Drought Exposure History of Grassland Communities Improves Its Recovery From Subsequent Drought

Drought exposure in earlier generations in the field improves complementarity between offspring of various grassland species, making them more tolerant to drought in the future.

With around 1,000 experimental plant communities in pots, an international research team discovered this transgenerational impact.

Grassland recovery

(Photo : STR/AFP via Getty Images)

The findings show that, if past catastrophic climatic events did not entirely wipe out species, they may help to ensure biodiversity and ecosystem function in the future, when extreme events occur more frequently, as per ScienceDaily.

In a major grassland biodiversity experiment in Jena, Germany, the researchers exposed experimental grassland ecosystems to eight recurring annual droughts or ambient conditions.

Afterward when, saplings from 12 distinct species were grown singly, in monocultures, or in two mixtures, before being subjected to a drought.

Plants having a history of drought exposure recovered quicker from subsequent droughts than plants without such a history; however, this was only observed when plants were cultivated in mixes rather than monocultures.

These findings showed that species in varied plant communities can develop improved cooperation through time, boosting the stability of an ecosystem in the face of external perturbation.

According to Professor Bernhard Schmid of the University of Zurich, senior author of the recent Nature Communications study, this has substantial implications for biodiversity conservation under global climate-change scenarios.

Plant communities' adaptability to harsh occurrences can be improved by conserving biodiversity.

Only if animals have shared prior events and will face future events collectively, rather than separately, is this adaptation possible.

The researchers looked at why previous drought exposure helped mixes recover faster during subsequent droughts.

They discovered that offspring from plants that had experienced drought had more species complementarity throughout the recovery period than those from plants that had not.

Species complementarity refers to the fact that certain species limit themselves more than others.

Dr. Yuxin Chen, a former postdoc at the University of Zurich who is now an associate professor at Xiamen University in China and the first author of the current publication.

According to the author, it is a vital mechanism for sustaining variety and buffering the impacts of climate change on ecosphere function.

Also Read: "Catastrophic" Drought in the Horn of Africa Kills Over a Million Livestock

The resilience of grasslands to drought

That level toward which diversification can aid grasslands in maintaining stability in the face of climate change, such as long summer droughts, has attracted interest, as per the study "Grassland Resistance and Resilience after Drought Depends on Management Intensity and Species Richness."

So far, studies have shown mixed findings, and the impact of different grassland management strategies on drought adaptation remains an unanswered subject.

Researchers discovered that the severity of treatment and the diversity of species had an influence on grasslands' tolerance and resistance to dry weather.

In one of the two research years, frequent mowing lowered grassland drought resilience, whereas increasing species richness decreased resistance.

Only the most severe management treatments revealed a connection between resilience and species diversity.

Low mowing frequency, rather than species diversity, appears to be more important for drought resilience.

In the future strengthens the fact that frequent catastrophic climatic events, this transgenerational reinforcement of species complementarity might enable mixed communities to maintain their biodiversity and ecological functioning.

Related article: California Drought Putting Trees in Bay Area 'Under Stress'