• 한국물환경학회지
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• 제26권4호
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• pp.673-680
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• 2010

Environmental factors and phytoplankton community in Lake Doam were monthly investigated at 3 stations from April 2009 to November 2009. During the study period, the concentrated rainfalls occurred at between July and August and then the TP and turbidity were sharply increased in in-lake. A total of 91 phytoplankton species was classified and these were consisted of 38 Bacillariophyceae, 35 Chlorophyceae, 10 Cyanophyceae, and 8 other species. Bacillariophyceae and Chlorophyceae were dominated during the seasonal succession of phytoplankton community, especially summer season. Bacillariophyceae was dominated from spring season to summer season and Chlorophyceae was dominated at summer season and autumn season. However, the dominance of Cyanophyceae generally developed at summer season in eutrophic water was not observed. From the analysis of correlation coefficient between environmental factors and phytoplankton cell number, we confirmed that there was a negative correlation between turbidity and cyanobacteria cell number (P<0.01). This result indicated that turbid water acts as the inhibitor of the cyanobacteria growth than other phytoplankton community.

• 한국자원식물학회지
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• 제25권6호
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• pp.700-706
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• 2012

Influences of different seeding dates on growth, seed yield, fatty acid composition and oil content were investigated in flax plants for two years. The results indicated that plant height in early seeding date was higher than that of delayed seeding dates during first season. Furthermore, seeding date also significantly affected the ripened seed rate and the rate increased with the delay in seeding date in first season. Seed yield in the first crop season was significantly higher than the second crop season. Palmitic acid showed variation in different seeding dates. Contrarily, stearic acid was stable and did not changed by different seeding dates. Linolenic acid was found in highest amount in all seeding dates consecutively in two cropping years. Highest oil content was recovered from the seeds of flax sown at 29 Apr. and May 9 in first and second cropping year respectively.

• Ocean and Polar Research
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• 제44권2호
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• pp.127-137
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• 2022

This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m²/yr, and the highest production was 519 gDWt/m²/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m²/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

• 아시안잔디학회지
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• 제22권1호
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• pp.25-34
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• 2008

본 연구는 잔디종자에 감마선을 조사하였을 때 종자 발아율 및 초기 생육을 관찰하여 잔디 종류에 따른 방사선 감수성을 관찰하고 돌연변이 유기를 위한 적정 방사선 선량을 결정하고자 수행되었다. 난지형 잔디인 zoysiagrass, bermudagrass, seashore paspalum과 한지형 잔디인 Kentucky bluegrass, tall fescue, perennial ryegrass, creeping bentgrass를 실험에 사용하였다. 다양한 방사선 선량으로 24시간 처리한 후 발아율 및 신초, 뿌리 길이와 생체중을 조사한 결과 방사선 선량이 증가할수록 발아율 및 초기 생육이 감소하는 것으로 나타났다. 감마선에 의해 생육이 50% 억제되는 반치사선량을 조사한 결과 잔디 종류에 따라 다양하게 관찰됨을 알 수 있었다. 잔디 종류별 반치사선량 ($LD_{50}$)은 zoysiagrass, seashore paspalum, bermudagrass, Kentucky bluegrass, perennial ryegrass, tall fescue, creeping bentgrass 각각 300, 150, 600, 150, 200, 100, 200 Gy로 bermudagrass가 가장 높고, tall fescue가 가장 낮게 나타났다.

• 한국작물학회지
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• 제45권3호
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• pp.216-219
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• 2000

