1,720,971 research outputs found
Biodiversità delle piante e tutela degli ecosistemi: Imparare dal passato per progettare il futuro
No full textDurante la Preistoria, Neolitico ed Età del Bronzo sono i periodi di interesse chiave per studiare l’impatto dell’uomo sul territorio. Se durante il Neolitico l’attività e l’influenza antropica cominciano ad essere visibili, è con l’Età del Bronzo che se ne amplifica l’impatto, sebbene in entrambi i casi sia stato sempre possibile il ristabilirsi di un equilibro post-occupazionale dell’ambiente.
Obiettivo della presente tesi è quello di indagare questi due periodi di impatto antropico nella Preistoria per cercare di indagarne modalità, caratteristiche e conseguenze per l’ambiente naturale e per le comunità umane. L’area di studio scelta è il Nord Italia e in particolare sono stati scelti siti in Pianura Padana, nella pianura Friulana e nella Valle dell’Adige: Palù di Livenza, sito palafitticolo Tardo Neolitico e facente parte della lista UNESCO dei Patrimoni dell’Umanità in Friuli Venezia-Giulia; Gardolo di Mezzo, sito funerario e importante centro metallurgico risalente all’Età del Rame e del Bronzo in Trentino-Alto Adige; San Michele di Valestra, sito di altura associato alla civiltà terramaricola sull’Appennino Reggiano e Rovere di Caorso, il sito terramaricolo più occidentale, in provincia di Piacenza.
Gli obiettivi specifici di tale indagine sono stati la caratterizzazione della flora e della vegetazione delle aree di studio e il loro cambiamento nel periodo considerato per capirne modalità e cause, sia climatiche sia antropiche e cercando di caratterizzare le strategie di uso del suolo e sussistenza da parte delle popolazioni locali. A tal fine, in tutti i siti sono state campionate sequenze stratigrafiche verticali per effettuare analisi polliniche, il principale proxy applicato nella presente ricerca. A Palù di Livenza, due sequenze on-site sono state prelevate dal Settore 3 per un totale di 40 campioni con una cronologia Tardo Neolitica (ca. 6350-3600 anni BP); inoltre, un carotaggio off-site (di cui sono stati analizzati 21 campioni rappresentativi di una sequenza di circa 6 metri) è stato effettuato con una cronologia che parte dall’Ultimo Massimo Glaciale e che comprende anche i livelli Neolitici. A Gardolo di Mezzo, una sequenza di 39 campioni pollinici è stata prelevata da un’area funeraria dell’Età del Bronzo (ca. 3500-2900 anni BP). A San Michele di Valestra, 36 campioni pollinici sono stati campionati da una sequenza verticale su una parete rocciosa che rappresentano un intervallo cronologico dal Bronzo Recente fino al Bronzo Finale (ca. 3000-2900 anni BP). Infine, a Rovere di Caorso, 20 dei 49 campioni prelevati da una sequenza nel fossato occidentale della Terramara e risalenti al Bronzo Recente (ca. 3250-2860) sono stati analizzati.
Grazie alle analisi polliniche di dettaglio effettuate, associate anche all’analisi di altri palinomorfi non pollinici e dei microcarboni, è stato possibile studiare biodiversità e copertura vegetazionale di ciascun sito e i loro cambiamenti. L’analisi degli spettri pollinici ottenuti ha permesso in tutti i casi di caratterizzare la presenza e la composizione di aree boschive, di aree umide, di campi coltivati e/o dedicati alla pastorizia e, anche tramite il confronto con altre sequenze di riferimento per le aree di studio, sono state fatte inferenze sulle modalità di sfruttamento del territorio e la gestione delle risorse da parte delle popolazioni locali, nonché su eventuali cambiamenti a livello climatico che abbiano potuto influenzare le scelte culturali. In tutti i siti, è stata rilevata una forte influenza antropica nei territori occupati a confermare come sin dalla Preistoria le comunità umane abbiano scelto un punto di stanziamento idoneo alle loro esigenze e da quel momento ne abbiano iniziato lo sfruttamento per la propria sussistenza, influenzando il paesaggio circostante.During Prehistory, Neolithic and Bronze Age are key periods for studying human impacts on the territory. If during the Neolithic the anthropic activity and influence begin to be visible, it is with the Bronze Age that the impact is amplified, although in both cases it was always possible to re-establish a post-occupational environmental equilibrium.
The aim of this thesis is to investigate these two periods of anthropic impact in Prehistory in an attempt to investigate their modalities, characteristics and consequences for natural environment and human communities. The study area is Northern Italy, and in particular sites were chosen in the Po Plain, the Friuli Plain and the Adige Valley: Palù di Livenza, a Late Neolithic pile-dwelling site and part of the UNESCO World Heritage List in Friuli Venezia-Giulia; Gardolo di Mezzo, a funerary site and important metallurgical centre dating from the Copper and Bronze Ages in Trentino-Alto Adige; San Michele di Valestra, a mountain site associated with the Terramare civilisation in the Apennines of Reggio Emilia; and Rovere di Caorso, the westernmost Terramare, located in the province of Piacenza.
