Fate of plants from buried seeds on Volcano Usu, Japan, after the 1977–1978 eruptions

• Published in: American Journal of Botany
• Main Author: Tsuyuzaki, Shiro
• Other Authors: Ministry of Education, Science and Culture of Japan
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1994
• Subjects: Rorippa islandica
• Online Access: http://dx.doi.org/10.1002/j.1537-2197.1994.tb15462.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fj.1537-2197.1994.tb15462.x; http://onlinelibrary.wiley.com/wol1/doi/10.1002/j.1537-2197.1994.tb15462.x/fullpdf

The eruptions of 1977–1978 on Mount Usu in northern Japan resulted in the almost complete destruction of vegetation by a 1–3‐m‐thick accumulation of volcanic deposits. Erosion created gullies that removed these deposits and frequently exposed the old original soil. I previously confirmed that seedlings of 14 species (eight annual and six perennial herbs) emerged from seeds buried in the original topsoil. To clarify the role of the seed bank on volcanic succession, I monitored seedlings of seed bank species from 1983 to 1992. Nearly all the annuals, such as Polygonum longisetum and Rorippa islandica , originated from the seed bank. However, seed supply from the seed bank declined with time. Because seedling mortality was extremely high and reproductive success was low, due mostly to the instability of ground surface, these annuals emerged for several years but disappeared after 1989. The nitrogen‐fixing and stoloniferous perennials, Trifolium repens and Lotus corniculatus var. japonicus , were derived only from the seed bank. They have gradually increased in cover and have become large enough to flower. The other perennials derived from the seed bank, most of which produce short rhizomes, did not increase in cover annually and thus contributed less to revegetation than nitrogen‐fixing stoloniferous species. The fate of perennials seems to be dependent on the types of rhizome and stolon systems. Although recruitment from the seed bank was restricted to gullies, the seed bank was the major source of annuals and of nitrogen‐fixing perennials in the gullies. Succession in the gullies was substantially different from that which occurred outside the gullies where plants mostly originated from seed immigration and vegetative reproduction from surviving plants, and annual and nitrogen‐fixing plants were absent.