고지로 개발된 멀칭종이, 여기에 폐식용유를 먹인 밀칭종이 및 요소를 피복한 멀칭종이의 봄감자 멀칭재배에서 잡초발생, 토양온도와 감자의 생육 및 수량 변화를 조사한 결과를 요약하면 다음과 같다. 1 감자 파종 직후 약 10일간의 평균지온(5cm)은 일반 멀칭종이에서 18.9$^{\circ}C$로 무멀칭처리보다 0.5$^{\circ}C$ 낮았고, 기름먹인 멀칭종이의 지온은 20.6$^{\circ}C$로 무멀칭처리보다 1.2$^{\circ}C$높았다. 한편, 밝은 날 최고기온은 무멀칭에 비하여 기름먹인 멀칭종이의 경우는 6.6$^{\circ}C$ 높아졌으며 일반 멀칭종이는 무멀칭에 비하여 4.6$^{\circ}C$ 낮아졌다. 2. 멀칭 후 80일까지 일반 멀칭종이는 약 20% 정도만 분해되었고, 비료를 피복한 멀칭종이의 분해는 이보다 빨랐지만 멀칭 후 80일까지 약 50%정도가 분해되었다. 기름백인 멀종이는 일반 멀칭종이에 비하여 분해가 다소 지연되었다. 모든 멀칭종이 처리에서 감자 전 생육기간에 걸쳐서 잡초의 발생이 효과적으로 억제되었다. 3. 감자의 출아율은 처리간 유의한 차이는 없었으나 기름먹인 종이에서 다른 처리에 비해 다소 낮았으며, 감자의 지상부 및 뿌리건물중도 기름먹인 종이에서 다른 처리에 비해 낮았다. 감자의 수량은 기름먹인 멀칭종이가 다른 처리에 비해 유의하게 낮았으며. 일반 멀칭종이, 요소피복 멀칭종이 및 무멀칭 처리간에는 감자 수량에 유의한 차이가 없었다. 4. 기름먹인 멀칭종이는 출아기 및 생육초기 고온으로 씨감자의 부패가 많았으며 초기생육도 억제되어 수량이 낮았다. 그러나 본 실험(4월15일 파종)에서보다 조기에 파종하는 경우는 본 연구결과와 다를 것으로 생각되며 이에 대해서는 추가적인 검토가 필요하다.

• 한국환경복원기술학회지
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• 제12권5호
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• pp.1-12
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• 2009

This research was initiated to investigate the revegetation characteristics under the seeding amount treatments of cool-season turfgrasses on the disturbed slope. 4 different seeding amounts of cool-season turfgrasses (0.0 $g/m^2$, 1.5 $g/m^2$, 3.0 $g/m^2$, 6.0 $g/m^2$) with the same seeding amounts of native woody (Rhus chinensis, Albizzia julibrissin) and herbaceous plants (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena) were treated with 3 replications on the experimental disturbed slope. Data such as soil hardness (mm), moisture content (%), surface coverage rate (%), the number of each germinating plant and plant height were analyzed. There were no statistic differences observed in the soil hardness and the soil moisture content while a significant difference was observed in the surface coverage rates. The surface coverage rates were higher in 3.0 $g/m^2$ and 6.0 $g/m^2$ plots compared to the rest two plots of cool-season turfgrasses. However, the emergence of native woody and herbaceous plants was relatively low in 3.0 $g/m^2$ and 6.0 $g/m^2$ plots of high seeding amounts of cool-season turfgrasses. This result indicated that high seeding amounts of cool-season turfgrasses could decrease the emergence of native woody and herbaceous plants. We concluded that 1.5 g~3.0 $g/m^2$ seeding amounts of cool-season turfgrasses was optimum level for the balanced emergence of cool-season turfgrasses, native woody and herbaceous plants in the viewpoint of the ecological disturbed slope revegetation.

• 생물환경조절학회지
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• 제8권2호
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• pp.83-89
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• 1999

여름철 고온기에 반결구상추를 식물공장에서 재배할 때 자주 발생하는 잎끝마름증 현상을 경감시키고, 생산성을 향상시키기 위해 품종, 육묘배지, 베드 기울기, 베드위치, 급액량과 같은 최적의 재배조건을 구명하기 위하여 실험을 수행하였다. Rex와 Flandria 품종은 다른 품종에 비해 비록 생육은 약간 저조했으나 상품성이 높고, 잎끝마름증 발생율이 적어 여름철 고온기에 적합한 품종인 것으로 나타났다. 육묘배지는 물리, 화학적 특성이 우수한 코코피트에서 상추의 생육량이 높았으며, 근권부에 배양액의 흐름을 원활하게 해 줄 수 있는 베드의 기울기는 l~2%가 적당하였다. 급액량은 반결구상추 생육에서 베드당 2$\ell$가 적합하였다 베드설치 높이에 따른 반결구상추 생육은 베드의 높이가 낮을 때가 높을 때보다 좋았다. 이것은 베드높이를 낮게 설치함으로써 작물주변의 온도와 습도분포가 결구상추의 생육에 적합하였기 때문인 것으로 생각되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1390-1393
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• 2006

