• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.67-68
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• 2001

돈분발효퇴와 포도주 부산물의 질소 무기화 및 질산화 과정을 구명하기 위해 시설 내 고추생육시기에 토층별 암모늄태 및 질산태 질소함량을 조사하였다. 질소무기화 및 질산화는 심토층보다 표토층에서 높게 나타났다. 생육전반에 걸쳐 총 질소 무기화 및 질산화율은 처리간에 다양하였지만, 전반적으로 총 질소 무기화는 정식후 90일 까지 증가하였지만 그 이후로는 감소하였다. 표토층에 있어 최고 질소 무기화 및 질산화는 정식후 90일에 T4(포도주부산물 400kg/10a＋돈분발효퇴비 1,000kg/10a)에서 관측되었다. 가장 높은 질소 무기화는 정식후 30일에 대조구에서 272.5mg/kg과 정식 후 90일에 T4(포도주부산물 400kg/10a＋돈분발효퇴비 1,000kg/10a)에서 843.4mg/kg으로 나타났다. 또한 질산화는 T4(포도주부산물 400kg/10a＋돈분발효퇴비 1,000kg/10a)에서 정식 후 90일에 872.2mg/kg으로 가장 높게 나타났다. 15-30cm 토층의 질산화 현상은 질소 무기화와는 다르게 나타났는데 질소 무기화는 대체로 90일에 증가한 반면 질산화는 90일에 감소하는 경향을 나타내었다. 마지막 조사시기인 정식 후 180일에는 급격히 감소하는 현상을 보였는데 고추 생육에 따라 양분 흡수로 암모늄태질소 및 질산태질소가 감소되었다. 0-15cm 토층, 15-30cm 토층의 질소무기화 및 질산화에서 T4(포도주부산물 400kg/10a＋돈분발효퇴비 1,000kg/10a)의 15-30cm 토층 질산화가 낮게 나타났다.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.219-224
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• 2001

This experiment was conducted to evaluate net mineralization and nitrification in rain shelter soil incorporated with wine sludge. Net mineralization and nitrification rates varied among treatments during pepper growing periods. In general, net mineralization increased up to 90 days after transplanting before its decrease during the rest growing periods. Maximum net mineralization and nitrification in upper 0-15 cm layer soil were observed in T4 at 90 days after transplanting. The greatest amount of mineralization in upper layer soil was 272.5 mg.kg$^{-1}$ at 30 days in the control and 843.3 mg.kg$^{-1}$ at 90 days after transplanting in T4. Overall, both net mineralization and net nitrification were greater in the upper layer soil than in the lower 15-30 cm layer soil.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.262-268
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• 2019

BACKGROUND: To investigate mineralization characteristics of organic resources in the soil, five materials (rice straw, cow manure sawdust compost, microorganism compost, mixed oil-cake, and amino acid fertilizer) were treated according to the nitrogen content, and an indoor incubation experiment was conducted for 128 days. The results of this analysis were applied to determine the nitrogen mineralization pattern of these organic resources. METHODS AND RESULTS: During the constant temperature incubation period, the nitrogen net mineralization rate of the organic resources was the highest in the amino acid fertilizer with the highest nitrogen content, and the lowest in the rice straw with the lowest nitrogen content. A positive correlation (0.96) was observed between the potential nitrogen mineralization rate and total nitrogen content. The mineralization rate constant, k, was negatively correlated with the organic matter (-0.96) and carbon content (-0.97). The nitrogen mineralization rate during the first cropping season, as estimated by the model, was 6.6%, 11.6%, 30.9%, 70.7%, and 81.0% for the rice straw, the cow manure sawdust compost, the microorganism compost, the mixed oil-cake, and the amino acid fertilizer, respectively. CONCLUSION: The nitrogen mineralization rate varies depending on the type of organic resources or the nitrogen content; thus, it can be used as an index for determining the nitrogen supply characteristics of the organic resource. Organic resources such as compost with low nitrogen content or those undergoing fermentation contain organic nitrogen. Organic nitrogen is stabilized during the composting process. Therefore, as the nitrogen mineralization rate of these resources is lower than that of non-fermented organic resources, it is desirable to use the fermented organic materials only to improve soil physical properties rather than to supply nutrients for the required amount of fertilizer.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.3
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• pp.33-40
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• 2014

This study were conducted to evaluate the N mineralization and nitrification rates and to estimate the losses of total carbon and nitrogen by runoff water in soils cooperated with organic composts and bio-char during corn cultivation. For the experiment, the soil texture used in this study was clay loam, and application rates of chemical fertilizer and bio-char were $230-107-190kg\;ha^{-1}$($N-P_2O_5-K_2O$) as recommended amount after soil test and 0.2% to soil weight. The soil samples were periodically taken at every 15 day intervals during the experimental periods. The treatments were consisted of cow compost, pig compost, swine digestate from aerobic digestion system, and their bio-char cooperation. For N mineralization and nitrification rates, it was shown that there were generally low in the soil cooperated with bio-char as compared to the only application plots of different organic composts except for 47 days after sowing. Also, they were observed to be highest in the application plot of swine digestate from aerobic digestion system. For loss of total carbon by run-off water, it was ranged from 1.5 to $3.0kg\;ha^{-1}$ in the different organic compost treatment plots. However, Loss of total carbon with bio-char could be reduced at $0.4kg\;ha^{-1}$ in PC treatment plot. Also, with application of bio-char, total nitrogen was estimated to be reduced at 4.2 (15.1%) and $3.8(11.8%)kg\;ha^{-1}$ in application plots of pig compost and swine aerobic digestate, respectively.

