Data from: Reproduction as a bottleneck to treeline advance across the circumarctic forest tundra ecotone ...

• Main Authors: Brown, Carissa D., Dufour-Tremblay, Geneviève, Jameson, Ryan G., Mamet, Steven D., Trant, Andrew J., Walker, Xanthe J., Boudraeu, Stéphane, Harper, Karen A., Henry, Greg H.R., Hermanutz, Luise, Hofgaard, Annika, Isaeva, Ludmila, Kershaw, G. Peter, Johnstone, Jill F., Henry, Gregory H. R.
• Format: Dataset
• Language: unknown
• Published: The University of British Columbia 2020
• Subjects: Climate change; Tundra
• Online Access: https://dx.doi.org/10.14288/1.0397554; https://doi.library.ubc.ca/10.14288/1.0397554

Abstract The fundamental niche of many species is shifting with climate change, especially in sub-arctic ecosystems with pronounced recent warming. Ongoing warming in sub-arctic regions should lessen environmental constraints on tree growth and reproduction, leading to increased success of trees colonising tundra. Nevertheless, variable responses of treeline ecotones have been documented in association with warming temperatures. One explanation for time lags between increasingly favourable environmental conditions and treeline ecotone movement is reproductive limitations caused by low seed availability. Our objective was to assess the reproductive constraints of the dominant tree species at the treeline ecotone in the circumpolar north. We sampled reproductive structures of trees (cones and catkins) and stand attributes across circumarctic treeline ecotones. We used generalized linear mixed models to estimate the sensitivity of seed production and the availability of viable seed to regional climate, stand ...