Source: School of Life Sciences
Written by: School of Life Sciences
Edited by: Wang Dongmei

Recently, the research paper ‘Global evidence of positive biodiversity effects on spatial ecosystem stability in natural grasslands’ of Yongfan Wang team, the School of Life Sciences, Sun Yat-sen University, was published on Nature Communications. The study has made significant progress in biodiversity. Yongfan Wang is the first and the correspondence author of this paper, Professor Michel Loreau of the Centre for Biodiversity Theory and Modelling in France, is the co-correspondence author, Dr. Yuxin Chen has made important contributions to this research. This study was supported by the National Natural Science Foundation of China (Project 31170398, 30970472, and 31230013). The State Key Laboratory of Biocontrol has given strong support to this research.

Due to the reduction of habitats, global changes and environmental pollutions, the species on the Earth are accelerating extinction. The impact of species extinction on ecosystems has attracted great attention. In the past three decades, the relationship between biodiversity and ecosystem functioning, and the relationship between biodiversity and stability, have been studied as two different scientific issues. In particular, the relationship between biodiversity and primary productivity, the most important measure of ecosystem functioning, is one of the core issues in biodiversity research. Experimental ecologists, such as D. Tilman and A. Hector, through artificial grassland experiments in North America and Europe, have found that positive relationship between biodiversity and productivity is the main pattern, that is, biodiversity promotes primary productivity, and some biological mechanisms have been widely discussed as driving this positive relationship. However, in the grassland experiments, there is also no correlation or even negative correlation between biodiversity and productivity although a positive relationship is the most common pattern. It is difficult for the existing theories to explain these discordant relationships.

By analyzing a global survey data of natural grasslands (Herbaceous Diversity Network), Wang et al. found that there are different forms of relationship between biodiversity and productivity, no correlation is the most common pattern, followed by negative and positive correlation, which is very different from the results of experimental grasslands. Their results also show that the effect of biodiversity on primary productivity shifts from strongly positive in low productivity communities to strongly negative in high-productivity communities, biodiversity maintains community productivity at intermediate levels. Thus, they suggest that biodiversity stabilizes rather than increases plant productivity in natural grasslands at the global scale. The effects of biodiversity on productivity and on its spatial stability should be viewed as two aspects of the same ecological process, i.e., the variations in the sign and strength of interspecific interactions along a stress or productivity gradient. This study integrates biodiversity–productivity and biodiversity–stability relationships into a single unified picture at the global extent, and provides a system-level understanding of ecological processes which is likely to transform ecology into a more systematic science.

Link to the paper: https://doi.org/10.1038/s41467-019-11191-z