• Journal of Plant Biology
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• v.18 no.3
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• pp.122-128
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• 1975

With the cultivated mulberry plant which feeds silkworm on its leaves in sericulture, the measuring methods of biomass of terrestrial organs were compared and the annual net productivity was estimated. The measurement of the standing crops by means of allometric method on basis of relation between the parameter D230H, square of the diameter of the branch on 30cm high above ground($D{\frac}{2}{30}$) multiplied by its height(H), and the amount of leaves(WL) or of branch (Ws) was more accurate than other methods on basis of correlation between a character of the branch such as H, D30 or D230 and WL or Ws. The estimate of value of the net productivity of terrestrial parts of mulberry was 9.06-12.54 ton/ha.year, which was similar to that obtained from secondary forests in cool temperate zone.

• ALGAE
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• v.19 no.2
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• pp.115-122
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• 2004

The epilithic algal communities on the artificial substrata (unglazed ceramic tiles) were investigated from 5th July to 24th July 1999 with two or three days intervals for elucidating the effects of the experimental acidification. They were harvested inside the mesocosm with and without the acid treatment on Togyo reservoir within the Civilian Passage Restriction Line near Demilitarized Zone (DMZ) in Korea. After the colonization of epilithic algal community, their standing crops revealed different patterns outside and inside the mesocosm. However the time lapse of 5 days was observed on the inside with acid treatment. The dominant species were different: Achnanthes minutissima was outside but Coenochloris polycocca was inside and inside with acid treatment. The differences in floral composition were also found. Achnanthes minutissima which has been the most important species in the colonization by the epilithic algal community of the mesocosm was less important at the lower pH. Coenochloris polycocca is a species well adapted to low pH.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.177-186
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• 1995

The seasonal changes and composition of phytoplankton of the Choonsan reservior were studied from November 1990 to October 1991. 195 taxa which belong to 65 genera, 150 species, 40 varieties and 1 forms were identified. Species number during summer monthes was higher than that of other seasons. Standing crops of phytoplankton were varied from $7.8\times10^5$ cells/l to $2.2\timesl0^6$ cells/$\ell$. The dominant species were Cryptomonas erose and Trachelomonas volvoina. Chlorophyll a contents of phytoplankton was varied from $1.36\mu\textrm{g}/\ell$ to $127.46\mu\textrm{g}/\ell$. The biotic indices of phytoplankton were very similar among three sites. Saprobien-system by index of species diversity suggests that the Choonsan reservior belongs to the oligosaprophic.

• Plant Resources
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• v.1 no.1
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• pp.38-42
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• 1998

One of the most attractive short-term possibilities for increasing freezing tolerance of winter crops may be the application of chemicals. This research was conducted to determine the effect of two plant growth regulators. Terpal-C and Cerone on freezing tolerance and winter survival of canola. Three cultivars were planted on the michigan state University Agronimy Farm at East Lansing. MI. on Sept. 10. 1992 and 1993 Chemicals were applied to one-month-old plants when they reached the 5 leaf stage. Ion leakage tests for freezing tolerance were conducted before and after chemical treatment. Winter survival was evaluated by counting the plant standing in the fall and spring. Neither of the chemicals. Terpal-C. inhibited natural cold hardening.

• Journal of Plant Biology
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• v.16 no.3_4
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• pp.1-6
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• 1973

The distribution of plant communities along the Bukhan Riverside in Chun-seong was studied by means of the methods fo Curtis and Pattern. The communities were arranged in a single-dimensioned ordination on the basis of the importance values of the persistent species. Leading dominant species, form the 'low' level to the 'high' levels of the ordination gradient, were Phalaris arundinacea, Salix gilgiana, Artemisia feddei, Zoysia japonica, Pennisetum japonicum, and Arundinella hirta. These species from a continuum from the river to the dry grassland depending upon available soil-moisture. Standing crops in terms of dry weight and the nitrogen content of the above-ground parts of these species showed a good relationship with gradients of available soil-moisture.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.29-36
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• 1994

