I

ANNO 4 Numero 2

Penelope Zanolli, Renzo Barbattini, Franco Frilli, Federica Gazziola [1]

Honey analysis: melliferous sources and environmental pollution in the city of Udine (Italy)

[1] Dip. di biologia applicata alla difesa delle piante, Università di Udine, Udine, Italia

Corresponding author: penelope.zanolli@libero.it

Honeybees are important environmental indicators as well as pollinators and honey producers. The ethological and biological characteristics of the honeybee (meticulous exploration of the area surrounding the hive, colonies with high numbers of individuals, concentration of polluted substances in hive products) are such that a a 7 km2 area around the hive can be monitored. To evaluate the presence of bee plants and the pollution level in the city of Udine (NE-Italy), melissopalinological and heavy metal analyses were performed on six honey samples collected in the year 2003, four from the city and two from the suburban area. Field observations were carried out to determine floral species present in the considered territory: more than 300 species were identified.

Enumeration of honey pollens was performed on two slides obtained from the same honey sample. The concentration of heavy metals was measured by atomic absorption spectrophotometry with electrotermic atomization (GFAAS). Rosaceae, Compositae, Leguminosae and Labiatae are were found to be the most represented families in the city. “Phanerophyte” and “Hemicryptophyte” are the dominant Raunkier life forms while within “corotypes” subcosmopolitan is the most important, followed by exotic (mainly ornamental plants).

Most of the identified nectariferous species flower in June, the rest in May and July. Melissopalinological analysis showed pollens of Trifolium repens gr. and Rubus f. in all samples but also of Brassica f. and Aster f.: these species grow on roadsides or in city gardens and parks. The occurrence of these pollens in honey samples with a high levels of heavy metals can indicate that the nectar has been collected in anthropic areas.

The results of the melissopalinological analyses and the floral survey give a clear indication of the flora fingerprint that can be expected in honey produced in the city of Udine and its immediate surroundings.

Contamination of the honey from environmental pollution, evaluated in terms of presence of heavy metals, was greater in honey produced near main and busy roads, but no significant differences (P>0.05) were observed between urban and suburban honey samples.