• The Korea Swine Journal
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• v.21 no.12 s.244
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• pp.99-103
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• 1999

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.304-309
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• 1999

Biomass, tissue (foliage, stem. and root) nutrient concentration, and nutrient use efficiency (NUE) were determined for 1-year-old Pinus densiflora, Larix leptolepis and Betula platyphvlla var. japonica seedlings in a greenhouse under nitrogen (N) and phosphorus (P) fertilization treatments. There were no consistent patterns in the effect of fertilization on seedling growth, however, in most cases the addition of N and P had no stimulating effect on biomass. In general, seedling tissue N and P concentrations increased after fertilization. It appeared that fertilization induced luxury nutrient consumption because uptake was increased without altering biomass. The NUE. calculated as the ratio between total above and belowground production and nutrient content in seedlings, decreased with increasing N and P supply for P. densiflora and B. platyphylla var. japonica while that for L. leptolepisthe did not change. B. platyphylla var. japonica had the highest NUE, L. leptolepis the lowest, with P. densiflora having the intermediate NUE.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.6
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• pp.449-455
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• 2013

The effect of recycling ratio and fixed media on nitrate and phosphate removal was investigated in a pilot-scale wastewater treatment unit using synthetic wastewater. Addition of fixed media increased nitrate removal from 45 to 58% while no noticeable change was observed for Chemical Oxygen Demand (COD) and phosphate removal (<5%). Nitrate removal efficiency also enhanced (Ca 7%) when the influent wastewater flow was doubled (2Q), however phosphate removal was decreased from 40.9 to 26.6% with the increasing recycling rate. The attached biomass analysis showed the presence of bacteria (73.4 $mg/cm^2$) on the surface of added media in anoxic reactor. Pseudomonas aeruginosa a common denitrifying bacterium dominated the bacterial growth (58%) in the anoxic reactor which was determined using Fluorescence In Situ Hybridization (FISH) analysis.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.125-131
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• 2003

This study was carried out to develop INSUB(Indirected Aerated Submerged Biofilter) which can remove organics, nitrogen and phosphorus with an advanced treatment system. The results were as followed in laboratory model experiment. As for treatment of sewage, when economical efficiency was considered in practice, the highest removal efficiency was at 18hr of HRT, 1.017m/hr of superficial velocity and 40% of media packing ratio. Each removal efficiency for $COD_{cr}$, $COD_{Mn}$, $BOD_5$, T-N, and T-P was 90.6, 85.3, 95.0, 52.3 and 56.8%. To remove the nitrogen and phosphorus With high efficiency, first of all, denitrification have to be completed, then uptake of phosphorus have to completed. Therefor, mixture of anoxic and aerobic reactor was necessary for the high removal efficiency of nitrogen and phosphorus in INSUB.

• Korean Journal of Ecology and Environment
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• v.34 no.2 s.94
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• pp.106-118
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• 2001

The chemistry of porewater and exchangeable nutrients of sediment was determined to define potential influence of sediment nutrients on the water quality and the phytoplankton growth in Taechong Reservoir in March and May of 2000. The sediment-water interface showed almost anoxic state, < 0.5 mg $O_2/l$. Conductivity of the porewater was higher 1.9${\sim}$2.6 fold than that of sediment, and its variation was greater in the shallow water. Eh ranged from -12mV to -148 mV and bulk density from $1.17\;g/cm^3$ to $1.30\;g/cm^3$ and they did not differ among stations. The water content in the sediment ranged from 58% to 72% and organics from 8% to 13%, and they were higher toward the lower part of reservoir. Soil texture was in the order of sand>clay>silt and sandy sediment accounted for 97% of the total sediment. The total bacterial numbers and diatom abundance were high in the downstream of the reservoir. In porewater and exchangeable nutrients of sediment, nitrogen and phosphorus were mostly consist of the particulate form. Inorganic nitrogen was mostly composed of $NH_4$. Nitrogen of porewater was mostly an inorganic form while exchangeable nutrients were composed an organic form. However, phosphorus was composed of dissolved organic fraction in the porewater while inorganic fraction in the exchangeable nutrients. Silicon content of sediment was much exchangeable nutrients with 63%, and it was higher than in the porewater. In summary, the sediments of Taechong Reservoir were mostly composed of organics and assessed to be a eutrophic state.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.90-103
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• 2014