We studied on the mineral nutrients and productivity of grasslands in Kimhwa. The vascular flora of grasslands in Sakok-ri, Wasoo-ri, and Yukdan-ri located at Kimhwa were composed of 39, 28, and 32 species respectively. The most important species were Arundinella hirta and Miscanthus sinensis These two species contributed greatly to the standing crops of live material which was in excess of $146.47g/m^2$ throughout the growing season. The daily production throughout the growing season was in excess of $1.04 g/m^2$. Factors which affected the daily productivity of grasslands in Kimhwa were phosphours and water content.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.103-107
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• 2003

Spatial distribution of phytoplankton was investigated in the southwestern sea of Korea in May 2000 in terms of phytohydrography. The sampling was done at the 0m, 30m, 50m of 15 selected stations, and permanent slides of each samples were prepared by QPS method for quantitative and qualitative analyses. Phytoplankton standing crops ranged from 3.23${\times}$10$\^$-4/ to 1.09${\times}$10$\^$-7/ cellsㆍ$\ell$$\^$-1/ in the study area. Dominant species comprised of 9 diatoms and 2 phytoflagellates, showing higher dominance of diatom and most predominance of Skeletonema costatum in all layers of most stations. Phytohydrographic results indicate that the study area might be divided into 4 categories, that is, I area is designated as neritic area where occurrence of terrestrial and coastal species is frequent, II area as intermediate area, III area as offshore area where oceanic species dominate, and IV area as other's. Especially in the II area, Skeletonema costatum was most predominant at both surface and 30m layer in most stations and represent an characteristic of northward expansion with spring massive bloom.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.481-492
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• 1999

The observations on the spatio-temporal distribution and seasonal fluctuations of phytoplankton community were carried out in Deukryang Bay of the Korean Southwestern Sea from June 1992 to April 1993. A total of 75 species of phytoplankton belonged to 47 genera was identified. In Deukryang Bay seasonal succession in dominant species; P. alata, G. flaccida, S. costatum, L. danicus and N. longissima in summer, St. palmeriana, Ch. curvisetus and B. paxillifera in autunm, S. costatum, Ch. curvisetus, E. zodiacus and Pn. pungens in winter, and As. glacialis, As. kariana, N. pelagica, Th. nitzschioides and S. costatum in spring, were very marked, that is to say, the communities structure of phytoplankton in Deukryang Bay appeared to be various species composition and it was occupied with diatoms all the year round. Phytoplankton standing crops fluctuated with an annual mean of $1.4{\times}10^5 cells/1 between the lowest value of 2.6{\times}10^3 cells/1 in July and the highest value of 1.0{\times}10^6 cells/1$ by S. costatum in January. Densities of the phytoplankton cell number by the samples of Deukryang Bay ranged from $2.6{\times}10^3cells/1 to 1.2{\times}10^5 cells/1 with the mean value of 3.6{\times}10^4cells/1 in summer, from 6.0{\times}10^3cells/1 to 2.6{\times}10^5 cells/1 with mean of 1.5{\times}10^5 cells/1 in autumn, from 1.3{\times}10^4cells/1 to 1.0{\times}10^6 cells/1 with mean 3.5{times}10^5 cells/1 in winter, and from 4.8{\times}10^3cells/1 to 6.0{\times}10^5 cells/1 with mean of 1.6{\times}10^5 cells/1$ in autumn. That is to say, phytoplankton standing crops was large in low temperature seasons, on the other hand small in high temperature seasons. Chlorophyll $\alpha$ concentration fluctuated between 0.l9 $\mu$g/l and 12.3 $\mu$g/l in March. in Deukryang Bay seasonal flucturation in chi-$\alpha$ concentration was not marked. Especially, chl-$\alpha$ concentration in the water around Deukryang Island located in the middle part of Deukryang Bay showed patchy distributions with a very high concentration. And chl-$\alpha$ concentration was high during a year. Therefore, phytoplankton production in Deukryang Bay could be very high year-round.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.45-55
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• 1998

