• 한국환경농학회지
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• 제32권1호
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• pp.9-16
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• 2013

주암호내 복내 저수구역에서 서식하는 자생식물체들이 침수시 주암호 수질에 미치는 영향을 파악하기 위하여 복내 저수구역이 침수되기 전인 2010년 8월의 영양염류(질소 및 인) 최대 흡수량과 침수 후 다시 침수이전 수위로 회복된 2011년 2월에 남은 식생의 영양염류 잔존량 차이를 이용하여 산술적인 영양염류 용출량을 산정하였다. 2010년 8월에 침수되기전 복내 저수구역내 식생의 면적은 987,872 $m^2$이었다. 침수전인 2010년 8월에 복내 저수구역내 식생의 분포면적별 T-N의 흡수량은 물억새가 247 kg/total reservoir area, 이삭사초가 11,340 kg/total reservoir area로 분포면적이 넓은 이삭사초의 T-N 흡수량이 물억새에 비해 많았으며, T-P의 흡수량도 1,231 kg/total reservoir area로 이삭사초가 가장 많았다. 침수 후 2011년 2월에 조사된 상부지역 물억새의 T-N 및 T-P의 잔존량은 각각 34 및 11 kg/total reservoir area로 침수 전에 비해 감소하였고, 이삭사초의 T-N 및 T-P의 잔존량은 각각 491 및 68 kg/total reservoir area로 물억새와 비슷한 경향으로 침수 전에 비해 감소하였다. 이상의 결과를 종합하여 복내 저수구역내 식생의 T-N 및 T-P의 총 용출량을 산정한 결과 T-N 용출량은 복내 저수구역 총 식생면적(987,872 $m^2$)당 12,212 kg, T-P 용출량은 총 식생면적당 1,324 kg이었다. 따라서 복내 저수구역내 자생식물은 침수시 수중에서 분해되면서 식물체내 질소 및 인이 용출되어 주암호의 수질오염을 가중시킬 수 있는 한 요인이 될 수 있으므로 호소내 수질개선을 위해서는 저수구역내 식물체의 관리방안이 필요할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.203-208
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• 1999

An 8 week feeding trial was conducted with 864 ISA Brown laying hens, 48 weeks old, to determine if microbial phytase $(Natuphos^{(R)})$ supplementation can reduce non-phytate phosphorus (NPP) level in laying diets. The experiment consisted of four dietary treatments: T1, control diet with 0.26% NPP (0.55% total P) wand no supplementary phytase; T2, 0.21% NPP (0.50% total P) diet with 250 U of phytase/kg of diet; T3, 0.16% NPP (0.45% total P) diet with 250 U of phytase/kg of diet; and T4, 0.11% NPP (0.40% total P) diet with 250 U of phytase/kg of diet. T3 showed the highest egg production and egg weight and the lowest feed conversion while T4 gave the lowest egg production and the highest feed conversion and mortality. Daily feed consumption ranged from 130.4 g (T4) to 132.7 g (T2). T1 and T2 were not significantly different in the production parameters. Eggshell strength, egg specific gravity, and eggshell thickness were not significantly different among treatments. However, broken egg ratio was significantly lower in T2 and T4 than in T1. Retentions of Ca, P, Mg, and Cu were greater in phytase supplemented treatments (T2, T3, and T4) than the control (T1), and those in T3 and T4 were greater than in T2. Excretions of P in phytase supplemented treatments (T2, T3, and T4) were significantly (p<0.05) smaller than in T1 but excretions of N were not significantly different among the treatments. Contents of ash in tibiae were not significantly affected by treatments, but contents of Ca, P, Mg, and Zn was increased and that of Cu decreased by phytase supplementation. It is concluded that the NPP concentration in the diet of Brown layers consuming about 130 g/d of feed can be safely lowered from 0.26% (0.55% total P) to 0.16% (0.45% total P). The excretion of P was reduced by the inclusion of 250 U phytase/kg of diet.

• 한국환경과학회지
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• 제22권3호
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• pp.379-383
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• 2013

This study was conducted to investigate the changes in nitrogen and soluble reactive phosphorus(SRP) contents from hanwoo manure using probiotics to feed and manure additives during 5 weeks. A total of 45 hanwoo(24 months old) with averaging $580{\pm}20$ kg in weight were randomly assigned to 3 dietary treatments with 3 replicates per treatment(5 hanwoo per pen, $5{\times}8m$). The treatment were supplemented, control, T1(10 kg roughage + 2 kg concentrate(2% probiotics as-fed basis)), and T2(10 kg roughage + 2 kg concentrate(2% probiotics as-fed basis) + 7 kg probiotics on the surface of hanwoo manure (top-dressing)). During the experimental period, there were statistically significant differences(P<0.05) in pH values at 3 and 5 weeks; TN contents at 5 weeks; and SRP contents at 5 weeks in all treatments. Adding probiotics to feed or feed and manure increased manure pH in comparison with controls. As time increased, changes in TN contents decreased in the order: T2 > Control > T1. Especially, the reduction in SRP contents in all treatments at 5 weeks was in following order: T1 > T2 > Control. This result suggests that it is possible to make efficient use of probiotics as feed and manure additives for reducing environmental pollution or to provide fundamental information on livestock managements to producers.

