• Journal of Ecology and Environment
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• 제40권2호
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• pp.89-106
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• 2016

Many plant species have two modes of reproduction: sexual and asexual. Both modes of reproduction have often been viewed as adaptations to temporally or spatially variable environments. The plant should adjust partitioning to match changes in the estimated success of the two reproductive modes. Perennial plants showed that favorable habitats in soil nutrients or water content tend to promote clonal growth over sexual reproduction. In contrast, under high light-quantity conditions, clonal plants tend to allocate more biomass to sexual reproduction and less to clonal propagation. On the other hand, plants with chasmogamous and cleistogamous flowers provides with a greater tendency of the opportunity to ensure some seed set in any stressful environmental conditions such as low light, low soil nutrients, or low soil moisture. It is considered that vegetative reproduction has high competitive ability and is the major means to expand established population of perennial plants, whereas cleistogamous reproduction is insurance to persist in stressful sites due to being strong. Chasmogamous reproduction mainly enhances established and new population. Therefore, the functions of sexual and asexual propagules of perennial or annual plants differ from each other. These traits of propagule thus determine its success at a particular region of any environmental gradients. Eventually, if environmental resources or stress levels change in either space or time, species composition will probably also change. The reason based on which the plants differ with respect to favored reproduction modes in each environmental condition, may be involved in their specific realized niche.

• 한국초지조사료학회지
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• 제14권1호
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• pp.27-33
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• 1994

This study was conducted to determine the nutritional value of native oriental white oak(Quercus aliena Blume) browse by Korean native goats. Oak browse were mixed with grass hay(orchardgrass 60% and red clover 40%), varing in oak browse content. Diets included 30% oak browse and 70% grass hay, 60% oak browse and 40 % grass hay, and a 100% grass hay(contro1). Oak browse diets were higher in NDF, ADF, lignin, and tannin contents, but lower in CP content than the control diet with increased oak browse levels. Gross energy levels showed no difference between the control and oak browse diets. Dry matter intake was the lowest on diet containing oak browse 60%. Digestibility for DM, cellular constituents, NDF, and ADF showed lower for oak browse diets compared to control diet(P<0.05). Oak browse diets furnished significantly lower dietary N than &d the control diet. Fecal N losses generally increased with higher levels of oak browse levels(P<0.05). Apparently digested N and retained N were lower in oak browse diets than in control diet. The higher retained N was obtained in control diet than in oak browse diets. DE and ME declined linearly as oak browse levels increased when compared to control diet(P

• 한국토양비료학회지
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• 제16권2호
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• pp.98-105
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• 1983

토양수분조건에 따른 시비반응을 구명(究明)하기 위하여 본량(本良) 사양토(砂壤土)에서 토양수분처리($M_0$무관수, $M_1$-0.1~-1.0bar, $M_2$-0.1bar~-0.5bar, $M_3$-0.1~-0.2bar)와 시비수준(施肥水準)(N-P-Kkg/10a, 0-0-0, 11.5-10-12.5, 23-20-25, 34.5-30-37.5)을 달리하여 봄배추의 생육상태(生育狀態), 물소모량(消耗量), 양분흡수량, 비료이용율(肥料利用率), 수량 등을 조사(調査)한 결과(結果)는 다음과 같다. 1) 20cm 깊이에서 토양수분 Potential이 -2.0bar 이하(以下)일 때 물소모량은 감소(減少)하였고 비료(肥料)에 의(依)한 생장량(生長量)의 증가는 없었다. 2) 배추의 양분흡수량(養分吸收量)은 시비량(施肥量)의 증가에 따라 토양수분 Potential이 낮을 때는 감소(減少)하는 경향(傾向)이었고, 토양수분 Potential이 높을 때는 증가하는 경향(傾向)이었다. 3) 질소(窒素)와 가리(加里)의 이용율(利用率)은 토양수분 Potential과 시비수준(施肥水準)이 정비례관계(正比例關係)에 있어야 이용율(利用率)이 증대되었다. 4) 봄배추의 수량(收量)은 토양수분 Potential이 낮을 때에는 시비량(施肥量)을 증가시켜도 증수가 없었으며, 토양수분 Potential이 높을 때에는 각(各) 시비수준(施肥水準) 공(共)히 증수효과(增收效果)가 있었고 그 효과(效果)는 다비수준(多肥水準)에서 더욱 뚜렷하였다. 5) 토양수분 Potential을 높게 유지(維持)시킬 경우(境遇)에는, 시비량(施肥量)을 증가시킴에 따라 봄배추 수량(收量)이 거의 직선적(直線的)인 증가경향을 보여, 최대수량을 낼 수 있는 비료요구량(肥料要求量)이 크게 증가되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.368-375
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• 2006

