• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.31-37
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• 2010

It was investigated that morphological characteristics of leaf and stomata, chlorophyll contents and wood anatomy characteristics in Schisandra chinensis, Schisandra nigra and Kadsura japonica. Leaf morphological characteristics were significant at 5% levels within the species and within the individuals as a male, a female and monoecious. K. japonica was the longest in the leaf length, followed by S. chinensis and S. nigra. For the leaf length among S. nigra individuals, the female was longer than male and monoecious. As for the Petiole length, S. nigra was twice longer than S. chinensis and K. japonica. Stomata length was ranged from $92.5\;{\mu}m$ to $105.9\;{\mu}m$ for S. nigra, $79.9\;{\mu}m$ for S. chinensis, $76.2\;{\mu}m$ for K. japonica. S. nigra was longer than the others in length and width, while its stomata density was lower than the others. The size of vessel elements and xylem fiber showed a similar tendency to stomata, significant at 5% levels within S. nigra individuals (male, female and monoecious). Chlorophyll contents were also variable in inter and intra species and in general K. japonica showed higher levels of chlorophyll contents than Schisandra spp. plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.386-391
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• 1987

Effect of growth light intensity (5% and 20%) and planting density (40, 56, 90/33㎡) on yield and red ginseng quality was investigated in a sandy loam field of ginseng plantation. High growth light intensity had no effect on yield and quality but decreased stem length, leaf area and chlorophyll content and increased specific leaf weight. The optimum planting density was 64/3.3㎡ for both yield and Heaven + Earth grade (HE grade) of red ginseng. HE-shape ginseng rate showed significant positive correlation (P=0.0l) with HE grade rate.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.257-264
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• 2006

In order to evaluate the application of Algae Online Analyzer (AOA), an instrument of automatic measurement of chlorophyll a concentration, was tested and compared with the acetone extraction method on the basis of microscopic counting of phytoplankton in field water (Paltang Reservoir). We simultaneously conducted AOA operation and extraction method with the same water sample, to compare both results of chlorophyll a measurement. Phytoplankton were enumerated by inverted microscope with the Sedgwick-Rafter chamber, and classified into the genus or species. According to the AOA measurement, the diatom most (83.6%) strongly contributed to the total chlorophyll a concentration, followed by chlorophyceae> cyanophyceae>cryptophyceae. Overall, the results of both AOA and extraction method showed a similar trend and significant correlation (r=0.87, n=302, p<0.001), however, there were some differences according to the season and species. In particular, the relationship between AOA Chl-a density of the diatom (r=0.73, p=0.010) and cyrptophyceae (.=0.83, p=0.00154) were siginificant, while chlorophyceae (r= -0.13) and cyanophyceae (r= -0.16) showed no clear relationship during the study period. Although we can not fully understand why there was difference between both mothods, AOA application for alarming algal bloom and water quality management during the algal bloom appears to be very relevant. However, the further study or technical upgrade of AOA measurement is required, especially in the case of low density of phytoplankton or species-specific measurement.

• KSBB Journal
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• v.26 no.3
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• pp.206-210
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• 2011

The growth effect of Nannochloropsis oculata (N.oculata), unicellular microalgae, by alginate was investigated. Alginate was depolymerized with sulfuric acid ($H_2SO_4$) and heat ($121^{\circ}C$), simultaneously. Addition of 0.75% alginate oligomer depolymerized with 0.2 N $H_2SO_4$ showed the maximum yield and the growth rate of N. oculata. Chlorophyll content and reducing sugar was increased by alginate oligomer in a dose-dependent manner. Alginate oligomer promoted the growth of N. oculata, whereas the original alginate polysaccharides had no significant effect. Laminaria japonica (L. japonica) extract containing high level of alginate was also increased growth rate and chlorophyll content. $CO_2$ supply addition to L. japonica extract showed no change the growth rate, although addition to alginate oligomer showed prominently increased. N. oculata could use more saccharides in presence of $CO_2$ according to reducing sugar determination. From these results, it is useful to establish optimal condition for high cell density cultivation of N. oculata.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.3
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• pp.286-292
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• 2006

Chlamydomonas reinhardtii is a green algae that can use light energy and water to produce hydrogen under anaerobic condition. This work reports the effect of limiting factors on hydrogen production in sulfur deprived anaerobic C. reinhardtii culture. In order to confirm the relationship between hydrogen production and limiting factors such as residual PSII activity and endogenic substrate degradation, the increase in chlorophyll concentration and the decrease in starch concentration was investigated during sulfur deprivation. The overall hydrogen production increased depending on cell density in range of $0.4{\sim}0.96\;g$ DCW/l. At this time, the increase in chlorophyll concentration during 24 h after sulfur deprivation increased in proportion to hydrogen production, however, the decrease in starch concentration was not proportional to that. Therefore, hydrogen production under sulfur deprivation using green alga was closely associated with the residual PSII activity than the endogenic substrate degradation.