• 한국수자원학회논문집
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• 제36권5호
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• pp.787-797
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• 2003

산지계류수에서의 T-N(총질소), T-P(총인) 및 COD(화학적산소요구량)의 농도와 유출부하의 변화를 파악하고 산림의 수질정화기능을 평가하였다. 충청북도에 있는 시험유역은 면적이 92.5 ha이며 59%의 혼효림과 30%의 침엽수림으로 구성되어 있다. 시험유역의 말단에서 평상시는 10일 간격으로 또한, 1개의 강우사상에 대하여 2-6 시간 간격으로 계류수의 유량과 농도를 1년간 측정하였다. 강우시의 평균농도는 COD만이 유의적인 수준(p<0.05)에서 평상시의 농도보다 높게 나타났다. T-N과 T-P의 평균농도는 식생생육기(5-10 월)가 식생 휴지기(11-4 월) 보다 낮게 나타났는데, 이는 식물에 의한 영양염류 흡수와 토양의 온도상승에 따른 미생물의 활동이 증가하기 때문으로 생각된다. 연간유출부하에 대한 강수시 유출부하의 비는 T-N이 87%, T-P가 83%, COD가 87%로서 연간유출부하 중 강우시의 유출부하가 매우 높게 나타났다. 시험유역의 오염부하 원단위는 T-N이 5.9 kg/ha $\cdot$ yr, T-P가 0.15 kg/ha $\cdot$ yr, COD가 23.9 kg/ha $\cdot$ yr로 산정되었다. 또한, 시험유역에 의한 T-N, T-P 및 COD의 연간제거율은 각각 24, 58, 66%로 나타나, 산림유역이 수질정화기능을 발휘하고 있는 것으로 판단된다.

• 환경생물
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• 제27권3호
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• pp.306-313
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• 2009

In the Upo wetland, physico-chemical factors were observed during the period from March 2005 to December 2007 on a monthly basis. In the Upo wetland, water temperatures ranged $3.4{\sim}34.5^{\circ}C$. Conductivities were in the range of 133~806 ${\mu}S\;cm^{-1}$, which showed about 140 ${\mu}S\;cm^{-1}$ below in comparison with the precedent studies. The pH levels were between 6.7~9.1 with lower level in summertime. The dissolved oxygens were between 0.06~18.23 mg $L^{-1}$. COD ranged 4.9~20.8 mg $L^{-1}$, and showed a tendency to decrease every year. Nitrogen nutrients such as nitrate nitrogen ($NO_3-N$), ammonia nitrogen ($NH_3-N$) and total nitrogen (T-P) showed that they were generally decreased in comparison with those in the precedent studies. However the total nitrogen (T-N) is still considerably higher than the standard concentration level of eutrophication and algal blooming. Phosphate phosphorus ($PO_4-P$) and total phosphorus (T-P) were also shown as to be reduced considerably comparing with the values in the precedent studies. However, It was found out that total phosphorus (T-P) was dissolved over the criteria concentration of eutrophication. The average of TN/TP ratio was 18 in the Upo wetland, which proved that phosphorus was the limiting factor to the growth of phytoplankton in the Upo wetland. The chl-$\alpha$ was the highest in wintertime and the lowest in summertime, and especially in 2006 summer when the cyanobacterial bloom developed, it showed extremely high concentration.

• 한국물환경학회지
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• 제29권3호
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• pp.400-408
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• 2013

Total phosphorus was set as a target indicator to prevent eutrophication and algae growth, etc., in three major rivers (Nakdong River, Geum River and Yeongsang/Seomjin River) for the second phase (2011 ~ 2015) in total maximum daily loads (TMDLs) system. However, total phosphorus management was restrictively introduced, i.e., upstream of the Lake Daechung, in the Geum River watershed. Total phosphorus concentration and trophic levels in downstream of the Lake Daechung (include Mangyeong and Dongjin rivers) were increased more than upstream. Therefore, it is necessary to expand total phosphorus management in all watersheds of the Geum River. If total phosphorus was managed in all area of the Geum River watershed, it is possible to decrease total phosphorus concentration and trophic levels, and solve the unbalanced water quality between up and downstream of the Lake Daechung.

