Vegetation analysis and field survey on soil infiltration capacity have been carried out in the site of Ehime and Kagawa prefectural boundary forest fire in February 1985. Four investigations were carried out until 1998, 13 years after the forest fire. In the vegetation analysis, there were an increase of the number of the species and a change from pioneer species into high shade tolerance in each plot. Therefore the quantitative and qualitative change of the vegetation was confirmed. The infiltration capacity of soil surface lowered after the fire, and there was a tendency of recovery. However, there was a difference of recovery by slope azimuth and slope position. As a result, though the vegetation recovers right after the fire by the sprouting, soil recovery was slower than that of the vegetation. This may be due to the fact that the soil is formed by humification of litters and other factors.

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To characterize the root strength properties of red pine tree by elapsed years after forest fire, we measured and analyzed the tensile force and strength of the roots. The mean tensile force was a decrease of 51 % and 71 % compared with the original root tensile force within 2 and 3 years after forest fire, respectively. 67% of the tensile strength of original root was lost within 2 years after forest fire and 74% was gone within 3 years. The rate of tensile force and strength deteriorations in larger roots was increased more than that of finer roots by root diameter classes and elapsed years after forest fire.

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A field survey was conducted on the topography and the soil property for the development of coastal vegetation at Shonan beach, Kanagawa prefecture. 6 patterns of topography were recognized and those patterns were in relation to the position of sand fence, and the relief to the level of cycling road. Water contents, pH and Electrical conductivity (EC) were analyzed and some features were found on the vertical and horizontal distribution of their concentration. Further study would be necessary to make clear the relationship among the cation and anion in the sand, the position of sand fence, dynamism of underground water for the establishment of the coastal vegetation.

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