Effect of wind speed on loss of water from Nostoc flagelliforme colonies

The effects of wind speed on loss of water from N. flagelliforme colonies were investigated indoors in an attempt to assess its ecological significance in field. Wind enhanced the process of waterloss; the half-time of desiccation at wind speeds of 2.0 and 3.4 m s-1 was, respectively, shortened to one-third and one-fifth at 20°C and, to one-sixth and one-eighth at 27°C that of still air. Photosynthetic efficiency was not affected before the wet alga lost about 50% water.