Although Japanese black pine were the main species colonizing the coastal forest in Ehime Prefecture, Japanese black pine sawyer beetle Monochamus alternatus invasion has caused disappearance of the species. It is assumed that by choosing salt-tolerant species in broad-leaved forest, the protective function of coastal forests might be record. Native species along the shoreline on the outskirts of Matsuyarna City were surveyed; in addition, leaf-surface salt amount was measured.14 species of evergreen and 27 species of deciduous broad-leaved trees were identified. In the evergreen broad-leaved trees, salt amount deposited on a leaf surface was found higher than that in the deciduous broad-leaved ones. Moreover, deposited salt amount on the leaf surface was found higher in the winter than in autumn. The amount was remarkably higher in Euonymus japonicus (Thunb.) and Rhaphiolepis indica (L.) Lindl. var. umbellata(Thunb.) H. Ohashi compared with that of other tree species.

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In an increasing number of coastal forests, tree vigor is declining due to excessive moisture in soil on adjacent land, harmful insects, and area development, leading to concern over maintaining disaster prevention functions and scenic value. This research analyzed the state of growth and the groundwater environment in coastal forests of black pine spread over the Boso Peninsula in Chiba Prefecture using image processing of satellite data, and examined the usefulness of coastal forest surveys using satellite remote sensing.

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Field survey on the vertical and horizontal distribution of wind, the characteristics of grain size of shifting sand and the micro-topography were conducted to verify the effect of wind erosion control by vegetation (Carex kobomugi community) at sandy beech of Oiso, Kanagawa prefecture. The results are as follows ; (1) Wind speed on Carex kobomugi community was remarkably reduced because of the rise of roughness length by the increase of vegetative cover and the height of community, especially in summer. (2) The median value of sand particle size captured on the surface of community was 0.19 - 0.21 mm. The distribution of sand particle size showed the lower skewness and higher kurtosis than other particles on the surface of non-vegetation area. (3) The height of accumulated sand on the community was estimated at 9.1cm/year in the past three years. As the results mentioned above, it was assessed that the Carex kobomugi community showed the effect of wind erosion control at sandy beech.

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In coastal sand dunes, Robinia pseudo-acacia is growing to the detriment of Pinus thunbergii for several years. In plantations with a mix of Robinia pseudo-acacia and Pinus thunbergii, the fertilizations effect of Robinia pseudo-acacia appeared clearly under the condition of absence of defoliation. Robinia pseudo-acacia promotes the growth of Pinus thunbergii under the condition of defoliation deposition. According to the literature review, the chemical control of Robinia pseudo-acacia as for the standing tree is more effective than the stump chemical control.

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