LIGHT INJURY AND INHIBITION IN ANTARCTIC FRESHWATER PHYTOPLANKTON1
LIGHT INJURY AND INHIBITION IN ANTARCTIC FRESHWATER PHYTOPLANKTON1
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南极淡水浮游植物的光损伤和抑制1
DOI：
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发表时间：
1963
期刊：
影响因子：
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通讯作者：
B. Wood
中科院分区：
文献类型：
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作者：
C. Goldman;D. T. Mason;B. Wood
在罗斯岛埃文斯角的两个小湖中，用Cl 4研究了南极夏季24小时日光中强光强度对光合作用机制的抑制和损伤。碳固定的diel率与光强度完全不同步，在表面比在深度的效果更明显。这种抑制作用可以通过将浮游生物暴露于通过一系列分级的中性密度滤光片的入射光来定量地减少。在中午20%的入射光合光下，光合效率达到最大值（0.10兰利/分钟），而在另一个实验中，光合效率在接近前一个午夜时下降到0.06兰利/分钟。研究了温度升高对高度抑制的浮游生物光合吸收的影响，并确定了约为7的Qlo。底栖和非抑制性浮游植物的平均Qlo约为2。浮游生物在微弱的人工光下短时间暴露于阳光下，其光合速率会出现可逆的下降。这些结果的生态重要性，浮游植物生产在恶劣的南极条件下进行了讨论。在自然沃茨（Talling 1961）和藻类培养物（Sorokin和Krauss 1958）中，兰利/分钟以上的阳光对光合作用的抑制作用是众所周知的。这种抑制被表示为在表面处的碳吸收的抑制，其中光强度降低到最佳值的次表面最大值。人们还注意到，暴露在明亮的阳光下会损害随后在低光照条件下的光合作用过程，这些低光照条件下生活在冰雪覆盖下的浮游植物种群（Goldman 1963）。本文件将对这两个案例中的“禁止”和“损害”加以区分。F; ZTater选择性地吸收比可见光谱中心部分更大比例的紫外线和红外线辐射，现有证据表明，这些可见光波长是光合速率较低的原因。紫外线和红外光对各级细胞组织的破坏或抑制作用是目前备受关注的研究领域。Govindjee、Cederstrand和Rabinowitch（1961）认为色素在近红外线吸收能量是光合作用光抑制的原因。作者希望承认美国。S.南极研究计划-国家科学基金会赠款G-18020，以及海军特遣部队43的地面和空中人员的后勤支持。K. C.绿色。z现地址：英国贝德福德Sharnbrook Colworth House联合利华研究实验室
Inhibition and injury of the photosynthetic mechanism resulting from high light intensities in the 24-hr Antarctic summer daylight were studied using Cl4 in two small lakes on Cape Evans, Ross Island. The diel rates of carbon fixation were completely out of phase with light intensity, the effect being more pronounced at the surface than at depth. This inhibition could be quantitatively reduced by exposing the plankton to incident light passing a graded series of neutral density filters. A maximum rate was found at 20% of incident photosynthetic light at noon (0.10 langley/min), while photosynthetic efficiency in another experiment had decreased down to 0.06 langley/min close to the previous midnight. The effect of temperature increase upon the photosynthetic uptake in highly inhibited plankton was investigated, and a Qlo of about 7 determined. Benthic and noninhibited phytoplankton both had an average Qlo of about 2. A brief sunlight exposure of plankton kept in dim artificial light brought about a reversible depression of photosynthetic rate. The ecological importance of these results to phytoplankton production under the severe Antarctic conditions is discussed. The inhibitory effects of sunlight above INTRODUCTION 0.2 langley/min upon photosynthesis in natural waters (Talling 1961) and algal cultures (Sorokin and Krauss 1958) are well known. This inhibition is expressed as a depression of carbon uptake at the surface, with a subsurface maximum where the light intensity has decreased to an optimum value. It has also been noted that exposure to bright sunlight injured the subsequent in sitzl photosynthetic processes tremely low light conditions beneath a of phytoplankton populations living in excover of ice and snow ( Goldman 1963). A distinction between “inhibition” and “injury,” as exemplified by these two cases, will be made in this paper. F;ZTater selectively absorbs larger proportions of the ultraviolet and infrared radiation than of the central part of the visible spectrum, and available evidence suggests that these extravisible wavelengths are the cause of lower photosynthetic rates. The damaging or inhibitory effects of ultraviolet and infrared light upon cellular organization at all levels is an area of investigation presently receiving much attention. Energy absorption by pigments in the near infrared is held responsible for photoinhibition of photosynthesis by Govindjee, Cederstrand, and Rabinowitch ( 1961). The l The authors wish to acknowledge the U. S. Antarctic Research Program-National Science Foundation Grant G-18020, and the logistic support of ground and air personnel of Navy Task Force 43. Valuable assistance with the manuscript was given by K. C. Green. z Present address: Unilever Research Laboratory, Colworth House, Sharnbrook, Bedford, Eng-