Vegetation indices do not capture forest cover variation in Upland Siberian Larch Forests
Loranty, Michael M.
Davydov, Sergey P.
Alexander, Heather D.
Mack, Michelle C.
Natali, Susan M.
Zimov, Nikita S.
MetadataShow full item record
Boreal forests are changing in response to climate, with potentially important feedbacks to regional and global climate through altered carbon cycle and albedo dynamics. These feedback processes will be affected by vegetation changes, and feedback strengths will largely rely on the spatial extent and timing of vegetation change. Satellite remote sensing is widely used to monitor vegetation dynamics, and vegetation indices (VIs) are frequently used to characterize spatial and temporal trends in vegetation productivity. In this study we combine field observations of larch forest cover across a 25 km2 upland landscape in northeastern Siberia with high-resolution satellite observations to determine how the Normalized Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) are related to forest cover. Across 46 forest stands ranging from 0% to 90% larch canopy cover, we find either no change, or declines in NDVI and EVI derived from PlanetScope CubeSat and Landsat data with increasing forest cover. In conjunction with field observations of NDVI, these results indicate that understory vegetation likely exerts a strong influence on vegetation indices in these ecosystems. This suggests that positive decadal trends in NDVI in Siberian larch forests may correspond primarily to increases in understory productivity, or even to declines in forest cover. Consequently, positive NDVI trends may be associated with declines in terrestrial carbon storage and increases in albedo, rather than increases in carbon storage and decreases in albedo that are commonly assumed. Moreover, it is also likely that important ecological changes such as large changes in forest density or variable forest regrowth after fire are not captured by long-term NDVI trends.
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Loranty, Michael M.; Davydov, Sergey P.; Kropp, Heather; Alexander, Heather D.; Mack, Michelle C.; Natali, Susan M.; Zimov, Nikita S. 2018. "Vegetation Indices Do Not Capture Forest Cover Variation in Upland Siberian Larch Forests." Remote Sens. 10, no. 11: 1686, doi:10.3390/rs10111686.
Suggested CitationLoranty, Michael M.; Davydov, Sergey P.; Kropp, Heather; Alexander, Heather D.; Mack, Michelle C.; Natali, Susan M.; Zimov, Nikita S. 2018. "Vegetation Indices Do Not Capture Forest Cover Variation in Upland Siberian Larch Forests." Remote Sens. 10, no. 11: 1686.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
DeAngelis, Kristen M.; Pold, Grace; Topcuoglu, Begum D.; van Diepen, Linda T. A.; Varney, Rebecca M.; Blanchard, Jeffrey L.; Melillo, Jerry M.; Frey, Serita D. (Frontiers Media, 2015-02-13)Soil microbes are major drivers of soil carbon cycling, yet we lack an understanding of how climate warming will affect microbial communities. Three ongoing field studies at the Harvard Forest Long-term Ecological Research ...
Long-term CO2 enrichment of a forest ecosystem : implications for forest regeneration and succession Mohan, Jacqueline E.; Clark, James S.; Schlesinger, William H. (Ecological Society of America, 2007-06)The composition and successional status of a forest affect carbon storage and net ecosystem productivity, yet it remains unclear whether elevated atmospheric carbon dioxide (CO2) will impact rates and trajectories of forest ...
Steeper declines in forest photosynthesis than respiration explain age-driven decreases in forest growth Tang, Jianwu; Luyssaert, Sebastiaan; Richardson, Andrew D.; Kutsch, Werner; Janssens, Ivan A. (2014-04)The traditional view of forest dynamics originated by Kira, Shidei, and Odum suggests a decline in net primary productivity (NPP) in ageing forests due to stabilized gross primary productivity (GPP) and continuously increased ...