Orthic Acrisols.

• Korean Journal of Soil Science and Fertilizer
• /
• v.19 no.3
• /
• pp.187-194
• /
• 1986

Present stadies were carried out to obtain fundermental data for effective management of the soils by investigating the physicochemical characteristics rubber fiber, humification grade and bearing power of peats and muck which were included in Geongdeog series, and Gimje series in Honam area. The results abtained were as follows; 1. Humification grade of peats were about 23, while that of muck soils was about 45-71 and those were higher in Gimje series than Bongnam series. 2. The organic tiers which humification grade was higher were high pH, bulk density, and contents of K, $P_2O_5$, B.S and while were low OM, T-C, T-N, Na, $SiO_2$ and rubbed fiber. 3. In peats and mucks, bulk density, pH, contents of T-N $P_2O_5$ and ash were negatively correlated with rubbed fiber and OM, CEC, T-C, PAC, C/N, C/P were positively correlated with one, while these physicochemical characteristics were oppositely correlated with humification grade. 4. Cone bearing power of each soil tiers was low in every Geongdeog series which had the thick organic tiers and showed poorly drainage and it was the highest in Gimje series which was similar to in organic soils because of its thin organic tiers.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.4
• /
• pp.301-306
• /
• 1989

For the agricultural utilization of Korean forest land resources, which constitutes most of country, the distribution of environment and soil physico-chemical properties of establishable grass lands were clarified. The surveyed data were analized for the reasonable utilization and management of establishable grass land. The results were as follows ; 1. About 50.2% of the grass lands to be established were located under the 200m in altitude. The higher the altitude was, the more the organic matter content. 2. Tall type grass species such as Miscanthus purpurascens, Purple eulalia, and Themeda Japonica covered 71.3% of the natural vegetation in the soils of grass land to be established. 3. The extent of sandy and clayey soils which might be limited in the establishment of grassland was only 3.3%, meanwhile majority of the soils were in the favourable condition for grassland that is about 94% have more than 20cm in available soil depth and about 60.5% of the soils have less than 10% of gravels and stones in the soil profiles. 4. The chemical properties of the prearranged grassland soils were worse than the established grasslands, especially in the content of available $P_2O_5$. 5. The amount of fertilizer recommended for meadow were 286kg of nitrogen per hectare, 271kg of phosphorus, 224kg of potassium and 2040kg of calcium per hectare, but for grazing land were 201, 204, 136 and 1920kg/ha respectively.

• Korean Journal of Soil Science and Fertilizer
• /
• v.40 no.2
• /
• pp.136-144
• /
• 2007

The objectives of this study were to compare nutrient input by throughfall, stemflow and litterfall and concentration of nutrient in soil water between deciduous forest stand and Larix kaempferi plantation at Mt. Joongwang, Pyongchang-gun, Gangwon-do. The amount of rainfall interception during study period in deciduous forest stand and L. kaempferi plantation was 12% and 36%, respectively. Concentrations of cation ($Na^+$, $Mg^{2+}$, $K^+$ and $Ca^{2+}$) in throughfall were not different, while concentration of $Cl^-$ in stemflow was higher in L. kaempferi plantation. The results indicated that annual nutrient inputs by rainfall with the exception of $Cl^-$ were significantly greater in deciduous forest stand. In soil water, concentrations of anion ($Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$) in A-layer, and $Ca^{2+}$ and $Cl^-$ in B-layer were higher in L. kaempferi plantation. Litterfall input during study period was $2,589kg\;ha^{-1}$ in deciduous forest stand and $1,046kg\;ha^{-1}$ in L. kaempferi plantation. Concentration of N was higher in L. kaempferi plantation, while N input from litterfall was greater in the deciduous forest stand ($36.81kg\;ha^{-1}yr^{-1}$) than L. kaempferi plantation ($16.16kg\;ha^{-1}yr^{-1}$). $Na^+$, $Mg^{2+}$, $K^+$ and $Ca^{2+}$ in litterfall collected from deciduous forest stand were found to be higher than those from the L. kaempferi plantation. Also, input of those were greater in deciduous forest stand. Thus, total nutrient input by throughfall, stemflow and litterfall was greater in deciduous forest stand than L. kaempferi plantation, significantly.

• Tuberculosis and Respiratory Diseases
• /
• v.85 no.1
• /
• pp.37-46
• /
• 2022

Background: Although respiratory tract infection is one of the most important factors triggering acute exacerbation of chronic obstructive pulmonary disease (AE-COPD), limited data are available to suggest an epidemiologic pattern of microbiology in South Korea. Methods: A multicenter observational study was conducted between January 2015 and December 2018 across 28 hospitals in South Korea. Adult patients with moderate-to-severe acute exacerbations of COPD were eligible to participate in the present study. The participants underwent all conventional tests to identify etiology of microbial pathogenesis. The primary outcome was the percentage of different microbiological pathogens causing AE-COPD. A comparative microbiological analysis of the patients with overlapping asthma-COPD (ACO) and pure COPD was performed. Results: We included 1,186 patients with AE-COPD. Patients with pure COPD constituted 87.9% and those with ACO accounted for 12.1%. Nearly half of the patients used an inhaled corticosteroid-containing regimen and one-fifth used systemic corticosteroids. Respiratory pathogens were found in 55.3% of all such patients. Bacteria and viruses were detected in 33% and 33.2%, respectively. Bacterial and viral coinfections were found in 10.9%. The most frequently detected bacteria were Pseudomonas aeruginosa (9.8%), and the most frequently detected virus was influenza A (10.4%). Multiple bacterial infections were more likely to appear in ACO than in pure COPD (8.3% vs. 3.6%, p=0.016). Conclusion: Distinct microbiological patterns were identified in patients with moderate-to-severe AE-COPD in South Korea. These findings may improve evidence-based management of patients with AE-COPD and represent the basis for further studies investigating infectious pathogens in patients with COPD.