• Applied Biological Chemistry
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• v.45 no.3
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• pp.134-137
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• 2002

Approximate composition and physicochemical properties of 2 cultivars of plum (P. salicina), Humoosa and Daeseok, were examined. The contents of crude fat and N-free extract were different between 2 cultivars. Total mineral contents of Humoosa and Daeseok were 30.00 and 17.99% respectively, and S, K and Mg were major minerals in both cultivars. Humoosa has higher contents of fructose whereas Daeseok has higher contents of sucrose. Major organic acid in flesh was malic acid. While citric acid was major organic acid in the peel of Humoosa, malic acid was major in the peel of Daeseok. Glutamic acid, alanine and ${\gamma}-aminoisobutyric$ acid were major free amino acid in both cultivars and their total contents were about the same.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.21-26
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• 2002

The behavior of the biological water treatment process on start-up operation was evaluated in the integrated recirculating aquaculture system consisting of a double drain type rearing tank ($2.5 m^3$), a sedimentation tank, a floating bead filter, a foam separator and a rotating biological contactor. A system was stocked with nile tilapia (Oreochromis niloticus) at an initial rearing density of $2\%$ for 2 weeks for acclimated rotating biological contactor. The total ammonia nitrogen (TAN) level increased to $13.6 g/m^3$ on day 4 after adding feed and was decreased to $0.3 g/m^3$ on day 7. The total suspended solid was completely removed during overall experimental period.

• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.9-15
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• 2011

BACKGROUND: This study was conducted to evaluate the effects of the fertilizer sources and ground cover mulches on nutrient release, growth, and photosynthesis in small one-year-old apple (Malus ${\times}$ domestica Borkh.) trees in controlled conditions. METHODS AND RESULTS: Treatments included no fertilizer (NF), commercial organic fertilizer (CF), and poultry litter (PL) for fertilizer treatments, and wood chips (WC), shredded paper (SP), green compost (GC), and grass clippings (GR) for cover mulch treatments. All treatments were applied proportionally based on the volume ratio equivalent to the soil. CF, PL, and GR treatments that had optimum carbon (C) and nitrogen (N) ratios (less than 30:1) for N mineralization through the microbes released the greatest $NH_4^+$ concentrations in the pot media at 90 days after the treatments, but GC mulch with the optimum C:N ratio did not. CF-, PL- and GR-treated plants had the largest leaf area, thickest stem diameter, longest shoot extension, and greater dry matter production. CONCLUSION(s): CF and PL showed an suitable organic nutrient source for improving plant growth in an orchard. Interestingly, GR also could be a nutrient source for tree growth, if vegetation competition is controlled by maintaining vegetation height and recycling enough grass clippings to the soil in an orchard.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.87-92
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• 1990

To produce ergosterol Saccharomyces toke KBA No. 6 was used and various factors related to ergosterol accumulation were investigated. The most effective inorganic nitrogen source was ammonium chloride and 3.50 % of ergosterol was accumulated in the cell when the C/N ratio was 200/1. When Tween 80 and potassium nitrite were used simultaneously, ergosterol content and total amount of ergosterol were increased by 56 % and 45 %, respectively, compared to their control in which 0.2 % of Tween 80 and 0.1 % of potassium nitrite were used. Under the optimum conditions, ergosterol content increased from 1.73 % to 5.3 % and the total amount of ergosterol was increased from 65.2 mg/l to 135.15 mg/l.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.198-206
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• 1995

The objective of this study was to determine the rate of nitrogen mineralization at clearcut and uncut in oak(Quercus rubra L.) and pine(Pinus resinosa Ait.) stands. The study sites were located in northern Lower Michigan, U.S.A. Nitrogen mineralization rates in the top 15cm of mineral soil were examined during the 1991 and 1992 growing seasons(May-October) using an in situ buried tag technique. diet nitrogen mineralization in oak stands over the course of both growing seasons was 67kg/ha in the clearcut and 30kg/ha in the uncut stands. In contrast, net nitrogen mineralization in pine stands was 27kg/ha and 13kg/ha for the same treatments. Total net nitrogen mineralization rates were always higher in oak stands than in pine stands. Extractable $NO_3^-$ before and after one month soil incubation in both oak and pine stands was generally not detectable in the uncut stands, but in the pine clearcut treatment(nitrification over the course of both growing seasons : 3.3kg/ha). The results indicated that : 1) substantial increases in the amount of available soil nitrogen occurred following clearcuts in both stands : and 2) the loin rates of nitrification may be an important mechanism for retention of nitrogen in both oak and pine stands.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.1
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• pp.38-46
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• 2012

This study carried out current status, characteristics, and problems of coastal environment management on semi-enclosed Masan Bay in Korea and suggests cost-effective and eco-friendly water quality management policy. The pollutants from terrestrial sources into the Bay have apparently environmental pollution problems, such as eutrophication, red tide, and hypoxia. The carrying capacity of the Bay is estimated by hydrodynamic model and ecosystem model, material circulation including bivalve in ecosystem is analyzed by the growth model of bivalve. The resulting reduction in the input load was found to be 50~90%, which is unrealistic. When the efficiency of water quality improvement through bivalve farming was assessed based on the autochthonous COD, 30.7% of the total COD was allochthonous COD and 69.3% was autochthonous COD. The overall autochthonous COD reduction rate by bivalve aquaculture farm was found to be about 6.7%. This study indicate that bivalve farming is about 31% less expensive than advanced treatment facilities that remove both nitrogen and phosphorous.