• Journal of Wetlands Research
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• v.18 no.3
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• pp.267-274
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• 2016

Sewerage supply in rural community is the important for water quality protection of water system such as river, lake and wetland. And characteristic of small scale wastewater system that have wide range of inflow and concentration in sewage should be considered for stable operation of small scale wastewater treatment plant. In this research, characteristics of flow ratio (flow / designed flow), effect on treatment efficiency of small scale wastewater treatment plant and assessment of optimal flow ratio were conducted through analysis on operation result of 18 small scale wastewater treatment plant in Bong-hwa gun. As a result, flow ratio shows the higher value during summer. However pollutants concentration in sewage was shown the higher concentration during autumn and winter. Treatment of small scale wastewater treatment plant is increased when flow ratio increased, and nutrient treatment efficiency is more sensitive to change of flow ratio than organic compound and suspended solids. According to this research result, it need to be maintained flow ratio 0.8 over value for stable treatment efficiency of small scale wastewater treatment plant.

• Journal of Wetlands Research
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• v.8 no.2
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• pp.45-51
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• 2006

Biological enhanced treatment and send filtration are established being operated to remove nutrients and MBAS(Methylene Blue Activate Substance) in the most of Waste Water Treatment Plant(WWTP) in Korea. However, untreated synthetic detergents and nutrients which directly run into the water system present an unpleasant view because of the foam, taste and odor generating filamentous periphytic algae and interrupting self-purification in the stream. Therefore, this research was enforced to know the MBAS removal efficiency of the sand filtration about G WWTP which reuses effluent as urban stream management water. As a result, the maximum removal efficiency using sand filtration was 63% after 24 hours and particularly 30% after 2 or 4 hours which turned out to be not that effective. In conclusion, It is recognized that other methods of MBAS removal and a research will be needed which reuse effluent as urban stream management water from now on. Because the MBAS removal with sand filtration is insufficient with economical efficiency from the fact that it needs long hours for a sand filtration treatment and the removal efficiency was almost below the expectation.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1501-1509
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• 2003

The simultaneous addition of xylanase (5,600 EXU/kg) and phytase (500 FTU/kg) feed enzymes to wheat-based broiler diets was investigated. Starter, grower and finisher diets, with three tiers of nutrient specifications, were fed to 1,440 broiler chicks kept on deep litter from 1-42 days post-hatch, without and with xylanase plus phytase, to determine the effects of diet type and enzyme supplementation on growth performance. The nutrient specifications of type A diets were standard; energy density and protein/amino acid levels were reduced on a least-cost basis to formulate type B diets and further reduced to type C diets. Phosphorus (P) and calcium (Ca) levels were adjusted in supplemented diets. From 1-42 days post-hatch, diet type significantly influenced growth performance. Birds on type C diets had lower growth rates (2,429 vs. 2,631 g/bird; p<0.001), higher feed intakes (4,753 vs. 4,534 g/bird; p<0.005) and less efficient feed conversion (1.96 vs. 1.72; p<0.001) than birds offered type A diets. Enzyme supplementation increased growth rates by 3.2% (2,580 vs. 2,501 g/bird; p<0.005) and improved feed efficiency by 2.7% (1.80 vs. 1.85; p<0.05) over the entire feeding period. There were no interactions between diet type and enzyme supplementation. At 21 days, 5 out of 30 birds per pen were transferred to cages to ascertain treatment effect on apparent metabolisable energy (AME) and nitrogen (N) retention. Xylanase plus phytase enhanced AME (13.48 to 13.91 MJ/kg DM; p<0.001) and N retention (56.3 to 59.7%; p<0.005). Carcass and breast weights of the caged birds were determined following commercial processing. Diet type significantly influenced breast weight, carcass weight and yield. Birds offered Type A diets, in comparison to Type C diets, supported heavier breast (467 vs. 424 g; p<0.001) and carcass weights (1,868 vs. 1,699 g; p<0.001) with superior carcass yields (71.8 vs. 70.6%; p<0.005). Enzyme addition increased carcass weight by 3.9% (1,752 vs. 1,821 g; p<0.005) and breast weight by 5.8% (431 vs. 456 g; p<0.01) without influencing yields. Feed ingredient costs per kg live weight gain and per kg carcass weight indicated that enzyme addition was economically feasible, where supplementation of Type A diets generated the most effective results. Importantly, soluble and total non-starch polysaccharide and phytate contents of the wheat used were typical by local standards. This study confirms the potential of supplementing wheat-based broiler diets with xylanase plus phytase but further investigations are required to define the most appropriate inclusion rates and dietary nutrient specifications in this context.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1309-1315
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• 2012