Phytoplankton community and primary productivity have been investigated in a fall season in the southern coastal waters of the last Sea, Korea. A strong thermocline formed at the 20\~60\;m$ layer and a cold water mass also existed in the bottom around Yong-il Bay. The offshore of the surveyed area was likely to be influenced by relatively warmer water, whereas the inshore represented Higher primary productivity with lower water temperature and lower salinity. A total of 133 species of phytoplankton occurred, representing 107 spp. of diatom, 23 spp. of dinoflagellate 3 spp. of silicoflagellate. Skeletonema costatum and Asterionellepsis glacialis were most predominant with more than $30\%$ dominance ratio, while Leptocylindrus danicus was also dominant at all transect lines. Standing crops of phytoplankton ranged from $2.7{\times}10^3\;to\;141.6{\times}10^3\;cell^{\ell-1}$. Chlorophyll a concentration varied with stations and layers, but the $30\~50$ m layer showed maximun with about $1.18{\mu}g{\ell}^{-1}$ rather than at the surface layer. It is believed that the maximun in standing crops and chlorophyll of phytoplankton formed at the $20\~50$ m layer above the thermocline during the survey. Phytoplankton primary productivity ranged from 0.32 to 3.04 mgC $m^{-3}\;hr^{-1}$, showing higher at the inshore than at the offshore. The range of integrated primary productivity was $263.3\~1085.5 mgC\;m^{-2}\;day^{-1}$ for the euphotic layer. Photosysthesis rates varied with the range from 0.76 to 8.04 mgC mgChl $\alpha^{-1}\;hr^{-1}$. Phytoplankton photosynthesis at the inshore was saturated at lower irradiance ($15\~35\%$ of surface) and showed higher efficiency, Thus, it revealed that the phytoplankton community probably adapted to the middle of euphotic layer because the depth of mixing layer became thinner due to the formation of thermocline.

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.8-17
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• 2003

The spatio-temporal distribution and seasonal fluctuations of phytoplankton community were carried out in the Southwestern parts of Deukryang Bay of the Korean South Sea from July 1997 to January 1998. A total of 60 species of phytoplankton belonging to 41 genera was identified. In the southwestern parts of Deukryang Bay seasonal succession in dominant species; Eucampia zodiacus, and Chaetoceros spp. in summer, Nitzschia longissima, Chaetoceros curvisetus and Bacillaria paxillifera in autumn, Skeletonema costatum and B. paxillifera in winter, were very predominant. The community structure of phytoplankton in the southwestern parts of Deukryang Bay appeared to be diverse in species composition, and diatoms were most dominant through the year. Phytoplankton standing crops fluctuated with an annual mean of $1.2{\times}10^5$ cells $L^{-1}$ between the lowest value of $8.0{\times}10^3$ cells $L^{-1}$ in January and the highest value of $6.9{\times}10^5$cells $L^{-1}$ by Nitzschia longissima in January. Densities of the phytoplankton cell number by the samples of the southwestern parts of Deukryang Bay ranged from $1.1{\times}10^4$ cells $L^{-1}$ to $1.3{\times}10^5$ cells $L^{-1}$ with the mean value of $4.1{\times}10^4$ cells $L^{-1}$ in summer, from $1.0{\times}10^4$ cells $L^{-1}$ to $6.9{\times}10^5$ cells $L^{-1}$ with mean of $1.8{\times}10^5$ cells $L^{-1}$ in autumn, from $8.0{\times}10^3$ cells $L^{-1}$ to $4.6{\times}10^5$ cells $L^{-1}$ with mean $1.6{\times}10^5$ cells $L^{-1}$ in winter. That is to say, phytoplankton standing crops was high in low temperature seasons, while low in high temperature seasons. Chlorophyll a concentration fluctuated between 1.08 mg $m^{-3}$ and 21.6 mg $m^{-3}$ in January. In the southwestern parts of Deukryang Bay temporal change in chl-a concentration was not apparent. But chl-a concentration was high during a year. Therefore, phytoplankton production in the southwestern parts of Deukryang Bay could be very high year-round.