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Abstract Climate change poses a growing threat to many ecosystems, including grasslands, which are a current priority for conservation due to their vulnerability to interacting threats from human activity.North American grasslands are expected to experience warmer temperatures and more frequent and severe droughts in the coming decades, with potential consequences for native biodiversity.We conducted an experiment at Cedar Creek Ecosystem Science Reserve, Minnesota, USA, to investigate how warming and drought treatments affected grassland plant community structure over 6 years in plots planted with species mixtures.Warming consistently reduced plant species richness with its effects on Shannon diversity (which additionally considers species' relative abundances) and dominance varying across years. These warming‐by‐year interactions were likely driven by temporal variability in environmental conditions and species‐specific responses. Notably, legumes consistently showed positive responses to warming.Drought alone had minimal direct effects on species richness and diversity but reduced variability in diversity responses over time, suggesting greater stability of diversity under drought conditions.Synthesis. This study underscores the important role of warming in reducing species richness, altering diversity and reshaping functional group composition in grassland ecosystems. While temporal variability influenced the magnitude of warming effects on diversity, legumes' positive responses highlight the importance of functional group dynamics in potentially buffering against species loss. Long‐term experiments that allow consideration of interannual variability are essential for improving predictions of ecosystem responses and informing adaptive management strategies aimed at sustaining biodiversity and ecosystem functioning in grasslands.
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This content will become publicly available on February 1, 2027
Plant elemental diversity increases ecosystem productivity and temporal stability
Abstract The elemental composition of organisms (i.e., the elementome) directly constrains metabolic machinery and aligns with functional traits, linking organismal performance to nutrient cycling and energy flow at the ecosystem level. In theory, elemental diversity captures the community functional heterogeneity by quantifying variation in the multidimensional elementomes of co‐occurring species within a community. However, empirical evidence connecting organismal elemental diversity to ecosystem functioning and identifying its environmental controls remains scarce. We compiled an unprecedented dataset on plant elemental concentrations, encompassing more than 2500 species and 14 analyzed elements (including macronutrients, micronutrients, and trace elements) sampled from leaves, stems, trunks, and fine roots across 8 biomes and 72 sites, covering multiple ecosystem types including forests and grasslands. Using these data, we investigated the spatial patterns and drivers of plant elemental diversity and evaluated its relationship with ecosystem productivity and stability. Our results indicate that plant elemental diversity decreased with latitude, with interannual variability in temperature and mean annual precipitation as the primary controls on its spatial distribution. Moreover, ecosystems with higher plant elemental diversity exhibit greater efficiency in the use of carbon, water, and light, thereby translating into higher productivity and greater temporal stability across and within forests and grasslands, and these effects persisted even after accounting for climate and soil factors. Taken together, our results support the influence of plant elemental diversity as a distinct dimension of biodiversity with functional implications. Complementing trait‐ and taxonomy‐based measures, plant elemental diversity improves predictions of ecosystem productivity and temporal stability under ongoing climatic variability, and can substantially advance research on biodiversity and ecosystem functioning.
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- Award ID(s):
- 2520925
- PAR ID:
- 10710010
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecological Monographs
- Volume:
- 96
- Issue:
- 1
- ISSN:
- 0012-9615
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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