• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.251-259
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• 2000

Monthly variations of physico-chemical and biological parameter were determined in near the Kum River mouth at lower discharge period from January 1998 to September 1999. The characteristics of water quality was showed hypertrophic with average values of total nitrogen (TN), total phosphorus (TP), chlorophyll-a and transparency are 3.9 mg N/l, $160\;{\mu}g/l$, $73\;{\mu}g/l$ and 0.8 m, respectively. Among a nitrogen component, inorganic and organic nitrogen comprised 34% and 66% of TN, $NH_4$ and $NO_3$ comprised 30% and 70% of inorganic nitrogen respectively. SRP concentration comprised below 9% of TP. TN/TP and DIN/SRP ratio in winter were higher than in summer. SRSi fluctuation was very wide as ranged from 0 to 3.0 mg Si/l and the highest after flood event in summer. Long-term depleted pattern of Si was observed, that is considered to be important nutrient for algal growth. Chlorophyll-a concentration was very high as $113\;{\mu}g/l$, $162\;{\mu}g/l$ in winter and summer respectively, which persisent bloomed diatom Stephanodiscus and blue-green algae Microcystis. In consequence, water quality management of these periods are considered very important.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.98-111
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• 2015

Urban environmental problems such as flooding, depletion of ground water, pollution of urban streams and the heat island effect caused by urban development and climate change can be mitigated by the improvement of the urban water cycle. For the effective planning of water cycle management it is necessary to establish aerial Hydrotope Maps, with which we can estimate the status and change of the water allowance for any site. The structure of the German water balance model BAGLUVA, which is based on soil and vegetation, was analyzed and the input data and boundary condition of the model was compared with Korean data and research results. The BAGLUVA Model consists of 5 Input categories (climate, land use, topography, soil hydrology and irrigation). The structure and interconnection of these categories are analyzed and new concepts and implementation methods of topographic factor, maximum evapotranspiration ratio, effective rooting depth and Bagrov n parameter was compared and analyzed. The relation of real evapotranspiration ($ET_a$)-maximum evapotranspiration ($ET_{max}$) - precipitation (P) was via Bagrov n factor represented. The aerial and land use oriented Hydrotope Map can help us to investigate the water balance of small catchment areas and to set goals for volume of rainwater management and LID facilities effectively in the city. Further, this map is a useful tool for implementing water resource management within landscape and urban planning.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.17-25
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• 2001

High salt content in food waste limit use as the potential source of compost. Since sodium chloride content should be lower than one percent to meet requirement for agricultural use of compost, we attempted use of three kinds of co-composting material for food wastes compost, which were fermented, dried, and fresh types of amendments which included pig manure, sawdust and puffed rice hull. Food wastes were composted well and stabilized after around the 40th days of composting. Little difference were found between composts amended sawdust and puffed rice hull. The result indicated that puffed rice hull could be used as a good alternative of sawdust. Because sawdust or puffed rice hull were mixed as amendments to control water contents and to dilute high NaCl content of compost material, the C/N ratios of the final products were significantly high over 40. However, NaCl contents of final products were dropped to less than percent on the fresh weight basis by mixing food wastes and the above amendments with the optimum rates.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.50-56
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• 1994

This study was investigated for the purposes of securing forage resource using idled rice paddy recently increased in accordance to a current trend of farm products' liberalization and also of presevation of environment by using cattle sluny as liquid manure, which is seriously increasing these days. In this study, mean annual dry matter yield and its seasonal variation with reed canarygrass, and a optimum rate of cattle sluny application were investigated. The results are as follows: 1. According to the conditions of cutting frequencies(3, 4 and 5 cutting per year), mean annual dry matter yield was recorded from 8.9 tons to 10.9 tons per hectare and was the highest at 3 cutting frequency. 2. The use of cattle sluny with the levels of between 300 and 360 kg N per hectare showed a significantly higher mean annual dry matter yield than that of the control (non-fertilization). 3. The treatments with 3 and 4 cutting frequencies(90 kg Nhdyear, 120 kg Nhdyear) recorded higher dry matter yields than the control of the former level by 1.23 tons and 2.34 tons respectively and in the treatment of 5 cutting frequency, the second level with cattle sluny of 300 kg Nhdyear showed an increased dry matter yield of 2.11 tons compared to the former level(l50 kg Nhdyear). With regards to nitrogen efficiency, one kg of nitrogen is applied to 13.7, 19.4 and 14.1 kg of dry matter yields in the conditions of 3, 4 and 5 cutting frequencies respectively. 4. In view of seasonal variance of annual dry matter yield, the second cut in 3 cutting frequency, the third cut in 4 cutting frequency and the third in 5 cutting frequency showed the highest ratio as 42, 37 and 32% respectively compared to the total. 5. Under the conditions of this study, the 'Input-Output curve' from 5 cutting frequency was the closest to sigmaformed process(i=0.9993) of various cutting frequencies, and the maximum marginal yield in the treatment was obtained at the level of 250 kg Nha with cattle sluny. The economic level of cattle sluny was between 371.0 and 402.2 kg N and the highest dry matter yield was obtained at 489.3 kg Mdyear in the same treatment

