• Fisheries and Aquatic Sciences
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• 제26권8호
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• pp.482-490
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• 2023

Food and feeding habits of Labeobarbus intermedius were studied from the newly constructed Ribb Reservoir, Ethiopia during the dry (December-March) season and wet season (June-August) of 2021. The objective of the study was to determine the diet composition, seasonal variation, and ontogenetic dietary shift in the diets of the dominant cyprinid fish in Ribb Reservoir. In this study, frequency of occurrence and volumetric analysis methods were used to present the results. From a total of 203 fish samples, 132 (65%) guts contained food items. Macrophytes (29.4%), phytoplankton (27.2%), detritus (14.8%), and insects (13.6%) were the major food items in the diets volumetrically. During the dry season, L. intermedius was mainly dependent on phytoplankton (58.2%), insects (15.2%), and zooplankton (13.7%) volumetrically. Whereas, macrophytes (50.3%) and detritus (23.3%) were the dominant food items in the wet season. The frequency occurrence and volumetric contribution of the diets of L. intermedius varied significantly (χ² test, p < 0.05) between seasons. Schoener's diet overlap index revealed a slight ontogenetic dietary shift in the diets of L. intermedius. While insects, nematodes, and zooplankton were the main diets of small-sized L. intermedius, macrophytes and detritus were ingested by large-sized L. intermedius. Generally, L. intermedius fed both plant and animal-origin food items and is considered an omnivorous feeder in Ribb Reservoir.

• 현장농수산연구지
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• 제9권1호
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• pp.133-142
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• 2007

• 현장농수산연구지
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• 제17권1호
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• pp.73-84
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• 2015

Comparison of the standard and instruction for grade and quality of landscape plants between Korea and foreign countries indicates that the individual country characteristically develops and uses their own standards for landscape plants. Ultimate aim of these regulations is to develop the standard of landscape plants classified by kinds, types and purposes to improve the quality of landscape plants. This study analyzed the differences of standards and instructions for landscape plants between Korea and other countries such as Germany, Switzerland, America, Canada and Japan. Our results indicated that Korea and Japan used the diameter at 1.2m above from ground surface for the diameter at breast height(DBH) whereas Germany and Switzerland at 1.0m above from ground surface. In case of America and Canada, the standard of landscape plants included crown width, height and DBH of plants. In Germany, the standard for creeping plants and herbaceous flowers was determined by the type and the root size of plants with the standard of containers(seven to eleven types). This research would be helpful for developing the practical and environmentally suitable guideline for the grade and quality of landscape plants and also for developing the standardized distribution structures and cultivation techniques for landscape plants in Korea.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2019년도 추계학술대회
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• pp.23-23
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• 2019

• 현장농수산연구지
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• 제24권1호
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• pp.23-28
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• 2022

지네는 머리와 체절이라고 부르는 수많은 마디가 이어진 형태를 이루는 절지동물목, 지네강에 속하는 동물로, 전 세계적으로 3,000여종, 국내에는 44종(4종 7과)이 분포하는 것으로 알려져 있다. 그중 왕지네는 유효물질 탐색 및 약리활성 연구를 위한 주요 생물자원으로 인식되고 있어 향후 그 가치는 더욱 높아질 것으로 전망되고 있다. 하지만 현재까지 이에 대한 생리적·생태학적 연구는 미비하여 이에 대한 연구를 확대할 필요가 있다. 본 연구에서는 왕지네의생태학적·생리학적 특성 연구에 대한 기초 연구로 왕지네에 대한 형태적 분석을 통한 분류학적 위치를 정립하고, 암·수 구별법을 제시하였다. 이것은 향후 왕지네 인공사육을 위한 기초자료로 활용될 수 있을 것으로 기대되며, 이를 통해 왕지네 시장 확대에 기여할 수 있을 것으로 예상된다.

• 현장농수산연구지
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• 제18권1호
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• pp.37-45
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• 2016

In order to obtain the optimum application time of liquid pig manure (LPM) for growth and nutrient contents of green manure crops (GMCs), the growth and nutrient characteristics of GMCs were evaluated under different application times of LPM in pot experiment. GMCs were sown in Sept. 1, 2012. LPM was treated in soil surface at 15 days before sowing (15DBS), at 0 days after sowing (ASD) and at 25 days after sowing (25DAS). At 60 days after seeding, plant heights of barley and hairy vetch were higher in 15DBS treatment than those in other treatments. Biomass of barley was higher in the order of 15DBS (50.2g plant^-1) > ASD (49.8g plant^-1) > 25DAS (48.5g plant^-1) > control treatment (37.5g plant^-1). Biomass of hairy vetch in 15DBS treatment was higher than that in other treatments. Nutrient contents of barley and hairy vetch were not different regardless of LPM application times. On the other hand, the amounts of nutrients uptake in 15DBS treatment were higher than those in other treatments. Therefore, in considering growth status and nutrient contributions of GMC, the optimum application time of LPM was 15DBS.

