With the rapid increase of sika deer （Cervus nippon） population in Japan, its distribution is expected to expand to the mire. Although herbivores have a major impact on the various ecosystems, little is known about their effects on mire vegetation. In this paper, we assessed the effect of sika deer on the bog plant communities in Kushiro Mire, northern Japan. First, we determined the distributions of deer trails and their feeding marks on bog species to identify whether grazing, trampling or digging mainly effected bog vegetation. Next, we conducted a vegetation survey and compared the vegetation among the plots grouped by trampled area, including plots from an earlier survey, to determine the effects of trampling. By comparing the lack of feeding marks on bog plants and the significant increase in the length of deer trails from 2004 to 2010 （400-800%）, we determined that the effect of trampling by sika deer was higher than that of grazing. Trampling remarkably reduced the vegetation cover, but it had no influence on the species number. The effects of trampling differed between growth forms. Bryophyte and dwarf shrubs were more reduced than graminoids. However, annual plants （Eriocaulon） increased their cover in hollow community, whereas Sphagnum papillosum emerged frequently in hummock community. Overall, trampling had negative effects on bog microtopography as well as vegetation, and it could take a long time to restore the bog vegetation.

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Carex livida（ Wahlenb.） Willd. （livid sedge） is mainly distributed across North America and northern Europe. In the Far East, its southernmost localities are the northern part of the Korean Peninsula and Hokkaido. In Japan, it is observed in Sarufutsu-River Mire （northern Hokkaido）, Mts. Taisetsu （central Hokkaido）, and Shiretoko Peninsula（ eastern Hokkaido）. Most severe environmental conditions were observed in Mts. Taisetsu. Carex livida favors the circumpolar area, and its distribution in Hokkaido represents the southernmost locality; therefore, studying the vegetation and environmental factors that affect C. livida growth in the mires will provide keys to understand the phytogeographical characteristics of other boreal and arctic plants in northern Japan. The aim of this study was to clarify the phytosociological position and environmental factors of the mire vegetation in Mts. Taisetsu where C. livida grows. Vegetation and microtopography were surveyed at Hiragadake Nanpo Mire and Chubetsu-numa Mire in the central part of Mts. Taisetsu. Vegetation was recorded using the phytosociological methodology, and microtopography was measured along the direction of the slope. Vegetation was classified as a hollow community and a hummock community in both mires. After comparing the vegetation of mountainous communities in Mts. Taisetsu and other areas in Hokkaido, it was suggested that the hummock community in Hiragadake Nanpo Mire corresponded to alpine wind-exposed-dwarf-shrub vegetations and that in Chubetsu-numa Mire corresponded to alpine snow patch vegetations. The hollow communities in both mire corresponded to Caricetum limosae. The microtopographical pattern called a “KermiSchlenke complex” was observed in two mires, and this pattern was common with other C. livida growing mires in Hokkaido. The difference between the height of hummocks （Kermi） and hollows （Schlenke） was evident in Hiragadake Nanpo Mire, whereas that of Kermis and Schlenkes in Chubetsu-numa Mire was indistinct. It was suggested that the environmental conditions and vegetations similar with permafrost area kept the C. livida’s growing in Hiragadake Nanpo Mire and Chubetsu-numa Mire.

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Species composition was compared among areas of abandoned cropland on forest steppe and typical steppe to assess long term effects of cultivation on vegetation in Mongolia. Using phytosociological methods, vegetation surveys were conducted in forest steppe regions on seven stands in cropland idled for 2 years, six stands in cropland abandoned for 25 years, and five stands in lightly grazed pasture. In typical steppe regions, surveys were conducted on 17 stands in cropland idled for 2 years, five stands in cropland abandoned for 21 years, and eight stands in lightly grazed pasture. The surveys were conducted in 2010 and 2011. Non-metric multidimensional scaling and a permutational multivariate analysis of variance were used to clarify the differences in the vegetation recovery process between regions. Using existing phytosociological studies, whether character species is re-established after abandonment in each region was assessed. Consequently, it was demonstrated that species compositional dissimilarity between abandoned cropland and lightly grazed pasture was larger in typical steppe than in forest steppe. The character species were re-established in the abandoned cropland in the forest steppe, whereas they were less in the typical steppe. Cultivation in the typical steppe appeared to have more serious effects on vegetation recovery.

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This study aimed to evaluate the current status of the Mongolian steppe region using a modified stand quality index (mSQI). The mSQI was calculated by summing the multiplied value of the extended summed dominance ratio (ES_n) and indicator species scores (s-score). ES_n was calculated as a relative value using the maximum values in all of the communities surveyed or study periods. The s-score was derived from an octave transformation (base-2 logarithmic transformation) of the ES_n, and calculated from the ratio of ES_n value between grazed and ungrazed stands. For example, s-scores >1.0 indicate that a species is decreased by grazing, and s-scores <1.0 indicate that a species is increased by grazing. In addition, the palatability of plants to livestock was reflected in the indicator s-scores. Species known to be unpalatable were evaluated as having a low s-score in this study. Conventional evaluation methods indicated that the deteriorated land was improved by an increase in the plant biomass even if the abundance of plants of low utility value increased. The mSQI is a new evaluation method that can determine qualitative species characteristics and can be used to identify steppe with high utility value for local nomads.

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To quantify the species composition of epiphytic woody plant communities in the canopy, we climbed trees using ropes and directly measured the epiphytic woody plant communities on a Cryptomeria japonica tree that regenerated after harvesting in Edo Period and a remnant tree left standing in a mixed coniferbroadleaf forest on Yakushima Island. We found only 4 species and 8 individuals on the regenerated tree, whereas we found 12 species and 391 individuals on the remnant tree. In the remnant tree, Sorbus commixta occurred in the upper canopy, while Vaccinium yakishimense occurred in the mid to lower canopy and Rhododendron tashiroi occurred on the lower stem, reflecting vertical stratification among species. Based on their size distribution, we inferred that the dominant epiphytes are regenerating in the canopy. Our results suggest that remnant trees function as refugia for species that do not occur on the ground and that retention of large, old trees after harvesting contributes to maintaining biodiversity of the forest.

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