Quantification of carbon and phosphorus co-limitation in bacterioplankton: new insights on an old topic.
Quantification of carbon and phosphorus co-limitation in bacterioplankton: new insights on an old topic.
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DOI：
10.1371/journal.pone.0099288
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Carrillo P
中科院分区：
文献类型：
--
作者：
Dorado-García I;Medina-Sánchez JM;Herrera G;Cabrerizo MJ;Carrillo P
由于限制浮游细菌的主要资源（例如有机碳[C]或磷[P]）的性质对淡水生态系统中有机碳的积累具有生物地球化学意义，因此需要关于细菌如何对这两种资源（单独或共同）作出反应的经验知识。我们在两个地中海淡水生态系统中进行了资源操作的田间实验（2×2因子设计，添加C，P或两者结合），营养状态（寡养与富养）和营养性质（自养与异养，以总初级生产力：呼吸比衡量）。总体而言，这两种资源协同限制浮游细菌，即细菌产量和丰度的响应幅度的两种资源相结合的是高于在两个生态系统中的加性响应。然而，细菌也积极响应于单一的P和C添加在富营养生态系统中，但不是单一的C在贫营养的一个，与细菌的C需求和藻类的C供应之间的比值的值一致。因此，营养性质，而不是营养状态的生态系统被证明是一个关键的功能，确定预期类型的资源共同限制的细菌，总结在一个拟议的理论框架。随着时间的推移，共同限制的实际类型转移和部分偏离（较小程度的协同作用）的理论预期，特别是在富营养化生态系统。这些偏差可以解释由外部生态力的生理限制的细菌，如捕食，其在我们的实验中的作用是支持由SEM（结构方程模型）测试的细菌和bacterivores的动态之间的关系。我们的研究，在淡水生态系统在全球碳循环中的作用日益得到认可，表明应进一步关注生物的相互作用，调节细菌的资源共同限制。
Because the nature of the main resource that limits bacterioplankton (e.g. organic carbon [C] or phosphorus [P]) has biogeochemical implications concerning organic C accumulation in freshwater ecosystems, empirical knowledge is needed concerning how bacteria respond to these two resources, available alone or together. We performed field experiments of resource manipulation (2×2 factorial design, with the addition of C, P, or both combined) in two Mediterranean freshwater ecosystems with contrasting trophic states (oligotrophy vs. eutrophy) and trophic natures (autotrophy vs. heterotrophy, measured as gross primary production:respiration ratio). Overall, the two resources synergistically co-limited bacterioplankton, i.e. the magnitude of the response of bacterial production and abundance to the two resources combined was higher than the additive response in both ecosystems. However, bacteria also responded positively to single P and C additions in the eutrophic ecosystem, but not to single C in the oligotrophic one, consistent with the value of the ratio between bacterial C demand and algal C supply. Accordingly, the trophic nature rather than the trophic state of the ecosystems proves to be a key feature determining the expected types of resource co-limitation of bacteria, as summarized in a proposed theoretical framework. The actual types of co-limitation shifted over time and partially deviated (a lesser degree of synergism) from the theoretical expectations, particularly in the eutrophic ecosystem. These deviations may be explained by extrinsic ecological forces to physiological limitations of bacteria, such as predation, whose role in our experiments is supported by the relationship between the dynamics of bacteria and bacterivores tested by SEMs (structural equation models). Our study, in line with the increasingly recognized role of freshwater ecosystems in the global C cycle, suggests that further attention should be focussed on the biotic interactions that modulate resource co-limitation of bacteria.
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影响因子：
1.4
作者：
Degerman, Rickard;Dinasquet, Julie;Andersson, Agneta
通讯作者：
Andersson, Agneta
影响因子：
3
作者：
BENNER, R;STROM, M
通讯作者：
STROM, M
DOI：
10.1016/j.jembe.2012.03.012
发表时间：
2012-05-01
影响因子：
2
作者：
Carlsson, Per;Graneli, Edna;Lindehoff, Elin
通讯作者：
Lindehoff, Elin
影响因子：
4.4
作者：
Anesio, AM;Granéli, W;Mopper, K
通讯作者：
Mopper, K
影响因子：
4.5
作者：
Cherrier, J;Bauer, JE;Chanton, JP
通讯作者：
Chanton, JP