Vegetation shifts observed in arctic tundra 17 years after fire

• Published in: Remote sensing letters Vol. 3; no. 8; pp. 729 - 736
• Main Authors: Barrett, Kirsten, Rocha, Adrian V., van de Weg, Martine Janet, Shaver, Gaius
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 01.01.2012; Taylor & Francis Ltd
• Subjects: Animal, plant and microbial ecology; Applied geophysics; Biological and medical sciences; Birds; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General aspects. Techniques; Internal geophysics; Pollution, environment geology; Remote sensing; Taiga & tundra; Teledetection and vegetation maps; Vegetation; polar regions; Alaska; United States; Arctic region; North Slope; impact statements; tundra; fires; Space remote sensing; imagery; vegetation; North America; climate change
• ISSN: 2150-704X; 2150-7058
• DOI: 10.1080/2150704X.2012.676741

With anticipated climate change, tundra fires are expected to occur more frequently in the future, but data on the long-term effects of fire on tundra vegetation composition are scarce. This study addresses changes in vegetation structure that have persisted for 17 years after a tundra fire on the North Slope of Alaska. Fire-related shifts in vegetation composition were assessed from remote-sensing imagery and ground observations of the burn scar and an adjacent control site. Early-season remotely sensed imagery from the burn scar exhibits a low vegetation index compared with the control site, whereas the late-season signal is slightly higher. The range and maximum vegetation index are greater in the burn scar, although the mean annual values do not differ among the sites. Ground observations revealed a greater abundance of moss in the unburned site, which may account for the high early growing season normalized difference vegetation index (NDVI) anomaly relative to the burn. The abundance of graminoid species and an absence of Betula nana in the post-fire tundra sites may also be responsible for the spectral differences observed in the remotely sensed imagery. The partial replacement of tundra by graminoid-dominated ecosystems has been predicted by the ALFRESCO model of disturbance, climate and vegetation succession.