Causes and prediction of abrupt climate-driven ecosystem shifts in the North Atlantic

Warming of the global climate is now unequivocal and its impact on Earth’ functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod in order to minimize social and economic consequences.

2015 David Cushing Prize

The prize honors the memory of David Cushing, Founding Editor of Journal of Plankton Research. It is awarded annually for the best paper by an early career stage scientist published in the journal during the previous year. The prize helps foster the interesting and high-quality papers by young scientists that David Cushing so actively supported. The 2015 David Cushing Prize has been awarded to Bingzhang Chen for his paper, “Patterns of thermal limits of phytoplankton” (J. Plankton Res. 37, 285–292) Bingzhang Chen obtained his PhD with a major in Marine Environmental Science at the Hong Kong University of Science and Technology under the supervision of Dr Hongbin Liu in 2008. He also worked with Dr Zoe Finkel and Dr Andrew Irwin in Mount Allison University, Canada, from 2009 to 2010. During this time, he started to learn the R language and entered the field of data analysis and programming. This experience has been proved very useful for his later work.

2015 David Cushing Prize

The prize honors the memory of David Cushing, Founding Editor of Journal of Plankton Research. It is awarded annually for the best paper by an early career stage scientist published in the journal during the previous year. The prize helps foster the interesting and high-quality papers by young scientists that David Cushing so actively supported. The 2015 David Cushing Prize has been awarded to Bingzhang Chen for his paper, “Patterns of thermal limits of phytoplankton” (J. Plankton Res. 37, 285–292) Bingzhang Chen obtained his PhD with a major in Marine Environmental Science at the Hong Kong University of Science and Technology under the supervision of Dr Hongbin Liu in 2008. He also worked with Dr Zoe Finkel and Dr Andrew Irwin in Mount Allison University, Canada, from 2009 to 2010. During this time, he started to learn the R language and entered the field of data analysis and programming. This experience has been proved very useful for his later work.

Contrasting transcriptome response to thermal stress in two key zooplankton species, Calanus finmarchicus and C. glacialis

Climate change has already led to the range expansion of warm-water plankton assemblages in the northeast Atlantic and the corresponding range contraction of colder-water species. The temperate copepod Calanus finmarchicus is predicted to shift farther northward into polar waters traditionally dominated by the arctic copepod C. glacialis. To identify temperaturemediated changes in gene expression that may be critical for the thermal acclimation and resilience of the 2 Calanus spp., we conducted a whole transcriptome profiling using RNA-seq on an Ion Torrent platform. Transcriptome responses of C. finmarchicus and C. glacialis from Disko Bay, west Greenland, were investigated under realistic thermal stresses (at + 5, +10 and +15°C) for 4 h and 6 d. C. finmarchicus showed a strong response to temperature and duration of stress, involving up-regulation of genes related to protein folding, transcription, translation and metabolism. In sharp contrast, C. glacialis displayed only low-magnitude changes in gene expression in response to temperature and duration of stress. Differences in the thermal responses of the 2 species, particularly the lack of thermal stress response in C. glacialis, are in line with laboratory and field observations and suggest a vulnerability of C. glacialis to climate change.