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Title: Early snowmelt projected to cause population decline in a subalpine plant
How climate change influences the dynamics of plant populations is not well understood, as few plant studies have measured responses of vital rates to climatic variables and modeled the impact on population growth. The present study used 25 y of demographic data to analyze how survival, growth, and fecundity respond to date of spring snowmelt for a subalpine plant. Fecundity was estimated by seed production (over 15 y) and also divided into flower number, fruit set, seeds per fruit, and escape from seed predation. Despite no apparent effects on flower number, plants produced more seeds in years with later snowmelt. Survival and probability of flowering were reduced by early snowmelt in the previous year. Based on demographic models, earlier snowmelt with warming is expected to lead to negative population growth, driven especially by changes in seedling establishment and seed production. These results provide a rare example of how climate change is expected to influence the dynamics of a plant population. They furthermore illustrate the potential for strong population impacts even in the absence of more commonly reported visual signs, such as earlier blooming or reduced floral display in early melting years.  more » « less
Award ID(s):
1654655 9806547 0542876
NSF-PAR ID:
10129286
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
116
Issue:
26
ISSN:
0027-8424
Page Range / eLocation ID:
12901 to 12906
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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