著者
Kazuhiro SUZUKI Akiko IKEDA Kaori ADACHI Daniel DUNKLEY Etsuko NIU Takenori KATO Shinobu MORI Noriyuki FUJII
出版者
The Japan Academy
雑誌
Proceedings of the Japan Academy, Series B (ISSN:03862208)
巻号頁・発行日
vol.78, no.5, pp.111-116, 2002 (Released:2006-10-17)
参考文献数
15
被引用文献数
1

The Kamimura River, an upper tributary of the Yahagi River, flows through steep valleys in the mountainous Kamiyahagi area of Gifu Prefecture. The Tokai Gou flood of September 11-12, 2000 destroyed embankments along the river, and exposed sedimentary layers at Umi that are typical of a lacustrine depositional setting. This confirms the existence of a paleo-lake from which the name Umi originated. The lake was formed as the result of a huge landslide that dammed up the Kamimura River. To determine when the landslide occurred, radiocarbon (14C) ages of trees buried in lacustrine sediments were determined using accelerator mass spectrometry (AMS). The 14C ages are 300±25, 340±25, 345±25 and 380±25 BP for the outermost rings of tree trunks, which include bark, and a single age of 620±25 BP. Calibrated ages of (1637), (1520, 1590, 1624), (1517, 1597, 1619) and (1482) cal AD within a range of 1455-1643 cal AD are consistent with a landslide triggered by the Tensho Earthquake of January 18, 1586, which had an estimated magnitude of 8.2-8.3 and an epicenter in Ise Bay.
著者
TAKASHI YAMASAKI KEICHI OZEKI NORIYUKI FUJII MARI TAKEHARA MASASHI YOKOGAWA SHINGO KANEKO YUJI ISAGI
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.63, no.3, pp.107-120, 2013-04-05 (Released:2017-03-21)
参考文献数
73

Silene kiusiana (Caryophyllaceae) is an endangered perennial herb of semi-natural grasslands in Japan and Korea. To elucidate the genetic status of S. kiusiana in the Aso region, Kyushu, Japan, in which relatively large populations still remain, we analyzed the genetics of seven populations of S. kiusiana using five novel microsatellite markers. Each population of S, kiusiana has maintained relatively high genetic diversity (mean H_E = 0.791 and mean N_A =12.0). In addition, the values of pairwise F_<ST> indicating the degree of genetic differentiation among populations were significantly larger than zero between all pairs of populations, although the degrees of difference were small. The semi-natural grasslands in the Aso region have decreased in size over the past several decades, and thus habitat fragmentation may have caused genetic differentiation among populations of S. kiusiana. Although the populations of S. kiusiana have maintained relatively high genetic diversity, the genetic dynamics of S. kiusiana populations should be continuously monitored.
著者
Noriyuki Fujii Satoshi Takasawa Masashi Yokogawa Takashi Yamasaki Kensuke Harada Shingo Kaneko Yuji Isagi
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.67, no.2, pp.69-82, 2016 (Released:2016-12-20)

Veronicastrum sibiricum var. zuccarinii (Plantaginaceae) is an endangered perennial herb native to semi-natural grasslands in southern Korea and Kyushu, Japan. To elucidate the genetic status of V. sibiricum var. zuccarinii in the Aso region of Kyushu, in which relatively large populations still remain, we analyzed seven populations using five novel microsatellite markers. Each population of V. sibiricum var. zuccarinii has a maintained moderate level of genetic diversity (mean H E = 0.596, mean N A = 5.6, and mean AR = 4.7). Pairwise F ST indicated significant genetic differentiation between all population pairs (0.065−0.309). The semi-natural grasslands in the Aso region have decreased in area over the past decades. Thus, habitat fragmentation may be causing genetic differentiation among populations of V. sibiricum var. zuccarinii. Although the populations of this variety have maintained a moderate degree of genetic diversity, the dynamics of gene flow among them should be continuously monitored.