Ecosystem study finds that the higher the environmental stress, the lower the resistance to global change

An international study conducted by the Institute of Natural Resources and Agrobiology of Seville (IRNAS-CSIC), of the Spanish National Research Council (CISC), has shown that as the number of global change factors increases, terrestrial ecosystems become more sensitive to the impacts of global change.

The results, published in the journal Geosciences of natureshow that the resistance of our ecosystems to global change decreases significantly as the number of environmental stressors increases, particularly when this stress is maintained over time.

This is the conclusion reached by the Biodiversity and Ecosystem Functioning Laboratory (BioFunLab) of IRNAS-CSIC after analyzing 1,023 experiments on global change worldwide in collaboration with 10 international institutions, including the German Center for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, the University of Alicante, the Northeast Forestry University of China, the Massachusetts Institute of Technology (MIT) in the United States and the University of New South Wales in Australia.

“Terrestrial ecosystems are subject to a multitude of climate change and environmental degradation drivers, including global warming, drought processes, air pollution, fires or overgrazing, among others. We know that these global change drivers impact the ability of our ecosystems to provide services such as carbon sequestration or soil fertility, which are essential in the fight against climate change and in food production.

“What we didn’t know is how the increase in the number of global change drivers affects the ability of ecosystems to resist this global change,” says Manuel Delgado Baquerizo, head of BioFunLab and lead author of the article.

“Our research shows that as the number of global change drivers we subject our ecosystems to increases, they become increasingly sensitive and reduce their natural capacity to withstand the impacts of environmental disturbances.”

The study also demonstrates that the persistent effects of global change on terrestrial ecosystems contribute to reducing the natural capacity of ecosystems to withstand an increase in the number of global change drivers. This conclusion was drawn from the analysis of 15 years of data from an experiment conducted in the United States that examined the impacts of multiple global change drivers on ecosystem services as important as primary production.

“Our results show that prolonged exposure to multiple drivers of global change, such as increased CO₂ “Global warming and rising temperatures are progressively reducing the capacity of ecosystems to maintain essential services such as primary productivity. This is essential to understand the limitations we will face in vital resources such as water and nitrogen,” explains Emilio Guirado, co-author of the study from the University of Alicante.

“Our study shows that increasing global change drivers will significantly reduce the resilience of ecosystems to global change. However, this effect is much more pronounced on the ability of ecosystems to provide us with ecosystem services than on the biodiversity of our ecosystems,” says Guiyao Zhou, lead author of the study and member of BioFunLab.

“These results show that the sustainability of our ecosystems depends on reducing the number of global drivers of change associated with human activity,” Zhou concludes.