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.

本数据集涵盖阿拉斯加布鲁克斯山脉林线（treeline）的实测数据与估算变量值，包含以下内容：2018至2022年间在林线以上发现的拓殖林木点位；1970年代至2010年代通过重复影像获取的森林推进速率；2015-2020年幼树主梢生长速率与2019年成年植株侧枝生长速率；幼树（saplings）数量；2019-2022年的2米高空气温与10厘米深土壤温度；2019年土壤含水量；2020、2021及2022年1月的积雪深度估算值；叶片氮、磷含量；以及叶片的氮（¹⁵N:¹⁴N）与碳（¹³C:¹²C）稳定同位素比值。本数据集旨在揭示海冰消退对林线推进的影响。