• 현장농수산연구지
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• 제22권1호
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• pp.55-63
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• 2020

필터 부착에 따른 모형온실 내에서 스펙트럼은 필터에 따른 파장 폭은 넓지만 각 파장대에 따른 피크치는 나타나는 것으로 조사되었다. 각각의 모형온실 내에서 조도 및 광량자속밀도를 측정한 결과 조도는 Blue필터를 부착한 온실이, 광량자 속밀도는 Red필터를 부착한 온실이 가장 높은 것으로 나타났다. 투과율을 조사한 결과 필터를 부착한 온실이 대조구에 대비하여 약 30~40% 낮은 것으로 조사되었다. 적축면상추의 생육기간별 생체중과 건물중을 측정한 결과 대조구온실에서 정식 30일 후에 약 148g으로 가장 높았고, 다음으로 Red필터 부착온실에서 약 143g으로 높았다. 재배기간에 따른 광합성속도는 상추가 성장할수록 낮아지는 경향이었으나, Blue필터 온실은 높아지는 것으로 나타났다. 수분이용효율은 큰 차이는 없었으나 Green영역에서 높은 것으로 조사되었고, 기공전도도는 대조군 온실이 가장 높은 것으로 조사되었다. 안토시아닌 함량은 모든 시험구에서 생육 후기로 갈수록 크게 감소하는 경향이었다.

• 현장농수산연구지
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• 제20권1호
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• pp.49-54
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• 2018

느티만가닥버섯 해송이 품종의 우수 균주를 선발하기 위하여 각기 다른 자실체에서 분리한 균을 Di-mono 교배하여 균을 선발하였다. 교배한 균주를 PDA에서의 균사생장 조사를 통하여 균사생장이 좋은 3균주를 선발하였다. PDA배지에서 10일간 배양했을 때 균사생장은 3번 균주가 62mm로 가장 빠르고, 7번 균주가 58mm, 그리고 2번, 10번, 9번순이었다. 선발된 3균주, 즉, KNCAF-H-3, KNCAF-H-7, KNCAF-H-2는 톱밥배지에서 10일간 배양한 결과 각각 79mm, 76mm, 73mm의 균사생장을 보여, 대조 품종인 그린피스 5호의 55mm보다 균사생장이 좋았다.

• 현장농수산연구지
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• 제17권1호
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• pp.93-100
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• 2015

여름철 토마토 시설 재비시 CO₂ 시용에 의한 고온적응성 향상을 구명하고 그 가능성을 검토하고자 실시하였다. CO₂ 처리 농도를 달리한 온실들(무처리, 500ppm, 1,000ppm)의 기온환경은 유사하였으며, 최고기온은 약 44℃ 수준이었다. CO₂ 농도에 따른 VPD와 엽기온차에 의한 CWSI(Crop water stress index)변화를 보면 1000ppm처리가 무처리, 500ppm처리보다 수분장해를 받지 않았으며, 수분장해 정도는 1000ppm<500ppm<무처리 순으로 무처리가 수분장해 수준이 가장 높았다.

• Journal of Ecology and Environment
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• 제38권3호
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• pp.293-305
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• 2015

In order to understand the mechanisms of conversion between different algal dominance, an experiment was performed in a greenhouse from 22 June to 10 July 2011. The experiment included a treatment group subjected to three instances of nutrient enrichment and a control with no nutrient enrichment. The initial water was dominated by Ankistrodesmus of Chlorophyta. The average water temperature at 08:30 h and 14:00 h during the experiment was $31.6^{\circ}C$ and $34.6^{\circ}C$, respectively. The results showed that the total nitrogen (TN), total phosphorus (TP), dissolved total nitrogen (DTN), dissolved total phosphorus (DTP), and soluble reactive phosphorus (SRP) concentrations in the treatment were significantly higher than in the control (P < 0.05). However, the TN/TP and DTN/DTP in the control was higher than in the treatment (P < 0.05). The dominant algae in the control did not change during the experiment, while the dominant algae in the treatment switched to Planktothrix of Cyanophyta on day 9. The chlorophyll a (Chl-a), wet weight of all algae, wet weight of Cyanophyta, and percentage of Cyanophyta in the control were all significantly lower than in the treatment (P < 0.05). Amounts of zooplankton, especially rotifers, were present at the end of the experimental period. The density of rotifers between the control and treatment was not significantly different (P > 0.05), while the copepod density in the treatment was higher than in the control (P < 0.05). We conclude that green algae dominance quickly switches to cyanobacteria dominance after nutrient enrichment in a greenhouse with elevated temperature.