• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.499-503
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• 2008

In order to control the non-point source pollution, a vegetative filter strips (VFS) was set up and the site-monitoring was performed. The objective of this study is to investigate the influence of the plant coverage on treatment efficiency of total nitrogen (T-N) and total phosphorus (T-P) using vegetative filter strips. According to the results, it seemed that the treatment efficiencies of T-N and T-P were closely related with the plant coverage ratio. The results showed that treatment efficiency of T-P average 50% at higher than 50% of the plant coverage and 20~23% at lower than 50% of the plant coverage. Also, the treatment efficiency of T-N increased with the increase of the plant coverage ratio.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.759-764
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• 1999

In intensive agriculture, exceeded chemical fertilizer application would increase the concentration of nitrate nitrogen in groundwater. Consequently, it could bring the eutrophication in lakes and streams. The present study examined runoff loading of nitrogen and phosphorus from the paddy field during non-cropping season. The runoff loading of total-N, ammonia-N, nitrate-N and total-P were 12.96kg/ha, 5.42kg/ha, 1.52kg/ha and 1.41kg/ha. When the runoff loading of nutrients was compared by runoff water and sediments. About 70-80% of total-N by runoff water and the rest 20-30% by runoff sediments were flowed into streams. But 60-70% of total-P by runoff sediments and the rest 30-40% by runoff water were flowed into streams. The phosphorus compounds, which were flowed into streams by runoff sediments and then sedimented, keep exchanging with water at water body in undelivered condition. And it moves gradually into water layer. This process can cause eutrophication continually and repeatedly in water environment. So, a sound program is needed to reduce soil erosion from farmlands.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.2
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• pp.63-70
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• 2000

The present study was carried out for 7-months (from October 1.1997 to April 30. 1998) at a rice cultivation area blocked from livestock farming, farmstead and industrial complex to investigate the runoff loading of nitrogen and phosphorus in a plot(5,000$m^2$) paddy field areas. The runoff loading of total-N, amminia-N nitrate-N and total-P were 12.96kg/ha, 5.42kg/ha, 1.52kg/ha and 1.41kg/ha , respectively. When the runoff loading of nutrients was compared by dissolved and adsorbed forms, about 66% of total-N by dissolved form and the rest 34% by adsorbed form were flowed into streams. But 56% of total-P by adsorbed form and the rest 44% by dissolved form were flowed into streams. The phosphrous compounds , which were flowed into streams by runoff sediments and then sedimented, keep exchanging with water at water body in undelivered condition. And it moves gradually into water layer. This process can cause eutrophication continually and repeatedly in water environment . So, a sound program is needed to reduce soil erosion from farmlands.

• Journal of Food Hygiene and Safety
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• v.9 no.4
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• pp.229-235
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• 1994

It is very important to investigate the sanitary chemical conditions of farmwaters used for cattle breeding in the dairy farms. For this purpose we examined pH, KMnO4 consumption, total hardness, chloride, sulfate, NH3-N, NO3-N, fluoride, lead, iron, manganese, cadmium, copper, zinc and chrome in the farmwaters sampled 2 times(spring and summer)in Choongcheongnam and Kangwon Province. The pH of farmwaters in Choongcheongnam and Kangwon Province was 6.49$\pm$0.09, 6.70$\pm$0.06, total hardness 90.21$\pm$7.07, 64.53$\pm$6.38 mg/ι, consumption of KMnO4 4.13$\pm$0.62, 4.34$\pm$0.26mg/ι, NO3-N 6.51$\pm$0.55, 3.61$\pm$0.58 mg/ι, chloride ion 20.51$\pm$1.99, 5.41$\pm$1.36 mg/ι and sulfate ion 6.61$\pm$1.02, 7.28$\pm$1.30 mg/ι, respectively. But NH3-N was scarcely detected. Fluoride, iron, lead, cadmium, zinc, manganese and chrome were not detected from the tested farmwaters. There was high significance between each other in total hardness, NO3-N, chloride ion and sulfate ion. There was regional and seasonal significance in only NO3-N but only regional significance in total hardness and chloride ion.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.2
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• pp.9-17
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• 1986

Effect of nitrogen rate with and without chance of Phosphorus and Potassium rate was investigated in a field experiment. Percentage of plant mortality after transplanting increased with N rates above 32.5kg/10a. The content of total nitrogen increased and postassium decreased slightly as the rates of applied N was increased, but the contents of total alkaloid and phosphorus were not affected at each growing stage. It was considered that the application of 17.5kg of P2O5 and 35.0kg of K2O Per 10a might be sufficient for high yield and good Quality. As the N rates being increased, the yield, value, contents of total alkaloid and total nitrogen of cured leaf increased However, the Brice per kg was not significantly different among 17.5 ~ 37.5kg / 10a of N rates. The application of 37.5kg/10a of N may be profitable for farm economy; but, the N application should be controlled 17.5~22.5kg/10a for the low nitrogen and alkaloid leaf.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.1
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• pp.49-55
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• 1985

