The status of tree seedlings and population changes before and after midsummer were investigated in coastal forests damaged by pine wilt disease. Although most seedlings propagated from seeds that fell from the upper and middle layers of the trees, some seedlings on the forest floor differed from the dominant species in the upper and middle forest layers. The seeds of these species were reported to have been dispersed by birds from trees in the surrounding area. The population changes before and after midsummer could be divided into two groups: those with post-midsummer survival rates of 45% or more, such as Celtis sinensis and Euonymus japonicus, and those with survival rates of 20% or less, such as Ligustrum japonicum and Pittosporum tobira.

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Shizuoka Prefecture built tide seawalls along the coast of Enshu-nada to protect cities from tsunamis. Pinus thunbergii, and three broadleaved tree species Rhaphiolepis indica, Pittosporum tobira, and Euonymus japonicus were planted at the slopes and the seaside sand flats. It is a new approach to use mountain soil on the seawalls and plant these broadleaved trees by the coast. In this paper, we report on the survival conditions which are combined with measurements of the volume water content (VWC%), soil temperature and electrical conductivities. Data were collected over a period of four years. The survival rates of broadleaved trees were completely different between mountain soil and sand. The findings imply that dryness stress on the sand limits the survival of these broadleaved trees. Specifically, these trees died due to two weeks of sunny weather in hot summer on the sand.

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Changes in sandy beach of Noto Sotoura as a source of blowing sand due to beach expansion caused by the 2024 Noto Peninsula Earthquake were investigated. The width, length and area of sandy beaches were measured by Google Earth images provided before the earthquake and aerial photographs taken by the Geospatial Information Authority of Japan in January 2024 after the earthquake. As a result, it was estimated that the total area of sandy beaches in 74 locations was approximately 167ha after the earthquake, doubling the pre-earthquake area. In addition, a field survey was conducted on three sandy beaches in Wajima City where a significant increase in area was observed after the earthquake. As a result of examining the risk of wind-blown sand damage, it was assumed that blowing sand increases on these beaches during strong northerly or southwest winds, and that the risk of wind-blown sand damage will increase in the future where there are no wind and sand protection facilities such as coastal forest or where coastal forests have disappeared or deteriorated due to pine dieback. Therefore, it was considered important to conduct on-site monitoring of coastal changes in situ and interviews with local residents

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