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Un dipinto di natura morta della prima metà del Seicento, appartenente alla Fondazione Zani, di autore ignoto, è già stato oggetto di uno studio dettagliato da parte degli autori sulle specie botaniche. In questo contributo si pone l'attenzione in particolare su alcune specie del dipinto di interesse storico-artistico o rilevanti ai fini dell’attribuzione. La presenza di alcune specie raramente raffigurate, come Hyacinthus orientalis "caule folioso" e Phalaroides arundinacea, presenti in quadri di Giacomo Recco, fanno ipotizzare l'attribuzione del dipinto all'ambiente artistico napoletano ed in particolare all'ambito di Giacomo Recco. Ipotesi che pare confermata anche dalla presenza della rara Primula palinuri e dalla presenza sul mercato antiquario di un'opera di composizione molto simile attribuita al figlio Giuseppe Recco.

The study highlights the changes occurred in several stands of Hyperico richeri-Vaccinietum communities of the high Emilian Apennines after 30 years after the first phytosociological and phenological surveys. In 2012 the same types of surveys were repeated in the original stands, with the aim to detect any change in vegetation structure as well as in species composition and behaviour. The study has pointed out significant changes in all the vegetation stands over the last 30 years. The following trends are displayed in the stands analysed: A) a general decrease of species richness per stand; B) a slight increase of the shrubs/herbs cover ratio, with a significant spreading of Juniperus communis and of Vaccinium uliginosum, sometimes coupled with a reduction of V. myrtillus cover; C) a reduction of Orophytes and of many species belonging to the classes Caricetea curvulae and Nardo Callunetea; D) a xero-thermic trend of plant communities composition (index species analysis). It is noteworthy that many of the declining species flower in the dryest and hottest period of the year (July-August). The results seems to indicate that the changes in vegetation features are due only partly to human causes (lighter grazing) and more widely to climatic stress.

The study highlights the changes occurred in 10 homogeneous stands both of Vaccinium and Nardus communities of the Emilian Apennines after 30 years from the first surveys. The stands were sampled by phytosociological and phenological methods in the years 1981-1984 (Puppi, Zanotti & Speranza, 1994 - Phenological studies on Vaccinium and Nardus communities. Fitosociologia) near the mount “Corno alle Scale” (BO). In that time, the locations of the stands were exactly recorded (CRT map 1:10000) and documented by series of photos. In 2011 and 2012 the original sites were found again and the same types of surveys were repeated, with the aim to detect any change and to investigate its possible causes. Main results are here summarized. Community’s structure has become more complex: in particular, Juniperus nana cover is significantly increased; moreover, among Vaccinium species, V.gaultheriodes is going to prevail on V. myrtillus, probably damaged by the shortening of the snow cover duration. In general, species richness is lower than 30 years ago. Many herbaceous species are rarefied or disappeared: in particular Caricetea curvulae and Nardo Callunetea species become reduced in abundance and number. On the other side, only few new species appeared ( e.g. Veratrum album, Maianthemum bifolium, etc.). Changes in vegetation features seem to be due in part to natural dynamics (lighter grazing) and in part to climatic stress. In fact, the climate of the area has become warmer and drier (less snow and less rainfalls in winter, spring and summer) over the last 2 decades, as deduced from data of Marletto et al., 2010 (Atlante idroclimatico dell’Emilia-Romagna 1961-2008. ARPA). Aridity periods (P/T

Phenological scales used in the past were not standardized: in different countries different methods were followed and these are often still in use today: for example Italian Botanists usually make the phenological observations by means of the GFI key, adopted in 1993 by the Italian Phenological Gardens, or by Marcello’s Key. The comparability of data collected with different methods is a serious problem, so, in the last 20 years the scientific community has directed significant efforts toward the standardization of sampling methods and phenological scales: in Europe, the BBCH scale (Meier, 1997) has been generally adopted. Although the BBCH and GFI scales have different structures, several stages are corresponding. We present a method for the conversion between BBCH and GFI scales, based on the numerical relationship between the codes of the respective stages: in the reproductive cycle the relation is well approximated by a sigmoid function, while in the leaf development, by a linear function. The presented method also allows the fractional values of the stages to be converted (e.g. the average value of a population). Keywords: Phenological scales, BBCH, GFI, growth stages, flowering, leafing

Il volume contiene una sintesi delle serie di vegetazione d'Italia, analizzate in relazione ai fattori climatici e litomorfologici.

In Europe, in the last thirty years, the onset of spring has advanced (Estrella et al. 2009 Clim Res. 39). However the phenological shifts vary from one country to another and long time series are scanty in Southern Europe (Peňuelas et. al. 2002, Glob. Change Biol.; Črepinšek et Kajfež 2003, Ann.Ser.Hist.Nat.13): for this reason we analyzed the data on leafing of some woody species recorded during the last 3 decades (1977-2009) in the city of Bologna (Emilia-Romagna, Northern Italy) and in several hillside stations in the neighbourhood of the town. As BGS index, the average day of “first leaf unfolding” (GFI=V4, BBCH=11) of a group of common woody species was chosen: the BGS days were analysed in relation with time and temperature changes. The BGS happens on average at the end of March. The species observed display a negative trend along the period (about 2 days of advance per decade) and the BGS days show a significant correlation with the mean temperature of the period January-March (about 3 and a half days of earlier start per degree of increasing temperature). Since an increase in winter temperatures has been predicted in the Emilia-Romagna region in the next decades (Tomozeiu et al. 2007, Theor. Appl. Climatol. 90), the growing season in our region is probably going to extend. Phenological spatial patterns of the neighbourhood of the city are also analysed: greening generally starts on southfacing hills between 100 and 300 m asl.

