• 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.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.63-70
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• 2001

Changes in concentrations of dissolved oxygen, ammonia, nitrate, pH, Fe and Mn were monitored from the laboratory incubation of an benthic chamber. The extent of sedimentary organic carbon and nitrogen decomposition was quantified by applying the concentration data to the chemical reaction equations of early diagenesis. The patterns of the concentration changes, observed during the 237 hr long incubation experiment, made it possible to divide the entire experiment period into four characteristic sub-periods (0-9 hr, 9-45 hr, 45-141hr, 141-237 hr). C/N ratio, estimated for each sub-period, was 6.63, 1.49, 0.81 and 0.02, respectively. This sequential decrease in C/N ratio suggests that during the incubation experiment dissolved nitrogen species diffuse more out of the sediment than dissolved carbon species. Greater diffusion of nitrogen indicates the preferential decomposition of organic nitrogen during early diagenesis of sedimentary organic matter. Comparison of the concentration data (sedimentary organic carbon and nitrogen, porewater organic carbon and ammonia)between the sediment pre and post incubation also indicates the preferential decomposition of nitrogen during early diagenesis of sedimentary organic matter.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.2
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• pp.15-23
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• 2021

This study was conducted to evaluate the field application of the developed recommendation system in organic rice (Oriza sativa L.) paddy and to investigate the mineral nitrogen content in soil and rice productivity. According to the developed system, hairy vetch (HV), rye+rapeseed oil cake (R+OC), rapeseed oil cake (OC) for only basal fertilization (OC-B), OC for split application (OC-S), pig manure compost (PMC), and chemical fertilizer (CHM) were applied to paddy soil at the rate of 107~133 kg N/ha. Results were followed, unhulled rice yield of OC-S (111%), OC-B (110), R+OC (106), HV (101), and PMC (96) were no significantly different with CHM (100). Also there was positive correlation (R²=0.803^*) between unhulled rice yield and cumulative inorganic N in soil. For nitrogen use efficiency of rice, OC-B, OC-S, and R+OC were not significantly different with CHM. In conclusions, the developed organic materials use recommendation system was effective for organic rice productivity. It could be useful for organic farmer to apply the organic materials use recommendation system for rice.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.460-465
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• 2007

In this study, the removal characteristic of ammonia nitrogen and behavior of nitrogen was investigated using Leclercia adecarboxylata, which was derived from the culture contaminated by ammonia nitrogen of high concentration. The method of ammonia nitrogen removal was not biological nitrification and denitrification but elimination of nutrient salt with internal synthesis of microorganisms which use ammonia nitrogen as substrate. L. adecarboxylata(one of ammonia synthesis microorganisms) was highly activated and showed the most high removal efficiency in free salt condition but the removal efficiency decreased badly in salt concentration of more than 4%. About 80 mg/L of $NH_3-N$ was mostly removed within 20 hours and 500 mg/L of $NH_3-N$ showed less then removal efficiency of 50% because carbon source was not enough. However, ammonium nitrogen concentration was decreased again when the carbon source was inserted additionally thus, ammonium nitrogen removal efficiency by L. adecarboxylata, was related to amount of carbon source. pH decreased from 8.0 to 6.36 according to growth of L. adecarboxylata. Concentration of nitrite nitrogen and nitrate nitrogen did not increase and TKN concentration showed no variation while ammonia nitrogen was removed by L. adecarboxylata. In addition to, when content of protein in organic nitrogen was measured, protein was not detected at the beginning of microorganism synthesis but protein of 193.1 mg/L was detected after 48 hours. Hence, ammonium nitrogen was not decomposed as nitrate nitrogen and nitrite nitrogen but synthesized by L. adecarboxylata, which has excellent ability of nitrogen synthesis and can threat ammonia nitrogen of high concentration in wastewater.