• Journal of Korean Society on Water Environment
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• v.26 no.1
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• pp.148-155
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• 2010

Water quality and plankton community dynamics after the introduction of two domestic freshwater shellfishes (Unio douglasiae Griffith & Pidgeon and Cipangoplaudina chinese malleata Reeve), were monitored daily in enclosures, which constructed in the tidal zone of eutrophic agricultural reservoir (Shingu reservoir, Korea) for one week between July 31 and August 6, 2007. This biomanipulation study to improve the water quality of eutrophic lake, comprised eight enclosures (duplicate x four kinds), enclosure had no mussels (Control), stocked only with U. douglasiae at density of 60 individuals (UD), stocked only with C. chinese malleata at density of 60 individuals (CCM), and combined-stocked with 30 individuals of UD and 30 individuals of CCM (MIX), respectively. Our results clearly indicate that UD strongly decreased the concentration of chlorophyll-a and increased the water transparency, whereas CCM and MIX (included CCM) did increase algal density or decrease transparency, due perhaps to the disturbance of C. chinese malleata. Therefore, the field application of shellfish to enhance the water quality of eutrophic agricultural reservoir, should consider the grazing characteristics of biological control agents, especially active moving animals like snail.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.94-99
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• 2011

This study was performed to investigate the effect of foliar feeding as the fertilization on creeping benrgrass green. Research results have showed that the visual quality of bentgrass as well as shoot density and chlorophyll index dramatically improved after foliar feeding. Shoot density of bent grass in foliar based fertilization was 2.8 ea/$cm^2$ higher than that of the liquid based fertilization during the experiment period, moreover that the foliar feeding is more effective to alleviate shoot density during the rainy season in summer. Results showed that foliar feeding was key role to achieve the stable visual quality, chlorophyll index and maintained Normalized Difference Vegetation Index (NDVI) throughout the year in addition to get fast recovery after aeration and dry spot. These were consistent with the previous research of foliar feeding which directly provided nutrient to the turfgrass leaf thus increased turfgrass growth within a short time. It is projected to be a especially adequate management program during the hot summer season in which the nutrition feeding is low. However, root growth was no significant difference between foliar based fertilization and liquid based fertilization. Golf Course managers also should consider about the number of frequent fertilizing. Lastly, it was no big change in chemical property by soil foliar based fertilization which is meaning of preventing the soil salinization, meanwhile, it is prone to reach the nutrient deficiency. It hopes to be settled as the general fertilization in golf course of Korea, since there are many advantages of foliar based fertilization program. It is suggested to study more practical process of foliar feeding through the further research.

• Korean Journal of Ecology and Environment
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• v.33 no.2 s.90
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• pp.136-144
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• 2000

M. aeruginosa isolated from Lake Paldang was cultured in CB medium, and then each wet plants put into the cultured medium at a rate of 0.5 g and 2.5 g wet wt/l. There was slight inhibition by the input of cattail and iris of each 0.5 g wet wt/l cultured medium, but showed no reduction in algal growth in other flasks. Among the applied plants, ginkgo, pine needles, big cone pine, waterreed and water chestnut had an effect on inhibition of algal growth at the input of 2.5 g wet wt/l. Plants which were dried for 3 days at $50^{\circ}C$ introduced into the testing flask for 10days cultured at dose rates of 2.5 g/l. When chlorophyll a concentration was remarkably high as $802.6\;{\mu}g/l$ after five days, there was noticeably less chlorophyll compared with control at a rate of 98% by big cone pine, 96% by ginkgo, 95% by pine needles and 86% by rice straw, respectively. To examine the effect of plant extracts on algal growth, big cone pine and water chestnut were put to the amount of 1.25 g liquid extracts/l. Chlorophyll a concentration and cell density decreased to the extent of average 43% as compared with the beginning of experiment, but when concentration of chlorophyll a increased a most high, the inhibition of algal growth by liquid extracts did not affect at all. When a quantity of plant equivalent to 2.5 g liquid extracts/l inhibited the growth of algae by 95% after nine days.

• Journal of Aquaculture
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• v.13 no.4
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• pp.339-351
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• 2000

Optimal environmental conditions, that sustained fastest growth, lowest mortality and abnormality of the scallop Patinopecten yessoensis, were identified from field experiments undertaken at Chumunjin during 1991-1998. Temperature within the water column 10~30 m depth ranged between 5 and 23$^{\circ}C$; high temperature and daily fluctuation resulted in growth retardation and heavy mortality of the scallop. Optimal salinity range was between 31.5 and 34.5%0 and water transparency 6.0 and 18.1 m, which was significantly affected by phytoplankton density. Chlorophyll concentration ranged between 0.04 and 3.51 f.lgfL. Low temperature and high chlorophyll concentration appear to support faster growth of the scallop. Optimal periods of transplantation for intermediate culture were between mid July and early November: cultured under high density during July-August as a first step and under low density during mid September through early November as a second step. Optimal stocking density in square net cage (<35${\times}$35 em) for intermediate culture was 30-40 individuals per cage for main culture using lantern net and 80 -100 individuals of the size of 1.5 ~ 3.0 em shell height per cage for sowing culture. During the intermediate culture, the highest growth was realized, when the cage was held at water depth between 10 and 15 m. Water depth below 25 m, however, was best to avoid mass mortality during the periods of abnormally high water temperature and high variation of water temperature. The daily growth rate during the intermediate culture was between 0.019~0.381 mm; low in January and February but high in March and April. It is suggested that the main culture is commenced before June under low stocking density to avoid the possibility of mass mortality during summer by high water temperature.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1024-1030
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• 2001

The key factors for high-density Haematococcus pluvialis cultures and conditions for astaxanthin induction were examined to maximize astaxanthin production. Light intensity was found to be the most important factor, and thus experiments were found to be the most important factor, and thus experiments were carried out using different light sources and intensities. A high cell density of over 2.7 g/l was obtained at $75{\mu}E/m^2/s$, whereas a much lower cell concentration (<1.0 g/ 1) was obtained with lower light intensities $(15-30{\mu}E/m^2/s$. A high light intensity and the supplement of 470 nm photons had a more dramatic effect on the final astaxanthin concentration and per cell astaxanthin content. A maximum astaxanthin concentration of 6.5 mg/l was obtained at a light intensity of $160{\mu}E/m^2/s$, whereas only 1.3 and 0.7 mg/l were obtained at 30 and $15{\mu}E/m^2/s$, respectively. A supplement of 470 nm photons enhanced the carotenoid and chlorophyll formation.