A total of 140 weaning pigs ((Landrace${\times}$Yorkshire)${\times}$Duroc, BW = $6.47{\pm}0.86$ kg) were used in a 5-wk growth trail to determine the effects of phytoncide supplementation on growth performance, nutrient apparent total tract digestibility (ATTD), blood profiles, diarrhea scores and fecal microflora shedding. Pigs were assigned randomly by BW into 5 treatments, dietary treatments were: i) NC, basal diet; ii) PC, NC+0.05% tylosin; iii) EO, NC+0.1% essential oil; iv) PP, NC+0.2% PP (phytoncide with 2% citric acid), and v) PA, NC+0.2% PA (phytoncide). Each treatment had 7 replicate pens with 4 pigs per pen. All pigs were housed in pens with a self-feeder and nipple drinker to allow ad libitum access to feed and water throughout the experimental period. During 0 to 2 wks, supplementation with essential oil and PA decreased (p<0.05) G/F compared with the other treatments. During 2 to 5 wks, supplementation with PA led to a higher (p<0.05) G/F than the other treatments. At 2 wk, ATTD of dry matter (DM) and gross energy (GE) in EO treatment were decreased (p<0.05) compared with NC treatment. Dietary PC treatment improved (p<0.05) ATTD of DM and E compared with the CON group, and PA and PP treatments showed a higher (p<0.05) ATTD of E than that in NC treatment. Pigs fed phytoncide (PA and PP) had a greater (p<0.05) ATTD of DM than those of NC and EO treatments at 5 wk. Moreover, supplementation with phytoncide elevated (p<0.05) the concentration of immunoglobulin (IgG) in blood at 2 wk. The inclusion of EO, PP and PA treatments showed a greater (p<0.05) amount of fecal Lactobacillus compared with CON group. However, no difference (p>0.05) was observed in diarrhea scores among treatments. In conclusion, phytoncide can elevate feed efficiency, nutrient digestibility, and improve the fecal Lactobacillus counts in weaning pigs. Our results indicated that the phytoncide could be used as a good antibiotics alternative in weaning pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.981-991
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• 2020

Objective: To evaluate calcium stearoyl-2 lactylate (CSL) performance as an exogenous emulsifier together with lipase for broiler diets. Methods: In total, 252 one-day-old Ross 308 broiler chickens were allocated in a completely randomized design to give 6 replications per treatment with 7 birds in each cage. There were six dietary treatments representing a 2×3 factorial arrangement consisted of two energy levels (standard energy [positive control, PC] and -100 kcal/kg of the requirement level [negative control, NC]) and three dietary treatments (without additives [CON], CON+CSL [CSL], and CON+CSL+lipase [CSL-Lipase]). Corn and soybean meal-based experimental diets containing vegetable oil were formulated. Growth performance, blood parameters, visceral organ weights, ileal morphology, nutrient digestibility, and cytokine gene expression were measured. Results: Birds fed a diet including CSL increased (p<0.05) lipase level in blood compared to birds fed a diet including CSL-Lipase on day 21. Similarly, higher (p<0.05) liver weight was observed in birds fed a diet including either CSL or CSL-Lipase on day 21. Birds fed NC diet with CSL improved (p<0.05) nutrient digestibility compared to the NC diet on day 21. However, birds fed a diet supplemented with CSL or CSL-Lipase did not affect (p>0.05) the weight gain, feed efficiency, ileal morphology, and cytokine concentrations during the experiment period, regardless of dietary energy levels. Conclusion: Our results indicated that CSL has a role in improving nutrient digestibility in young birds when supplemented to a corn-soybean meal based broiler diet.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.147-153
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• 2017

BACKGROUND: Soil water content strongly depends on weather condition and irrigation, and it could influence on crop nutrient use efficiency. This study was performed to assess nutrient uptake of soybean by soil water condition. METHODS AND RESULTS: In this study, nutrient leaching and crop uptake as affacted by water management practice was investigated using weighing lysimeter which is located in National institute of agricultural science, Wanju, Jeonbuk province from June 2015 to October 2016. Water supply for soybean (cv. Daewon) was managed with irrigation and rainfall. Nitrate leaching was greatest in the rainfall treatment at early July 2016. Yield of soybean in the rainfall treatment was only 25% compared to the irrigation due to the drought at flowering and podding period. The uptake of nitrogen was considerably reduced by drought whereas the uptake of phosphorus and potassium was less affected by drought. CONCLUSION: It was proven that nitrogen loss and uptake were dependent on soil water condition. Therefore, irrigation water management to maintain available soil moisture capacity is critical to nitrogen uptake and yield of soybean.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.373-386
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• 2017

The study was conducted to investigate seasonal nutrient dynamics in rice-cultivated soils collected from farmhouses of three large-scale environment-friendly agricultural districts (LEAD), Jangheung, Suncheon, and Okcheon in which environmental-friendly agriculture has been exemplarily practiced in Korea. Among three districts, Crop- livestock cycling organic farming system had been introduced only in Jangheung. pH and EC of farmhouse soils of three LEADs were ranged between 5.5 - 6.7 and $0.4-1.0dS\;m^{-1}$ from March to September, respectively. T-N was observed to be high on the farmhouse soil in Suncheon and K was observed to be lowest on farmhouse soil in Okcheon. Concentration of $NH_4-N$ in soil was observed to be highest on June, in particular on the farmhouse in Jangheung, but rapidly decreased due to the loss of fertilizer applied in Spring. Yield and harvest index were the highest on the farmhouse in Okcheon in which total annual gross production $ha^{-1}$ was nearly three time higher than those of other two farmhouses. Farmhouse soil of Okcheon was maintained the highest seasonal nutrient balance due to the high input of fertilizer. It was estimated that K balance in the farmhouse soil in Suncheon dropped to $-60kg\;ha^{-1}$ on September, and it might have some effect on the less rice productivity due to K deficiency. Farmhouse soil in Jangheung was maintained low seasonal balance of T-N and P but showed the highest N use efficiency in the rice grain. Based on above-mentioned results, we think Jangheung farmhouse can be recommended as a model farmhouse of LEADs.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.35-43
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• 2021

