• 한국제4기학회지
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• 제17권2호
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• pp.163-163
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• 2003

The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest zone. At the old-growth deciduous forest near Soribong-peak (533.1m) in KEF, we have established a permanent plot and a flux tower, and the site was registered as a KLTER site and also a KoFlux site. In this study, we aimed to present basic ecological characteristics and synthetic data of carbon budgets and flows, and some monitoring data which are essential for providing important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function. We made a stemmap of trees in 1 ha plot and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area 28.0 m2/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66cm. Soil texture is loam or sandy loam, and its pH was from 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the l.2m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. Litterfall was collected in circular littertraps (collecting area： 0.25m2) and mass loss rates and nutrient release patterns in decomposing litter were estimated using the litterbag technique employing 30cm30cm nylon bags with l.5mm mesh size. Total annual litterfall was 5,627 kg/ha/year and leaf litter accounted for 61% of the litterfall. The leaf litter quantity was highest in Quercus serrata, followed by Carpinus laxiflora and C. cordata, etc. Mass loss from decomposing leaf litter was more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% of C. laxiflora and 84% of C. cordata litter disappeared, while about 48% in Q. serrata litter lost over two years. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. And then we have drawn a schematic diagram of carbon budgets and flows in each compartment of the KEF site.

• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1599-1605
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• 2002

In this study, three different experiments were conducted to evaluate the nutritional value of apple pomace produced in southern areas of the Republic of Korea (South Korea). The effects of combining apple pomace in different ratios with commercial concentrates and rice straw in the diets of Korean native goats (Capra hircus) were examined. In experiment I, in situ DM and CP disappearances from nylon bags incubated in the rumen of goats showed that greater amounts of DM and CP were released from apple pomace than those from concentrates at the later stages of incubation, but only after 48 h for DM and CP, respectively. This was reflected in the higher 'b' value of the slowly degradable fraction of the apple pomace compared to the concentrates. Prior to these times the trend was reversed. In experiment II, Korean native goats were fed a diet containing apple pomace with either rice straw or rice straw and concentrates, and the in vivo nutrient digestibilities compared to animals receiving an alfalfa hay. DM digestibility in the animals given apple pomace plus concentrates with rice straw (66.86%) were similar to the goats given alfalfa hay only (69.09%) but significantly greater than for a diet of rice straw plus concentrates. In experiment III, an in vivo study was conducted to investigate the inclusion of 30 to 60% apple pomace pre-mixed with rice straw, rice bran and concentrates on the nutritional value for Korean native goats. Apple pomace mixed diets had higher DM intakes, nutrient digestibility and nitrogen retention than diets without apple pomace, which may have been due to the higher non-structural carbohydrates (NSC) and less ADF and NDF than those in other treatments. Replacement of concentrates with apple pomace in rice straw based diets of Korean native goats fed either separately (experiment II) or by pre-mixing (experiment III) gave satisfactory feed intake, digestibility, pH of ruminal fluid and production of $NH_3$-N and VFA in the rumen of goats. The results of this study infer that apple pomace can be included at levels of up to 60% in the diets of goats without dramatic effect on the animal.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1054-1062
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• 1999

The effects of dry roasting whole faba beans (WFB) and whole lupin seeds (WLS) at 110, 130 or $150{^{\circ}C}$ for 15, 30 or 45 min on rumen (RDCP%), estimated intestinal (IDCP%) and total tract disappearance of CP (TDCP%) and intestinal availability (IARUCP%) of rumen undegraded CP (RUCP%) were determined. The RDCP values were estimated by in sacco technique by incubating nylon bags for 8, 12 and 24 h in the rumen of dairy cows. The IDCP and IARUCP values were estimated using a sequence of ruminal incubation, in vitro incubation in acid-pepsin for 1 h and then in pancreatin for 24 h of three-step in vitro procedure technique. Dry roasting at 130 and $150^{\circ}C$ decreased RDCP with correspondingly increasing IDCP. The IDCP value generally increased from 12.3(raw) to 8.6, 14.8 and 39.6% (WFB) and from 28.3 (raw) to 33.7, 36.2 and 56.2% (WLS) at 8 h rumen incubation; from 2.9 (raw) to 2.9, 4.6 and 23.3% (WFB) and from 19.6 (raw) to 19.0, 24.0 and 46.6% (WLS) at 12 h rumen incubation; from 1.3 (raw) to 1.9, 1.7 and 11.0% (WFB) and from 4.4 (raw) to 4.2, 10.7 and 36.7% (WLS) at 12 h rumen incubation as the temperatures rose to 110, 130 and $150{^{\circ}C}$ respectively. The TDCP values were always high and increased by time in the rumen, the average values of which were 97.9, 96.6; 99.2, 96.9 and 99.6, 98.7% for WFB and WLS, respectively, at 8, 12 and 24 h rumen incubation. But within the same retention time, TDCP was generally unchanged. The average IARUCP increased from 87.3 (raw) to 87.4, 88.7 and 92.0% (WFB); from 87.6 (raw) to 88.9, 91.5 and 93.0% (WLS) at roasting temperatures of 110, 130 and $150{^{\circ}C}$, respectively. It was concluded that dry roasting can shift the digestion of CP from rumen to the lower gastrointestinal tract without depressing the digestion of RUCP. The best processing condition in this study was dry roasting at $150{^{\circ}C}$ for 45 min in terms of effects on the disappearances and availability of CP. Research data on intestinal availability of individual amino acids need to be further investigated.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.673-679
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• 1998