Distribution characteristics of water masses, dissolved inorganic and organic nutrients were investigated in the southern part of the East Sea of Korea in September, 2011. On the basis of the vertical profiles of temperature, salinity and dissolved oxygen, water masses in the study area were divided into 4 major groups, such as WM (water mass)-I, WM-II, WM-III, WM-IV. Their characteristics were similar to Tsushima Surface Water (TSW), Tsushima Middle Water (TMW), North Korea Cold Water (NKCW) and East Sea Proper Water (ESPW), respectively. In the vertical profiles of dissolved nutrients, dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) concentrations were highest in the WM-IV, followed by WM-III, WM-II, WM-I. On the contrary, distribution of dissolved organic nitrogen (DON) and dissolved organic phosphorus (DOP) were highest in the WM-I, followed by WM-II, WM-III, WM-IV. Although the DIN : DIP ratio in all of the water masses was similar to Redfield ratio(16), the DIN : DIP ratio in mixed layer was about 5.3, indicating that inorganic nitrogen is the limiting factor for the growth of phytoplankton. However, the DON proportion in dissolved total nitrogen (DTN) was about 70% in the mixed layer where inorganic nitrogen is limiting factor. Thus, enriched DON may play an important source of the nutrient for the growth of phytoplankon in the East Sea.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.35-40
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• 1999

$N(^{15}N)$ and $P(^{32}P)$ absorption by 2 year-old Cymbidium Jungfrau in solution culture were investigated. Growth, photosynthesis rate, chlorophyll content and mineral composition of Cymbidium in the solution culture with bark or granular rockwool were compared with these parameters in the conventional pot culture. Nitrogen absorption by Cymbidium was higher in full sunlight than in 60% of sunlight while P absorption was higher in 60% of sunlight. Sixty seven % of N absorbed in plant was redistributed to the bulb(39%) and leaves(28%) while 46% of P absorbed was fund in the bulb (36.2%) and leaves (10.2%). Accumulation of P in leaves was 3-fold lower than that of N. N and P absorption in 0.5 or 1 year- old daughter plant Bowing vigorously were greater than in immature daughter or mother plant. The absorption rate of phosphorus in Cymbidium was 350-fold lower than that of barley. Greater shoot length and bulb diameter, and higher fresh weight, photosynthesis rate and chloroployll content were observed in the solution culture than in the conventional pot culture. Solution culture had-also more content of N, P, K and Mg in leaves, bulb and root than conventional pot culture but did not that of Ca. A large part of the nutrient absorption was occurred during vegetative growth. Also, There was no difference between bark and rockwool in the solution culture due to the improvement of poor dispersion of nutrient solution in bark.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.291-297
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• 2012

This study was carried out to investigate the effect of dietary phytase on nitrogen and phosphorus excretion of gestating and lactating sows (Yorkshire ${\times}$ Landrace ${\times}$ Duroc). Twelve gestating sows and twelve lactating sows were used in this study and were divided into 2 groups (1 control group and 1 treatment group, 6 replications/group) the control group was without phytase and the treatment group was fed with phytase (750 FTU/kg) in the diet, respectively. Body weights of gestating and lactating sows were $208.9{\pm}13.8$ kg and $190.5{\pm}22.9$ kg, respectively. In gestating sows, feed intake was greater in phytase fed group than the control (P<0.05), but water intake and total excretion were not different between the groups. In lactating sows, feed and water intakes and total excretion were not different between the groups. The N intake of lactating sows was higher in phytase fed group than control (P<0.05) but N excretion ratio was not different. In lactating sows, N intake and excretion and N excretion ratio were not significantly different between the groups. P excretion and excretion ratio in gestating sows decreased by phytase treatment (P<0.05) as compared to control. In lactating sows, N intake and excretion was not significantly different by added phytase (P>0.05). Finally, dietary addition of phytase decreased P excretion in feces of gestating and lactating sows.

• Environmental engineer
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• v.18 s.190
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• pp.73-75
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• 2002

우리 환경인들의 삶의 터전인 현장에는 많은 유해$\cdot$위험요인들이 상존하고 있으나 이를 간과하거나 무시하고 지나쳐버림으로써 돌이킬 수 없는 중대재해가 빈번히 발생하고 있습니다. 이에 본지는 최근 발생된 환경오염방지시설 또는 생산공정 현장에서의 재해사례를 알려드림으로써 발생가능한 재해를 사전예방하고 회원 여러분들의 소중한 생명을 보호코자 합니다.

• Environmental engineer
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• v.19 s.206
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• pp.74-75
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• 2003

우리 환경인들의 삶의 터전인 현장에는 많은 유해$\cdot$위험요인들이 상존하고 있으나 이를 간과하거나 무시하고 지나쳐버림으로써 돌이킬 수 없는 중대재해가 빈번히 발생하고 있습니다. 이에 본지는 최근 발생된 환경오염방지시설관련 재해사례를 알려드림으로써 발생가능한 재해를 사전예방하고 회원 여러분들의 소중한 생명을 보호코자 합니다.