Forest abundance data for the Abies concolor and Abies magnifica ecotone in the central Sierra Nevada range, California

This publication includes forest composition and structure data from two observational field studies conducted across the Abies concolor-Abies magnifica ecotone in the central Sierra Nevada range of California, and data from a growth chamber experiment designed to evaluate the sensitivity of Abies concolor and Abies magnifica seedling growth and survival to current and projected future climate conditions. The 1981 field study includes tree size and abundance measurements collected in 30 plots located on sites with equal abundances of Abies concolor and Abies magnifica overstory trees along the Tioga Pass Road and Glacier Point Roads in Yosemite National Park, California. The 2016 field study includes tree size and abundance measurements collected in 60 plots randomly located on north-facing aspects across an elevation gradient that spans the lower and upper elevation bounds of the Abies concolor and Abies magnifica ecotone in the central Sierra Nevada Range of California. Plots in 2016 were distributed across the Tioga Pass Road and Glacier Point areas in Yosemite National Park, and the Crabtree and Herring Creek areas in the Stanislaus National Forest. Also included are historic and projected future climate data (1981-2010, RCP 8.5 2040-2069, RCP 8.5 2070-2099) extracted at 2016 plot locations using ClimateNA software. Finally, seedling survival and biomass growth measurements were collected in a fully factorial growth chamber experiment that assessed the effects of present (2001-2010), projected mid-21st century (2040-2069), and projected late-21st century (2070-2099) temperature, soil drying, and growing season length conditions. Each of 27 treatment combinations was replicated with 14 seedlings per species. Climate conditions were based on predictions made by the Canadian Centre for Climate Modelling and Analysis (CanESM2) under the RCP 8.5 emissions forcing scenario.
2016 Field Observational Study: Seedling, sapling and tree demography was assessed across an elevation gradient that encompassed the lower and upper elevation bounds of the Abies concolor and Abies magnifica ecotone in the central Sierra Nevada Range of California. The purposes of these data were to a) determine the lower and upper elevational bounds of the ecotone, b) evaluate macro-climate drivers of species-specific tree abundances, and c) determine whether species demography is shifting under recent climate conditions. 1981 Field Observational Study: Seedling, sapling, and tree composition was assessed in an Abies concolor and Abies magnifica ecotone in the central Sierra Nevada Range of California to determine the environmental conditions encountered in these ecotone communities, and to determine site differentiation between Abies concolor and Abies magnifica tree species. 2016 Growth Chamber Experiment: The sensitivity of Abies concolor and Abies magnifica seedlings growth and survival to current and projected climate conditions was tested in a growth chamber experiment to better understand how these two species might respond to future climate conditions.
These data were published on 07/15/2021. Minor metadata updates were made on 11/22/2024.