Behaviour of terrestrial ecosystems is governed by only three main factors

Ecosystems provide multiple services for humans. However, these services depend on basic ecosystem functions which are shaped both by natural conditions like climate and species and human interventions. A large international research team, led by Max Planck Institute for Biogeochemistry, Jena, now identified three key groups of functions that fully summarize ecosystem behaviour.  The first function is the capacity to maximize primary productivity, the second one is the efficiency to use water, and third the efficiency of using carbon. The sole monitoring of these key factors will allow to describe ecosystem behaviour and to understand the responsiveness to climatic and environmental changes.

Lianes, Station des Nouragues, Guyane © CNRS Photothèque – DELHAYE Claude

Ecosystems on Earth’s land surface support multiple functions and services that are critical for society, like biomass production, the vegetation’s efficiency of using sun-light and water, water retention and climate regulation, and ultimately food security. Climate and environmental changes as well as anthropogenic impacts are continuously threatening the provision of these functions. To understand how terrestrial ecosystems will respond to this threat, it is crucial to know which functions are essential to obtain a good representation of the ecosystems’ overall well-being and behaviour. This is particularly difficult since ecosystems are rather complex regarding their structure and their responses to environmental changes.

Scientists from INRAE contributed to a large international network of researchers, led by Dr. Mirco Migliavacca at Max Planck Institute for Biogeochemistry in Jena, Germany, to tackle this question by combining multiple data streams and methods. The scientists used environmental data from global networks of ecosystem stations, combined with satellite observations, mathematical models, and statistical and causal discovery methods.  The result is strikingly simple: “We were able to identify three key dimensions that allow to summarise how ecosystems behave: the maximum realized productivity, the efficiency of using water, and the efficiency of using carbon” says Dr. Migliavacca, first author of the recent publication in Nature. “Using only these three major factors, we can explain 71.8 percent of the variability within ecosystem functions”, he adds.

Reference

Migliavacca, M., …, Mahecha, M., …, Kattge, J., & Reichstein, M. (2021): The three major axes of terrestrial ecosystem function, Nature, DOI: 10.1038/s41586-021-03939-9

Contacts

Damien Bonal Unité mixte de recherche SILVA

Clément Sthal Unité mixte de recherche EcoFOG

Download the press release here.