• 자원환경지질
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• 제47권1호
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• pp.71-85
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• 2014

오레곤 대륙 주변부 남부 하이드레이트 릿지에서 실시한 ODP Leg 204에서 회수한 코어 Site 1249C와 Site 1251B의 유기물 기원 및 유기지화학적 특성을 규명하기 위하여 원소분석과 Rock-Eval 열분석 및 동위원소 비 분석을 실시하였다. 분석결과 Site 1249C와 Site 1251B의 유기물은 해양기원 유기물이 우세하며 이러한 결과는 퇴적물의 퇴적당시 환경이 일반적인 해양 환경이었음을 시사한다. 그러나 Rock-Eval 열분석 결과는 다른 분석결과와 반대의 결과를 나타내는데 이러한 결과는 열적으로 미성숙한 유기물이 열분석 과정에서 유기물의 특성이 제대로 반영되지 못하기 때문이다. 따라서 열분석 결과 해석은 다양한 지화학적 결과를 종합하여 해석할 필요가 있다. 코어의 유기물 기원이 동일함에도 불구하고 Site 1249C는 전 구간에서 가스 하이드레이트의 집적이 높은 반면, Site 1251B는 가스 하이드레이트가 일부 구간에서만 소량 발견되었다. 이러한 결과는 하이드레이트 정상부에 위치한 Site 1249C는 가스 하이드레이트 생성에 필요한 심부 열기원 가스가 천부 퇴적물로 이동할 수 있는 이동 통로(Horizon A, BSR2)가 존재하는 것을 시사한다. 그러나 가스 하이드레이트 집적이 미비한 분지 지역의 Site 1251B는 열기원 가스가 심부로부터 이동할 수 있는 가스 이동 통로가 제한적이고 그에 따른 가스 공급이 원활하게 이루어지지 않기 때문에 현장 퇴적물의 속성작용에 의한 생물기원 가스가 우세하여 가스 하이드레이트 생성이 제한적인 것으로 추정된다.

• 한국해양학회지:바다
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• 제14권2호
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• pp.80-89
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• 2009

동해의 독도 사면 지역에서 퇴적물 선상 배양과 $^{15}N$ isotope pairing technique를 이용하여 측정한 퇴적물 산소요구량과 탈질소화율은 각각 $1.04{\sim}9.08\;mmol\;m^{-2}\;d^{-1}$와 $7.06{\sim}37.67\;{\mu}mol\;m^{-2}\;d^{-1}$로 유사한 수심의 다른 심해 지역에 비해 모두 높게 측정되었다. 퇴적물 산소요구량과 탈질소화율은 퇴적물 내 유기 탄소 함량이 높은 정점에서 높았으며, 표층 퇴적물 내 유기물 함량은 질산화에 의해 생성된 질산염을 이용하는 탈질소화(coupled nitrification-denitrification)와 높은 상관관계를 보였다. 이는 본 조사 지역의 퇴적물 산소요구량뿐만 아니라 탈질소화율 역시 표층 퇴적물 내 유기물에 가장 큰 영향을 받는 것을 시사한다. 독도 사면 지역의 표층 퇴적물 내 유기 탄소 함량은 $1.8{\sim}2.4%$로 다른 심해 지역보다 높게 측정되었으며, 이는 높은 일차생산량에 의해 내보내기 생산이 높기 때문으로 추정된다. 독도 사면 지역에서 표층 퇴적물 내 유기물 농도는 일차생산에 의한 내보내기 생산에 의해 조절되며, 내보내기 생산이 퇴적물에서 일어나는 퇴적물 산소요구량과 탈질소화율 같은 유기물 분해율의 가장 큰 조절 요인인 것으로 추정된다.

• Environmental Engineering Research
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• 제25권1호
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• pp.80-87
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• 2020

Landfill waste decomposition generates a dark effluent named, leachate which is characterized by high organic matter content. To minimize these polluting effects, it becomes necessary to develop an effective landfill leachate treatment process. The objective of this study was to evaluate the performance of an innovative approach based on air stripping, anaerobic digestion (AD) and aerobic activated sludge treatment. A reduction of 80% of ammonia and an increase of carbon to nitrogen ratio to 25 were obtained, which is a suitable ratio for AD. This latter AD was performed in fixed bed reactor with progressive loading rate that reached 2 and 3.2 g COD/L/d for the raw and diluted leachate (1:2), respectively. The anaerobic treatment led to significant removal of chemical oxygen demand (COD) and biogas production, especially for the diluted leachate. The COD removal was of 78% for the raw leachate and a biogas production of 4 L/d with 70% methane content. The use of the diluted leachate led to 81% of COD removal and 7 L/d biogas with 75% methane content. It allowed a removal of 77% COD and more than 97% of the organic compounds present in the initial leachate sample.