• Korean Journal of Organic Agriculture
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• v.20 no.2
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• pp.211-220
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• 2012

This study was conducted to evaluate soil nutrient concentrations and N uptake efficiency of paddy rice as affected by nutrient sources from 2009 to 2011. The treatments included chemical fertilizer, compost, oilcake, oilcake 2X, hairy vetch, vetch+rye, and control. Nutrient applications were made at rates equivalent to approximately 90 kg of actual N per hectare. Oilcake had the lowest C:N ratio from the raw materials, but compost had the highest C:N ratio of 34:1. Soil pH and concentrations of C, N, Ca, and Mg were unaffected by nutrient source treatments. N uptake efficiency was the greatest for oilcake-treated rice compared to those treated by NPK, hairy vetch, and compost in 2009 and 2010. Composttreated rice had the greatest N uptake efficiency in 2011 when the high amount of precipitation occurred.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.368-371
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• 1983

Energy rich rice straw was subjected to biological processes involving the transformation of added nitrogen. A part of soil ammonium nitrogen was steadily exhausted when energy rich rice straw was decomposed. More vigorous transformation of added nitrogen ocurred during the first 5 days of incubation period than after 10 days of incubation period. Furthermore, transformation of added nitrogen occurred more markedly when more rice straw and less nitrogen were added. Remineralization of immobilized nitrogen did not take place in this experiment with 50 days of incubation.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.152-159
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• 2009

This study was carried out to investigate optimum application rate with mixed organic fertilizer for chemical fertilizer alternative where the paddy rice (Chucheong) was cultivated in clay loam of paddy field. The mixed organic fertilizer were applied at 0, 50, 100 and 150% levels of recommended nitrogen by soil testing plot compared with plot of chemical fertilizer (nitrogen, phosphate and potash), respectively. The ammonium nitrogen content in paddy soil and surface water of mixed organic fertilizer 100% plot were higher than chemical fertilizer plot. The absorbed amount of nitrogen and nitrogen use efficiency by rice plant in mixed organic fertilizer 100% plot were higher than chemical fertilizer plot. The number of tillers on rice at 30 days and 60 days after transplanting mixed organic fertilizer 100% plot were many more than chemical fertilizer plot. The milled rice yield of mixed organic fertilizer 100% plot was increased by 4% than chemical fertilizer plot. The optimum application rate of mixed organic fertilizer was as follows ; $OAR_{MOF}(Mg\;ha^{-1})=[(NAR_{ST}{\div}NC_{MOF}/1,000{\times}0.93)/1,000]$ ($OAR_{MOF}$ : Optimum application rate of mixed organic fertilizer, NARST : Nitrogen application rate($kg\;ha^{-1}$) by soil testing, $NC_{MOF}$ : Nitrogen content($g\;kg^{-1}$) of mixed organic fertilizer, and $0.93:124.3kg\;ha^{-1}/133.0kg\;ha^{-1}$, respectively).

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.375-379
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• 2007

폐비닐 여재(Synthetic Waste Polyethylene Media)를 적용한 부착성장식 공정의 유기물 및 질소${\cdot}$인 제거특성에 관한 Pilot Plant 실험 결과 다음과 같은 결론을 얻을 수 있었다. 1) 제거효율은 $RUNI1{\sim}3$에서 $COD_{cr}$ 91.4, 92.4, 93.9%, T-N 56.9, 61.4, 65.1%, T-P는 모든 단계에서 약 45%이상 제거되어 부하변동시에 강한 대처능력을 나타내었다. 2) BOD용적부하 $0.18{\sim}0.40kg/m^3{\cdot}d$, COD용적부하 $0.28{\sim}0.53kg/m^3{\cdot}d$, ${NH_4}^{+}-N$용적부하 $0.12kg/m^3{\cdot}d$을 나타내었다. 3) 도시하수 처리를 위한 생물학적 질소 및 인 제거공법을 본 여재를 이용하여 공정설계시 고려할 사항들과 적절한 대처방법을 다음과 같이 제시할 수 있다. - 1차 침전지에서 유기질소 및 유기인 농도가 높다면 유기질소 및 인 부하량을 감소시키기 위하여 1차 침전지를 설치하되 질소 및 인제거에 유리한 $BOD_5/T-N$, $BOD_5/T-P$를 유지할 수 있도록 체류시간을 1시간미만으로 설계하는 것이 경제적이라고 판단된다. 만일 유기질소와 유기인의 함량이 낮다면 1차 침전지는 제외하는 것이 유리할 것이다. - 여재의 배치는 폭기조에서 용존산소의 균일분포와 슬러지의 적정탈리를 위해 여재를 상하로 배치하거나 또는 여재끼리 일정 간격을 두어 배치하는 것이 바람직하다. 농촌에서의 처분이 문제시 되고 있는 폐비닐을 적용한 본 연구에서의 수처리특성은 기존 하수처리공정에서의 제거효율에 상응하는 처리특성을 나타내었다. 또한 폐비닐 처분의 문제를 해결할 수 있을뿐만 아니라 하수처리시에도 부하변동 등에 강한 대처능력을 나타내어 기존의 하수처리공정에 대체가능성을 나타내었다.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.19-30
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• 2019

