Introduction

In the Mediterranean region, several studies have been devoted to the distribution of pollen in coastal marine areas (Rossignol, 1961; Koreneva, 1971; Rossignol & Pastouret, 1971; Belfiore et al., 1981; Brun, 1983). Other studies have tried to understand the pollen rain in mountain areas where peat bogs are excellent pollen recorders (Reille, 1975; Beaulieu, 1977). However, little is known about how much of the pollen produced in high and middle altitudes is transported to the area of sedimentation near the shoreline, and how it is transported.

The region of Calvi in Corsica is typical of Mediterranean climatic conditions, where mountains rise to 2000 m a short distance (20 km) from the coast, with rather humid climate at the top (near 2000 mm precipitation, concentrated during the cold season; Simi, 1964), and rather dry climate (near 700 mm precipitation) near the coast. Autumn, winter, or spring high rainfall on the top and on steep slopes (Fig. 5.1) produces huge and violent floods (Guilcher, 1979), which carry large stones that accumulate on the narrow coastal plain and which also deliver fine material to the sea. During the dry season (summer) the rivers are at minimum flow and often vanish in the coarse sediments of the coastal plain. Two small rivers enter the sea near Calvi, the Fiume Secco and the Ficarella (Fig. 5.1).