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.244-251
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• 1991

This study was undertaken to assess the effectiveness of magnesium-and boron-enriched complex fertilizer(CF, N-P$_2$O$_{5}$-K$_2$O-MgO-B$_2$O$_3$: 14-10-12-3-0.2) on the maintenance and management of hilly pasture. The effectiveness of CF was compared to those of some straight fertilizers (SF). This first part of the study was concerned with the soil chemical properties and the mutural balances of mineral nutrients in the soils of a mixed grass-clover and a pure grass swards. The results of a two-year field experiment are summarized as follows: 1. The Mg contents in the soils of the CF plots were higher than those of the SF plots. On the other hand, the Ca contents were higher in the SF plots than in the CF plots. The contents of Mg and Ca, and CEC, except K, in both the CF and SF plots were considerably below the optimum levels. At the normal application rate of NPK, the contents of available P$_2$O$_{5}$ were close to the optimum level in both the CF and SF plots. 2. The contents of exchangeable Mg were lower than the K contents in soils of all the plots. At the normal application rate of NPK, the Mg contents in the CF plots, but not in the SF plots, were close to the critical level for general crops (0.29me Mg/100g soil). The Mg contents in soils of all the plots, however, were considerably below the critical level for pasture forages and grazing cows (0.41me/100g). 3. Considering the desirable base saturation level of soil, the saturation levels of Ca and Mg were insufficient in both the CF and SF plots. The saturation levels of Mg in the CF plots, however, were relatively good compared with the SF plots. The equivalent ratios or Mg/K, Ca/Mg. Ca:Mg:K, and %Mg of CEC in soils were generally unfavorable in all the plots. These ratios of the CF plots, however, were relatively better than those of the SF plots. 4. Considering the contents of exchangeable Ca and Mg in soils, it is suggested that the application of slaked magnesium lime as a soil amelioration might be desirable for the fundamental increment of those contents at pasture establishment.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.239-253
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• 1999

The objective of this study was to determine the effects of various kinds of composts on the change of soil chemical properties in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The continuous application of human excrement sludge decreased soil pH up to 4.4~5.0, while other compost treatments increased soil pH compared with control plot. The EC increased initially and showed their maximum values at 20days after compost application, and then decreased up to 40 days, thereafter kept a certain level. The available phosphorous accumulated at 0~20cm depth in loam soil, and 0~50cm in sandy loam soil. Annual accumulation rates were 17% higher in sandy loam soil than loam soil. The more compost application rates and times, the higher base saturation percentage increased in upland soils. Four year's application at a rate of $80Mg\;ha^{-1}$ per year increased the base saturation percentage to 87~91% compared with 45% at control plot in the loam soil. While in sandy loam soil only three year's application of same rate increased the base saturation percentage to 81~92% compared with 30.4% at control plot. The average annual increasing rate of base saturation percentage at the same application rates of composts were higher in sandy loam soil by 2.0~3.7 times than in loam soil. The application of compost increased the exchangeable Ca, Mg, and K contents of soils by 2, 2~3, and 3~5 times, respectively, compared with the control. The contents of exchangeable canons were high in surface soil. and decreased with increase of soil depths. In the case of heavy metal content, there were no difference at the application of PMC and CMC but Ni. Fe, Zn, Cu was increased a little when the HES applied, and Ni and Cr was increased application with FISC.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.418-423
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• 2017

In hydroponics, the nutrient solution is supplied considering the water and nutrient uptake characteristics of crops. However, as the ionic uptake characteristics are changed as a result of the weather conditions or the growth response of the crops, the root zone can not be maintained in optimal condition. In addition, the coir substrate has been used mainly for the tomato cultivation in place of the inorganic substrate, there are few studies on long-term cultivation using coir substrate. Therefore, this study was conducted to investigate the effect of EC level of irrigation solution on tomato growth and inorganic ions of root zone in soilless culture using coir. Coir substrate mixed with 5 : 5 chip and dust was used. EC level of irrigation solution was 1.0, 1.5, 2.0, and $3.0dS{\cdot}m^{-1}$. At the initial stage, $NO_3-N$, P, Ca and Mg in the drainage were lower than the irrigation level at 1.0 and $1.5dS{\cdot}m^{-1}$. However, EC $2.0dS{\cdot}m^{-1}$ or higher, all the ions except P were highly concentrated in the drainage. The average fruit weight was not significantly different between 1.0 and $1.5dS{\cdot}m^{-1}$ until 3th cluster, but from the next cluster, the higher the EC level, the smaller the weight. The number of fruit and yield to 6th cluster was the highest at $1.5dS{\cdot}m^{-1}$. From the next cluster, The yield was decreased with the higher EC level. At the early stage of growth, BER occurred only in EC $3.0dS{\cdot}m^{-1}$, but increased in all treatments with increasing irradiation. The incidence rate of EC $3.0dS{\cdot}m^{-1}$ was higher than that of the lower EC level treatment.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.486-491
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• 2007