The experiment was conducted to determine in situ rumen degradability of soybean meal (SM), fish meal (FM), sesame cake (SC) and Italian ryegrass hay (IRGH) and the effect of supplementing the above protein meals to IRGH on digestibility and balance of nutrients in three Saanen goats. For measuring the degradability, nylon bags containing each meal were incubated in the rumen of one fistulated dry cow for 3, 6, 12, 24, 36, and 48 hrs. Degradability revealed that SM protein was highly degradable in the rumen (99.1%), while FM protein was less degradable (76.8%) with SC protein being intermediate (91.2%) at 48 hrs of incubation (p < 0.01). Degradation rate of the potentially degradable fraction was estimated to be 12.12, 5.88 and 5.88%/hr for SM, FM and SC, respectively. In the metabolism trial, all goats were offered daily 900 g IRGH and one of the supplements, SM (100 g), FM (75 g) or SC (100 g). Intake of DM, OM, CP and GE was similar among diets. However, digestibility of OM for SC diet was significantly lower than that for diets supplemented with FM and SM (p < 0.10). Nitrogen (N) excreted in faeces (p < 0.05) and in urine (p < 0.10) was, respectively, higher and lower for SC diet than that for the other two diets. The same tendency was observed in energy losses in faeces (p < 0.10) and in urine (p < 0.05). There was no difference in energy loss in methane or in heat production among diets. Consequently, no significant difference was observed in N retention (2.13, 0.42 and -0.11 g/day for FM, SC and SM diet, respectively) or in energy retention (-1.49, -2.14 and -2.70 MJ/day for FM, SM and SC diet, respectively). These results showed that protein supplements affected the digestion of diets based on grass hay with 7.45% CP in DM in goats, although there was no significant influence on N or energy retention.

• Asian-Australasian Journal of Animal Sciences
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• 제22권4호
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• pp.534-541
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• 2009

The aim of this study was to evaluate the effects of gamma irradiation (${\gamma}$-irradiation) at doses of 15, 30 and 45 kGy on chemical composition, anti-nutritional factors, ruminal dry matter (DM) and crude protein (CP) degradibility, in vitro CP digestibility and to monitor the fate of true proteins of full-fat soybean (SB) in the rumen. Nylon bags of untreated or ${\gamma}$-irradiated SB were suspended in the rumens of three ruminally-fistulated bulls for up to 48 h and resulting data were fitted to a nonlinear degradation model to calculate degradation parameters of DM and CP. Proteins of untreated and treated SB bag residues were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Digestibility of rumen undegraded CP was estimated using the three-step in vitro procedure. The chemical composition of raw and irradiated soybeans was similar. Results showed that phytic acid in ${\gamma}$-irradiated SB at dose of 30 kGy was eliminated completely. The trypsin inhibitor activity of 15, 30 and 45 kGy ${\gamma}$-irradiated SB was decreased (p<0.01) by 18.4, 55.5 and 63.5%, respectively. From in sacco results, ${\gamma}$-irradiation decreased (p<0.05) the washout fractions of DM and CP at doses of 30 and 45 kGy, but increased (p<0.05) the potentially degradable fractions. Gamma irradiation at doses of 15, 30 and 45 kGy decreased (p<0.05) effective degradability of CP at a rumen outflow rate of 0.05 $h^{-1}$ by 4.4, 14.4 and 26.5%, respectively. On the contrary, digestibility of ruminally undegraded CP of irradiated SB at doses of 30 and 45 kGy was improved (p<0.05) by 12 and 28%, respectively. Electrophoretic analysis of untreated soybean proteins incubated in the rumen revealed that ${\beta}$-conglycinin subunits had disappeared at 2 h of incubation time, whereas the subunits of glycinin were more resistant to degradation until 16 h of incubation. From the SDS-PAGE patterns, acidic subunits of 15, 30 and 45 kGy ${\gamma}$-irradiated SB disappeared after 8, 8 and 16 h of incubation, respectively, while the basic subunits of glycinin were not degraded completely until 24, 48 and 48 h of incubation, respectively. It was concluded that ${\gamma}$-irradiated soybean proteins at doses higher than 15 kGy could be effectively protected from ruminal degradation.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.376-380
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• 2006

