Coastal vegetation of sandy beach usually shows zonal distribution along the environmental gradient as distance from the seashore increases. However, rocky coasts often have azonal habitats that do not conform to this transitional gradient. Small wetlands primarily fed by fresh water are an example of such habitats. We surveyed small wetlands along the coast of northern Sanriku area, Tohoku district of Japan, to clarify their features and role as plant habitats. The results of the field survey showed that small wetlands were divided into five types based on their topographic and hydrological features; tidal-flat, pool, back-marsh, slope, and streamside type. All types of wetlands were fed by supplies of fresh water, however, their water quality and temperature differed considerably among the different types. The stagnant water of the tidal-flat and pool type wetlands had relatively high pH and EC value, reflecting the influence of sea water. The flora in these wetland types included many salt-marsh plants. In addition, some submerged and emerged plants that prefer brackish water were present in the pool type wetlands. The slope type wetlands had developed black soil, and the back-marsh type had peat-like soil on the surface. These types supported rich flora, including elements of semi-natural grassland vegetation and fen vegetation. The streamside wetlands fed by spring outflows had rocky epiphytes and oligotrophic-moor plants, including several bryophytes. Stable low water temperature during summer was considered to be important for the appearance of these plants in the streamside types. Based on these results, the small wetlands were determined to be the particular environment of the coastal ecotone, because they require the influence of both terrestrial and aquatic ecosystems to sustain themselves. Furthermore, the existence of different types of small wetlands considerably contributed to the species richness of coastal vegetation by providing diverse habitats for plants.

We evaluated the feasibility of conservation and restoration of the coastal dune plant Linaria japonica Miq. in coastal regions of the Inland Sea of Japan, based on the results of belt-transect survey, planting experiments, and seed germination tests. In the study area, the remaining L. japonica populations were found in the dwarf shrub zone dominated by Vitex rotundifolia. These L. japonica populations were exposed to a high risk of being eliminated by natural disturbances such as storm surge because of substantially reduced habitats. Most of the L. japonica seedlings planted in autumn regenerated their above-ground stems by the next year irrespective of planting habitats, while those planted in spring or summer rarely regenerated their above-ground stems, suggesting that the suitable planting season is from autumn to winter. The germination tests performed under different temperature conditions showed that, after L. japonica seeds are dispersed in autumn, their dormancy is broken during winter, and germination occurs in the next spring. These indicate that L. japonica seedlings can be obtained by sowing their seeds from autumn to winter. No significant light requirement of the non-dormant seeds for germination was noted, implying that burying L. japonica seeds under shallow soil cover does not prevent their germination. The germination tests for the L. japonica seeds collected during different years confirmed that storing the seeds at a low temperature （4°C） after vacuum-packaging maintained their germinability for at least eight years. Seed storage, thus, is effective for the conservation of L. japonica and should be promoted in parallel with the preservation and restoration of their extant populations.