SEED DISPERSAL AND CHANGING SEED CHARACTERISTICS IN A PINUS-HALEPENSIS MILL FOREST AFTER FIRE

Seed density, seed colour and the number of seed damaged by birds were monitored for several months, after a late-spring fire, in two Aleppo pine (Pinus halepensis Miller) stands growing in South Italy. In one stand (S-1) the trees were completely burned ('charred') in the other one (S-2) the trees were only 'scorched', with a crown in part still a live after fire. 37% and 61% of seeds were released during the first m onth, respectively in S-1 and S-2. Damaged seeds accounted for 43% and 23% of seeds collected in the whole period, respectively in the charr ed and in the scorched stand. In both stands the percentage of empty s eeds increased in late-dispersed seed lots. The colour of released see ds changed with time: dark grey-brown seeds were released at first, wh ereas late-dispersed seeds showed a yellowish colour. The principal co mponent analysis performed on the categorical colour variables produce d a good discrimination between seed lots collected at different dates . Seed dispersal and the characteristics of released seeds have been d iscussed in relation to the post-fire recruitment process and, in part icular, to the possibility that the predation risk by granivorous bird s may be reduced by a mimicry effect of seeds to the underlying soil.