• 한국수산과학회지
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• 제29권6호
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• pp.779-786
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• 1996

The main purpose of this study was to estimate the role of dissolved inorganic nitrogen (DIN) released from sediment and denitrification process in sediment on the nitrogen budget of Hiroshima Bay by means of collecting data on distributions and budgets of nitrogen and phosphorus in the bay, DIN fluxes across sediment-water interface and denitrification rates in the sediments of the same area. The TN : TP and DIN:DIP atomic ratios of the discharged freshwater were about 26 and 21, respectively. The standing stocks in the seawater of the TN : TP atomic ratio varied from 8 to 14 with an annual mean value of 11, while the DIN : DIP atomic ratio varied from 10 to 15 with an annual mean value of 12 in the bay. The residence time of nitrogen and phosphorus were estimated to be about 109 days and 200 days in the bay, respectively. The proportion of DIN released from sediment and denitrification rate to the loading of total nitrogen into Hiroshima Bay were $45\%\;(37\~82\%)\;and\;13\%(0.0\~37\%)$, respectively, and the amount of nitrogen through denitrification process was 6.5 times larger than the outflow of nitrogen from the bay. The results show that DIN released from sediment and denitrification process in sediment play important roles on the nitrogen budget in Hiroshima Bay.

• 한국농공학회지
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• 제44권3호
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• pp.136-145
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• 2002

Monitoring data from agricultural reservoirs throughout the country were analyzed to evaluate the limiting factor fur algal growth and relationships between Chl-a, total phosphorus (TP), and total nitrogen (TN). Total 394 reservoirs ranging from below 500 ㎥ to over 50 million ㎥ in storage volume were monitored from 1990 to 2000 with respect to TP, W, Chl-a, and their annual mean values were used fur the analysis. Based on N/P ratio, the dominant limiting factor for algal growth was turned out to be phosphorus in agricultural reservoirs (about 83%). Therefore, the proper managements of phosphorus in the agricultural watershed appear to be crucial to prevent excessive on algal growth. The effects of phosphorus and nitrogen ware most eminent during the summer period. And the effect of nutrients on the algal biomass (Chl-a) development appeared to be greater in smaller the reservoirs than in larger ones. Generally, Chl-a and TP demonstrated a close relationship while that of Chl-a and TN showed less correlationship. Chl-a and chemical oxygen demand (COD) also showed a good relationship. Beth ratios of Chl-a / TP and Chl-a / COD relationships were within the range of literature values. Quantitative analysis of TP and COD is relatively convenient compared to that of Chl-a, and the relationship between TP and COD and Chl-a from this study could be used beneficially for water quality management of agricultural reservoirs and related water quality modeling.

• 한국수산과학회지
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• 제49권2호
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• pp.241-246
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• 2016

A filamentous green alga Cladophora vadorum (Areschoug) Kützing, bloomed at Shangrok Beach, Buan, Republic of Korea, in September 2015. This alga is currently distributed worldwide. Concentrations of total nitrogen (TN), total phosphorus (TP), dissolved inorganic nitrogen (DIN), and dissolved inorganic phosphorus (DIP) were analyzed in the bloom area and compared to those of other areas in the vicinity. DIN and DIP concentrations were similar to those of other areas. However, TN and TP were as much as six and ten times higher than in other areas, respectively. As in other Cladophora species, the bloom of C. vadorum at Shangrok Beach in 2015 appears to have depended on the TP concentration in the seawater. This suggests that blooms in the area can be controlled by reducing TP.

