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Phenological and floristic diversity in agroecosystems: some cases in Emilia-Romagna
No full textThe aim of this study was to investigate the plant biodiversity of semi- and sub-natural vegetation in the intensively cropped plain area of the Emilia-Romagna region. These coenoses (hedgerows between crops, herb margins and strips, ditch banks), where the soil is not exploited, represent valuable reservoirs of biodiversity which are under continuous threat.
With the aim of evaluating the contribution of these communities to the biodiversity of agrecosystems, phytosociological and symphenological surveys were conducted in three sites: A) in the lowlands of Emilia (Modena-Reggio Emilia), B) in the area at the foot of the hills between Emilia and Romagna (Bologna), and C) in the Romagna coastal area (Ravenna).
Vegetation analyses show both qualitative and quantitative differences among the three areas: the greatest variety in vegetation types and habitats is observed in areas A and B (6-7 different vegetation types), while area C appears to be more monotonous (with a mere 3 types).
The results of floristic analyses suggest that the abundance of species (based on the number of species observed in 30 phytosociological relevés for each area), depends to a greater extent on micro-environmental factors and site management than on the territorial context: areas A and B, characterised by a fair variety of habitats, display a wider floristic diversity (approx. 180 species from over 50 families) than area C (approx. 120 species from 32 families). The flora is composed mainly of synanthropic species, with high percentages of annual plants (between 30% and 45%) and sub cosmopolitan plants; however, it is also worth noting the presence of several nemoral and hydrophilic species, hidden away in hedges and along ditches, as well as rare plants (about 10% of the total).
Phenological patterns show relationships with the life forms and the synecological features of the plants. The analyses of symphenograms show generally bimodal trends of blooming intensity (varying with coenosis, site and year): the first peak corresponds mostly to the onset of anthesis in woody species and annual grasses, while the second one, taking place between late spring and summer, is due to the perennial grasses.
The relationships between plants and animals were also investigated, in collaboration with several experts. Significant correlations were observed between certain parameters of Lepidoptera (number of species and abundance) and the plant diversity, as well as the abundance of the grass layer (Puppi et al. 2008).
Summing up, in order to preserve and increase biodiversity in the agricultural ecosystems, we have to maintain a network of sub-natural and semi-natural structures. Moreover, these should have a high variety of structural as well as ecological features
Diversità vegetale in agroecosistemi della pianura emiliana
No full textPer valutare l’importanza degli spazi subnaturali, in un tratto della pianura emiliana tra Novi (MO) e Rolo (RE), sono state studiate banchine erbose, argini di canali, siepi arbustive e arboree in 9 siti (diversi tra loro per vegetazione), ubicati in tre aree (diversa tra loro per complessità ecologica). I rilievi sulla vegetazione sono stati eseguiti con il metodo fitosociologico; inoltre sono stati rilevati i seguenti parametri: complessità della rete di corridoi ecologici dell’area circostante il sito di rilievo (CA); complessità ecologico-vegetazionale del sito (CS); diversità floristica del sito (DS); complessità strutturale dei tipi di vegetazione (CV); diversità floristica dei tipi di vegetazione (DV)
Variazioni della diversità floristica in boschi collinari della provincia di Bologna
No full textViene 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
"Castanea sativa woods" in the Northern Apennines: a phytosociological analysis along ecological gradients
No full textCastanea sativa woods, one of the most widespread habitats of southern Europe, are included in the European Community Natura 2000 network within Sites of Community Importance (SCI). In the Northern Apennines, chestnut woods are mainly coppices derived from old chestnut orchards, and now abandoned. To describe the relationship between present chestnut structure and vegetation features, we analysed the plant diversity of chestnut woods by 143 phytosociological relevés within 6 SCIs. The gradient of diversity was identified by multivariate analysis (clustering and ordination) and related to other woods such mixed oak woods or lowest altitude Fagus sylvatica woods in order to evaluate the potential evolutionary pattern of present chestnut woods
Ruolo della flora e della vegetazione di siepi e prati per la conservazione della fauna negli agroecosistemi della pianura emiliana
No full textE' presentato uno studio floristico-vegetazionale svolto sulle siepi e le banchine erbose della campagna modenese-reggiana (Novi e Rolo). E' stata valutata a) la ricchezza e la vulnerabilità floristica (specie rare e uniloche), b) la complessità vegetazionale in termini di struttura e di ricchezza in tipi, c) la naturalità-artificialità della vegetazione. Sono state poi analizzate le correlazioni tra i parametri floristici, vegetazionali e territoriali (complessità dell'area), al fine di fornire indirizzi utili alla gestione degli spazi naturali di questi agroecosistemi
Castanea sativa woods in some SIC of the Bologna Province: an analysis along a gradient.
No full textCastanea sativa woods are one of the most widespread and typical habitats of the southern European mountain landscape and have both historical and agro-ecological value. Furthermore are considered an important habitat for biodiversity conservation point of view and are included in the European Community Natura 2000 network as the habitat “Castanea sativa-dominated forests and long-established plantations with semi-natural undergrowth” .
In the Bologna Province, chestnut woods are mainly coppices derived from old chestnut orchards. The biodiversity of chestnut coppices was examined by 200 phytosociological releves and gradient of biodiversity was analyzed by multivariate analysis (clustering and ordination). Releves were also compared with those of mixed oak woods to evaluate transitions of chestnut woods into mixed oak woods
Effetti di margine sulla diversità floristica nei boschi del basso Appennino bolognese
No full textAnalisi della biodiversità floristica dei principali tipi di bosco naturale o subnaturale presenti sulle colline a sud di Bologna, in relazione ai fattori ambientali ed antropici e con particolare riferimento all'effetto di margine
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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