Progress of the Cryptomeria japonica pollen front in 2021 was monitored by tracking the first day of pollen release using a Durham sampler at 81 sites and an IS Rotary sampler at eight sites, distributed from Kyushu to Hokkaido in Japan. The results from the Durham sampler showed that by late January, the pollen front had reached the northern parts of western Chugoku on the Sea of Japan, and parts of Tokai that faced the Pacific Ocean. By early February, the front had passed through all of Kyushu and reached parts of Chugoku, parts of Shikoku that faced the Seto Inland Sea, and parts of southern Kinki, Tokai and southern Kanto that faced the Pacific Ocean. By mid-February, the front had passed through central Chugoku, northern Shikoku, almost all of Kinki and Hokuriku, and parts of Tokai, Chubu, southern Kanto and southern Tohoku. By late February, the front had reached the central to northern areas of Tohoku and, unexpectedly, parts of northern Chugoku that faced the Sea of Japan. By early to mid-March, the front had reached the northern parts of Tohoku, although the front had already reached some parts of this area in late February. The front finally reached the eastern and central parts of Hokkaido by late March.
抄録全体を表示