Photo-degradation effect on dissolved organic carbon availability to bacterioplankton in a lake in the upper Paraná river floodplain
Photo-degradation effect on dissolved organic carbon availability to bacterioplankton in a lake in the upper Paraná river floodplain
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DOI：
10.4025/actascibiolsci.v35i1.11054
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发表时间：
2013-12
期刊：
影响因子：
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通讯作者：
M. C. Teixeira;J. C. D. Azevedo;T. A. Pagioro
中科院分区：
文献类型：
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作者：
M. C. Teixeira;J. C. D. Azevedo;T. A. Pagioro
溶解有机碳（DOC）是目前公认的水生微生物群落的主要基质和能量来源。在几乎所有的自然沃茨中，腐殖物质是DOC的主要组成部分，浮游细菌的有效有机碳大部分可能是在腐殖物质光解后形成的。DOC的光降解的影响进行了评估，因为它的利用浮游细菌，通过两个步骤的实验，一个涉及DOC的光降解和其他细菌生长的光降解基板。光降解是负责消耗19%的DOC，减少SUVA 254，E2/E3和E3/E4的比例增加，除了在荧光光谱的修改，表明DOC的不稳定部分上升。然而，DOC上的这些变化并没有反映在浮游细菌生长的差异，如所示的事实，有没有处理和对照之间的密度，生物量，细菌生产，细菌呼吸和细菌生长效率的显着差异。
Dissolved organic carbon (DOC) is nowadays recognized as the main substrate and source of energy for aquatic microbial community. The great part of available organic carbon for bacterioplankton might be formed after photolytic degradation of humic material, which constitutes the major part of DOC in almost all natural waters. The effects of DOC photo-degradation were evaluated, as was its utilization by bacterioplankton, through a two-step experiment, one involving photo-degradation of DOC and the other bacterial growth on the photo-degraded substrate. Photo-degradation was responsible for the consumption of 19% of DOC, reduced SUVA254, an increase in the E2/E3 and E3/E4 ratios, in addition to modifications in the fluorescence spectra that indicated a rise in the labile fraction of DOC. However, these alterations on DOC were not reflected in differences in bacterioplankton growth, as shown by the fact that there were no significant differences in density, biomass, bacterial production, bacterial respiration and bacterial growth efficiency between treatment and control.