• 한국잠사곤충학회지
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• 제31권1호
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• pp.12-19
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• 1989

추기 된서리로 인한 자연낙엽에 관계없이 상묘를 굴취할 수 있도록 하기 위하여 1985년부터 2년간 전국 각도 9개 지역에서 9월 30일부터 11월 20일까지 10일 간격으로 6회에 걸쳐 굴취하여 묘질을 분석한 결과 다음과 같았다. 1. 묘목의 굵기는 10월 30일까지 다소의 증가를 보였다. 2. 조기굴취는 그루당 새순의 수와 길이를 떨어뜨렸으며, 10월 30일 굴취구에서 생육이 가장 양호하였다. 3. 10월 20일 이후는 자연낙엽에 관계없이 굴취하여도 활착율과 생육에 영향을 주지 않았다. 4. 굴취시기를 늦을수록 체내에 전실소와 P함량이 증가되는 반면 K는 감소하였으며 Ca는 일정하지 않았다. 5. 전실소, P, Ca 등은 뿌리껍질에서 보다 줄기껍질에 함량이 높았으며 K는 일정하지 않았다.

• 한국초지조사료학회지
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• 제16권3호
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• pp.219-224
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• 1996

Silage comkv, suwwn 19). sorghum $\times$ sudangrass(p. 988) and winter ryeNaton) were cultivated on imperfectly drained paddy field under two different draining methods, subsurface darinage by PVC pipes and open ditsched surface drainage. The crops were harvested at the stage of hard dough for corn and soft dough for wrghum and rye. The soil physical properties. soil colors. soil structure and soil wetness were improved in the subsurface drainage. Gravitational water table occured depth in 110 cm(dry season)~75cm(rain season). In soil profile description, yellowish brown with yellowish red mottles and well developed granular structure were found in the surface A horizon. The portion of solid phase in subsoils(B horizon) was reduced from 48.6%(undrained) to 43.7 %. A blocky structure with dark gray to gray were described in the open ditsched surface drainage. Severe wet depression of the crops was observed due to it's higher moisture contents, where the gravitational water occured depth in 25~37cm during the rainy season. The chemical properties of paddy soils were less affected by drainage methods. The concentration of available phosphate. organic matter and exchangeable K, Ca and Mg were decreased in the subsurface drained soils. The annual dry matter yields of com-rye cropping were 17.8 ton in the undrained, 21.6 ton in the open ditsch drainage and 35.9 ton/ha in the subsurface drainage.

• 한국농공학회논문집
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• 제52권4호
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• pp.63-71
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• 2010

This study was performed to evaluate the planting properties and root potential of planting block with mixing seeding of herbaceous plants and cool-season grasses in CSG blocks manufactured by cemented sand and materials (CSG) in order to develop environmentally friendly CSG block applied revegetation. Five types of CSG mix designs with cement contents were determined, and the mechanical properties of CSG materials were studied experimentally. To analyze growth properties of plants within CSG block, germination ratio, visual cover, plant height and root potential were measured in four weeks and eight weeks after seeding. The germination regardless mixture seeding of plants and CSG mixproportions started within 4 ~ 7 days after seeding and the germination ratio were in the range of 60 ~ 65 %. The visual cover of kinds of plants evaluated by visual rating system were in the range of 6 ~ 8 in case of seeding the species of cool-season grasses and were in the range of 4 ~ 6 in case of seeding the species of herbaceous plants in four weeks after seeding. The root potential of CSG block with the species of cool-season grasses and herbaceous plants were in the range of $5.7{\times}10^{-3}{\sim}7.7{\times}10^{-3}$ MPa and $2.3{\times}10^{-3}{\sim}6.7{\times}10^{-3}$ MPa in eight weeks after seeding, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1222-1227
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• 1999

Effect of three major cropping seasons and five fertilizer treatments on botanical composition, nutritional composition and in sacco digestibility of native grasses grown in 30 experimental plots of a medium fertile land was determined. It was observed that all the major grass species were grown in all seasons but their predominancy of growth was different. During the study the predominant grass species were Panicum repens (Angta), Fimvristylis miliacea (Joina), Cyanolis axillaries (Kanainala), Cynodon dactylon (Durba) and Cyperus iria (Phulchaise) which contributed about 27, 20, 13, 11 and 9% of the total grass yield, respectively. Dry matter (DM) contents was higher in dry followed by monsoon and summer seasons (p<0.05). Crude protein (CP) content in the summer and monsoon appeared to be higher (p<0.05) than that of dry season. Organic matter (OM) and neutral detergent fibre (NDF) were higher (p<0.05) in dry and monsoon than in summer season. Application of urea fertilizer and cowdung increased 28.2% of CP content of the grasses, but decreased 19.5 and 9.8% of DM and NDF contents, respectively. The potential degradation of DM and CP of the grasses grown in summer were 4.1 and 8.4% and 3.9 and 5.8% higher than those of monsoon and dry seasons, respectively, and both of these increased (11.3 and 5.9%, respectively) with the application of cowdung and urea fertilizer.