• Journal of Digestive Cancer Research
• /
• v.1 no.1
• /
• pp.53-57
• /
• 2013

There is no established treatment for esophageal carcinoma with metastasis. For the metastatic esophageal squamous cell carcinoma, chemotherapy or best supportive care according to patient's performance status are accepted as an available treatment. We report a case of complete remission after concurrent chemoradiotherapy for esophageal squamous cell carcinoma with metastatic lesion in 5th thoracic vertebrae. A 57-year-old man with ongoing dysphagia and weight loss was admitted to our hospital. On the endoscopic and radiologic imaging evaluation,the patient was diagnosed as a squamous cell carcinoma of esophagus with solitary metastatic lesion in 5th thoracic vertebrae. The patient was treated with combination chemotherapy (5-fluorouracil (5-FU) and cisplatin) and concurrent radiotherapy for two months to relieve dysphagia. Because metastatic lesion in thoracic vertebrae was located near the primary esophageal tumor, the metastatic lesion could be included within the radiation field. After concurrent chemoradiotherapy, consecutive 4 cycles of chemotherapy had been carried out. Primary esophageal tumor with metastatic lymph nodes and metastatic lesion in 5th thoracic vertebrae disappeared on follow up computed tomography (CT) and positron emission tomography-CT (PET-CT). Follow up endoscopic biopsy revealed no remnant malignant cells at previous primary cancer lesion.

• Korean Journal of Soil Science and Fertilizer
• /
• v.23 no.2
• /
• pp.87-93
• /
• 1990

A statistical model to predict soil temperature from the ambient meteorological factors including mean, maximum and minimum air temperatures, precipitation, wind speed and snow depth combined with Fourier time series expansion was developed with the data measured at the Suwon Meteorolical Service from 1979 to 1988. The stepwise elimination technique was used for statistical analysis. For the yearly oscillation model for soil temperature with 8 terms of Fourier expansion, the mean square error was decreased with soil depth showing 2.30 for the surface temperature, and 1.34-0.42 for 5 to 500-cm soil temperatures. The $r^2$ ranged from 0.913 to 0.988. The number of lag days of air temperature by remainder analysis was 0 day for the soil surface temperature, -1 day for 5 to 30-cm soil temperature, and -2 days for 50-cm soil temperature. The number of lag days for precipitaion, snow depth and wind speed was -1 day for the 0 to 10-cm soil temperatures, and -2 to -3 days for the 30 to 50-cm soil teperatures. For the statistical soil temperature prediction model combined with the yearly oscillation terms and meteorological factors as remainder terms considering the lag days obtained above, the mean square error was 1.64 for the soil surfac temperature, and ranged 1.34-0.42 for 5 to 500cm soil temperatures. The model test with 1978 data independent to model development resulted in good agreement with $r^2$ ranged 0.976 to 0.996. The magnitudes of coeffcicients implied that the soil depth where daily meteorological variables night affect soil temperature was 30 to 50 cm. In the models, solar radiation was not included as a independent variable ; however, in a seperated analysis on relationship between the difference(${\Delta}Tmxs$) of the maximum soil temperature and the maximum air temperature and solar radiation(Rs ; $J\;m^{-2}$) under a corn canopy showed linear relationship as $${\Delta}Tmxs=0.902+1.924{\times}10^{-3}$$ Rs for leaf area index lower than 2 $${\Delta}Tmxs=0.274+8.881{\times}10^{-4}$$ Rs for leaf area index higher than 2.

• Korean Journal of Soil Science and Fertilizer
• /
• v.18 no.3
• /
• pp.265-275
• /
• 1985

Present studies were carried out to investigate the distribution and formation of organic tiers contained paddy soils in Honam area characteristics to give basic informations on the effective utilization, management and improvement of the soils. The results obtained were summarized as follows; 1. The extent of organic tiers contained paddy soils in Honam area were 6.538㏊ and the amount of peat deposits were presumed about 2.41 million M/T. 2. Out of the total extent of the organic tiers contained paddy soils, about 97.6% was distributed in Honam plains (water-sheds of Mangyeong-Dongjin river), while about 1.5% in the Naju plains (water-sheds of Yeongsan river), and 0.9% in the Wando and Yeocheon areas. 3. The period of peat formation was presumed to be about the early of Seung Moon period (B.C. 4,250), and the Gongdeog series and the Bongnam series were formed in the bog conditions close to the valley mouth of near rolling and hill with small steram channels, and the Gimje series was formed in the out-skirts plains of the Gongdeog and Bongnam soils. 4. In the casue of peat formation, it was presumed to be the Gimje series that accumulated the fibrous peat out of the autochthonous peat such as reeds and grasses etc, to be the Gongdeog and Bongnam series that accumulated the autochtonous peat and the xylem and fibrous peat out of first allochthonous peat. 5. In the Organic horizons of these soils, the range of muck and peat horizons were in 62-68cm and 68-137cm of soil profile in the Gongdeog series, 52-84cm and 84-113cm in the Bongnam series respectively, one of muck horizon was in 46-71cm in the Gimje series. 6. The marks of soil horizons of the soils were expressed that the lower soils than the horizon of muck and peat were formed Cg, Aag for the muck horizon, 0 for the peat horizon, 0 of peat horizon were distingushed with Oag and Oig according to Organic forms. 7. The depthe occurred the muck and peat horizons were positively correlated with the width of local in the Gongdeog series ($r=0.881^{**}$, $r=0.827^{**}$), but not in the Bongnam series and Gimje series.