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ABSTRACT Grassland ecosystems play essential roles in global carbon cycling and biodiversity conservation, yet it remains unclear whether belowground productivity is less sensitive to environmental change than aboveground productivity. Previous studies have predominantly focused on aboveground net primary productivity (ANPP) stability, potentially overestimating ecosystem vulnerability by neglecting critical belowground processes. By synthesizing 1513 observations from 113 studies across 85 grassland ecosystems worldwide, we quantified the responses of productivity, temporal stability, and carbon allocation to nine global change drivers, including nutrient enrichment, altered precipitation, elevated CO2, warming, mowing, and grazing. Our results reveal that belowground net primary productivity (BNPP) stability shows generally weaker responses to global change drivers than ANPP stability. In addition, variation in ANPP stability was most closely associated with broad‐scale climatic indices of water supply (precipitation and aridity, used here as proxies for plant‐available soil water), whereas BNPP stability was more closely associated with edaphic context (soil moisture‐related and fertility‐related properties). These distinct patterns suggest that broad‐scale climatic variability is more strongly reflected in aboveground stability, whereas belowground stability is better captured by edaphic predictors related to water retention and nutrient availability. Moreover, variation in belowground carbon allocation was consistently associated with stronger coordination between above‐ and belowground responses and with the maintenance of BNPP stability under global‐change perturbations, suggesting a potential allocation‐related pathway linked to ecosystem resistance. Our findings challenge traditional ecological theories emphasizing unified above‐belowground responses and suggest that previous research focusing solely on aboveground processes may have overestimated grassland vulnerability. This synthesis provides critical insights for predicting grassland ecosystem stability and functioning under ongoing global environmental changes.
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This content will become publicly available on November 5, 2026
Impacts and Legacies of Extreme Precipitation on Temperate Forests During Critical Ecological Windows
Within seasonal temperate forests, changes in precipitation structure—its form, duration, and seasonal timing—is a dominant characteristic of climate change. While past research has focused primarily on annual precipitation totals, emerging evidence shows that short-duration extreme precipitation can impact ecosystem carbon, water, and biogeochemical cycling when it coincides with key phenological and physiological transitions. These impacts are mediated by the responses of plant and microbial physiology, aboveground–belowground interactions, and lagged feedbacks as organisms and communities adjust to these extremes. This review focuses on shifts within ecosystem water cycling, within tree growth dynamics (carbon uptake and aboveground–belowground allocation and coordination), within soil biogeochemical cycling, from the loss of winter snow, and in forest structure and community composition. Together, these concepts highlight the urgent need to understand how changes in all aspects of precipitation structure reshape the functioning and resilience of mesic temperate forests.
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- PAR ID:
- 10659321
- Publisher / Repository:
- ANNUAL REVIEW OF ECOLOGY, EVOLUTION, AND SYSTEMATICS
- Date Published:
- Journal Name:
- Annual Review of Ecology, Evolution, and Systematics
- Volume:
- 56
- Issue:
- 1
- ISSN:
- 1543-592X
- Page Range / eLocation ID:
- 315 to 335
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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