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Phytolith and macroscopic charcoal in cumulative soils on the Soni Plateau, Central Japan, were evaluated to clarify the Holocene history of intentional fires and grassland development, and to compare the findings with those derived from pollen and charcoal records in sediments taken from a nearby mire in the previous study. Prior to ~1500 cal. BP, Bambusoid short-cell phytoliths and Pleioblastus-type and Bambusoideae-type bulliform cell phytoliths were abundant with scarce charcoal particles (<1000 particles/cm3). In contrast, since ~1500 cal. BP Andropogoneae-type bulliform cell phytoliths and Bilobate short-cell phytoliths were dominant with abundant charcoal particles (>1000 particles/cm3). Based on correlating these records with pollen and charcoal records in mire sediments, prior to ~1500 cal. BP, dwarf bamboo flourished on the forest floor under largely fire-free conditions, whereas since ~1500 cal. BP, grassland dominated by Japanese pampas grass has been sustained by periodic intentional burning that has continued until the present day.

Phytolith analysis was applied to clarify a vegetation history at stands on the Dorokawa Mire, northern Hokkaido. Phytolith assemblages from surface samples and Holocene deposits from the mire are used to clarify the stand-scale vegetation history, with special focus on the dynamics of Gramineae, which includes dwarf bamboo, and the establishment of stands on the mire. The phytolith records during the early Holocene (to cal BP) indicate the distribution of Pooideae dominated vegetation, which reflects the cool climate. (reed) dominated vegetation from the early to mid Holocene (to cal BP) suggests wet conditions like low-moor. The reed was replaced by dwarf bamboo at cal BP, although the distribution of dwarf bamboo was scattered. At cal BP, dwarf bamboo increased abruptly and has been sustained to the present. Also, Pinaceae type phytoliths began to occur continuously at cal BP. Taking into account the relationship between modern vegetation and modern phytolith assemblages on the mire, the occurrence of the Pinaceae type phytoliths from the sediment samples indicates the existence of in the study sites. On the basis of these results, stands with dense undergrowth of dwarf bamboo would have been established in the study sites on the mire by cal BP at least. canic ash and gravel", "sand dunes", "serpentinite widespread on the mountain slopes of the area. In general, forests are established on dominated stands with dense specific sites. Tatewaki () classified undergrowth of dwarf bamboo are established forests into six habitat types : "mire", "volon the Dorokawa Mire, which covers the drainage basin of the Dorokawa River in northern substrate", "conglomerate" and "remains of fire Hokkaido. On the other hand, mixed forests disturbance" types. According to the habitat composed of some conifers and hardwood trees types, the stands on the Dorokawa (etc.) are Mire are classified as a "mire" type.

Long-term response of respective grass types to variations in fire frequency in central Japan, inferred from phytolith and macrocharcoal records in cumulative soils deposited during the Holocene. Quaternary International. 527, 94-102.