An experiment was conducted to study the effect of temperature and pH on in vitro nutrient degradability, volatile fatty acid profile and methane production. The fermenter used was the semi-continuous system, known as the rumen simulation technique (RUSITEC). Sixteen cylinders were used at one time with a volume of 800 ml, the dilution rate was set at 3.5%/hour, the infused buffer being McDougall's artificial saliva. Basal diet (9.6 g DM) used in RUSITEC consisted of (DM) 6.40 g Timothy hay, 1.86 g crushed corn and 1.34 g soybean meal. The food for the fermentation vessel was provided in nylon bags, which were gently agitated in the liquid phase. The experiment lasted for 17 d with all the samples taken during the last 5 d. Treatments were allocated at random to four vessels each and were (1) two temperature levels of $39^{\circ}C$ and $41^{\circ}C$ (2) two pH levels of 6.0 and 7.0. The total diet contained ($g\;kg^{-1}$ DM) 957 OM, 115 CP and $167MJ\;kg^{-1}$ (DM) GE. Although increase in temperature from $39^{\circ}C$ to $41^{\circ}C$ reduced degradation of major nutrients in vitro, it was non-significant. Interaction effect of temperature with pH also reflected a similar trend. However, pH showed a significant (p<0.05) negative effect on the degradability of all the nutrients in vitro. Altering the in vitro pH from 7 to 6 caused marked reduction in DMD from 60.2 to 41.8, CPD from 76.3 to 55.3 and GED from 55.3 to 35.1, respectively. Low pH (6) depressed total VFA production (61.9 vs. 34.9 mM) as well as acetate to propionate ratio in vitro (from 2.0 to 1.5) when compared to pH 7. Compared to pH 7, total gas production decreased from 1,841 ml to 1,148 ml at pH 6, $CO_2$ and $CH_4$ production also reduced from 639 to 260 ml and 138 to 45 ml, respectively. This study supported the premise that pH is one of the principal factors affecting the microbial production of volatile fatty acids and gas. Regulating the ruminal pH to increase bacterial activity may be one of the methods to optimize VFA production, reduce methane and, possibly, improve animal performance.

• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1466-1473
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• 2013

This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

• 한국농림기상학회지
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• 제5권2호
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• pp.87-93
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• 2003

산림생태계에서 낙엽낙지의 유입과 유입된 낙엽낙지의 분해는 산림의 주요한 탄소 및 양분의 공급원이다. 본 연구는 온대중부지역에 속하는 경기도 광릉의 천연 활엽수림에 위치한 DK-site를 대상으로 2년 동안 연 낙엽낙지 유입량과 낙엽분해율을 측정하였다. 낙엽낙지량은 원형의 낙엽수집기(수집면적 0.25$m^2$)를 낙엽분해 율은 10${\times}$30 cm 크기의 낙엽분해주머니(메쉬 1.5 mm)를 이용하였다. 광릉 장기생태연구조사구의 연 낙엽낙지량은 5,627 kg/ha/yr로 이중 순수한 엽량은 총 낙엽낙지량의 61%를 차지하였다. 수종별 유입량은 본 조사구의 우점종인 졸참나무 잎이 가장 많은 양을 보였으며 서어나무, 까치박달 순이었다. 낙엽분해율은 서어나무, 까치박달 낙엽이 졸참나무 낙엽에 비해 분해속도가 빨라 2년의 조사기간 동안 까치박달 낙엽 84%, 서어나무 낙엽 77%, 졸참나무 낙엽 48%가 분해되었다. 졸참나무 낙엽의 분해가 느리게 진행된 것은 타수종의 낙엽에 비해 졸참나무 낙엽내 낮은 양분함량 같은 기질의 차가 원인인 것으로 나타났다. 칼륨을 제외한 양분(N, P, Mg)함량은 분해 초기함량에 비해 낙엽분해과정동안 증가하였다. 또한 낙엽분해과정동안 양분(N, P, K, Ca, Mg)의 방출량은 까치박달과 서어나무낙엽이 졸참나무낙엽에 비해 신속한 것으로 나타났다. 본 연구결과에 따르면 광릉장기생태연구 조사구내 우점종의 낙엽분해와 양분의 동태는 동일한 입지에 있어서도 수종간에 상당한 차이를 나타내었다.

