In 1994, Eulalia speciosa (Poaceae) was found in a new locality in the southeastern Harima region, Hyogo Prefecture, western Japan. In this region, E. speciosa grows in Miscanthus-type dry grasslands formed on bald hills and on irrigation pond embankments. Phytosociological analysis revealed that these secondary grasslands were classified into one association and two communities. Eulalio speciosae-Miscanthetum sinensis, a newly recognized association peculiar to the southeastern Harima region, is characterized by the presence of a number of grassland species vulnerable in Japan, including E. speciosa, E. quadrinervis, Drosera peltata var. nipponica and Platycodon glandiflorum. The notable feature of the floristic composition of this association is a coexistence of tropical to subtropical Gramineous flora and cool-temperate herbaceous flora, both derived from regions in continental Asia with a relatively dry climate. Eulalio speciosae-Miscanthetum sinensis belongs to Arundinello-Miscanthion sinensis Suz.-Tok. et Abe 1959 ex Suganuma 1976, Miscanthetalia sinensis Miyawaki et Ohba 1970, Miscanthetea sinensis Miyawaki et Ohba 1970- Nearly all occurrencies of Eulalio-Miscanthetum sinensis are geologically restricted to areas with rhyolite pyroclastic rocks and lavas. The establishment of bald hills caused by fires and cutting, together with a dry climate and unique geology in the eastern Harima region, may be the main factors supporting the Eulalio speciosae-Miscanthetum sinensis in this region. Additionally, the existence of a large number of small grasslands on irrigation pond embankments seems to have provided suitable refugia for grassland species, through recent loss of grassland habitats caused by reforestation and progressive succession.

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Distribution and species composition of Alnus firma communities on floodplains were studied in mountainous zones of central Honshu, Japan. In this study, all stands were identified to Calamagrostio-Alnetum firmae Miyawaki Okuda & K. Fujiwara 1971. These stands were divided phytosociologically into two subassociations, subassociation of Salix sachalinensis, and typical subassociation, respectively. The subassociation of Salix sachalinensis was divided further into three variants, and the typical subassociation divided into two variants. The result of DCA analysis suggested that snowfall conditions and altitude were the main factors affecting differentiation of these vegetation units. The relationship between vegetation units and environment may be explained by differences of site stability, water-holding capacity of deposits and seasonal patterns of water discharge.

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A phytosociological survey was carried out on Quercus mongolica var. grosseserrata forest in Aomori Prefecture. Based on the floristic composition, the following single community and two associations were recognized. Quercus mongolica var. grosseserrata-Quercus dentata community is found on river-facing slopes or sea-facing slopes. Carpino-Quercetum grosseserratae is distributed only in the northern part of the peninsula. Lindero membranaceae-Quercetum mongolicae grosseserratae is distributed widely over the Tsugaru Peninsula. The floristic composition of these community units was compared with that of Quercus mongolica var. grosseserrata forests investigated by other researchers. The distribution pattern of the units is closely related to climatic conditions in winter, especially those of snow, humidity and air temperature.

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Vegetation recovery of drought deciduous forest (caatinga) growing under severe climatic stress and disturbances such as clear cutting and grazing was investigated in the semi-arid interior of northeastern Brazil. Floristic composition and plant architecture were compared among three stands of 4 years, 10 years and 20 years after abandonment to understand the changes that take place over time. In the 4 year-old stand, five woody species were found, while the number of Gaya aurea St. Hil, a herbaceous species, numbered 278 per 300 m^2. The 10 year-old stand was strongly influenced by grazing. Although G. aurea had increased in number, the plant size became smaller. In the 20 year-old stand, both the numter of trees and tree species greatly increased. This was because Bromelia laciniosa Mart, ex Schult. which covered the forest floor prevented the livestock from disturbing the vegetation. Tree species with a low wood density, which originally have a low tolerance of aridity, were also established. On the whole, the total aboveground biomass per 100^m2 increased from 33.03 kg in the 4 year-old stand to 769.10 kg in fresh weight in the 20 year-old stand.

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An evaluation of the natural landscape and environment was made on the basis of vegetation in the entire area of Otsu City (302.29 km^2), which is located in central Japan. With regard to natural landscape, eight landscape constituents from the actual vegetation map were classified and a map was prepared showing the distribution by degree of landscape dominance for each landscape constituent. The dominance of the landscape constituent was then classified into three types according to the standard of evaluation. After evaluating the landscape using mesh analysis, a landscape distribution map was prepared and analyzed. Concerning the natural environment, points of relative nature-degree were calculated for each mesh by using the nature-degree of vegetation and their spread. The points of relative nature-degree were then converted to classify the relative nature-degree. Finally, the distribution of relative nature-degree was plotted on a map superimposed with a mesh to evaluate relative nature-degree in Otsu City. Following this procedure, changes in relative nature-degree were studied by using the relative nature-degree distribution map prepared in 1979. To make an overall evaluation, the landscape distribution map and relative nature-degree distribution map were overlapped, and a map showing distribution of conservation areas was prepared by classifying each mesh into four categories according to their need of conservation. The four categories are : I. Area with highly natural vegetation ; II. Area with abundant natural landscape and environment ; III. Area where natural landscape and environment remain ; IV. Area with little natural landscape or environment. Finally, each evaluated area was described and an overall evaluation of Otsu City was made.

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The evaluation of grassland condition in semi-arid Inner Mongolia was discussed with changes of floristic composition under grazing. The species alternation in the stands were surveyed setting up with experimental field, in which varying numbers of sheep (0, 4, 8, 12, 16 or 20 per ha) were allowed to graze for 45 days per year. In the control non-grazing subplot, Aneurolepidium chinense (Trin.) Kitagawa and Artemisia frigida Wild, were dominant. While under the grazing conditions, component species were grouped into four types according to their response to grazing intensity. The importance value of Type I species, Aneurolepidium chinense and Stipa grandis P. Smirn, decreased with increased grazing pressure. The values of Type II species, Potentilla acaulis and Carex korshinskyi Kom. increased with increasing grazing pressure. Type III species appeared in heavily grazed stands, i.e. with 20 heads of sheep per ha, and included Chenopodium aristatum L. The importance value of Type IV species (such as Kochia prostrata L. Schrad. and Potentilla tanacetifolia) was not affected by grazing pressure. Abundance of Type II species with the high importance values indicates degradation of the grassland, and the presence of Type III species indicates that the stand is in danger of desertification.

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