• 한국초지조사료학회지
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• 제13권4호
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• pp.257-267
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• 1993

본 시험은 여름철 고온기간중 예취시기와 예취높이가 orchardgrass의 목초 재생과 저장탄수화물 함량 및 수량에 미치는 영향을 구명하기 위하여 실시되었다. 시험설계는 3차 예취시기(7월 15일, 7월 25일, 8월 5일)를 주구, 3차 예취시 예취높이(3, 6. l0cm)를 세구로 하여 분할구 배치 3 반복으로 하여 1988년 장성실업고등학교 포장에서 수행되었다. 1. 고온기의 예취높이별 지표 및 지중(l0cm) 온도는 7월 15일 예취구와 7월 25일 예취구에서는 뚜렷한 차이를 보이지 않고 있는데 이는 장마의 영향으로 보이며, 8월 5일 예취구에 있어서 지표 및 지중온도는 여름철 예취높이가 높을수록 낮아지는 경향을 보였다. 2. 고온기 예취높이별 토양수분 함량의 변화는 예취높이가 높아질수록 토양수분 함량은 낮아지는 경향을 보였다. 3. 고온기 예취높이별 재생초장, 재생엽장 및 재생엽면적의 변화는 예취높이가 높을수록 생육속도가 빨라졌다. 4. 고온기 예취시기와 예취높이가 그루터기의 저장탄수화물 함량에 미치는 영향은 7월 15일과 7월 25일 예취구가 8월 5일 예취구에 비해 저장탄수화물이 예취전 상태로 회복되는 일수가 빨랐으며 저장탄수화물 축적량도 많았다. 5. 고온기 건물수량은 3차 예취시 8월 5일 예취구가 7월 15일과 7월 25일 예취구 보다 더 많았고 예취높이 3cm구가 6cm구와 l0cm구 보다 더 많았다. 그러나 4차 및 5차 예취시 건물수량은 7월 15일 예취구가 7월 25일과 8월 5일 예취구에 비하여 현저히 많았다. 본 시험의 결과를 종합하여 볼 때 여름철 고온기의 유리한 초지관리를 위해서는 예취시기에 관계없이 고온기 예취높이가 l0cm인 시험구가 재생, 탄수화물 축적 및 건물 생산량에서 바람직한 결과를 나타냈다.에 관계없이 무처리에 비해 발아율이 향상되었다. 평균발아 소요일수에 있어서도 Kinetin 과 NAA는 무처리보다 지연되는 경향이었으나 GA$_3$는 100 ppm 전처리시 무처리 대비 2.0일이 단축되었다. 6. PEG나 GA3의 종자 전처리는 수분장애 조건에서 공히 무처리에 비해 발아율이 향상되었고 평균발아 소요일수도 단축되어, 수분장애시 오차드그라스의 균일한 발아 유도와 발아속도를 개선하는데 효과가 있을 것으로 생각되나, 어떠한 처리에 있어서도 대조구의 무처리구 발아율(79.0%)을 능가하지 못하여 오차드그라스의 발아에 관한 수분장애 요소를 완전히 극복할 수는 없었다.>, $C_{l8:2}$, $C_{l8:1}$, $C_{18:2}$ 등이 주요 지방산으로 조직에 따라 약간씩 다른 경향을 보였다. 그리고 카테킨은 특히 혈청에서 $C_{20:5}$, $C_{22:6}$과 같은 고도불포화지방산의 함량을 유지시키는데 효과적임을 알 수 있었다. 이상의 결과를 미루어 볼 때 과산화된 지질의 섭취는 생체내 대사 이상을 유발할 가능성이 인식되었고 카테킨의 투여는 신선한 어유를 섭취한 경우 뿐만 아니고 이미 과산화된 어유를 섭취한 경우 뿐만 아니고 이미 과산화된 어유를 섭취한 경우에도 생체내에서 과산화 억제작용을 어느 정도 효과적으로 수행하는 것으로 나타나 앞으로 이의 효과적인 활용이 기대된다.다.nsidered to be due to the different food habits and environmental condition of the invertebrates.재강조될 필요가 있다. 이 두 역할개념 들을 교육을 통하여 효과적으로 가르칠

• The Korean Journal of Ecology
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• 제26권4호
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• pp.189-197
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• 2003

