A classification and evaluation of landscape were carried out symphytosociologically in the suburb of a metropolitan area in the Miura Peninsula, Kanagawa Prefecture, central Japan. By means of a grid method that combined mesh analysis with sigmareleve based on an actual vegetation map (1 : 50000), the landscape of the study area was classified into the following four community complexes as landscape units : Chrysanthemo - Miscantho = Euonymo - Pittosporo geosigmataxon (A) ; Polysticho - Perseo = Castanopsio geosigmataxon(B); Rubo - Aralio = Daphno - Querco geosigmataxon (C) ; Non-vegetation landscape area (D). For the evaluation of the natural grade of the landscape by principal component analysis, the relative vegetation naturalness (RVN), the relative diversity index of natural vegetation (RDNV), and the mean population density were calculated for each community complex. Consequently, the natural grades of landscape were high in A and B, but low in C and D. Based on the natural grade of landscape and the similarity of location as calculated by several geological data, the potential natural landscapes that could be substituted for C and D were presumed to be B and A, respectively. The method applied in this study will be an effective measure for planning of environmental conservation.

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The species composition and density of soil seed banks were investigated at burned and unburned Cryptomeria japonica forest. The majority of seeds in the seed bank at the unburned site were C. japonica. The number of species and density of seed bank in the first autumn after the fire were smaller than at the unburned site. The soil seed bank in the first year was characterized by numerous seeds of Commelina communis and no seeds of C. japonica. It is suggested that the dormancy of buried seeds of C. communis was broken by fire stimulation, and mature plants produced many seeds. Disappearance of C. japonica seeds in the soil seemed to be caused by short seed longevity, and lack of newly dispersed seeds from mother trees due to above-ground vegetation burning. The soil seed bank tended to recover from fire impact in the second year after the fire. The number of species on the seed bank in the second year was larger than the first year. Density of C. communis seeds, which increased just after the fire, decreased in the second year. In contrast, the seeds of C. japonica, Alunus hirsuta and so on, which disappeared after the fire, reappeared. In the second year, the seed bank consisted of both seeds produced by regenerated plants after the fire and seeds dispersed from the neighboring undisturbed area.

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We compared the stand structure and regenerative conditions of Persea thunbergii on a mixed and a pure P. thunbergii forest on two neighboring islands of northeastern Japan along the Pacific Ocean. The relative dominance of P. thunbergii at the basal area exceeded 0.9 in a pure stand on Tsubaki Island. The height distribution of trees was bimodal ; one peak was the upper layer occupied by P. thunbergii, and the other was the lower layer occupied by Camellia japonica. There were 662 (/ha) saplings (height≧1.3m and DBH<5cm) of P. thunbergii, 85% of which originated from sprouts. In a mixed stand on Yakei Island, three evergreen broad-leaved trees, P. thunbergii, Daphniphyllum macropodum and Ilex integra, were the major canopy species. The relative dominance of these three species at the basal area was 0.45 (P. thunbergii}, 0.19 (D. macropodum}, and 0.16 (I. integra}. The mixed stand had a continuous tree-height distribution. There were many saplings (1055/ha) of P. thunbergii, and most of which were raised from seeds. Significantly more light was available in the mixed stand than in the pure stand, although there was no difference in the gap rate between the two stands. This difference in the light environment may arise from the differences in stand stratification. Thus, the heterogeneity of stratification may promote recruitment into saplings in a mixed forest, in contrast to a pure forest.

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The relationship between the species composition of the soil seed bank and the above-ground vegetation was investigated in a semi-natural Phragmites australis community maintained by winter mowing. All species contained in the seed bank were component species of above-ground vegetation. However, there was no seed reserve of Phragmites australis, Arundinella hirta, Miscanthus sacchariflorus and so on in the soil, in spite of these species being components of the above-ground vegetation. Most of the seeds of the transient seed bank in this community seemed to have become germinable as the result of low temperature during winter. Seeds of the persistent seed bank also seemed to have broken their dormancy and to become germinable due to the post-disturbance environment resulting from winter mowing. We consider that the persistence of buried seeds has been decreased by periodical artificial disturbance. The species composition of the seed bank was, therefore, similar to that of the vegetation.

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The coastal mantle communities, which are dominated by stress-tolerant scrambling pioneers, were studied using the Ztirich-Montpellier School's method in South Korea. The order Rosetalia rugosae of northern type and the class Viticetea rotundifoliae of southern type, which are totally dominated by Rosa rugosa and Vitex rotundifolia, respectively, are the representatives of the coastal mantle vegetation in South Korea. The coastal mantle communities in South Korea are composed of 2 communities and 3 associations : the Rosa rugosa community, the Vitex rotundifolia community, the Linario-Viticetum, the Roso-Viticetum and the Imperato-Viticetum. All the associations in South Korea are subordinated to the Japanese syntaxa and hierarchical system. The coastal mantle communities are characterized both syntaxonomically and synecologically, and their syngeographical distributions in South Korea are shown on the maps.

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