Abstract
In order to work out the basic data for future coastal management and coastal sand.dune vegetation conservation, vegetation patterns on dry coastal sand dunes along the Shonan Coast of Kanagawa Prefecture were investigated phytosociologically and relationships to environmental factors were analyzed. In this study, coastal vegetation was classified into four classes, nine associations and six communities including two communities unknown in the higher units. Results from principal components analysis showed that vegetation habitats clearly differed in soil nutrients, other soil properties, frequency of cleaning and number of visitors. Salsoletea komarovii, Glehnietea littoralis and Viticetea rotundifoliae appear under low soil nitrogen content and anthropogenic disturbances, and Plantaginetea maioris and communities unknown in the higher units occur on soils with high content of fine gravel and high nitrogen content. Communities of Cynodon dactylon and Oenothera laciniata occurred widely on the Shonan Coast, but their habitats differ from each other. These results could be found on coastal sand dunes under strong human activity elsewhere in Japan. Based on these results, strict limitation to human activity on sand dunes is recommended for conservation of coastal vegetation. As all vegetation types of Shonan Coast were found in Hiratsuka City and Oiso Town, coastal vegetation in these two areas should be conserved carefully (strictly).