• 한국초지조사료학회지
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• 제20권1호
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• pp.31-40
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• 2000

This study was conducted to investigate the effects of application levels of swine manure fermented with sawdust(SMFS) and degree of the slope on productivity of corn, and nitrogen and organic matter runoff in corn cultivation soil. Main plots were consisted of the degree of slope, such as 0, 5 and 10, and the subplots consisted of application levels of SMFS, such as control, 200kgNha and 400kgNha. Lysimeter was constructed with 0.33m width, 3m length and 0.4m height. Dry matter(DM) yields of corn decreased as the slope increased but there was no significant differences between the degree of the slope. DM yields increased significantly as application levels of SMFS increased (pc0.05). DM yields decreased according to continuous cultivation of corn. Total nitrogen(TN) contents of the whole corn decreased as the slope increased(p<0.05). TN content in SMFS treatments was higher than that of non-SMFS treatment but there was no significantly different between SMFS treatments. TN yields decreased significantly as the slope and the application level of SMFS increased(p<0.05). Nitrogen and organic matter yields in the runoff waters increased as the slope and application levels of SMFS increased. The runoff of nitrogen and organic matter was more affected by the increase of the slope than application levels of SMFS. (Key words : Corn, Runoff, Swine manure, Degree of slope, Lysimeter)

• 유기물자원화
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• 제23권4호
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• pp.21-31
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• 2015

본 연구는 거대억새(Miscanthus sacchariflorus var Geode Uksae-1)와 갈대(Phragmites australis)를 활용하여 돈분뇨 처리수 유래 영양염류(질소 및 인) 제거를 정량적으로 분석하고 생산된 바이오매스의 총 에너지가와 바이오메탄 잠재성 분석을 목적으로 수행되었다. 식물들은 일반토양과 사질토 또는 일반토양, 사질토 및 바이오세라믹의 혼합 여재로 채워진 용기에서 다루어졌다. 사용된 돈분뇨 처리수의 총질소와 총인함량은 각각 222.78 mg/L 과 66.11 mg/L에 해당하였다. 총질소와 총인 모두 바이오세라믹 첨가구에서 높은 제거율을 보였다. 거대억새에서 총질소 제거율이 가장 높게 나타났다(96.14%). 하지만 식물체의 원소분석 결과 갈대의 질소함량이 거대억새보다 더 높게 나타나 갈대의 질소흡착력이 더 뛰어난 것으로 판단된다. 반면 가장 높은 총 인 제거율을 보인 처리구는 갈대로 98.12%의 값을 보였다. 식물체 셀룰로스 함량은 일반토양 처리구보다 바이오세라믹 처리구에서 약 3~6% 더 높게 나타나 바이오세라믹은 식물섬유 형성에 영향을 미치는 것으로 사료된다. 본 연구에서 생산된 바이오매스의 바이오메탄 잠재성 분석결과 약 $57.01{\sim}99.25L-CH_4/kg$ VS의 값을 보였다. 리그닌은 식물의 바이오매스 분해를 방해하는 요소로 일반토양-사질토 여재를 사용한 갈대 처리구에서 가장 높게 나타나 메탄 생산력이 떨어지는 것으로 판단된다.

• 한국초지조사료학회지
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• 제20권2호
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• pp.123-130
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• 2000

This study was carried out to examine the effects of animal manure on efficiency of the nitrogen utilization of silage corn (Zea mays L.) and soil fertility. The experiment was conducted on the field plot at Gongiam, Kwangju, Kyunggi-Do for 3 years, from 1996 to 1998, and arranged in split-plot design with three replications. The main plots were two kinds of composts such as swine manure fermented with sawdust (SMFWS) and swine manure fermented without sawdust (SMF). Subplots were the nitrogen fertilization rate (0, 100, 200, 300 and 400kgNhalyear). The nitrogen (N) yield increased as the nitrogen fertilization rate increased up to a rate of 300 kg Nha, but decreased at rate of 400 kg Nlha. Nitrogen yield in SMF treatments was higher than that of SMFWS treatments. But there were no significant differences between SMFWS and SMF treatments. Organic matter (OM) content of the soils in SMFWS was higher than that of SMF, &d was not significantly different between SMFWS and SMF treatments. OM content increased with increasing the nitrogen fertilization rate. Total nitrogen (TN) content of the soils increased as the nitrogen fertilization rate increased. No difference of TN content was found between SMFWS and SMF treatments. (Key words : Swine manure, Compost, Corn, Sawdust, Nutritive value)