The specific objectives of this research were to characterise the flora and vegetation of the study areas and their changes during the period considered in order to understand their modalities and causes, whether climatic or anthropic, and to attempt at characterising land use and subsistence strategies by local populations. To do so, vertical stratigraphic sequences were sampled in all sites to perform pollen analyses, the main proxy applied in this research. At Palù di Livenza, two on-site sequences were sampled from Sector 3 for a total of 40 samples with a Late Neolithic chronology (c. 6350-3600 years BP); in addition, an off-site core (of which 21 samples representing a sequence of ca. 6 metres were analysed) was carried out with a chronology starting from the Last Glacial Maximum and including Neolithic levels. At Gardolo di Mezzo, a sequence of 39 pollen samples was taken from a Bronze Age burial area (c. 3500-2900 years BP). At San Michele di Valestra, 36 pollen samples were sampled from a vertical sequence on a rock surface representing a chronological interval from the Recent to the Final Bronze Age (c. 3000-2900 years BP). And finally, at Rovere di Caorso, 20 of 49 samples taken from a sequence in the western moat of the Terramara and dating from the Recent Bronze Age (c. 3250-2860) were analysed.
Thanks to the detailed pollen analyses performed, also associated with the analysis of other Non-Pollen Palynomorphs and microcharcoals, it was possible to study the biodiversity and vegetation cover of each site and their changes. The analysis of pollen spectra obtained made it possible, in all cases, to characterise the presence and composition of woods, wetlands, cultivated fields and/or fields dedicated to pastoralism, and, also through comparison with other reference sequences for the study areas, inferences were made on the methods of land use and resource management by the local populations, as well as on any changes in climate that might have influenced their choices. In all sites, a strong anthropogenic influence was detected in the occupied territories, confirming how, since prehistoric times, human communities chose a suitable settlement location for their needs, and from that moment on began to exploit it for their subsistence, influencing the surrounding landscape
Sophisticated land management in the Middle-Recent Bronze Age: palynologycal evidence from the Terramara Santa Rosa di Poviglio (northern Italy)
No full textThe integrated palynological and geoarchaeological study provides increasingly detailed knowledge of the subsistence
and productive economy of prehistoric cultures. The Terramara Santa Rosa di Poviglio Bronze Age site (Northern Italy) was characterised by a complex system of sylvo-agricultural economy and a multifunctional land use as happened
in most of prehistoric sites. The site consists of two dwelling areas - ‘Villaggio Piccolo’ (VP) and ‘Villaggio Grande’
(VG) - dating back to the Middle Bronze Age and to the Recent Bronze Age, respectively. During the exploration
of the hydraulic facilities of the site, a stratigraphic sequence 4 m deep was identified in the moat dividing the VP
and VG part of the settlements. The high-resolution VP/VG stratigraphic record provided a ten-year resolved pollen
stratigraphy that preserves evidence of environmental changes happened in the Po Plain during the Late Holocene.
Pedosedimentary features and biological records (aquatics pollen and algal remains) show that shallow water was permanent at the bottom of the moat at the beginning of the formation of the sequence, while the water level dropped
significantly during the last phase of existence of the settlement. Along the trajectory of the settlement, pollen curves
show significant trends and short oscillations representing coppicing and crop rotation practices. In the last phases
of site occupation, an increased climatic aridity and intensive land use may have had a combined negative effect at
the expense of plant cover. Cereal cultivation continued during the late Recent Bronze, but the main traits of the
landscape became pasturelands. The study of the final part of the infilling of the moat indicates that the regeneration
of the forest did not occur immediately after the abandonment of the village (dated at ca. 3200 years BP), but in the
early Middle Ages, when the area turned into a swamp
Rare species in past pollen records and herbarium specimens: Linnaea borealis L. lived in north-eastern lowlands in Italy during the Neolithic
Full text linkThis paper emphasises the role of detailed pollen identification in past records and the importance of historical herbaria in palaeoecological research on plant distribution over the last millennia. Palynological analyses of a sediment core, covering approximately the last 10,000 years, from the wetland surrounding the UNESCO archaeological site of Palù di Livenza, in the lowlands of Friuli-Venezia Giulia, revealed the unexpected presence of Linnaea borealis during the Mid-Holocene (about 8600–4200 cal yr BP) in north-eastern Italy. This species is a rare small suffruticose plant which grows among mosses in conifer and mixed forests, between 1200 and 2100 m a.s.l. In Italy, due to the restricted climatic requirements, its current distribution is limited to a few high-mountain stands and to four northern regions (Val d'Aosta, Piedmont, Trentino-Alto Adige, Lombardy). Pollen grains of L. borealis found in past samples from the Friuli-Venezia Giulia region raised interest because this species was not recorded so far in this region either at present or in the past. To confirm the identification, a morphological study was carried out on pollen from flowers collected from University Herbaria (Florence and Pisa). Dried pollen extracted from anthers was acetolysed and observed with a Digital Optical Microscope. Polar axis, equatorial axis, exine thickness, equatorial diameters, mesocolpium, and distance among apices of colpi were measured in current and past pollen grains. Morphological analysis confirms the presence of L. borealis in the sedimentary archive studied, adding an important insight into the knowledge of past and present biodiversity of the area
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