• 한국식품저장유통학회지
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• 제24권8호
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• pp.1060-1066
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• 2017

어린 감 과실의 활용과 쌀쿠키의 고부가가치화를 위해, 밀가루나 글루텐 무첨가 쌀쿠키의 품질특성에 어린 감 분말의 첨가가 미치는 영향을 규명하였다. 쌀쿠키는 쌀가루 대비 감 분말을 0, 1.5, 3, 6 및 12%를 각각 첨가하여 반죽을 한 다음 두께 3 mm 직경 35 mm 원판으로 성형한 후 $170-180^{\circ}C$ 오븐에서 굽고 그의 품질특성을 조사하였다. 손실률과 퍼짐성 지수는 감 분말첨가량에 따라 증가 후 감소하는 경향을 보였다. 수분함량과 수분활성도는 감 분말 첨가량에 비례하여 높아짐을 나타내었다. 색도 $L^*$값과 $a^*$값은 감 분말 첨가량의 증가와 함께 증가됨을 보였다. 총페놀 함량과 DPPH 유리기 소거능은 감 분말 첨가량에 따라 증가하는 경향을 보였으며 특히, DPPH 유리기 소거능은 첨가량 3%에서 큰 폭으로 증가함을 보였다. 따라서 어린 감 과실 분말첨가가 쌀쿠키의 이화학적 품질특성에 미치는 영향이 확인되었고, 쌀쿠키의 일반 품질특성 저하 없이 항산화능 증대효과를 얻을 수 있는 감 분말의 첨가량은 3% 정도인 것으로 판단되었다.

• 한국습지학회지
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• 제17권2호
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• pp.203-208
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• 2015

벚나무류가 식재된 인공 연못에서 벚나무류의 낙화가 연못생태계의 물질순환에 어떠한 영향을 미치는지 확인하기 위해 벚꽃이 분해되는 기간을 달리하여 마이크로코즘 실험을 수행하였다. 벚나무류의 꽃잎을 넣은 망(mesh)의 크기가 $1mm^2$인 나일론 꽃잎주머니를 제작하였다. 플라스틱 통을 하나의 마이크로코즘 단위로 하여 인공 연못의 유입수를 채우고, 꽃잎주머니를 넣은 처리구와 넣지 않은 대조구를 설정하였다. 처리구에서 꽃잎주머니를 수거하는 시기를 달리한 결과, 실험이 끝난 후 벚꽃잎은 초기 건중량의 32.3%만이 남았으며, 분해율(k)은 $7.06{\times}10^{-2}day^{-1}$로 나타났다. 벚꽃잎이 분해된 물의 $NO_3-N$ 농도는 1.90 mg/L에서 처음 4일 후 급격히 감소하여 0.02 mg/L를 나타낸 반면, $NH_4-N$ 농도는 0.03 mg/L에서 분해가 진행되는 동안 계속적으로 증가하여 2.85 mg/L를 나타냈다. $PO_4-P$ 농도는 0.03 mg/L에서 꽃잎의 분해에 의해 2.39 mg/L까지 증가하여, 인이 질소에 비해 상대적으로 높은 비율이 무기형태로 용탈되고 있음을 알 수 있다. 인공 연못에 쌓이는 벚꽃의 양을 추산하고 용탈되는 가용성 질소와 인의 양을 예상한 결과, 벚꽃잎이 분해되어 물에 녹아나온 가용성 인은(0.02 mg/L 증가) 인공 연못의 부영양화를 유발할 수 있는 것으로 판단된다.