Tree-level nitrogen and carbon cycling characteristics of larch forests across a tree density gradient in northeastern Siberia, 2010-2017

• Main Authors: Hewitt, Rebecca, Alexander, Heather, Walker, Xanthe, Izbicki, Brian, Mack, Michelle
• Format: Dataset
• Language: English
• Published: Arctic Data Center 2022
• Subjects: Forests; nutrients; carbon; taiga; Tundra; Siberia
• Online Access: https://dx.doi.org/10.18739/a2c824g1h; https://arcticdata.io/catalog/view/doi:10.18739/A2C824G1H

As climate warms, tree density at the taiga-tundra ecotone is expected to increase, which may intensify competition for belowground resources in this nitrogen (N) limited environment. To determine the impacts of increased tree density on N cycling and productivity we examined edaphic properties indicative of soil N availability along with aboveground and belowground tree-level traits and stand characteristics related to carbon (C) and N cycling across a tree density gradient of monodominant larch (Larix cajanderi) at the taiga-tundra ecotone in far northeastern Siberia. In this dataset, we characterized tree-level aboveground C and N cycling metrics in 26 stands across a tree density gradient of monodominant Cajander larch (Larix cajanderi) at the taiga-tundra ecotone in far northeastern Siberia. We calculated tree-level metrics (i.e., C, N, and biomass pools, resorption, N uptake, N production, N residence time, N use efficiency). Our calculations are based on inventory data collected from 2010-2017 at the three plots located within each of the 26 stands. In brief, we measured diameter at breast height (≥ 1.4 meter (m) tall) or basal diameter (< 1.4 m tall) for each live L. cajanderi tree within each plot (i.e., belt transect with larger area for lower density). Estimates of L. cajanderi aboveground biomass were based on allometric equations and production was based on the 10- year average ring-width measurements obtained from basal cores or disks ~ 30 centimeter (cm) above the forest floor from five to 10 trees per stand. Our calculation of C and N cycling metrics are based on these biomass and productivity values for individual trees and measurements of C and N content of tree tissues.