Chlorophyll-a and its degradation products (pheopigment) contained in the sediment were determined to evaluate the eutrophication status in the downstream of Nakdong River. The chlorophyll-a and pheopigment concentrations of sediment ranged 11-646 mg μ

오염부하량이 높은 경안천과 오염부하량이 낮은 철원북방 비무장지대내 토교저수지에서 식물플랑크톤의 크기별 현존량과 chlorophyll a농도에 대한 계절적 변화 및 환경요인과의 상호관계를 조사하였다. 또한 식물 플랑크톤의 크기를 고려하여 > 8μm, 3-8μm, <3μm 세포 크기별로 분획하여 현존량과 chl. a 농도를 관찰하였다. 물리.화학적 환경요인은 경안천이 토교저수지보다 높게 나타났다. 식물플랑크톤 현존량은 경안천에서

본 연구는 1998년 5월부터 11월까지 대청호의 2개 정점 표ㆍ중ㆍ저층에서 수질과 일차생산을 나타내는 식물플랑크톤 현존량과의 관계를 규명하기 위하여 물리ㆍ화학적 환경요인(수온, 용존산소량, pH, 투명도, 총질소, 질산염, 아질산염, 암모니아, 총인, 인산염, 용존총인, 총유기탄소, 부유물질), 식물플랑크톤 현존량, chlorophyll-a의 농도를 조사하였다. 영양염류(아질산염, 질산염, 암모니아 및 인산염)가 과거에 비하여 증가되었으며, 총질소,

시아해의 수질환경과 식물플랑크톤 생물량의 계절변동 특성 및 식물플랑크톤 생물량변동에 영향을 미치는 환경요인을 파악하기 위해 1995년 2월,4월,7월과 10월 4회에 걸쳐 계절별로 23개 관측점의 표층과 저층 해수를 대상으로 현장조사를 실시하였다. 결과, 시아해는 2월에 최저수온, 8월에 최고 수온을 나타내나, 염분은 6, 7월에 높고 겨울에 낮은 특성을 나타내었으며, 연중 빠른 유속과 조석혼합 등으로 수층 간 혼합된 양상과 매우 낮은 투명도를 나타내고

In order to investigate the properties in distribution and movement of anchovy school catches by the lift net in the Kamak bay and their relation to the environmental factors, I. e., the amount of chlorophyll-a and turbidity were observed from June to August in 1997 and compared with the catch of anchovy by the lift net. The results obtained are summarized as follows;1) The amount of chlorophyll-a ranged from 4.0 to 12.0 mg/m3 on July and from 3.0 to 15.0 mg/m3 on August in horizontal distribution, the amount of chlorophyll-a ranged from 3.0 to 8.0mg/m3 on June, from 5.5 to 11.6 mg/㎥ on July, and from 6.0 to 11.1 mg/m3 on July and from 1.0 to 6.0ppm on August, respectively. 2) Anchovy school can be presurmed, they are come from north of bay, visited and distributed through east of bay at the middle of June. Moreover, they spreaded in all bay. Then gradually, when July arrive, they go to the south the nearest the coasts, and they are outflow through the south entrance of bay at the end of August.3) The catch of anchovy was highest on July, poor second on August, and lowest on June. The chlorophyll-a and the turbidity influenced remarkably on the distribution and movement of anchovy school and the influence of chlorophyll-a was alrgest.

전형적인 도시근교 하천(潮滿江)에서 수질의 오염양상을 93년 6월부터 94년 9월까지 조사하였다. 연평균 BOD 농도는 9.3 mg O2/ l로 5급수였고, TN, TP 및 chl-a 는 각각 4.6 mg N/ l, 239 μg P/ l 및 104 μg/l로 과영양상 태였으며, alkalinity, DO, 투명도, TSS 등 다른 수질인자도 부영양화 특성이 잘 나타났다. 연평균 TN/TP의 비는 19로서 P가 조류의 생장을 제한하는 요인으로 작용 할 수 있음을 시사한다. 연평균 질소화합물 농도에서 무기질소가 66%, 유기질소는 34% 차지하였고 무기질소 중에서 암모니아가 63%, 질산염이 37%였다. 지류 중에서 해반천의 질소와 인부하량이 가장 컸으며 해반천의 NH4는 본류보다 3.5배 이상 높게, TP 농도는 본류보다 2.5배 높은 농도로 유입되었다. 생활하수가 유입되는 해 반천에서 무기질소 또는 인이 차지하는 비율이 매우 높았다. 담수조류는 여름에 남조류 Microcystis, 겨울에 규조류 Stephanodiscus가 번무하는 등 오염지표성 조류가 대발생하는 수계였다. Chl-a량은 계절에 따른 전형적인 변동을 찾아볼 수 없었고 봄∙가을보다 겨울에 현존량이 더 높았다.

This study was conducted to estimate the removal efficiency of algae by a mechanical Screw Brush Cone Filter in a lake. The device used a stainless steel cone-shaped filter with a screw brush. The ability of the developed device to remove algae larger than 20μm in Lake ChaSa, Gwangyang city was tested from August to September 2014. The results show that the removal rates for chlorophyll-a, suspended solids and volatile suspended solids were 44-87%(mean 61%), 35-54%(mean 40%), and 37-46%(mean 43%), respectively. This study also discusses equipment and device operation costs and device application problems, and suggests in situ. solutions to these problems.

