• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.351-356
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• 2006

A long-term experiment was initiated in 1979 at Experiment Farm of Honam Agricultural Research Institute, to investigate the effects of continued use of organic matter (rice straw and compost) along with different levels of nitrogen fertilizer in rice cultivation. The soils of experimental plots is classified as Jeonbug series developed on Fluvio-marine deposits. The application rates of rice straw and compost were 5 Mg/ha/year and 10 Mg/ha/per year, respectively. The fertilizer N application rates per season were 0, 100, 150, 200, and 250 kg/ha. In 2002, after 24 years of experiment, the effect of different treatments on soil pH, characteristics soil organic matter, soil N and P were investigated. The results of the study is summarized as following. The continue use of organic matter tended to lower the soil pH, to increase organic matter and available phosphate contents. The rice straw tended to lower soil pH more than compost, while the effect of compost was greater in increasing soil organic matter and available soil P then rice straw. The application of organic matter resulted in the increase in total organic N in the soil. Such effect was greater in compost application than in rice straw application. In organic N, greatest was amino acid-N, followed by unidentifiable organic N. The least was amino sugar-N. The application of organic matter with and without nitrogen fertilizer affected the in organic fractions of P, particularly Fe-P and Al-P. The application of rice straw tended to increase Ca-P.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.53-61
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• 2016

The reaction of zero-valent iron (ZVI) with oxygen can produce reactive oxidants capable of oxidizing organic compounds. Thus, the aim of this study was to investigate the effect of pre-treatment on sludge solubilization by ZVI and aeration. The results demonstrated that the aeration pre-treatment with ZVI method was more effective than the only aeration for improving sludge solubilization, indicating that ZVI increased the extent of sludge solubilization. In addition, removal rate of $NH_3-N$ by ZVI and aeration was found to be 34%, while only aeration was 24%. Thus, ZVI and aeration can be employed as an efficient pre-treatment option to achieve higher sludge solubilization and decrease the toxic effect of $NH_3-N$ for sludge digestion.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.282-287
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• 1996

This study was conducted to identify the parameter better representing the nitrogen supply capacity of soils for the vegetable crops growing in vinylhouse. All the parameters showed significant positive correlation with the yield of chinese cabbage. The correlation coefficients were in the order of $NO{_3}^--N+NH{_4}^+-N(2M\;KCl)$ > $NO{_3}^--N(2M\;KCl)$ > OM > T-N > 0.01M $NaHCO_3$ > 0.01M $CaCl_2$ > $NH{_4}^+-N(2M\;KCl)$ > 6N HCl. Between the soil N and N absorbed by plant, the correlation coefficients were in the order of $NO{_3}^--N+NH{_4}^+-N(2M\;KCl)$ > $NO{_3}^--N(2M\;KCl)$ > 0.01M $NaHCO_3$ > $NH{_4}^+-N(2M\;KCl)$ > 0.01M $CaCl_2$ > OM > T-N > 6N HCl. The results of this study suggest that 2M KCl extractable inorganic N. 2M KCl extractable $NO{_3}^--N$ are recommendable parameters for the estimation of N supply capacity of the vinylhouse soils. The sum of soil $NO{_3}^--N$ and fertilizer nitrogen showed highly significant positive correlation with the yields of chinese cabbage and nitrogen absorbed by the plant, while negative correlation with the nitrogen use efficiency.

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.358-365
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• 2019

We measured the body composition, including bone mineral density (BMD) and food resource availability using dual energy X-ray absorptiometry and the carbon and nitrogen stable isotope ratios of body condition of 4 anuran species(Hyla japonica, Glandirana rugosa, Pelophylax nigromaculatus, Lithobates catesbeianus) in South Korea. Additionally, the carbon and nitrogen stable isotope ratios were employed to determine the food resource availability of anurans. We figured out the relationship between the body composition, including BMDs and food resource availability. The body composition and BMDs did not differ between male and female while there was difference among the species. Food resource availability and BMDs were the highest in L. catesbeianus, the lowest in H. japonica. BMDs tended to increase with higher food resource availability. Body composition and BMDs, which represent the body condition of an individual, can be used as an ecological indicator to assess the stability of the habitat of anurans.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.135-142
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• 1974

A study on the metabolism of the chemical companents of endosperm and enbryonic othans of ginseng seeds during their germination were inverstigated and the results of the changes in the contents of nitrogen conponds, carbohydrates, lipids and phosphorus conpounds are summarized as follow; 1. When a seeding grows to 5cm the fresh weight of the embryonic organ incerases 13 times compared with that of its ripened embryo veore germination and its dry weight increases 4.5 times. On the other hand, about 65% of the dry weight of the endosperm is lost. 2. During germinarion the total nitrogen content of a sedding (endosperm+embryonic organ) decreases and when the seeding grows to 5cm there is a loss of 10% of total nitrogen content. At this time, soluble nitrogen content amounts to 40~50% of the total nitrogen, a comparatively high content. 3. When theseeding grows to 5cm, the total phosphorus content decreases by 15%. During the germination period 70~75% of the total phosphorus is distributed in the embryonic orang and 25% of it is in endosperm.In the embryonic organ 35~50% of the acid soluble phosphorus is inorganic phosphorus and in the endisperm, 20~25% of the acid soluble phosphorus is inorganic phosphorus,75~80% of the organic phosphorus is contained in the endosperm. 4.One the seedling grew to 2~3cm, carbohydrates such as soluble sugars,reducong sugars,nonreducong sugars, and crude starch interconverted remarkably. 5.After stratification (just before germination) the lipid content of the endosperm is about 54% of the total weight and lipid content of the embryo is about 61%. During germination 6.81mg of the fat contained in the endosperm per seed decreases to 4.13mg while the change of fat content in the embryonic organ is not so great.

