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Abstract After 25 years of biodiversity experiments, it is clear that higher biodiversity (B) plant communities are usually more productive and often have greater ecosystem functioning (EF) than lower diversity communities. However, the mechanisms underlying this positive biodiversity–ecosystem functioning (BEF) relationship are still poorly understood.The vast majority of past work in BEF research has focused on the roles of mathematically partitioned complementarity and selection effects. While these mathematical approaches have provided insights into underlying mechanisms, they have focused strongly on competition and resource partitioning.Importantly, mathematically partitioned complementarity effects include multiple facilitative mechanisms, including dilution of species‐specific pathogens, positive changes in soil nutrient cycling, associational defence and microclimate amelioration.Synthesis. This Special Feature takes an experimental and mechanistic approach to teasing out the facilitative mechanisms that underlie positive BEF relationships. As an example, we demonstrate diversity‐driven changes in microclimate amelioration. Articles in this Special Feature explore photoinhibition, experimental manipulations of microclimate, lidar examinations of plant canopy effects and higher‐order trophic interactions as facilitative mechanisms behind classic BEF processes. We emphasize the need for future BEF experiments to disentangle the facilitative mechanisms that are interlinked with niche complementarity to better understand the fundamental processes by which diversity regulates life on Earth.
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Mechanistic links between biodiversity effects on ecosystem functioning and stability in a multi‐site grassland experiment
Abstract Although the positive effects of biodiversity on ecosystem functioning and stability have been extensively documented in the literature, previous studies have mostly explored the mechanisms of functioning and stability independently. It is unclear how biodiversity effects on functioning may covary with those on stability.Here we developed an integrated framework to explore links between mechanisms underlying biodiversity effects on functioning and those on stability. Specifically, biodiversity effects on ecosystem functioning were partitioned into complementarity effects (CE) and selection effects (SE), and those on stability were partitioned into species asynchrony and species stability. We investigated howCEandSEwere linked to species asynchrony and stability and how their links might be mediated by species evenness, using a multi‐site grassland experiment.Our mixed‐effects models showed that a higher community productivity was mainly due toCEand a higher community stability was mainly due to species asynchrony. Moreover,CEwas positively related to species asynchrony, thus leading to a positive association between ecosystem productivity and stability.We used a structural equation model to illustrate how species evenness might mediate links between the various mechanisms. Communities with a higher evenness exhibited a higherCEand species asynchrony, but a lowerSEand species stability. These evenness‐mediated associations enhanced the positive relationship betweenCEand species asynchrony, but blurred that betweenSEand species asynchrony.Synthesis. Our findings demonstrate mechanistic links between biodiversity effects on ecosystem functioning and stability. By doing so, our study contributes a novel framework for understanding ecological mechanisms of the functioning–stability relationship, which has important implications for developing management plans focused on strengthening synergies between ecosystem functioning and stability over the long term.
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- PAR ID:
- 10450142
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Ecology
- Volume:
- 109
- Issue:
- 9
- ISSN:
- 0022-0477
- Page Range / eLocation ID:
- p. 3370-3378
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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