Interacting species can respond differently to climate change, causing unexpected consequences. Many understorey wildflowers in deciduous forests leaf out and flower in the spring when light availability is the highest before overstorey canopy closure. Therefore, different phenological responses by understorey and overstorey species to increased spring temperature could have significant ecological implications. Pairing contemporary data with historical observations initiated by Henry David Thoreau (1850s), we found that overstorey tree leaf out is more responsive to increased spring temperature than understorey wildflower phenology, resulting in shorter periods of high light in the understorey before wildflowers are shaded by tree canopies. Because of this overstorey–understorey mismatch, we estimate that wildflower spring carbon budgets in the northeastern United States were 12–26% larger during Thoreau's era and project a 10–48% reduction during this century. This underappreciated phenomenon may have already reduced wildflower fitness and could lead to future population declines in these ecologically important species.
- NSF-PAR ID:
- 10392359
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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A number of recent studies have documented long-term declines in abundances of important arthropod groups, primarily in Europe and North America. These declines are generally attributed to habitat loss, but a recent study [B.C. Lister, A. Garcia,
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Abstract Aim Phenological mismatches, when life‐events become mistimed with optimal environmental conditions, have become increasingly common under climate change. Population‐level susceptibility to mismatches depends on how phenology and phenotypic plasticity vary across a species’ distributional range. Here, we quantify the environmental drivers of colour moult phenology, phenotypic plasticity, and the extent of phenological mismatch in seasonal camouflage to assess vulnerability to mismatch in a common North American mammal.
Location North America.
Time period 2010–2017.
Major taxa studied Snowshoe hare (
Lepus americanus ).Methods We used > 5,500 by‐catch photographs of snowshoe hares from 448 remote camera trap sites at three independent study areas. To quantify moult phenology and phenotypic plasticity, we used multinomial logistic regression models that incorporated geospatial and high‐resolution climate data. We estimated occurrence of camouflage mismatch between hares’ coat colour and the presence and absence of snow over 7 years of monitoring.
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In this study, we bridged this gap by estimating annual carbon assimilation as a function of foliar phenology and photosynthetic capacity for seedlings of two temperate tree species that commonly co‐occur across eastern North America. We then modelled the relationship between estimated carbon assimilation and observed seedling survival and growth.
Our results indicate that seedlings of both species strongly depend on spring phenological escape to assimilate the majority of their annual carbon budget and that this mechanism significantly affects their likelihood of survival (but not growth). Foliar desiccation also played a strong role in driving patterns of seedling survival, suggesting that water availability will also help shape seedling recruitment dynamics. We found only weak associations between seedling senescence in fall and annual carbon assimilation, suggesting that phenological escape in fall plays a relatively minor role in seedling demographic performance.
Our results indicate that spring phenological escape is critical for survival of these temperate tree species, and thus, any changes to this dynamic associated with climate change could strongly impact these species' recruitment.
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-022-34936-9