Data spread over 11 years (1986-1996) pertaining to a synthetic population developed by inter se mating of half-breds of Corriedale and Russian Merino with Nali maintained at CCS Haryana Agricultural University, Hisar were utilized for the estimation of genetic parameters for growth traits. The means for birth weight (BWT), weaning weight (WWT), six month body weight (SWT), yearling weight (YWT), preweaning daily gain (PRW) and post weaning daily gain (POW) were 3.35 kg, 10.79 kg, 13.28 kg, 18.96 kg, 82.6 gm and 27.6 gm, respectively. The effects of year and season of birth and sex of lamb were significant for all the traits under study except the effect of season of birth for WWT, SWT and PRW. No definite trend was observed over the years for the averages of body weight and gain. Lambs born during the spring season performed better for BWT, WWT and PRW while the performance of lambs born during autumn was better for the other traits included in the study. The male lambs were heavier than the females for body weight at all stages and gain in weight. The heritability estimates for WWT and PRW were low; for BWT and SWT were moderate and for YWT and POW were high. Birth weight had high heritability and high genetic correlations with subsequent body weights and gains but due to the presence of a maternal effect on BWT and WWT, a sequential selection procedure is recommended for the improvement of growth rate in sheep.

• 수산해양교육연구
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• 제27권3호
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• pp.718-724
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• 2015

To survey the most feeding frequence of formulated diet as food for cultured puffer in winter season, we performed a rearing test using juveniles of river puffer, Takifugu obscurus (body weight 15.0 g) for 120 days. The feeding frequencies were set up as 2times/1day, 2times/2days, 2times/3days and 2times/4days. We tested triplicately the experiment and investigated survival rate, daily food intake (DFI), feed efficiency (FE), condition factor (CF), daily growth rate (DGR). Consequently, growth was increased following to an increasing of feeding frequency, was the fast in 2times/1day of feeding frequency, and was the slowest in 2times/4days (p<0.05). DFI and CF were increased following to an decreasing of feeding frequency and was the highest in 2times/4days of feeding frequency. FE was decreased following to an decreasing of feeding frequency, and was the highest in 2times/1day of feeding frequency. In a proximate carcass composition at the final day, moisture and crude lipid contents were the lowest in 2times/4days, and in survival, there was not any significant difference among experimental groups. Therefore, we concluded that the 2times/2days are the best of feeding frequency for economical benefit of river puffer culture in winter season.

• 한국조경학회지
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• 제14권1호
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• pp.1-13
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• 1986

The purpose of this study is to investigate the effect of temperature control by a shade tree and the lawn area. In this investigation, we find out that artificial-lawn, concerte, and exposed soil are more higher temperature than covered with plant materials. The results of the measurement may to summerized as follows; 1) Low-temperature effects of zoysia japonica is more controlled by condition of growth than leaf length of grass. Surface temperature make 0.7$^{\circ}C$ difference between long grass (15cm), and short grass (5cm), but make 5$^{\circ}C$ difference between good growth grass (230/10$\textrm{cm}^2$) and bad growth grass (80/10$\textrm{cm}^2$). 2) The surface temperature of the lawn area is 40.5$^{\circ}C$ lower on a maxinum than that of the artificial lawn (July 28, 1985). During the day of summer, shade area under the shade tree is 0.9$^{\circ}C$ lower then lawn area surface temperature, 6.9$^{\circ}C$ lower than bad growth lawn, 10.3$^{\circ}C$ lower than exposed soil, and 18$^{\circ}C$ lower than concrete surface temperature. 3) Natural irrigation effect on the surface temperature fluctuation. But this effect is changed by compositions of ground materials and time-lapse. 4) Sunny day is more effective than cloud day. 5) In summer season, surface temperature make a difference compare to temperature of 0.5-1.5m height from ground : Surface temperature is 3.4$^{\circ}C$ lower at the lawn area (11 a.m.), 4.2$^{\circ}C$ lower at the shade area the shade tree, 12.7$^{\circ}C$ higher at the concrete area (3p.m.), 38.8$^{\circ}C$ higher at the artificial lawn (2p.m.) 6) According to compositions of ground materials and season have specific vertical temperature distribution curve. 7) In summer season, temperature distribution of 0.5-1.5m hight at the shade tree is 4.8-5.7$^{\circ}C$ lower than concrete area (noon-3p.m.)