Background: This study examined the relationship between the pleural adenosine deaminase (ADA) level and the patterns of pleural enhancement in patients with a tuberculous pleural effusion (TPE) shown on a CT scan. Methods: The charts and CT findings of 44 patients with TPE from February 2002 to October 2006 were reviesed retrospectively. A diagnosis of TPE was made by the pleural ADA level with a follow-up (24/44), sputum smear or culture of sputum (16/44), pleural fluid culture (3/44) or pleural biopsy (1/44). The patients were divided into two groups according to the ADA level(Group I [n=12]: 40-70, Group II [n=32]: >70 U/L). The presence or absence, maximal thickness and patterns of pleural enhancement were analyzed. The pattern of pleural enhancement was classified into diffuse or focal, smooth or irregular and interrupted or continuous. The difference in CT findings between groups I and group II were analyzed using an unpaired T test, Chi-square test and Z test. Results: All 44 patients showed diffuse pleural enhancement on the CT scans. The maximal pleural thickness of groups I and II was $1.83{\pm}1.03mm$ (1-4 mm) and $3.63{\pm}1.78mm$ (1-8 mm), respectively (p =0.0002). Pleural thickening ${\geq}5mm$ was only demonstrated in 31.3% of patients in group II (10/32). Diffuse interrupted pleural thickening was noted in 91.7% (11/12) of patients in group I and 62.5% (20/32) in group II, respectively. Diffuse continuous pleural thickening was observed in 8.3% (1/12) of patients in group I and 37.5% (12/32) in group II, respectively (p=0.0748). Conclusion: Pleural thickening ${\geq}5mm$ on the contrast enhanced CT is rare in patients with lymphocyte-dominant TPE in whom the pleural ADA level is between 40-70 U/L.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.416-431
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• 2000

The objective of this study was to determine the effects of various kinds of composts on the change of soil chemical properties in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The continuous application of human excrement sludge decreased soil pH up to 4.4~5.0, while other compost treatments increased soil pH compared with control plot. The EC increased initially and showed their maximum values at 20days after compost application, and then decreased up to 40 days, thereafter kept a certain level. The available phosphorous accumulated at 0~20cm depth in loam soil, and 0~50cm in sandy loam soil. Annual accumulation rates were 17% higher in sandy loam soil than loam soil. The more compost application rates and times, the higher base saturation percentage increased in upland soils. Four year's application at a rate of $80Mg\;ha^{-1}$ per year increased the base saturation percentage to 87~97% compared with 45% at control plot in the loam soil. While in sandy loam soil only three year's application of same rate increased the base saturation percentage to 81~92% compared with 30.4% at control plot. The average annual increasing rate of base saturation percentage at the same application rates of composts were higher in sandy loam soil by 2.0~3.7 times than in loam soil. The application of compost increased the exchangeable Ca, Mg, and K contents of soils by 2, 2~3, and 3~5 times, respectively, compared with the control. The contents of exchangeable cations were high in surface soil, and decreased with increase of soil depths. In the case of heavy metal content, there were no difference at the application of PMC and CMC but Ni, Fe, Zn, Cu was increased a little when the HES applied, and Ni and Cr was increased application with FISC.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.1
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• pp.1-6
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• 2001

This experiment was conducted to evaluated the effect of maturity at harvest on the changes in quality of round baled rye silage at forage experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon in 1998. The experimental design was a split-plot design with three replications. The main plots were three different harvest stages : boot, heading and flowering stages, and the subplots were days after ensiling : 1, 2, 3, 5, 10, 30, 45, and 60 days. The wilting period of boot, heading and flowering stages were 1, 0.5 and 0.5 days, respectively. The final pH of rye silage was higher in the order of flowering, boot and heading stages. And pH of flowering stage began to change at early fermentation period, but that of boot and heading stages was delayed 1~2 days. Ammonia-N content of boot stage was highest. and that was increased as fermentation progressed. But Ammonia-N of heading stage was decreased to 30 days. then that was increased after 45 days fermentation. Among fermentation periods, inside temperature of deep place was not affected by external temperature. And that of deep place was increased to 3$0^{\circ}C$ at early fermentation. then decreased as fermentation progressed. However surface temperature was affected by external temperature after 10 days. Acetic acid content was not changed with 5 days by harvest stages, but that of boot stage was increased after 10 days. Butyric acid of boot stage was increased after 5 days. but that of heading stage was increased after 10 days. However lactic acid was increased from 1~2% to 6~8%. Lactic acid bacteria (LAB) of heading and flowering stages were highest at 5 days fermentation, and that of boot stage was highest at 10 days fermentation. The results of this study indicate that fermentation of round baled rye silage occur within 5 days. Therefore, any modification should be applied with an 5 days for high quality of round baled rye silage.