• 한국유기농업학회지
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• 제27권4호
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• pp.529-540
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• 2019

The present study investigated the effect of forage sources and their inclusion levels in diet on the rumen fermentation of Korea traditional goat. Timothy and alfalfa were used as forage sources. Forages were mixed with concentrate diet in different ratios. The ratios of forage to concentrate diets were varied to 1:9, 5:5 and 9:1. The rumen fluid of goat was gathered from slaughter house. Dry matter digestibility was decreased and methane production was increased as forage levels in diet was increased. When forage sources, timothy and alfalfa, were compared, groups with timothy showed greater methane production than the groups of alfalfa. Molar ratio of produced acetate and valerate were increased when forage level in diet was increased. In the case of propionate and butyrate, they were decreased as elevated forage levels in diet. The result of this study provided a basic information for rumen fermentation of Korean traditional goat and these information could be applied in the development of nutritional and feeding strategy.

• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.785-790
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• 2001

Twelve indigenous male goats, comprising of six intact and six castrated (2.5-3 years; $24.4{\pm}0.62kg$) were assigned evenly into two dietary treatments, viz. $I_0$ and $I_{100}$ and were used to study the effect of supplementation of iodine on the nutrient utilization when their diet contained Leucaena leaf meal. They were offered a conventional concentrate mixture along with Leucaena leucocephala leaf meal, the latter to meet 50% of their crude protein (CP) requirements, and supplemented with either no iodine ($I_0$) or 0.1 mg of iodine ($I_{100}$)/day/animal as potassium iodide for a period of 105 days. Wheat straw given ad libitum was the sole source of roughage. A metabolism trial of 8 days duration was conducted after 90 days of experimental feeding. It was observed that the overall dry matter (DM) intake during experimental period was higher (p<0.05) in $I_{100}$ group as compared to $I_0$ group (508.6 vs. $443.7g\;d^{-1}$). The intake of CP, digestible crude protein (DCP) and metabolisable energy (ME), although non-significant, tended to be higher in the iodine supplemented group, $I_{100}$. Digestibility of dry matter, organic matter (OM), CP, ether extract and crude fiber (CF) did not differ (p>0.05) between the treatments. However, nitrogen retention was higher (p<0.01) in $I_{100}$ than $I_0$ with the values being 2.63 and $1.70g\;d^{-1}$, respectively. No difference (p>0.05) was evident in the retention of calcium and phosphorus between the two groups. The castrated animal exhibited lower DM intake concurrent with higher digestibility of DM and crude fibre (p<0.05), and organic matter and total carbohydrates (p<0.01) when compared to intact ones. It was concluded that supplementation of iodine to leucaena based ration may help in improving the DM intake and nitrogen utilization by goats.

• Fisheries and Aquatic Sciences
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• 제21권11호
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• pp.32.1-32.7
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• 2018

Trout production is a growing activity in recent years but requires new alternative sources of feed to be sustainable over time. The objective of this research was to determine the apparent digestibility coefficient (ADC) of dry matter (DM), organic matter (OM), crude protein (CP) and digestible energy (DE) of $ka{\tilde{n}}iwa$ (Chenopodium pallidicaule Aellen), kiwicha (Amaranthus caudatus L), quinoa (Chenopodium quinoa Willd), beans (Phaseolus vulgaris L.), sacha inchi, (Plukenetia volubilis L) and jumbo squid (Dosidicus gigas) meal in juvenile rainbow trout. The experimental diets were composed of a 70% basal diet and 30% of any raw materials. The ADC was determined by the indirect method using insoluble ash as a non-digestible marker. Jumbo squid, sacha inchi and quinoa showed the highest values of ADC (%) of DM (84.5, 73.5 and 69.7), OM (89.1, 78.4 and 72.9), CP (93.2, 98.0 and 90.3), and DE (4.57, 4.15 and 2.95 Mcal/kg DM), respectively. The ADC values for $ka{\tilde{n}}iwa$, kiwicha and bean were significantly lower. In conclusion, quinoa meal and jumbo squid meal have an acceptable digestibility but sacha inchi meal is a potential alternative for rainbow trout feeding in the future.

