Based on DNA haplotype and morphology analyses, 3 separate species of Conocephalum conicum s. lat. and C. salebrosum had been recognized in Japan and Taiwan by Akiyama and Odrzykoski (2020), and are described here. Morphological features and patterns of distributional areas for the 4 species, including 3 new taxa, C. orientalis H. Akiyama, C. purpureorubrum H. Akiyama, and C. toyotae H. Akiyama (formerly recognized as C. conicum J, F, and R types, respectively) as well as pan-boreal C. salebrosum are described in detail.

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Changes in species composition of secondary summer-green forests along altitudinal gradient (40- 500 m) were examined in northern Hyogo Prefecture, Japan. Thirty-five forest stands were investigated. The species composition of the stands was analyzed using the phytosociological tabulation method. The results showed that the stands were divided into two types (A and B). Major dominant trees of type A and type B were Quercus serrata and Fagus crenata, respectively. The first-axis score of the detrended correspondence analysis ordination for the stands was highly correlated with values of the warmth index (WI) and the coldness index (CI), suggesting that the differences in species composition between the two stand types were primarily caused by air temperature conditions. Type A stands tended to be replaced by type B stands at approximately 300 m in altitude. This altitude was similar to the altitude at which natural evergreen broad-leaved forests were replaced by natural summer-green forests. The values of WI and CI at an altitude of 300 m were estimated to be 95 ℃ . month and -10 ℃ . month, respectively.

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The coastal area of the southern part of Hyogo prefecture, central Japan, has been undergoing tectonic uplift, induced mainly by the Rokko-Awaji and the Osakawan fault systems. To investigate the activities of these fault systems, we estimated the degree of crustal movements by comparing the elevations of sea-level highstand obtained from diatom fossil assemblages. We analyzed marine sediment layers of Marine Isotope Stage (MIS) 11 from terrestrial section at Mt. Takatsukayama, west of Mt. Rokko, and borehole core samples from Ishiyagawa, south of Mt. Rokko. Data were compared with published diatom records of borehole cores from Maya and Higashinada, south of Mt. Rokko. Diatom flora of Takatsukayama section showed environmental changes of marine transgression, with a horizon of sea-level highstand that most probably corresponds with MIS11.3, which was observed in Maya and Higashinada cores as highest sea-level period during MIS11. Differences in the elevation of those highstands between Takatsukayama section, and Maya and Higashinada cores were 338.9 m and 318.0 m, respectively, reflecting the fault activities since MIS 11. Their displacement rate was calculated as approximately 0.8 m/kyr. Diatom flora of Ishiyagawa core had no clear signal of the highstand, but displacement of as much as 110 m and 90 m was estimated comparing with Maya and Higashinada cores, respectively.

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More than 20 Chibanian tephra layers have been deposited on the higher terrace surface (Odamaki surface) along the Ara River in the Chichibu Basin. The grain and heavy mineral compositions and refractive indices of orthopyroxene and amphibole phenocrysts were analyzed in 17 samples from the OD1 (lowest) to Tama 128 (uppermost) tephras, to re-examine previous work on tephra correlation. OD1 exhibited petrographic features different from those reported in previous studies and was correlated to Kap-5 tephra in the southern Kanto region. Four biotite-rich volcanic ashes denoted OD6, OD9, OD11, and OD15, were correlated robustly with A1Pm to A4Pm of the Omachi APm tephras, respectively. However, no tephra layer in the basin could be correlated with Yt-hop tephra at the eastern foot of the Yatsugatake Volcano Group. The zircon fission-track (FT) dates of OD2 and OD6 were determined to be 510 ± 160 and 350 ± 70 ka (1σ error each), respectively; a more precise FT age of 356 ± 29 ka was obtained for OD6. All FT dates obtained using the same procedures and instruments revealed A1Pm to have a weighted mean age of 375 ± 21 ka. The estimated eruptive ages of OD2 and OD6 suggest that the Odamaki surface was formed between 500 and 600 ka.

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[in Japanese]

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Twenty seven percent of Japan is covered by plantation forests of evergreen conifers. Studies on forestry in Japan have emphasized forest productivity, while biodiversity conservation has not been well studied. The present study tried to find the effects of thinning on undergrowth and pollination in a Japanese cedar plantation. Thinning improved the light condition of the forest floor. SDR (Summed Dominance Ratio) of the undergrowth in the thinned cedar forest was 1.7 times greater than that in the cedar forest without thinning, and 4.5 times greater in the second year. Pioneer shrubs and large forbs typically growing in open habitats greatly increased by thinning. Thinning also increased insectpollinated flowers and pollinator visits, which were quantitatively similar to those in a deciduous broadleaved forest. In contrast, no pollination was observed in the cedar forest without thinning. This study suggests that biodiversity is recovered by thinning the Japanese cedar plantation forest.

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A living pseudoscorpion (Garypus japonicus Beier, 1952) was collected on August 28, 2020 from Shimono-zaki Cape along the western coast of the Shimokita Peninsula in Aomori Prefecture, northeastern Japan. The sampling location was located approximately 110 m above sea level at the sea cliff crest, which is the highest recorded habitat in Japan until now. The occurrence of pseudoscorpion at Shimono-zaki Cape as observed in the present study and its occurrence records with detailed topographic data are well investigated. The habitat of pseudoscorpion is mainly supratidal zone and its higher sea cliffs ranging from several meters to ten and several meters high, and in a few cases, reaching to several tens of meters to over 100 meters high along sea cliff. In addition, it is the important factor for its inhabiting environment that sea cliff is made up consolidated rock mass with open fractures.

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Phenological observations were performed monthly for 20 coastal plant species between July 2018 and March 2020 in coastal areas of the Harima-nada and Suo-nada Seas, located in the Setouchi region, western Japan. According to their habitats, the coastal plant species observed were classified into three types: the salt marsh type (Triglochin asiatica, Juncus gracillimus, Carex scabrifolia, Fimbristylis sieboldii, Phacelurus latifolius, Zoysia sinica var. nipponica, Limonium tetragonum, Atriplex patens, Bassia littorea, Suaeda malacosperma, Suaeda maritima subsp. asiatica, Artemisia fukudo, Tripolium pannonicum, Hibiscus hamabo), the rocky coast type (Euphorbia jolkinii, Dianthus japonicus, Chrysanthemum japonense, Peucedanum japonicum var. japonicum), and the beach-dune type (Polygonum polyneuron, Suaeda glauca). The time and duration of leafing, flowering, and seed dispersion were summarized for each species.

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We investigated mammalian and avian fauna in university forest of the Ishinomaki Senshu University, Miyagi Prefecture, using sensor cameras. We set the cameras inside the university forest and recorded the animals for one year (from June 2020 to June 2021). During the study period, 23 animal species (12 mammals and 11 birds) including Japanese serow (Capricornis crispus), which is listed in the Red List of Miyagi Prefecture, were recorded. Several movies recorded family or couple animals, which implied their reproduction. Sika deer (Cervus nippon), red foxes (Vulpes vulpes), raccoon dogs (Nyctereutes procyonoides) and domestic cats (Felis catus) were frequently recorded and bird species were less recorded. Six out of 12 mammalian species were recorded in all seasons, while others were not recorded in several seasons. Time zones when the movies of animals were taken (represent active time of target species) was similar to other study sites. We need to pay a special attention to density of sika deer in the university forest because recent studies have reported their negative impact on the vegetation and soil through grazing.

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