Phenological behaviour of some common woody species have been recorded during about 3 decades (1975-2008) in the city centre of Bologna (Emilia-Romagna, Northern Italy) and in several hillside stations in the neighbourhood of the town. The dates of start and full flowering have been analysed in relation with time and temperature changes. Both winter (hazel) and spring flowerings (ash tree and chestnut tree) show slight negative trends (an advance of 2-4 days per decade) along the period. In the last 40 years of the 20th century, in Emilia-Romagna region, the winter and spring temperatures have shown an increase of 0,2- 0,4°C per decade (Tomozeiu et al. 2006, Clim. Res. 31) and a further increase of about 0,2- 0,3°C per decade has been predicted, by means of a downscaling technique, in the 21th century (Tomozeiu el al. 2007, Theor. Appl. Climatol. 90). Since the flowering days of the observed species show significant correlations with the mean temperature of the preceding months (3-5 days of earlier start per degree of increasing temperature), in the future earlier flowerings can be expected to occur.

An overview of the oldest phenological data collected in Italy, for scientific purposes, with scientific criteria and methods, is presented. Following the example of Linnaeus, in the 19th century various Italian botanists such as Ottaviano Targioni, Teodoro Caruel, Alessandro Serpieri and Giuseppe Bertoloni, went on to create phenological calendars, with notes on the local climate and agricultural work. Besides, the earliest phenological network on both cultivated and wild plants was organized by Almerico Da Schio and Domenico Lampertico at the end of XIX century (1876-1884) in 16 localities of the Veneto and Emilia regions. The European Phenological Network founded by Hoffman and Ihne (1882) was joined by botanists working in the Italian Alps, like Wilhelm Pfaff, who was responsible for a very long series (1886-1933) of phenological records at Bolzano.

We report the results of the processing of a long-term series of phenological data regarding the anthesic phenophases of Corylus avellana (Hazel): the data were recorded in the city centre (University Botanical Garden) of Bologna (Italy) over a period of approximately 3 decades (from 1981 to 2008)

STORIA DEL'ORTO BOTANICO E DESCRIZIONE DEI SINGOLI SETTORI DELL'ORTO BOTANICO CON DESCRIZIONE DELLE SPECIE PRESENTI

Viene presentato uno studio sulla ricchezza floristica di diversi tipi di vegetazione forestale situati nella fascia collinare dell'Appennino Bolognese. Lo studio si basa sia su rilievi fitosociologici eseguiti ad hoc con l'intento di evidenziare le variazioni della biodiversità in rapporto al substrato, al microclima e all'azione antropica, sia su transetti effettuati dal bordo forestale verso l’interno del bosco, per evidenziare l’effetto di margine.

L’oggetto del presente contributo riguarda l’analisi del comportamento fenologico di alcune specie indicatrici erbacee e legnose, nell’inverno 2006/7, che ha avuto un andamento termo-pluviometrico anomalo con alte temperature e bassa piovosità. Sono state confrontate le date di comparsa della piena fioritura delle specie guida in due parchi di Bologna di cui erano disponibili lunghe serie di dati fenologici pregressi.

Il Fiume Panaro presenta notevoli criticità correlate allo sfruttamento antropico del territorio. Questo studio si pone di analizzare lo stato e la quantità dei mesohabitat a disposizione per le comunità fluviali utilizzando le ortofoto Quickbird 2003 ad alta risoluzione. Il processo di fotointerpretazione delle ortofoto, condotto alla scala di 1:3000, permette di caratterizzare differenti habitat. con il controllo di sopralluoghi mirati in campo. La successiva digitalizzazione degli habitat fornisce i dati per effettuare stime numeriche in modo speditivo, al fine di evidenziare le relazioni spaziali tra le artificializzazioni rilevate e la conseguente banalizzazione degli ambienti fluviali

Nel territorio della provincia di Bologna il nostro gruppo di ricerca ha raccolto dati fenologici con una certa regolarità a partire dal 1977 fino ad oggi. Dagli anni ’80 in particolare, è stata svolta una intensa attività di rilevamento in campo su piante della flora spontanea, indirizzata soprattutto al monitoraggio fenologico territoriale, che ha portato alla produzione di mappe fenologiche e fenoclimatiche a varia scala. Recentemente la serie storica dei dati fenologici è stata inserita in una banca dati, che ha permesso di analizzare trends pluriennali in relazione alle variazioni climatiche in atto.

La ricerca riguarda la caratterizzazione bioclimatica di un territorio orograficamente complesso, realizzata in base al comportamento fenologico della flora spontanea. Viene presentato un esempio relativo al territorio bolognese, basato sul confronto tra mappe fenologiche realizzate mediante un modello feno-topografico e mappe climatiche costrite in base al modello delle sommatorie termiche.