Paola Ferrazzi & Monica Vercelli DISAFA UNIVERSITY OF TURIN ITALY

Transcription

1 Paola Ferrazzi & Monica Vercelli DISAFA UNIVERSITY OF TURIN ITALY 2nd Apiecoflora 6-7th November Rome, Italy

2 Alpine areas are particularly famous for the honey produced as they can guarantee a non-contaminated environment and very diverse floral origin. Several studies have been published on honey produced in the Alps, and in particular on those from Piedmont (Ferrazzi and Marletto, 1980, 1985; Ferrazzi and Gerlero, 1996, 2001; Ferrazzi et al. 1999) and Valle d'aosta (Ferrazzi, 1986, 2002; Adamo, 2003). There are also numerous studies on honey production in other Italian regions including Lombardy (Gianoncelli and Rossi, 2008), Venice (Ricciardelli d Albore, 1995), Trentino Alto Adige (Vorwohl, 1972), Friuli Venezia Giulia (Gazziola, 2002), and Switzerland (Maurizio, 1958).

3 The three Lanzo Valleys and four other neighboring valleys (Malone, Tesso, Ceronda, and Casternone) constitute an alpine area of the province of Turin (Piedmont, Northwest Italy) characterized by continental climate with frequent rainfalls. They extend from 300 m above sea level to 3,380 m for Rocciamelone, and measure km 2.

4 Migratory and sedentary beekeepers (150) produce kg of honey annually, depending on altitude, climate, and apiary management. In order to characterize and improve the local productions, the honeys of the Lanzo Valleys are analyzed in terms of floral origin using melissopalynological and sensorial analyses.

5 MATERIALS AND METHODS Surveys on bee flora of Lanzo Valleys were achieved during three years. At the same time beekeepers were contacted. Melissopalynological and sensorial analyses were carried out on 20 samples of honeys produced in Lanzo Valleys, according to Harmonized methods of melissopalynology (Apidologie, special issue 2004).

6 RESULTS The beekeeping management in Lanzo Valleys resulted very different

7 RESULTS The Lanzo Valleys are heavily wooded, with a high percentage of chestnut. In analyzed honeys, the constant presence of the Chestnut pollen has chestnut emerged, as this plant is widespread in the area, as well as by the presence of unifloral honeys. been detected, albeit in small percentages, even in honeys produced at high altitude, and was observed as pollution of honeycombs in productions by migratory beekeepers and because bees can fly to lower parts of the valleys to forage on this species.

8 Prunus (e.g. cherry) and Pyrus (Sorbus aria, S. aucuparia) pollen was present in almost all samples, sometimes reaching high percentages. A total of 85 pollen forms were found, which is less than most other alpine areas. The quantity of honeydew is poor.

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10 Considering the floral origin of the honeys, the majority are multifloral, but unifloral honeys from Tilia spp., Rhododendron ferrugineum, Acer pseudoplatanus, and Robinia pseudoacacia (in the lower areas) were also found. The contribution of linden is important, which gives rise to bifloral honeys with Castanea sativa.

11 In the rhododendron flower honeys there is a good percentage of blueberry.

12 The Lanzo Valleys are located, from a melissopalynological aspect, in alpine zones "devoid of Onobrychis", like other valleys in Piedmont (Sangone and Pellice Valleys), Valle d'aosta (Champorcher and Lys Valleys), and in Trentino-Alto Adige (Vorwohl, 1972). Only one honey sample produced in a high site, neighbouring Susa Valley, showed some sainfoin pollen.

13 The lower number of species useful to bees found in the surveys conducted in the Lanzo Valleys compared with other Alpine valleys, is reflected in the lower diversity of pollens found in honeys. We also recorded a decrease of flowerings, especially for some herbaceous species that often characterize some zones and their typical productions. The wild pollinators decline is strictly connected to the flora decrease, also in relation to the specificity of pollination, even giving to the competition for the resources.

14 These facts underline the important role of the honey bee, more flexible than many other pollinators and suitable for preserving biodiversity. In fact, the honey bee is more resistant to global warming and other issues, thanks to the beekeeping practices. The widespread presence of the honey bee in the Lanzo Valleys and other Alpine territories is essential for pollination, and therefore for the conservation of plant biodiversity in these areas, given the steady decline of wild bees (Biesmeijer et al., 2012; Winfree et al., 2010).

15 THANK YOU FOR YOUR ATTENTION! INFLUENZE DELL IMPATTO ANTROPICO SULLE RISORSE FLORISTICHE, FONTI DI SUSSISTENZA PER GLI APOIDEI DOMESTICI E SELVATICI, E RIFLESSI SULLE PRODUZIONI MELLIFERE Seminario Coevoluzione tra insetti e piante ed effetti dei cambiamenti climatici e della globalizzazione C.R.A. - Unità di ricerca di Apicoltura e Bachicoltura Bologna 17 febbraio 2012