2021 Volume 38 Issue 1 Pages 1-16
In this study, we surveyed plant species composition at sites with varying light conditions and ground water levels (GWLs) in Nyukasa Marsh, Nagano Prefecture, Japan. The 66 study sites were classified into six community types (A-F) based on cluster analysis. Plotting study sites using non-metric multidimensional scaling revealed that light conditions and GWLs affected species composition. Sites with both high GWLs and light levels were characterized by wetland species such as Carex thunbergii var. thunbergii. Conversely, sites with high GWLs but low light levels were distinguished by other wetland species such as Impatiens noli-tangere. Sites with low GWLs and high light levels supported flowering plants such as Convallaria majalis var. manshurica and Iris ensata, which are eye-catching and potentially attractive for tourists. Wet sites with moderate light levels were classified into two community types, each with unique indicator species. Sites with both low GWLs and light levels mostly comprised forest-floor and pasture species, indicating vegetational succession caused by the drying out of wetland.