Objective of this study was to develop an organic fertilizer utilizing domestic livestock horn meal and to investigate the application effect of rice and eggplant. The possibility of utilization of livestock horn meal as an organic resource to replace imported expeller cake fertilizer was examined. In order to select domestic organic resources with high nitrogen content, 8 kinds of organic matter such as chicken manure, fish meal, soybean meal, sesame meal, perilla meal, blood meal, livestock horn meal, and beer sludge were analyzed and organic resources with high nitrogen content were selected. In addition, the conditions for the production of organic fertilizers that can be used in organic agriculture were established by mixing of the rice husk biochar and the rice bran as the supplements with the raw materials for mixing ratios. The content of total nitrogen (T-N) in the livestock horn meal was 12.0 %, which was the next low in 13.5 % blood meal. The content of total nitrogen was 5.9 ~ 7.9 % in fish meal and oil cakes. Total nitrogen content of non-antibiotic chicken manure for organic farming was 3 % and nitrogen content in beer sludge was 3.5 %. Organic fertilizer was produced by using biochar, rice bran as a main ingredient of non-antibiotic chicken manure, livestock horn meal and beer sludge. Compared to nitrogen content (4.0 to 4.2 %) of imported expeller cake fertilizer (ECF), the nitrogen content of organic fertilizer utilizing domestic livestock horn meal is as high as 7.5 %. The developed organic fertilizer is met as Zn 400 mg/kg, Cu 120 mg/kg the quality of organic agricultural materials such as or less. To investigate the effect of fertilizer application on the crops, prototypes of developed organic fertilizer were used for the experiment under selected conditions. As a result of application the developed organic livestock horn meal fertilizer (LHMF) for cultivation of the rice and eggplant, the application quantity of the developed organic LHMF 100 % was decreased by 40 % compared to that of the mixed expeller cake fertilizer (MECF). The application of LHMF, which refers to the application rate corresponding to the nitrogen fertilization recommended by the soil test, was reduced by 40% compared to the application rate of MECF, but the same results were obtained in crop growth and yield. The selection of a new high concentration nitrogen source utilizing domestic organic resources and the development of organic fertilizer is the starting point of the research for substitution of imported ECF using domestic local resources at the present time that the spread of eco-friendly agriculture is becoming increasingly important. If it is expanded in the future, it is expected to contribute to the stable production of eco-friendly agricultural products.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.381-389
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• 2013

In order to study the effect of organic fertilizer on dry matter (DM) yield, nitrogen fixation and transfer from pea to barley, an experiment was carried out from May to June in 2008 in Incheon. A completely randomized block design with three replications was used for the experiment and one reference plot assigned each treatment for nitrogen fixation evaluation. Seeding mixture was 40kg barley and 80kg pea per ha. N rate of 40, 80 and 120kg/ha as organic fertilizer was applied at seeding. The equivalent of 1kg per ha as $(15NH_4)_2SO_4$ Solution at 99.8 atom N was applied to the plots ($30{\times}20cm$) at mid April. Forage was harvested from each plot in ripening stage at ground level and separated into barley and pea. Nitrogen fixation was 32.4%, 23.4% and 0% at three different organic N levels. Transfer rate were from 47.6% to 21.8% in difference method and 24.6% and 21.4% on $^{15}N$ dilution method. N Transfer amount were from 92.8kg/ha to 41.9kg/ha on difference method and 47.3kg in the 40kg N plots and 49.7kg in the 80kg N plots on $^{15}N$ dilution method but there was no N transfer in 120kg N organic fertilizer plots. Benefit from increased organic fertilizer was not clear in terms of nitrogen fixation and transfer from pea to barley in barley and pea mixtures.