남한산성 지역에서 춘계단명식물인 현호색 자연집단에 대해 2년간 종자생산의 특성을 조사하였다. 개화는 4월초에, 종자생산은 5월초에 일어나 개화로부터 종자생산까지는 30일이 소요되었으며 생식기관의 수가 감소하는 시기는 낙화 및 결실기 사이가 가장 큰 것으로 나타났다. 개체 당 생산하는 꽃의 수는 1∼13개, 종자의 수는 0∼76개, 열매 당 종자의 수는 0∼20개이었다. 한 개체 내에서 열매 당 종자생산량은 가장 아래에 위치한 꽃이 11.8개로 많았으며 상부로 이행할수록 급격히 감소하였다. 동일한 개체가 생산하는 종자의 수는 매년 큰 폭으로 변하였으며 작은 개체는 다음해 많은 수의, 큰 개체는 적은 수의 증자를 생산하였다. 생육초기 개화체의 비율은 개체의 크기(괴경의 부피)가 증가할수록 증가하였으며 가장 작은 크기 계급인 <100 ㎣에서 5.0%(1999)∼5.4%(2000)를, 600㎣≤ 에서 100%를 나타냈다. 한편, 각 계급별 평균 꽃의 수는 2000년이 1999년보다 많았다. 특히 900 ㎣≤에서는 6.5개(1999)와 13.2개(2000)로 현저한 차이를 보였다. 생육후기 개화체의 비율은 <100 ㎣에서 13.3%이었고 500 ㎣≤ 에서 100%이었다. 따라서 생육초기보다 개화체의 비율이 다소 높게 나타났다. 괴경의 체적이나 건중량의 크기에 따른 열매의 수 및 종자의 수는 대체로 증가하였지만 경향성은 뚜렷하지 않았고 동일 크기계급 내에서도 개체마다 편차가 심하였다. 한편, 엽면적이 증가할수록 열매의 수나 종자의 수는 뚜렷이 증가하였다. 따라서 종자의 생산량은 생육기간동안 광합성량과 관계가 깊은 것으로 볼 수 있었다.

• Fisheries and Aquatic Sciences
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• 제8권2호
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• pp.65-69
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• 2005

We evaluated the effects of the partial dietary replacement of fish meal with squid liver $Meal^{TM}$ on the growth and body composition of juvenile olive flounder Paralichthys olivaceus during the winter season. Twenty-five fish with an initial body weight of 23 g per tank were distributed among 12,250 L flow-through tanks. The experimental diets, which were designated SLM5, SLM1O, and SLM15 diets, were prepared in triplicate along with control diet by replacing 5, 10, and $15\%$ of mackerel fish meal with squid liver $Meal^{TM}$, respectively. The weight gain and specific growth rate of flounder that were fed the control and SLM5 diets did not differ from those of the fish fed the SLM10 diet, but they were significantly (P<0.05) higher than those of the fish fed the SLM15 diet. The feed efficiency ratios for the flounder that were fed the control, SLM5 and SLM10 diets were significantly (P<0.05) higher than for the fish that were fed the SLM15 diet. However, the protein efficiency ratio for the flounder was not significantly affected by the experimental diets. The crude protein, crude lipid and ash content, and blood chemistry of the flounder were not significantly affected by the experimental diets. Therefore, the replacement of up to $10\%$ of dietary fish meal with squid liver $Meal^{TM}$ can be made without a reduction in growth or a deterioration of the feed efficiency of juvenile olive flounder during the winter season.

• 한국양식학회지
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• 제2권2호
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• pp.91-106
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• 1989

해산어류 및 갑각류 유생 사육 시 초기 먹이로 요구되는 rotifer를 고온기나 저온기에 생산하고자 할 때 Chlorella 대용으로서 적합한 식물성 먹이생물에 관한 실험요약은 다음과 같다. 1. 고온에서 가장 성장이 양호한 종은 Nannnochioris oculata로 $28^{\circ}C$, $33\%_{\circ}$, 5,000 lux가 최적 환경 요인으로 밝혀졌다. 2. 저온에서 가장 성장이 양호한 종은 Phaeodactylum tricornutum이었고 이 종의 최대 성장요인은 보험구간중 가장 고온인 $10^{\circ}C$, 8,000 lux 및 $30\%_{\circ}$이었고 $8^{\circ}C$에서도 성장이 양호한 편이었다. 3. Nannnochioris oculata 와 Phaeodactylum tricornutum을 대조구인 Chlorella ellipsoidea와 함께 고온 및 저온에서 각각 대량배양하여 rotifer를 배양한 결과 rotifer 개체 밀도는 Nannnochioris oculata를 공급하여 배양한 것이 Chlorella ellipsoidea에 비해 월등히 높았고 Phaeodactylum tricornutum을 공급하여 배양한 경우는 Chlorella ellipsoidea보다 약간 낮은 것으로 나타났다. 지방산 조성에서도 Nannnochioris oculata가 Chlorella ellipsoidea나 Phaeodactylum tricornutum보다 polyene의 비가 높아 영양적인 측면에서도 유리한 것으로 확인되었다.

