Jespersen RG, Anderson-Smith M, Sullivan PF, Dial RJ, Welker JM (2023) NDVI changes in the Arctic: Functional significance in the moist acidic tundra of Northern Alaska. PLoS ONE 18(4): e0285030. https://doi.org/10.1371/journal.pone.0285030
NDVI changes in the Arctic : functional significance in the moist acidic tundra of Northern Alaska
|Author:||Jespersen, R. Gus1; Anderson-Smith, M.2; Sullivan, P. F.3;|
1Department of Biological Sciences, University of Alaska Anchorage, Anchorage, Alaska, United States of America
2Anchorage, Alaska, United States of America
3Environment and Natural Resources Institute, University of Alaska Anchorage, Anchorage, Alaska, United States of America
4Alaska Pacific University, Anchorage, Alaska, United States of America
5Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
6University of the Arctic (UArctic), Rovaniemi, Finland
|Online Access:||PDF Full Text (PDF, 2.1 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe20230928137709
Public Library of Science,
|Publish Date:|| 2023-09-28
The Normalized Difference Vegetation Index (NDVI), derived from reflected visible and infrared radiation, has been critical to understanding change across the Arctic, but relatively few ground truthing efforts have directly linked NDVI to structural and functional properties of Arctic tundra ecosystems. To improve the interpretation of changing NDVI within moist acidic tundra (MAT), a common Arctic ecosystem, we coupled measurements of NDVI, vegetation structure, and CO₂ flux in seventy MAT plots, chosen to represent the full range of typical MAT vegetation conditions, over two growing seasons. Light-saturated photosynthesis, ecosystem respiration, and net ecosystem CO₂ exchange were well predicted by NDVI, but not by vertically-projected leaf area, our nondestructive proxy for leaf area index (LAI). Further, our data indicate that NDVI in this ecosystem is driven primarily by the biochemical properties of the canopy leaves of the dominant plant functional types, rather than purely the amount of leaf area; NDVI was more strongly correlated with top cover and repeated cover of deciduous shrubs than other plant functional types, a finding supported by our data from separate “monotypic” plots. In these pure stands of a plant functional type, deciduous shrubs exhibited higher NDVI than any other plant functional type. Likewise, leaves from the two most common deciduous shrubs, Betula nana and Salix pulchra, exhibited higher leaf-level NDVI than those from the codominant graminoid, Eriophorum vaginatum. Our findings suggest that recent increases in NDVI in MAT in the North American Arctic are largely driven by expanding deciduous shrub canopies, with substantial implications for MAT ecosystem function, especially net carbon uptake.
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
1181 Ecology, evolutionary biology
This research was supported by National Science Foundation (NSF) grants 0612534 and 0632184 to JMW and PFS and NSF grants 0856728, 1836873, 1504141, 1433063, 0909538, 0119279, and 9321730 to JMW. Additional support was provided by a Center for Global Change Fellowship awarded to MAS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
© 2023 Jespersen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.