PRESENCE AND DISTRIBUTION OF GENUS HELIANTHUS IN MONTEMARCELLO-MAGRA PARK (LIGURIA, NORTHERN ITALY)

Resumen

The growing spread of alien species requires their being monitored in order to
describe their diffusion and influence on local vegetation, particularly in
protected areas.
The aim of this study was the monitoring of genus Helianthus in the
Montemarcello-Magra park (northern Italy, Liguria, La Spezia province) both
from the point of view of its abundance and of the presence of different species.
Samples of genus Helianthus have been collected and identified in the whole
area of the park by using the analytic key to be found in Flora of North
America and by observing their distinctive anatomical features.
The analysis of the above mentioned features has allowed to come to the
conclusion that all the samples of genus Helianthus collected in the park belong
to the species H. tuberosus; its distribution is basically related to the
morphological features of the river banks and shows the tendency of the species
to colonize with a thick population flat river banks made of fine materials.