• 한국초지조사료학회지
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• 제11권2호
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• pp.108-115
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• 1991

A field experiment was conducted to evaluate the effects of cattle compost application on the change of soil physical properties and their relationship to yield performance of selected main forage crops. Maize(CV. Suweon 19) and sorghum hybrids(CV. Pioneer 9'31) as a summer crops and winter rye were grown on newly reclaimed red yellow soils(Fine loamy, Typic Hapludults) under different application rate of cattle compost associated with chemical NPK fertilization, from Oct. 1986 to Sept. 1989. Experimental field was laid down as a split plots design with four replications. The results obtained are summarized as follows: 1. Cattle compost application reclaimed soil physical propeties, such as formation of granular structure and water holding capacity, and it result in a great increase of plant growth and the rate of dry matter accumulation. 2. While cattle compost treatment reduced the portion of soild phase of the three phase constituents of soils, it increased the portion of air phase and liquid phase comparatively. 3. Organic matter, N, P, K, and mineral content in soil were markedly increased in the plot treated with compost. 4. Cattle compost application increased fodder production both in maize-rye and sorghum hybrids-rye cultivation. Annual dry matter yield of maize-rye cropping was 2183(NI'K only), 2425(NPK+compvst 3000 kg) and 2800kg/lOa(NPK + compost 6000kg/10a).

• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.474-478
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• 2001

Eighteen Murrah male buffalo calves were allotted into three groups of six each. The calves in group I (control) were fed with whole milk, skim milk, calf starter and green maize fodder. The calves in group II (high butyric acid) and group III (low butyric acid) were fed with the same diet as control along with 24 ml and 12 ml of butyric acid/calf/day for 120 days, respectively for 120 days. Dry matter intake was higher in group II and III as compared with group I. Digestibility of dry matter, organic matter, crude protein, crude fibre, ether extract, neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose was the highest in group II followed by group III and the control group. Body weight gain and conversion efficiency of dry matter, digestible crude protein and total digestible nutrients were better in group II. Cost of feed for per unit of live weight gain was the lowest in group II. It was concluded that dietary addition of butyric acid (24 ml/day) was economical and had positive effect on the performance of Murrah buffalo calves.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.680-684
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• 1998

The effect of feeding heifers young Napier grass (7-weeks regrowth) or old Napier (16-weeks regrowth) supplemented with either wilted Desmodium intortum, Sesbania sesban or dried Calliandra calothyrsus leaves on intake and live weight changes was evaluated in a 67-day trial. Thirty-two Friesian heifers with an average live weight of 271 kg and 16.8 months old were randomly allocated to the four diets. The diets were either ad libitum young Napier grass or old Napier grass supplemented with 25% of either Sesbania, Desmodium or Calliandra. There was significant difference in chemical composition between the young and old Napier grass. Significant differences (p < 0.05) were observed on intake of dry matter, organic matter, crude protein and neutral detergent fibre. The total dry matter intake was 2.77, 2.86, 2.62 kg/100 kg live weight (LW) for Desmodium, Calliandra and Sesbania supplemented diets, respectively. A dry matter intake of 3.11 kg/100 kg LW was observed on the heifers fed young Napier grass. The mean daily gains were 638, 732, 606, and 1,001 g/day for Desmodium, Calliandra, Sesbania supplemented and young Napier grass diets respectively. Low level supplementation rate (1-1.5 kg DM/day) was adequate to maintain good growth rate when the heifers were fed old Napier grass.

• Asian-Australasian Journal of Animal Sciences
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• 제29권7호
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• pp.965-970
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• 2016

This study was conducted to determine the effects of freezing and supplementation of molasses (M), lactic acid bacteria (LAB) and LAB+enzyme mixture on chemical and nutritional composition of sunflower silage (SF). Sunflower crops were harvested (at about $29.2%{\pm}1.2%$ dry matter) and half of fresh sunflower was ensiled alone and half was frozen (F) at $-20^{\circ}C$ for 7 days. Silage additives were admixed into frozen SF material. All samples were ensiled in glass jars with six replicates for 90 days. The treatments were as follows: i) positive control (non-frozen and no additives, NF), ii) negative control (frozen, no additives, F), iii) F+5% molasses (FM), iv) F+LAB (1.5 g/tons, Lactobacillus plantarum and Enterococcus faecium, FLAB); v) F+LAB+enzyme (2 g/tons Lactobacillus plantarum and Enterococcus faecium and cellulase and amylase enzymes, FLEN). Freezing silage increased dry matter, crude ash, neutral detergent fiber, and acid detergent lignin. The organic matter, total digestible nutrient, non-fiber carbohydrate, metabolizable energy and in vitro dry matter digestibility were negatively influenced by freezing treatments (p<0.05). In conclusion, freezing sunflower plants prior to ensiling may negatively affect silage quality, while molasses supplementation improved some quality traits of frozen silage. Lactic acid bacteria and LAB+enzyme inoculations did not effectively compensate the negative impacts of freezing on sunflower silage.