Fern flora and habitats of ferns in the Matsudo Campus, Faculty of Horticulture,Chiba University

摘要

Fern flora in the Matsudo campus has not been studied since 1933. To clarify existing species diversity of fernwhich is susceptible to urbanization and disturbance by planting, we made up a fern flora of the Matsudo Campus,Faculty of Horticulture, Chiba University. We found 34 taxa of ferns including 12 family, 17 genus, 31 species, 1subspecies, 1 variety, and 1 hybrid species. Thirty species including aquatic ferns such as Azolla imbricata,Salvinia natans, and Marsilea quadrifolia have disappeared from the Matsudo Campus. Extinction of the aquaticferns was possibly caused to reclamation of paddy fields. We added species that were not found in 1933, includingDryopteris sacrosancta and Polystichum × ohtanii that are rare in Chiba Prefecture. It is necessary formaintenance of the species diversity to prevent habitats of ferns from aridification that is mainly attributed tofelling and trimming of trees.