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Tree-ring widths from 1576 white spruce trees growing at 78 treelines distributed across 19 research sites along a longitudinal gradient in the Brooks Range of northern Alaska. The general purpose of the sampling was to examine west-east variation in white spruce growth responses to changes in climate. Trees were sampled at both high ("alpine") and low elevation treelines ("arctic"). Increment cores were collected in August and September of 2022 as low as possible on each tree (~25 centimeter height). Trees indicated with an "f" were treated with NPK (nitrogen, phosphorus, potassium) fertilizer in June of 2019 and June of 2021.
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White spruce (Picea gluaca) at Brooks Range treelines in Alaska: colonists, forest advance, reproduction, recruitment, growth, and physiochemical condition, (2019-2022)
This dataset includes measurements and estimated variable values from treelines in Alaka's Brooks Range mountains. It includes locations of colonists above treelines found in 2018, 2019, 2020, 2021, and 2022; forest advance rates from the 1970s to 2010s from repeat imagery; growth rates of leaders of juveniles during 2015-2020 and lateral branch growth of adults in 2019; counts of saplings; temperatures of air at 2 meters (m) and soil at 10 centimeters (cm) from 2019-2022; soil moisture in 2019; estimated snow depth in January 2020, 2021, and 2022; foliar nitrogen and phosphorous; and foliar stable isotope ratios for nitrogen (15N:14N) and carbon (13C:12C). The purpose of the dataset is to show the effect of sea ice retreat on treeline advance.
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- PAR ID:
- 10468978
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- boreal forest advance sea ice retreat treeline white spruce foliar nutrients seedling to sapling recruitment snow soil temperature air temperature soil moisture forest tundra ecotone Arctic Alaska Brooks Range 15N 13C foliar N foliar P cone counts seedling growth rate adult growth rate winter
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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