Bulletin of Glaciological Research
Online ISSN : 1884-8044
Print ISSN : 1345-3807
ISSN-L : 1345-3807
Temporal changes in snow algal abundance on surface snow in Tohkamachi, Japan(日本の十日町市における積雪表面の雪氷藻類濃度の季節変化)
ONUMA Yukihiko(大沼友貴彦)TAKEUCHI Nozomu(竹内望)TAKEUCHI Yukari(竹内由香里)
ジャーナル フリー

2016 年 34 巻 p. 21-31


Snow algae are cold-tolerant photosynthetic microbes growing on snow and ice. In order to investigate the factors affecting snow algal growth, the temporal changes in algal abundance on surface snow were studied over four winters in an experimental station in Niigata Prefecture, Japan, where seasonal snow is usually present from late December to early April. Snow algae appeared on the snow surface in February, and the initial algae were likely to be deposited on the snow by winds. The timing of the algal appearance varied among years, from early-February in 2011 to late-February in 2015, and is likely to be determined by a period of no snowfall and air temperatures above the melting point. Algal abundance generally increased until the disappearance of snow. The maximum algal concentration was found in 2011, which corresponds to the year when the period from algal appearance to the disappearance of snow was the longest (80days) among the four winters. The results suggest that snow algae keep growing unless snowfall occurs and air temperature drops to freezing point, and that the algal abundance is likely to be correlated with the duration of algal growth. The algal growth curve in 2011 could be reproduced by a Malthusian model with a growth rate of 0.22 d−1.

© 2016 公益社団法人 日本雪氷学会
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