• Membrane and Water Treatment
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• 제14권1호
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• pp.27-33
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• 2023

In previous studies, solely ferric (Fe³⁺) and calcium (Ca²⁺) ions were commonly used for removal of PO₄-P (considered as T-P in this study) in wastewater via chemical precipitation. Herein, the removal of total phosphorus (T-P) in wastewater was performed using various mineral and lime dissolved solutions. The dissolution kinetics of different minerals (feldspar, olivine, elvan, illite, sericite, and zeolite) and lime was compared and used their solutions for T-P removal of real wastewater. The highest T-P removal (almost 90%) was obtained by the lime dissolved solution and followed by zeolite, illite, feldspar, and others. We observed a significant co-relationship (R of 0.96) between the amount of initial Ca²⁺ and T-P removal. This was induced by formation of hydroxyapatite-like mineral via Ca-P precipitation reaction at high pH solution. Furthermore, additional removal of suspended solid (SS) and chemical oxygen demand (COD) was achieved by only lime dissolved solution. Finally, the lime-feldspar dissolved solutions were prepared at different ratios (10-50%), which showed a successive T-P removal up to two times by samples of 40 and 50%.

• 한국물환경학회지
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• 제16권4호
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• pp.533-539
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• 2000

A bench-scale reactor using SBR process was experimented with an synthetic wastewater. The main purpose of this investigation was to evaluate applicability in the field and process removal efficiencies in terms of BOD and T-P and its corresponding kinetic parameters. Removal rate of phosphorus was 77% in terms of total phosphorus. Effluent concentrations were $9.8mg/{\ell}$ BOD and $1.1mg/{\ell}$ T-P. Effluent quality was maintained consistently stable by controlling decant volume and operating cycles. The efficiency for phosphorus removal was increased due to decrease in BOD-SS loading value in the range of $0.25{\leq}$aeration time ratio${\leq}0.52$.

• 한국물환경학회지
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• 제33권4호
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• pp.434-440
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• 2017

In order to understand the characteristics of phosphorus in the paddy field, this study analyzed $PO_4-P$ and T-P concentrations of irrigation water, flooding water, and runoff from 2008 to 2010. The variation of phosphorous form within hydrologic cycle around the rice paddy field was investigated using the ratio of $PO_4-P$ to TP. In addition, the correlation between pH, EC, and DO in flooding water was analyzed and the factors affecting phosphorus form in paddy field were investigated. The concentration of T-P in flooding water was high during the survey period, and the concentration of T-P in runoff was assumed to be decreased by dilution due to irrigation and rainfall. On the other hand, the ratio of $PO_4-P$ to T-P was lower in flooding water than those of irrigation water and runoff, which was interpreted to be due to the fact that the phosphorus fertilizer was applied in the paddy field but the adsorption was rapidly occurred to the paddy field by the soil. The similar proportions of $PO_4-P$ to T-P in flooding water and runoff suggest that the form of phosphorus outflowed from the paddy is influenced by the form of phosphorus in the flooding water of paddy field. In addition, DO concentration in flooding water showed negative correlation with the concentrations of $PO_4-P$ and T-P. The effort to survey frequent irrigation water quality data is required for the analysis of phosphorus behavior in the paddy water system since concentration of phosphorous and DO in irrigation water would influence rhe form of phosphorous in flooding water and subsequent runoff.

• 대한환경공학회지
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• 제34권5호
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• pp.295-303
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• 2012

본 연구는 DEPHANOX 공정내 분리조에 Al(III) ($Al_2(SO_4)_3{\cdot}17H_2O$)를 주입하여 유출수의 T-P 농도를 0.2 mg/L 이하로 유지하기 위한 주입량을 도출하고 Al(III) 첨가에 따른 질소 및 인 제거 효율을 평가하였다. 반응조 내에 Al(III)을 5, 10, 15 mg/L주입하여도 pH와 알칼리도 저감에 대한 영향은 나타나지 않았으며 반응조 내의 pH는 7~8 사이로 유지하였다. 응집제의 주입량이 증가할수록 유기물과 T-N 제거효율은 감소하였으나, T-P 제거효율은 주입량이 5, 10, 15 mg/L로 증가할수록 76.28, 84.02, 94.66% 증가하였다. Al(III)주입량 15 mg/L에서 유출수의 T-P 농도는 0.17 mg/L로 관찰되어 유출수의 T-P 농도를 0.2 mg/L 이하로 유지하기 위한 Al(III)의 주입량은 최소 15 mg/L 이상임을 확인하였다.