Four rumen-fistulated dairy steers were randomly assigned according to a $4{\times}4$ Latin square design to investigate effects of supplementation levels of sodium dl-malate in concentrates on rumen ecology, ruminal fermentation, nitrogen balance, feed intake and digestibility of nutrients and ruminal microbial protein synthesis. The dietary treatments were cassava concentrate-based, containing sodium dl-malate supplementation at 0, 9, 18 and 27 g/hd/d with urea-treated rice straw (UTS) fed ad libitum. The experiment was conducted for four periods, each period lasting 21 days. Ruminal pH increased with incremental addition of malate (p<0.05). Additionally, molar proportions of propionate were higher in supplemented groups and was highest at 18 g/hd/d of malate supplement (p<0.05). Microbial protein synthesis tended to be higher in dairy steers receiving sodium dl-malate supplements and also was the highest at 18 g/hd/d. Variable bacterial populations, such as amylolytic, proteolytic and cellulolytic species were increased (p<0.05). Furthermore, protozoal populations were decreased significantly (p<0.05), while fungal zoospores were dramatically increased in dairy steers receiving sodium dl-malate supplement (p<0.05). These results suggested that supplementation of concentrate containing a high level of cassava chip at 18 g/hd/d with UTS in dairy steers could improve rumen fermentation efficiency and rumen microbial protein synthesis.

• Journal of Ecology and Environment
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• 제43권4호
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• pp.461-468
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• 2019

Background: This study aimed to identify NO₃^--N sources using the stable isotope δ¹⁵N in Chydorus sphaericus (OF Müller), to investigate hydrological characteristics and nutrient states in artificial wetlands near the Nakdong River. Chydorus sphaericus is dominant in wetlands where aquatic plants are abundant, occurring in high density, and is sensitive to wetland water pollution, making it suitable for identification of NO₃^--N sources. Results: NO₃^--N sources for each wetland were strongly dependent on hydrological characteristics. Wetlands with sewage or rainfall/groundwater as their main sources had high levels of NO₃^--N, whereas wetlands with surface water as their main input had comparatively lower levels. Since wetlands with sewage and rainfall/groundwater as their main water sources were mostly detention ponds, their inputs from tributaries or the main river stream were limited and nutrients such as NO₃^--N easily become concentrated. Changes in NO₃^--N levels at each wetland were closely associated with δ¹⁵N of C. sphaericus. Interestingly, regression analysis also showed positive correlation between δ¹⁵N of C. sphaericus and NO₃^--N level. Conclusions: We conclude that the nitrate stable isotope (δ¹⁵N) of C. sphaericus can be used to elucidate the hydrological characteristics of riverine wetlands. This information is important for maintenance and conservation of artificial wetlands at the Nakdong River.

• 대한지역사회영양학회지
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• 제16권1호
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• pp.51-61
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• 2011

Elevated serum concentration of inflammation markers is known as an independent risk factor of metabolic syndrome (MS) and dietary intake is an important factor to control MS. The purpose of this study was to investigated the hypothesis that inflammatory indices are associated with dietary intake and diet quality index-international (DQI-I) in subjects with MS. A cross-sectional study was conducted on 156 men and 73 postmenopausal women with MS, defined by three or more risk factors of the modified Adult Treatment Panel III criteria. Serum levels of high sensitive C-reactive protein (hs-CRP), adiponectin were examined and nutrients intake and DQI-I were assessed using a semiquantitative food frequency questionnaire. The total DQI-I score was significantly higher in female subjects ($65.87{\pm}9.86$) than in male subjects ($62.60{\pm}8.95$). There was a positive association between hs-CRP and polyunsaturated fatty acid intake (p < 0.05) and a negative association between adiponectin and lipid (p < 0.05), total sugar (p < 0.01), and total fatty acids (p < 0.05). When the subjects were divided into 5 groups by quintile according to serum adiponectin and hs-CRP level, there was no association between DQI-I score and hs-CRP levels. Moderation score of DQI-I was significantly higher in highest quintile group than the lower quintile groups. Therefore, our results provide some evidence that dietary intake and diet quality are associated with inflammation markers and dietary modification might be a predictor to decrease risk for metabolic syndrome complications. However further research is needed to develop the dietary quality index reflecting the inflammatory change by considering the dietary habit and pattern of Koreans.

