Post-eruption Legacy Effects and Their Implications for Long-Term Recovery of the Vegetation on Kasatochi Island, Alaska

Abstract

We studied the vegetation of Kasatochi Island, central Aleutian Islands, to provide a general field assessment regarding the survival of plants, lichens, and fungi following a destructive volcanic eruption that occurred in 2008. Plant community data were analyzed using multivariate methods to explore the relationship between pre- and post-eruption plant cover; 5 major vegetation types were identified: Honckenya peploides beach, Festuca rubra cliff shelf, Lupinus nootkatensis–Festuca rubra meadow, Leymus mollis bluff ridge (and beach), and Aleuria aurantia lower slope barrens. Our study provided a very unusual glimpse into the early stages of plant primary succession on a remote island where most of the vegetation was destroyed. Plants that apparently survived the eruption dominated early plant communities. Not surprisingly, the most diverse post-eruption community most closely resembled a widespread pre-eruption type. Microhabitats where early plant communities were found were distinct and apparently crucial in determining plant survival. Comparison with volcanic events in related boreal regions indicated some post-eruption pattern similarities.

Acknowledgments

We thank the following taxonomic specialists for their confirmations or determinations of the following: ascomycetes—G. A. Laursen, University of Alaska (2009); bryophytes—W. B. Schofield, University of British Columbia (2001, 2003), and O. Lee, University of British Columbia (2009); graminoids—J. M. Saarela, Canadian Museum of Nature (2009); Epilobium—P. C. Hoch, Missouri Botanical Garden; miscellaneous vascular plants—A. R. Batten, University of Alaska (2001, 2003); Orchidaceae—C. J. Sheviak, New York State Museum (2001, 2003); Poaceae—R. J. Soreng, Smithsonian Institution (2001); Stellaria—J. K. Morton, University of Waterloo (2001, 2003); and lichens—J. W. Thomson, University of Wisconsin (2001, 2003). Our thanks to J. Brewer and R. Siciliano, U.S. Fish and Wildlife Service, for map production; and for the thoughtful reviews of P. Krestov (Institute of Biology and Soil Science, Vladivostok) and A. Solomeshch (University of California at Davis). Walker thanks the Department of Botany at the University of Hawaii at Manoa for support through the Wilder Chair program. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. The North Pacific Research Board (Project #923), U.S. Fish and Wildlife Service, and U.S. Geological Survey provided support for this study. This is contribution 255 of the North Pacific Research Board.