maximum depth of 24 m and a reservoir storage
capacity of approximately 45=106 m3. The sampling
sites, determined by a random method
Scheaffer et al., 1987., are numbered from 1 to 8,
following the stream flow direction as indicated in
Fig. 1. Five sampling campaigns were carried out
in each site, on 24 May 1995, 30 June 1995, 28
July 1995, 5 October 1995 and 30 November 1995.