• Journal of Nutrition and Health
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• 제27권8호
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• pp.837-843
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• 1994

The relationships among physical growth, dietary intakes, and Zn & Cu status were investigated in total of 128 eight-year-old children selected from the primary school in Seoul. The mean weight and height were 28.3Kg and 129.6cm and the average BMI and R hrer index were 16.75 and 129.25. These values were a little higher than the ones for the average Korean children at the same age. The average serum Zn & Cu levels were 109.98$\mu\textrm{g}$/100ml and 84.13$\mu\textrm{g}$/ml. About 2.4% of the subjects had blood Zn level below the normal range and 8.6% had above the normal level. For Cu, about 43% of the subjects fell into the subnormal level. Daily dietary intakes of calorie, protein and ascorbic acid were relatively adequate but Fe, thiamin, riboflavin, and niacin were insufficient. Ca and vitamin A intakes were very poor. More than 50% of the subjects onsumed Ca and vitamin A less then 2/3 of RDA. There was no consistant relationship among the serum Zn and Cu levels, growth, and the nutrients intakes. But it was observed that serum Zn contents were higher as consumption of milks, fats and oil groups were high in the serum Zn contents were higher as consumption of milks, fats and oil groups were high in the several BMI groups, and lower in taller and heavier children within the group of 110-119% BMI rate. Therefore, it could be summarized that the Zn status of the children was favorable but the Cu status was inadequate. Serum Zn and Cu levels were found to be related to the overall quality and/or the quantity of diet and physical growth pattern of children.

• 한국수산과학회지
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• 제48권2호
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• pp.187-192
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• 2015

The dietary fiber alginic acid has no nutritional value; however, it decreases the utilization of nutrients by the body and can prevent obesity, hyperlipidemia, arteriosclerosis, constipation, and colon cancer. The low-molecular-weight alginic acid polymannuronate improves serum and liver lipid metabolism by decreasing cholesterol levels in high-cholesterol groups and may be used to control high blood pressure. Previously, we showed that polymannuronate, a physiologically active agent from seaweed, has a lipid-lowering effect and preventative role in colon cancer. In addition, the differentiation of polymannuronate-treated adipocytes was inhibited, triggering decreased leptin expression. This study examined ways to increase dietary satisfaction with and improve the nutritional quality of polymannuronate using hamburger buns supplemented with polymannuronate. Twenty male Sprague-Dawley rats were divided into two groups: the control group was fed hamburger buns containing 6% gluten, while the experimental group was fed hamburger buns containing 6% gluten and 10% polymannuronate. The serum triglyceride, phospholipid, and total and free cholesterol levels of the rats in the experimental group were decreased compared with those of the controls. The serum aspartate aminotransferase activity levels did not differ between the two groups. This study demonstrates that polymannuronate has beneficial effects on lipid metabolism and may be commercially useful.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1084-1091
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• 2007

Different levels of dietary mannanoligosaccharide (Bio-MOS, Alltech Inc.) were evaluated for their efficacy on performance and gut development of broiler chickens during a 6-week experimental period. Experimental diets contained (g MOS/kg diet) a low (0.5 g during the entire period), medium (1 g during the entire period), high (2 g during the entire period), or step down (2 g in the first week; 1 g in the second and third week; 0.5 g in the last three weeks) level of MOS. Control diets included a negative and a positive control (zinc bacitracin, ZnB, 50 ppm and 30 ppm in the first and last three weeks, respectively). MOS supplementation improved the growth performance of young birds and the effects became less when the birds got older. The growth response of birds was more obvious at the high dosage level of MOS treatment than the other MOS treatments and the growth performance of birds fed on the high MOS diet was comparable to that of birds fed on the ZnB diet. Depending on the dosage level and the age of birds, MOS seemed to reduce the size of the liver and the relative length of the small intestine but did not affect the relative weight of the other visceral organs (proventriculus, gizzard, pancreas, bursa and spleen) and that of the small intestine. A numerical increase in the small intestine digestibility of nutrients was noticed in the young birds fed on the MOS diet(s), but not in the older ones. Medium and/or high MOS treatment also increased the villus height of the small intestine of birds at different ages. Similar results were observed on the ZnB treatment. However, MOS and ZnB affected caecal VFA profile in different ways. MOS increased, or tended to increase, whereas ZnB reduced individual VFA concentrations in the caeca.

• Asian-Australasian Journal of Animal Sciences
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• 제13권4호
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• pp.483-486
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• 2000

The influence of feed allowance on intake and nutrient utilization by Barbari goats given green maize (Zea mays) and potential feeding value of left-overs were studied. The goats were offered food at 3 levels to give left-overs of about 20% (T-1), 35% (T-2) and 50% (T-3) DM of offered amount. A marked effect of refusal rate on intake and digestibility of nutrients was found. The DMI, g/kg $W^{0.75}$ increased from 39.86 in T-1 to 50.91 and 66.55 g in groups T-2 and T-3, respectively. Allowing selective consumption at higher levels (T-2 and T-3), the intake of TDN and DCP from green maize was found not only to meet the maintenance requirement but provided surplus energy and protein for substantial production. The variability in diet selectivity between goats under different treatments was pronounced. As the level of food excess increased to T-3, the left overs had a higher IVDMD and crude protein and decreased cell wall constituents (p<0.05). Considering the substantial increase in intake and digestibility from feeding green maize at high allowances to goats, further studies are needed to develop practical feeding strategies.