Climate change impact greater on marine systems
New international research reveals warming in temperate regions leads to species gains at sea, but not on land.
Based on a media release by the University of St Andrews
Temperature changes lead to clear biodiversity responses in marine systems, where warming coincided with increases in the number of species in most locations. These increases in the number of species are likely caused by the influx of climate migrants from species-rich warmer regions. These are the results of a new research, led by scientists from the Universities of Helsinki, St Andrews and Radboud, in collaboration with researchers from the German Centre for Integrative Biodiversity Research (iDiv) and Martin Luther University Halle-Wittenberg (MLU). published in Nature Ecology and Evolution and focussed on linking biodiversity change to temperature change, and on comparing responses between ocean and land. The research was published in Nature Ecology and Evolution and focussed on linking biodiversity change to temperature change, and on comparing responses between ocean and land.
The researchers found that increases in the number of species were more pronounced in warmer marine areas, where, on the other hand, the numbers of individuals tended to decrease with warming. By contrast, the study did not detect any systematic responses on land, despite a larger increase in temperature, but this is not to say that temperature change is not affecting terrestrial biodiversity. The research team suggests that this result is linked to species on land having wider tolerance and more strategies to avoid warming temperatures compared to ocean organisms. For example, land-based organisms have access to small pockets of suitable climate even if the wider region is warming substantially. However, these findings also suggest that terrestrial species might be lagging behind and not keeping pace with temperature change, known as a “climatic debt”.
The international team used 21,500 biodiversity time series from temperate regions around the globe from the BioTIME database, measuring the change in the number of species and in the total number of organisms through time. Then the research team related these changes with air and ocean temperature changes over the same time periods in each location.
Dr Maria Dornelas, co-senior author from the University of St Andrews, said: “We knew that climate change is having clear and important effects on the distribution of species. We also knew marine heat waves can cause dramatic die offs, but we didn’t know its net effect on the numbers of species.”
Lead researcher Laura Antão from the University of Helsinki added: “We expected to see marine communities responding faster, but were surprised that we could not find consistent responses across our locations on land. As we add more and more pieces describing how ocean and land biodiversity responses are different, further studies are needed to understand what might explain these differences.”
Despite using the largest global database of standardized biodiversity time series, the study focused only on the temperate regions of the globe, since monitoring data from polar and tropical regions remains scarce. As the world is committed to further warming, with 2020 set to be the hottest year on record, substantial challenges remain in maintaining local biodiversity amongst increased climate-related migration. Quantifying how and where biodiversity is changing is crucial given the urgent need to halt current rates of biodiversity loss.
(Scientists with iDiv affiliation in bold)
Laura H. Antão, Amanda E. Bates, Shane A. Blowes, Conor Waldock, Sarah R. Supp, Anne E. Magurran, Maria Dornelas, Aafke M. Schipper (2020). Temperature-related biodiversity change across temperate marine and terrestrial systems. Nature Ecology and Evolution, DOI: 10.1038/s41559-020-1185-7
Dr Shane Blowes
German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig
Martin Luther University Halle-Wittenberg
Phone: +49 341 9733254