• 한국환경과학회지
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• 제18권7호
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• pp.811-817
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• 2009

To determine changes in nitrogen contents and optimal rates as N fertilizer, we investigated nitrogen characteristics in the slurry in the respond to the application of 0, 0.5, and 1 g of ferrous sulfate or alum /25g of dairy slurry. Additions of ferrous sulfate or alum increase total nitrogen, inorganic nitrogen, available nitrogen, and predicted available nitrogen contents in dairy slurry, resulting in reduction in pH. The best results were found in the treatment with 0.5 g of ferrous sulfate or alum /25 g of dairy slurry. In conclusion, the use of ferrous sulfate or alum as on-farm amendment to dairy slurry should be represented an alternative to improve N in dairy slurry.

• 한국환경과학회지
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• 제12권1호
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• pp.55-61
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• 2003

This study was carried out to obtain the operating characteristics of SMMIAR process for biological nitrogenㆍphosphorus removal. SMMIAR was operated at HLR(Hydraulic loading rate) of 39.6, 52.8, 63.4 and 79.2 $\ell$/$m^2$/d respectively and the operating parameters such as intermittent aeration time ratio of aerobic/anoxic, DO and microorganism concentration were changed to confirm the optimum operating condition. The concentrations of the wastewater BOD, TN(Total nitrogen) and TP(Total phosphorus) were 150, 30 and 7.5mg/$\ell$ respectively. Achieving better removal efficiencies of BOD, TN and TP up to 90, 85.4 and 95.4% respectively, we must keep in operation condition of SMMIAR by 0.75 of time ratio of aerobic/anoxic and by minimum 45 minutes of oxic period simultaneously.

• 한국농공학회논문집
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• 제47권2호
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• pp.99-110
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• 2005

Characteristics of concentrations of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) pollutant in percolated water at four paddy field sites (Soro, Odong, Munui, and Boeun) were investigated by a nonparametric test. Percolation rate measurement and percolated water sampling were taken during irrigation periods at $5{\sim}10$ day intervals. The normality of percolation rate and pollutant concentrations were examined using histogram, boxplot, and the Kolmogorov-Smirnov (K-S) test. Pollutant concentrations in percolated water showed positively skewed distribution. The median concentrations of pollutant were 1.91 mg/L for TN, 0.021 mg/L for TP, and 6.6 mg/L for COD, which were lower than its arithmetic mean concentrations by $35\%$ for TN, $36\%$ for TP, and $13\%$ for COD. The median concentrations of TN and TP differed significantly among sample sites according to the Kruskal-Wallis test. However, median concentrations were not significantly different among month except for TN and TP of Soro and COD of Odong. The percolation load of pollutants during irrigation periods in the study area were estimated at $3.12{\sim}7.75\;kg/ha$ for TN, $0.033{\sim}0.155\;kg/ha$ for TP, and 10.7 kg/ha for COD, which were much lower than respective values reported in Japan.

• 한국토양비료학회지
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• 제50권2호
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• pp.100-105
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• 2017

Various methods for assessing soil total nitrogen (TN) and inorganic N content have been developed to manage nutrient and to understand N cycle in soil. This paper address the technical procedures in arable soil samples to conduct soil sampling, sample preparation, and measuring total N and inorganic N. Among various methods for measuring soil total nitrogen contents, Kjeldahl distillation and Indophenol blue method have widely used due to reliability and economic advances. Also, two methods can analyze more samples at the same time compared with other nitrogen measuring methods. For evaluating inorganic N content, mainly in forms of nitrate-N ($NO_3{^-}-N$) and ammonium-N ($NH_4{^+}-N$), extraction with a single reagent such as 2M KCl has been employed, followed by Kjeldahl distillation or indophenol blue methods.