Various species endure evolutionary changes when a plant community is subjected to drought. An international study involving UZH researchers has now found that this leads to improved drought resilience over time.
The exposure to drought during previous generations in the field increases complementarity between offspring of different grassland species and therefore makes them more resilient to subsequent drought.
An international research group has disclosed this transgenerational impact with nearly 1,000 experimental plant communities in pots. The outcomes indicate that if past extreme climatic events do not make species go entirely extinct, they may improve the sustainability of biodiversity and ecosystem functioning in a future with more frequent extreme events.
The research group uncovered experimental grassland communities to around eight repeated annual droughts or ambient conditions in a large grassland biodiversity experiment performed in Jena, Germany.
Furthermore, the seed offspring of 12 species were grown separately, in monocultures, or two-species mixtures, and subjected to a consequent drought event that happened in a glasshouse at the University of Zurich, Switzerland.
Mixtures are Better Than Monocultures
Offspring from plants with drought-exposure history was recovered quicker from the consequent drought compared to those from plants that did not have such a history. But this was only clear when plants were made to grow in mixtures but not in monocultures.
These findings suggest that, in diverse plant communities, species over time can evolve better cooperation, thus increasing the stability of an ecosystem to disturbance from outside. This has important implications for biodiversity conservation under global climate-change scenarios.
Bernhard Schmid, Study Senior Author and Professor, University of Zurich
Schmid added, “Conserving biodiversity can improve the adaptation of plant communities to extreme events. This adaptation is only possible if species co-experienced the past events and also face the future events together, not alone.”
Schmid is the author of the present publication that has been published in the journal Nature Communications.
Transgenerational Reinforcement of Species
Furthermore, the team explored the reason as to why drought-exposure history enhanced the recovery of mixtures from the consequent drought. They discovered that offspring from plants, along with drought-exposure history, displayed a higher complementarity between species at the time of the recovery phase compared to those from plants without having such a history.
Species complementarity means that species limit themselves more than they limit others. It is a crucial mechanism for maintaining biodiversity and buffering the impacts of climate change on ecosystem functioning.
Dr. Yuxin Chen, Former Postdoc, University of Zurich
Chen added, “This transgenerational reinforcement of species complementarity may help mixed communities to sustain their biodiversity and ecosystem functioning in a future with more frequent extreme climatic events.”
Chen is currently an associate professor at Xiamen University.
Chen, Y., et al. (2022) Drought-exposure history increases complementarity between plant species in response to a subsequent drought. Nature Communications. doi.org/10.1038/s41467-022-30954-9.