The application of nature-based solutions, such as low impact development (LID) techniques and green infrastructures, for stormwater management continue to increase in urban areas. Plants are usually utilized in LID facilities to improve their pollutant removal efficiency through phytoremediation. Plants can also reduce maintenance costs and frequency by means of reducing the accumulation of pollutants inside the facility. Plants have long been used in different LID facilities; however, proper plant-selection should be considered since different species tend to exhibit varying pollutant uptake capabilities. This study was conducted to investigate the pollutant uptake capabilities of plants by comparing the dry matter and nutrient contents of different plant species in roadsides, LID facilities, and landscape areas. The dry matter content of the seven herbaceous plants, shrubs, and arboreal trees ranged from 60% to 90%. In terms of nutrient content, the total nitrogen (TN) concentration in the tissues of herbaceous plants continued to increase until the summer season, but gradually decreased in the succeeding periods. TN concentrations in shrubs and trees were observed to be high from early spring up to the late summer seasons. All plant samples collected from the LID facility exhibited high TP content, indicating that the vegetative components of LID systems are efficient in removing phosphorus. Overall, the nutrient content of different plant species was found to be highly influenced by the urban environment which affected the stormwater runoff quality. The results of this study can be beneficial for establishing plant selection criteria for LID facilities.

• Animal Bioscience
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• v.37 no.7
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• pp.1246-1254
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• 2024

Objective: The goal of the current study was to investigate the impact of various concentrations of xylanase in energy-deficient corn-based diets on the growth performance, carcass characteristics, nutrient digestibility, and digesta viscosity in broilers from 7 to 35 days of age. Methods: A total of 280 seven-day-old Ross 308 broilers were randomly allocated to one of the five dietary treatments following a completely randomized design with 8 replicates and 7 birds per cage. The treatments were: i) positive control (PC, without xylanase); ii) NC-1 (80 kcal/kg ME reduced from PC); iii) NC-2 (100 kcal/kg ME reduced from PC); iv) NCX-1 (NC-1 + 2,000 U/kg xylanase); and v) NCX-2 (NC-2 + 3,000 U/kg xylanase). Body weight, weight gain, feed intake, and feed conversion ratio were determined weekly to evaluate growth performance. One bird per pen was sacrificed for ileal digesta collection to determine the viscosity and digestibility of energy, dry matter, crude protein on days 24 and 35, however breast and leg meat samples were obtained for proximate analysis (moisture, crude protein, fat, and ash) on day 35. Results: Birds fed diets supplemented with xylanase regardless of the amount had higher (p<0.05) body weights, daily gains, and improved feed efficiency compared to NC diets all throughout the experimental period. Feed intake was not affected (p>0.05) by the addition of xylanase. Moreover, lowered (p<0.05) viscosity of the ileal digesta were observed upon xylanase inclusion in the diets compared to the birds fed NC diets on day 24. Ileal nutrient digestibility and meat proximate composition were not affected (p>0.05) by xylanase. Conclusion: The present study indicated that the xylanase at 2,000 U/kg and 3,000 U/kg levels compensates for the 80 kcal/kg and 100 kcal/kg dietary energy levels, respectively, without having adverse effects on the growth performance, carcass characteristics, nutrient digestibility, and digesta viscosity of broilers.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.955-960
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• 2012

In most agricultural soils, ammonium ($NH_4{^+}$) from fertilizer is quickly converted to nitrate ($NO_3{^-}$) by the process of nitrification which is crucial to the efficiency of N fertilizers and their impact on the environment. The salinity significantly affects efficiency of N fertilizer in reclaimed tidal soil, and the soil pH may influence the conversion rate of ammonium to nitrate and ultimately affect nitrogen losses from the soil profile. Several results suggest that pH has important effects on recovery of fall-applied N in the spring if field conditions are favorable for leaching and denitrification except that effects of soil pH are not serious under unfavorable conditions for N loss by these mechanisms. Soil pH, therefore, deserves attention as an important factor in the newly reclaimed tidal soils with applying N. However, fate of N studies in a newly reclaimed tidal soils have been rarely studied, especially under the conditions of saline-sodic and high pH. Therefore, understanding the fate of nitrogen species transformed from urea treated into the reclaimed tidal soil is important for nutrient management and environmental quality. In this article, we reviewed yields of rice and fate of nitrogen with respect to the properties of reclaimed tidal soils.