2025-11-12 中国科学院(CAS)
Dark-colored lichens on the Antarctica. (Image by AIRCAS)
<関連情報>
- https://english.cas.cn/newsroom/research_news/earth/202511/t20251113_1115123.shtml
- https://www.cell.com/the-innovation/fulltext/S2666-6758(25)00325-X
見落とされてきた暗色地衣類:リモートセンシングによる南極の植生マッピングの盲点 The overlooked dark-colored lichens: Blind spots in Antarctic vegetation mapping with remote sensing
Wenjin Wu ∙ Alatanzhula, ∙ Guillermo Martínez Pastur ∙ … ∙ Yuhan Xie ∙ Xinwu Li ∙ Huadong Guo
The Innovation Published:September 24, 2025
DOI:https://doi.org/10.1016/j.xinn.2025.101122
Main text
Lichens are highly tolerant of extreme climates and are widely distributed in Antarctica. As pioneer species, they can fix nitrogen, break down rocks, absorb water, and stabilize soil, which helps create conditions for higher plants and supports biodiversity and ecosystem stability in Antarctica.1 However, conventional remote sensing based on spectral indices often struggles to detect lichens.2 The normalized difference vegetation index (NDVI), widely used to estimate vegetation density, relies on red and near-infrared (NIR) reflectance, with larger differences indicating higher values. However, dark-colored lichens exhibit relatively low NIR compared with red reflectance, resulting in persistently low NDVI (Figure 1A). Other indices, such as the enhanced vegetation index or the chlorophyll/carotenoid index, which target vegetation structure or pigment composition, also exhibit limited sensitivity for dark-colored lichens due to weaker red-edge and green band signals compared with vascular plants.2 Consequently, the extent and distribution of Antarctic vegetation are often underestimated and remain incompletely quantified. Recently, Walshaw et al. presented a satellite-derived map of vegetation, including vascular plants, bryophytes, green algae, and lichens across Antarctica based on Sentinel-2 imagery and spectral indices. They also noted the limitations of their method in detecting dark-colored lichens.3 Building on their results, here we examine how these limitations affect Antarctic vegetation mapping using multiple field investigation datasets.
