A rich body of evidence from local-scale experiments and observational studies has revealed stabilizing effects of biodiversity on ecosystem functioning. However, whether these effects emerge across entire regions and continents remains largely overlooked. Here we combine data on the distribution of more than 57,500 plant species and remote-sensing observations throughout the entire Western Hemisphere to investigate the role of multiple facets of plant diversity (species richness, phylogenetic diversity, and functional diversity) in mediating the sensitivity of ecosystems to climate variability at the regional-scale over the past 20 years. We show that, across multiple biomes, regions of greater plant diversity exhibit lower sensitivity (more stable over time) to temperature variability at the interannual and seasonal-scales. While these areas can display lower sensitivity to interannual variability in precipitation, they emerge as highly sensitive to precipitation seasonality. Conserving landscapes of greater diversity may help stabilize ecosystem functioning under climate change, possibly securing the continuous provisions of productivity-related ecosystem service to people.
Prediction of ecosystem responses to a changing climate is challenging at the landscape to regional scale, in part because topography creates various habitats and influences ecosystem productivity in complex ways. However, the effects of topography on ecosystem function remain poorly characterized and quantified. To address this knowledge gap, we developed a framework to systematically quantify and evaluate the effects of topographic convergence, elevation, aspect, and forest type on the long‐term (1986–2011) average and interannual variability of remotely sensed ecosystem productivity. In a forested watershed in the Rocky Mountains, spanning elevations from 1,800 to 4,000 m, we found a prevalent and positive influence of topographic convergence on long‐term productivity. Interannual growing season productivity was positively related to precipitation, with higher sensitivity in low elevation and highly productive areas and lower sensitivity in convergent areas. Our findings highlight the influence of topographic complexity on both long‐term and interannual variations of ecosystem productivity and have implications for understanding and prediction of ecosystem dynamics at hillslope to regional scales.
more » « less- PAR ID:
- 10381933
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Water Resources Research
- Volume:
- 56
- Issue:
- 11
- ISSN:
- 0043-1397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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