Table 2: Temperatures and RH% during the course of the experiment, from Mar 22nd to Apr. 28th 2002. Increase of Azolla biomass is somewhat dependent on air humidity as at less than 60% of relative humidity, the fern becomes dehydrated and fragile. During the experiment, the RH% dipped below this critical level for a brief period.

PeriodMean T dayMean T nightMean RH% dayMean RH% night

22 Mar.–29 Mar.11.77.871.178.4
30 Mar.–05 Apr.10.47.471.484.2
06 Apr.–12 Apr.12.08.964.579.1
13 Apr.–19 Apr.12.010.176.184.1
20 Apr.–26 Apr.18.014.356.567.3