The objective of this study was to find a rapid determination of the hot air stress in maize (Zea mays L.) leaves using a portable chlorophyll fluorescence imaging instrument. To assess the photosynthetic activity of maize leaves, an imaging analysis of the photochemical responses of maize was performed with chlorophyll fluorescence camera. The observed chlorophyll imaging photos were numerically transformed to the photochemical parameters on the basis of chlorophyll a fluorescence. Chlorophyll a fluorescence imaging (CFI) method showed that a rapid decrease in maximum fluorescence intensity (Fm) of leaf occurred under hot air stress. Although no change was observed in the maximum quantum yield (Fv/Fm) of the hot air stressed maize leaves, the other photochemical parameters such as maximum fluorescence intensity (Fm) and Maximum fluorescence value (Fp) were relatively lowered after hot air stress. In hot air stressed maize leaves, an increase was observed in the nonphotoquenching (NPQ) and decrease in the effective quantum yield of photochemical energy conversion in photosystem II (Φ PSII). Thus, NPQ and ΦPSII were available to be determined non-destructively in maize leaves under hot air stress. Our results clearly indicated that the hot air could be a source of stress in maize leaves. Thus, the CFI analysis along with its related parameters can be used as a rapid indicating technique for the determining hot air stress in plants.

Background : The ginseng cool-season and semi-shade plant undergoes photosynthesis smoothly at low temperature in the morning but its efficiency falls at high temperature in the afternoon. Therefore, if it is possible to control light transmission rates (LTR) every day, it will be able to draw an ideal result in the ginseng growth by attracting a lot of lights before 11am and attracting few lights after 11am which is the affect point of the photosynthetic efficiency. Methods and Results : While installing the sun shading facility that could control the light environment based on 11am and surveying the ginseng's growth and photosynthetic characteristics. The photosynthetic efficiency increased 2.81 times compared to conventional practices without the change of the chlorophyll content although LTR was high because of the low temperature in the morning. The aboveground part growth of the ginseng which adapted to the light environment increased to influence the root weight, when the ginseng was 4 years old, the fresh root weight was averagely 33.3g per plant which increased by 81% than 18.4g of conventional practices. Conclusion : If the light environment management according with the photosynthetic nature of the ginseng is conducted based on 11am, it will be possible to produce a large capacity and excellent-quality ginseng.

Background : Excessively high concentration of sodium ion causednutrient deficiency and significantly decrease growth. This study was carried out to determine the limiting concentration range of sodium ion in the soil of ginseng field. Methods and Results : The growth of the ginseng cultivar Chunpoong reduced with increase in salinity, and the rate of growth reduction was higher in shoots than that of roots. Particularly, ginseng plants cultivated at high level of nitrate nitrogen or sodium may suffer delayed development and stunted growth. Chlorophyll damage occurred on the leaves of ginseng planted in relatively high levels (> 0.2 c㏖+/㎏) of sodium ion, as determined by the fluorescence reaction. The incidence of physiological disorder in ginseng cultivated at 249 sites was correlated with the concentration of sodium ion in the soils. About 74% of ginseng fields in which physiological disorders occurred had concentrations of sodium ion in soil greater than 0.2 c㏖+/㎏. In contrast, the concentration of sodium ions at 51 of 85 sites where no damage occurred was relatively (0.05 c㏖+/㎏- 0.15 c +/㎏). Conclusions : The concentration of sodium ion in soil of ginseng fields can be classified into three levels optimum (≤ 0.15), permissible allowance (0.15 - 0.2) and excessive (> 0.2).

The response of the freshwater microalga Chlorella vulgaris to mercuric ion (Hg2+) stress was examined using chlorophyll a fluorescence image analysis and O-J-I-P analysis as a way to monitor the toxic effects of mercury on water ecosystems. The levels of photosynthetic pigments, such as chlorophyll a and b and carotenoids, decreased with increasing Hg2+ concentration. The maximum photochemical efficiency of photosystem Ⅱ(Fv/Fm) changed remarkably with increasing Hg2+ concentration and treatment time. In particular, above 200 μM Hg2+, considerable mercury toxicity was seen within 2 h. The chlorophyll a fluorescence transient O-J-I-P was also remarkably affected by Hg2+; the fluorescence emission decreased considerably in steps J, I, and P with an increase in Hg2+ concentration when treated for 4 h. Subsequently, the JIP-test parameters (Fm, Fv/Fo, RC/CS, TRo/CS, ETo/CS, ΦPO, ΨO and ΦEO) decreased with increasing Hg2+ concentration, while N, Sm, ABS/RC, DIo/RC and DIo/CS increased. Therefore, a useful biomarker for investigating mercury stress in water ecosystems, and the parameters Fm, ΦPO, ΨO, and RC/CS can be used to monitor the environmental stress in water ecosystems quantitatively.