• Fisheries and Aquatic Sciences
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• 제23권6호
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• pp.16.1-16.10
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• 2020

This study was conducted in Lake Hayq between January and December 2018. The objectives of this study were to determine the growth, condition, sex ratio, fecundity, length at first sexual maturity (L₅₀), and spawning seasons of common carp (Cyprinus carpio). Monthly fish samples of C. carpio were collected using gillnets of stretched mesh sizes of 4, 6, 7, 8, 10, and 13 cm and beach seines of mesh size of 6 cm. Immediately after the fish were captured, total length (TL) and total weight (TW) for each individual were measured in centimeters and grams, respectively, and their relationship was determined using power function. Length at first maturity (L₅₀) was determined for both males and females using the logistic regression model. The spawning season was determined from the frequency of mature gonads and variation of gonadosomatic index (GSI) values of both males and females. Fecundity was analyzed from 67 mature female specimens. The length and weight relationship of C. carpio was TW = 0.015TL^2.93 for females and TW = 0.018TL^2.87 for males that indicate negative allometric growth in both cases. The mean Fulton condition factor (C_F) was 1.23 ± 0.013 for females and 1.21 ± 0.011 for males. The value of C_F in both cases was > 1 that shows both sexes are in good condition. Among the total 1055 C. carpio collected from Lake Hayq, 459 (43.5%) were females and 596 (56.5%) were males. The chi-square test showed that there was a significant deviation between male and female numbers from 1:1 ratio (χ²= 22, df = 11, P > 0.05) within sampling months. The length at first sexual maturity (L₅₀) for females and males were 21.5 and 17.5 cm, respectively. Males mature at smaller sizes than females. The spawning season of C. carpio was extended from February to April, and the peak spawning season for both sexes was in April. The average absolute fecundity was 28,100 ± 17,462. C. carpio is currently the commercially important fish while Nile tilapia fishery has declined in Lake Hayq. Therefore, this baseline data on growth, condition, and reproductive biology of common carp will be essential to understand the status of the population of carp and design appropriate management systems for the fish stock of Lake Hayq, Ethiopia, and adjacent countries.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.229-234
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• 2002

Possibility of raising sunshine bass during the winter season in Korea was investigated. Also, the effect of feed on growth and body composition of sunshine bass was compared at the various salinity. Twenty sunshine bass $(Mean\;weight\;\pm S.D.\: :\;53.9 \pm 0.24 g)$ were stocked into the eighteen circular flow-through tanks. A 2 (feed) $\times$ 3 (salinity) factorial design with triplicate was used for this study. Feed was prepared into the 2 groups: the raw fish-based me>ist pellet (MP) containing $59.5\%$ crude protein and $9.4\%$ crude lipid, and commercial sinking red sea bream feed (CF) containing $49.9\%$ crude protein and $9.4\%$ crude lipid, respectively. And salinity was prepared into the 3 groups: freshwater $(0\%)$, brackishwater $(15\%)$, and seawater $(32\%)$. Fish were fed to satiation twice daily for 6 days a week. Fish were all survived at the end of the 8-week feeding trial. Weight gain (WG) and specific growth rate (SGR) of sunshine bass were significantly (P<0.05) affected by both feed and salinity. WG and SGR of sunshine bass fed the MP were significantly (P<0.05) higher than those of fish fed the CF in the same salinity. Amount of dry feed fed was significantly (P<0.05) affected by both feed and salinity. Feed consumption by sunshine bass fed on the MP was significantly (P<0,05) higher than by fish fed on the CF in the same salinity. Feed efficiency ratio (FER) was significantly (P<0,05) affected by salinity, but not by feed. Protein efficiency ratio (PER) was significantly (P<0.05) affected by both feed and salinity. Moisture and protein content of the whole-body of fish was not significantly (P>0.05) affected by either feed or salinity. However, lipid and ash content of the whole-body of fish was significantly (P<0.05) affected by salinity, but not by feed. In conclusion, the MP was superior to CF for growth of sunshine bass during the winter season in Korea and no mortality occurred. And sunshine bass seemed to grow better in freshwater $(0\%)$ and brac-kishwater $(15\%)$ than seawater $(32\%)$ under these experimental conditions, in terms of improvement in FER and PER in freshwater or brackishwater.