Azolla-Anabaena as a Biofertilizer for Rice Paddy Fields in the Po Valley, a Temperate Rice Area in Northern Italy

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.

Period	Mean T ^∘C day	Mean T ^∘C night	Mean RH% day	Mean RH% night
22 Mar.–29 Mar.	11.7	7.8	71.1	78.4
30 Mar.–05 Apr.	10.4	7.4	71.4	84.2
06 Apr.–12 Apr.	12.0	8.9	64.5	79.1
13 Apr.–19 Apr.	12.0	10.1	76.1	84.1
20 Apr.–26 Apr.	18.0	14.3	56.5	67.3