low grade leaves of flue-cured (N.C. 2326) and air-cured (Br 21) have been heated at $140^{\circ}C$ for 10 and 20 minutes, respectively. As heating duration increased, each contents of nicotine, total nitrogen, total sugar and free amino acid decreased in both leaves. The result obtained from this experiment are as following 1. Nicotine content decreased in both leaves. Heating for 10 and 20 minutes showed respectively nicotine decrease of 13.2% and 21.6% for Br 21 and 8.2% and 13.2% for N.C.2326. Decrease of total nitrogen and total sugar was inversely proportional to the heating duration. N.C. 2326 in the decrease out numbered Br.21 by the ratio 2: 1 for 10min.-heating, and 5:4 for 20 min.-heating. 3. Total free amino acid was decrease by 17.1% and 13.85 for N.C. 2326 and Br 21, respectively when heated for 10 min., and 25.6% and 26.5% respectively when heated for 20 min. When sucrose was added to Br 21, th decrease ratio of total free amino acid of Br.21 was increased. It is suggested that the addition of sucrose could promote the browning reaction in Br 21 leaves.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.7
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• pp.49-56
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• 2003

Nonpoint source pollutant loading from watershed may cause a problem to the water quality of the reservoir and stream. The characteristics of stream flow and water quality were monitored to investigate the runoff loading of the Namdae-cheon watershed from May in 1999 to October in 2003. Stage-discharge rating curve at the stream gauging site was established, and annual stream runoff of the study watershed was estimated as 499.4∼1,330.8mm during four years. The concentrations of total-nitrogen and total-phosphorus of stream water quality ranged from 0.76 to 6.95mg/L and from 0.0010 to 0.2276 mg/L, respectively, where T-N was generally higher than the water quality standard 1.0 mg/L for agricultural water use. The loads by unit generation of pollutant mass with respect to population, livestock, land use in this watershed were calculated. The runoff pollutant loadings by concentrations of total-N and total-P were estimated during study period, where the annual runoff loading of total-P was much less than the load by pollutant mass unit generation. The relations between stream discharge and water quality were analysed, and there was a high correlation for total-N but low for total-P. These results will be used to develop the monitoring techniques and water quality management system of agricultural watershed.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.580-585
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• 2005

Natural environment of Weolgok-ri watershed has been well preserved as a traditional agricultural watershed. A year record of streamflow, $NO_3-N$, T-N and T-P concentrations data(Apr, 2004-Mar. 2005) was examined to estimate annual and seasonal patterns of pollutnat loads in streamflow and baseflow from the agriculture watershed. To estimate pollutant loads from baseflow, baseflow component from total stream flow was seperated using digital filter method in the Web-based Hydrograph Analysis Tool system. Loads of $NO_3-N$, T-N and T-P from streamflow and baseflow were evaluated to investigate pollutant loads contribution by baseflow. The $NO_3-N$, T-N, and T-P loads from streamflow were 13.85 kg/ha, 45.92 kg/ha and 1.887 kg/ha, respectively. $NO_3-N$, T-N and T-P loads from baseflow were 7.43 kg/ha, 24.70 kg/ha, 0.582 kg/ha, respectively. It was found that $NO_3-N$ and T-N loads were contributed by the baseflow(53% and 53% of Total-loads) than the direct runoff(47% and 47% of Total loads). However, only 30% of total T-P was contributed by the baseflow. It is recommended that one needs to assess pollutant load contribution by the baseflow to identify appropriate control strategies for effective watershed management.

• Journal of the Korean institute of surface engineering
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• v.27 no.3
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• pp.143-148
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• 1994

Effects of process variables of HCD ion plating on the film composition of Ti(C, N) were analyzed. The mole ratio of carbon to nitrogen and that of non-metal to titanium in the film primarily depend on the partial pressure ratio of ($C-2H_2$/ $N_2$) and total reactive gas pressure, respectively. The amount of nonmetallic com-ponents increases in nonlinear fashion as the total gas pressure due to the different reactivity of $C-2H_2$ and $N_2$ gases with Ti. The nonmetallic components was saturated dwith nitrogen when the nitrogen gas was more than 60% of total reactive gas. These two process variables could be related systematically using the concept of effective pressure in which the difference of reactivity of each gas was normalized.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.617-626
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• 2003

This experiment employed a rumen simulated continuous culture system to examine the possibility of improving the rumen bypass of polyunsaturated fatty acids (PUFA) by using a high proportion of concentrate in the feed, and compared soya and linseed in terms of conjugated linoleic acid (CLA) production. No effect of type of fat source was observed on ruminal fermentation. A high proportion of concentrate (80%) in the feed decreased (P<0.001) vessel pH but increased (P<0.01) ammonia nitrogen, total VFA, acetate, butyrate and valerate concentrations compared with a low proportion (40%). Fat sources (soya vs. linseed) and concentrate ratio in the feed did not affect digestibilities of organic matter (OM), total nitrogen, neutral detergent fiber (NDF) and acid detergent fiber (ADF). Soya increased the flows of trans C18:1, C18:2 n-6 and C18:3 n-3 compared with linseed. The difference in fat source alone did not affect the flow of CLA but this was increased when high levels of soya and linseed were associated with a high proportion of concentrate in the feed. There was no effect of fat source on biohydrogenation of C18:1 n-9 and C18:2 n-6, but biohydrogenation of C18:3 n-3 and total C18 PUFA was higher with the linseed than with the soya treatment. A high proportion of concentrate decreased biohydrogenation of C18:2 n-6, C18:3 n-3 and total C18 PUFA compared with a low proportion.