We investigated the impact of the sika deer (Cervus nippon) on plant species composition in montane and subalpine grasslands in the Chichibu-Tama-Kai area, Yatsugatake area, and Minami-Alps area, central Japan. In 2008, we resampled 61 releves which had been sampled in the 1980s and counted the number of fecal pellets of the sika deer in a given grassland. We found that the number of fecal pellets of the sika deer in 2008 was positively associated with the change from the 1980s to 2008 in the axis 1 score of detrended correspondence analysis of species composition; the utilization of grasslands by the sika deer was the greatest factor to determine the change in species composition. Moreover, sika deer positively utilized grasslands in regions with shallow snow cover in winter and inhabited areas away from buildings. Plant species richness changed from increase to decrease with increasing utilization by the sika deer. Increase of the impact of the sika deer was accompanied by retrogression of vegetation cover, which led to woody species invasions and an increase of cover in species tolerant to grazing.

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Carex livida (Wahlenb.) Willd. (livid sedge) is a perennial herb of the family Cyperaceae that is mainly distributed across North America and northern Europe. It is phytogeographically classified as a North American element. In the Far East, its distribution extends to Kamchatka, Kuriles, Sakhalin, Hokkaido, southeastern Siberia, and northern areas of the Korean Peninsula. In Japan, it is only found in the mires of Mt. Taisetsu (central Hokkaido) and Sarufutsu River (northern Hokkaido). Because of this disjunctive distribution, C. livida is considered a relict species from the glacial period. As C. livida favors the circumpolar area, and its distribution in Hokkaido represents the southernmost locality, studying the vegetation and environmental factors that affect C. livida growth in the mires will provide a key to understanding the phytogeographical characteristics of other boreal and arctic plants in northern Japan. The aims of this study are (1) to clarify the phytosociological position of the mire vegetation of Sarufutsu where C. livida grows and (2) to examine the factors common to the mires where C. livida grows across the world. The vegetation and microtopography were surveyed at three mires in the central part of Sarufutsu River Mire. Vegetation was recorded using phytosociological methodology. Microtopography was measured at two areas along lines running in the direction of the slope. Vegetation survey classified the areas as one hollow (Schlenke) community (S1) and three hummock (Bult) communities (S2, S3, and S4). After comparing with the vegetation of mountainous and lowland mires in Hokkaido and Ozegahara Mire and Aizu-tashiroyama Mire in Honshu, it is suggested that the typical subcommunity of S1 (S1-1) corresponded to the hollow vegetation Scheuchzerio-Rhynchosporetum albae. The other subcommunity of S1 (S1-2) and the hummock herbaceous communities (S2 and S3) belong to the intermediate (bog-fen transition) mire Carici-Moliniopsietum japonicae, because Moliniopsis japonica was dominant, and the character and differential species of Carici-Moliniopsietum japonicae and Moliniopsietalia japonicae occurred in a large part of the study area. Carex livida mainly appeared in the hollow community. The microtopographical pattern wherein the kermis and strings were alternately arranged parallel to the contour lines of the sloping mire (called a "Kermi-Schlenke complex") was observed in the C. livida growing mires. In North America and northern Europe, C. livida grows in patterned fen, and the microtopography of this survey area was also regarded as a small patterned fen. Therefore, it is suggested that C. livida grows in and around the hollows in the mires with patterned topography.

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Alien herb Coreopsis lanceolata often invades gravelly floodplain vegetation in Japan. The purposes of the present study were to clarify whether the soil texture types (i.e., gravelly, sandy, loamy and clayey types) affect the C. lanceolata invasions, and to detect the riparian endemic vegetation vulnerable to the invasions. On the gravel bars along the lower reaches of the Mibu River in Nagano Prefecture, central Japan, we surveyed the floodplain vegetation on each soil texture type using 164 quadrats consisting of 2m×2m plots. Coreopsis lanceolata cover on gravelly type was significantly lower than that on the other types. Coreopsis lanceolata cover tended to become higher from gravelly type to clayey type, indicating that gravelly type is less preferable for C. lanceolata than the other types. Negative correlations between the cover of C. lanceolata and total riparian endemic plants were observed on the finer-textured soil types, particularly loamy type, but not on gravelly type. Therefore, the endemic vegetation on loamy type mainly composed of Potentilla chinensis and Artemisia capillaris were considered to be vulnerable to the invasion impacts of C. lanceolata. The differences in influences of C. lanceolata on riparian endemics among soil texture types may be due to the differences in the dominance of this species among the soil texture types. Soil texture type is one of the factors affecting the invasion status of C. lanceolata on the gravelly floodplains, and endemic vegetation on finer-textured soil types such as loamy type will be endangered by the invasions.

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We investigated the effects of land management on species composition of plants and nectar flowers, butterflies in a semi-natural grassland at the foot of Mt. Fuji in central Japan. The study area included five site types with different vegetation structures and management regimes: (1) firebreaks where grass was mowed and removed, (2) Larix kaempferi plantation areas where grass was mowed alone, (3) unpaved roads with mowed banks, (4) abandoned grassland, and (5) scrub forest. In these sites, the largest number of annual plant species was found in the firebreaks, while woody plant species were more abundant in the plantations and the road areas. The smallest number of perennial plant species was found in the scrub. A two-way indicator species analysis divided the species composition of plants and nectar flowers into the scrub and the other sites, and secondarily, the firebreaks and the mowed areas, the road areas, and the abandoned grassland. The flowering season of indicator species of nectar flowers was July for the firebreaks, and August and September for the other sites. On the other hand, butterfly species composition in the firebreaks differed from all the other sites, and the indicator species in the firebreaks appeared in July, suggesting that butterfly species composition is affected by flowering season of nectar plants in this grassland. Moreover, the shrub species in the scrub were host plants for the larvae of certain butterfly species. These results indicate that butterfly diversity can be maintained by the diverse management regimes and vegetation structures in grasslands.

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