• Applied Biological Chemistry
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• v.7
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• pp.79-84
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• 1966

1. In order to elucidate the differences between varieties of Korean soybean, forty-nine subjects were examined for their chemical constituents. Their proportions varied considerably with the differences in variety. The moisture varied from 10.93% to 12.57%(aver. 11.95%), protein; 33.79% to 47.00%(aver. 39.8%) crude fat; from 16.32% to 24.79%(aver. 19.2%), crude fiber; from 3.03% to 5.57%(aver. 3.98%), ash; from 3.95% to 5.23%(aver. 4.6%) and nitrogen free-extracts (earbohydrates); from 16.58% to 26,81% (aver. 20.57%) Chemical composition of soybean was affected by the varieties as well as their localities of growth. 2. Of the total protein, 33.26% based on the soybean meal was soluble protein and 1.94% insoluble protein in average.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1018-1022
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• 2002

Effect of nitric oxide (NO) treatment on physiology and quality characteristics of peaches (Prunus persica L. Batsch) was determined. Peaches were treated for 4 hr with NO (0, 10, 100 ppm) gas under oxygen-free atmosphere at $10^{\circ}C$, packaged with 0.05-mm LDPE film, and stored at $10^{\circ}C$ for 15 days. Treatment with 100 ppm NO reduced the ethylene production and the loss of flesh firmness in peaches, but did not affect soluble solids, titratable acidity, and surface color. Oxygen-free atmosphere induced the reduction of respiration rate and ethylene production. Modified atmosphere packaging retarded the loss of flesh firmness and surface greenness, but decreased soluble solids and titratable acidity regardless of NO treatment.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.04a
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• pp.98.4-98
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• 1978

방선균에서 RNA 분해효소력이 강한 균주를 토양으로부터 선별하여 이 균주의 RNA 분해산물을 검토하고 부산물로서 항생물질의 생성을 조사하였다. 먼저 동시 생성 생육조건을 검토한 결과, 유기 질소원으로서 soybean meal 1.5%, 무기 질소원으로서는 $KNO_3$ 0.05% 첨가하였을 때 효과가 있었고, 탄소원으로서는 가용성 전분 2% 첨가시가 조건이 좋았다. 무기염류를 배지에 첨가하였을 때 별 다른 영향이 없었고 오히려 $CuSO_4를$ 가하였을 때는 저해를 보였다. 최초 pH가 7.0, 배양 2일째에 균체증식, 효소생산 및 항생물질의 생산이 최대를 나타내었다.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.6-11
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• 1980

In order to find the interaction between phosphorus and nitrogen effects during low temperature treatment, experiments of rice planted late at low water temperature were conducted and the following results were obtained. As the application of phosphorus increased, the soluble nitrogen content in the rice plants was decreased, while the degree of ripening was improved, especially when the application of nitrogen increased. When the heading was promoted due to high temperature, degree of ripening was improved. The number of spikelets increased due to the increased application of nitrogen fertilizers, and then The effects of phosphorus application on the improvement of ripening was less apparent.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.172-183
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• 1976

RNA, DNA and other phosphorus fractions were determined in the leaf and root of soybean plants different in phosphorus sensitivity grown in $NH_4-N,\;NO_3-N$ and urea medium. The phosphorus sensitive cultivars contained higher ASIP (acid soluble inorganic phosphorus) than the tolerant cultivars with all nitrogen sources. ASIP was highest in the urea treated plants and lowest in the nitrate treated plants. Total phosphorus content was mostly affected with increase in ASIP. When ASIP increased, acid solsuble organic phosphorus(ASOP), phospholipids (L-P), RNA-P, residual phosphorus (R-P) tended to increase, while DNA-P showed little change. The percent RNA-P or DNA-P of total phosphorus in the nitrate treated plant was twice that in the ammonium treated plant, which were also higher in tolerant cultivars regardless of nitrogen sources. The percent ASOP in total acid soluble phosphorus $(ASOP/ASP{\times}100)$ decreased as phosphorus sensitivity decreased. Indications are that phosphorus sensitivity depends on the relative sizes of phosphorus metabolic pools. Total dry matter yield was negatively correlated with total phosphorus (r=0.84 significant at 0.01P), ASIP (0.84 significant at 0.01P) and residual phosphorus (0.69 significant at 0.05P). ASOP showed positive correlation with L-P, RNA-P and DNA-P but negative with R-P. RNA-P was significanly correlated only with L-P (0.63 at P=0.01). There was significant interaction (0.01) among nitrogen sources, cultivars and phosphorus metabolic pools. Phosphorus sensitivity and ammonium toxicity appear to be same in view of energy metabolism, that is, the former inhibits the conversion of ATP to ADP (energy releasing) through phosphate potential while the latter inhibits ATP formation (energy storing).