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Abstract Climate warming is expected to stimulate plant growth in high‐elevation and high‐latitude ecosystems, significantly increasing aboveground net primary production (ANPP). However, the effects of simultaneous changes in temperature, snowmelt timing, and summer water availability on total net primary production (NPP)—and elucidation of both above‐ and belowground responses—remain an important area in need of further study. In particular, measures of belowground net primary productivity (BNPP) are required to understand whether ANPP changes reflect changes in allocation or are indicative of a whole plant NPP response. Further, plant functional traits provide a key way to scale from the individual plant to the community level and provide insight into drivers of NPP responses to environmental change. We used infrared heaters to warm an alpine plant community at Niwot Ridge, Colorado, and applied supplemental water to compensate for soil water loss induced by warming. We measured ANPP, BNPP, and leaf and root functional traits across treatments after 5 yr of continuous warming. Community‐level ANPP and total NPP (ANPP + BNPP) did not respond to heating or watering, but BNPP increased in response to heating. Heating decreased community‐level leaf dry matter content and increased total root length, indicating a shift in strategy from resource conservation to acquisition in response to warming. Water use efficiency (WUE) decreased with heating, suggesting alleviation of moisture constraints that may have enabled the plant community to increase productivity. Heating may have decreased WUE by melting snow earlier and creating more days early in the growing season with adequate soil moisture, but stimulated dry mass investment in roots as soils dried down later in the growing season. Overall, this study highlights how ANPP and BNPP responses to climate change can diverge, and encourages a closer examination of belowground processes, especially in alpine systems, where the majority of NPP occurs belowground.
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This content will become publicly available on June 5, 2026
Unveiling responses of plant performance and vegetation cover to shifting snow regimes: a meta-analysis
Snow cover is a critical factor controlling plant performance, such as survival, growth, and biomass, and vegetation cover in regions with seasonal snow (e.g., high-latitude and high elevation regions), due to its influence on the timing and length of the growing season, insulation effect during winter, and biotic and abiotic environmental factors. Therefore, changes in snow cover driven by rising temperatures and shifting precipitation patterns are expected to alter plant performance and vegetation cover. Despite the rapid increase in research on this topic in recent decades, there is still a lack of studies that quantitatively elucidate how plant performance and vegetation cover respond to shifting snow cover across snowy regions. Additionally, no comprehensive study has yet quantitatively examined these responses across regions, ecosystems, and plant functional types. Here, we conducted a meta-analysis synthesizing data from 54 snow cover manipulation studies conducted in both the field and laboratory across snowy regions to detect how plants performance and vegetation cover respond to decreased or increased snow cover. Our results demonstrate that plant survival, aboveground biomass, and belowground biomass exhibited significant decreases in response to decreased snow cover, with rates of survival having the greatest decrease. In response to increased snow cover, plant survival, growth, biomass and vegetation cover tended to increase, except for plant belowground length growth and biomass, which showed significant decreases. Additionally, our quantitative analysis of plant responses to changes in snow cover across regions, ecosystems, and plant functional types revealed that cold regions with thin snow cover, tundra and forest ecosystems, and woody species are particularly vulnerable to snow cover reduction. Overall, this study demonstrates the strong controls that snow cover exerts on plant performance, providing insights into the dynamics of snow-covered ecosystems under changing winter climatic conditions.
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- PAR ID:
- 10636402
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Climatic Change
- Volume:
- 178
- Issue:
- 6
- ISSN:
- 0165-0009
- Subject(s) / Keyword(s):
- Snow melt Snow manipulation Above-below-ground biomass Freeze-thaw cycles Winter ecology Climate change
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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