積雪中の融解水による藻類粒子の垂直移動

Le résumé fourni par la source

The red snow phenomenon called ‘Akashibo’is usually observed from May to June during melting snow time in Ozegahara mire in Japan. The striking red coloration was mainly caused by the reddish-brown spherical particles with the diameter of about 10μm that are the spores of a green alga,Hemitoma sp.covered with iron oxide. These spores are enriched at the ground surface below the snow at the beginning,and their enrichment shifts to the upper layer as snow melting proceeds. It was thought that this shift is generated by movements of the spores from the lower layer to the upper layer. To test this possibility,we put acryl tubes containing snow with the spores at the bottom part on the mire at several different sites. Vertical movement of the spores toward the top part was observed only in the tubes which were put on the sites where snow melting water was present underneath the snow. These results support the idea that a flow of snow melting water toward the snow surface caused the movement of the spores from the lower layer to the upper layer.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.