Tundra plant above-ground biomass and shrub dominance mapped across the North Slope of Alaska

Logan T. Berner, Patrick Jantz, Ken D. Tape, Scott J. Goetz

Research output: Contribution to journalArticlepeer-review

47 Scopus citations

Abstract

Arctic tundra is becoming greener and shrubbier due to recent warming. This is impacting climate feedbacks and wildlife, yet the spatial distribution of plant biomass in tundra ecosystems is uncertain. In this study, we mapped plant and shrub above-ground biomass (AGB; kg m-2) and shrub dominance (%; shrub AGB/plant AGB) across the North Slope of Alaska by linking biomass harvests at 28 field sites with 30 m resolution Landsat satellite imagery. We first developed regression models (p < 0.01) to predict plant AGB (r 2 = 0.79) and shrub AGB (r 2 = 0.82) based on the normalized difference vegetation index (NDVI) derived from imagery acquired by Landsat 5 and 7. We then predicted regional plant and shrub AGB by combining these regression models with a regional Landsat NDVI mosaic built from 1721 summer scenes acquired between 2007 and 2016. Our approach employed a Monte Carlo uncertainty analysis that propagated sampling and sensor calibration errors. We estimated that plant AGB averaged 0.74 (0.60, 0.88) kg m-2 (95% CI) and totaled 112 (91, 135) Tg across the region, with shrub AGB accounting for ∼43% of regional plant AGB. The new maps capture landscape variation in plant AGB visible in high resolution satellite and aerial imagery, notably shrubby riparian corridors. Modeled shrub AGB was strongly correlated with field measurements of shrub canopy height at 25 sites (rs = 0.88) and with a regional map of shrub cover (rs = 0.76). Modeled plant AGB and shrub dominance were higher in shrub tundra than graminoid tundra and increased between areas with the coldest and warmest summer air temperatures, underscoring the fact that future warming has the potential to greatly increase plant AGB and shrub dominance in this region. These new biomass maps provide a unique source of ecological information for a region undergoing rapid environmental change.

Original languageEnglish (US)
Article number035002
JournalEnvironmental Research Letters
Volume13
Issue number3
DOIs
StatePublished - Mar 2018

Keywords

  • arctic boreal vulnerability experiment (ABoVE)
  • arctic greening
  • carbon stock
  • climate change
  • google earth engine
  • landsat, normalized difference vegetation index (NDVI)

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Environmental Science(all)
  • Public Health, Environmental and Occupational Health

Fingerprint

Dive into the research topics of 'Tundra plant above-ground biomass and shrub dominance mapped across the North Slope of Alaska'. Together they form a unique fingerprint.

Cite this