1,720,965 research outputs found
Geomorphological map of the Biferno river valley floor system (Molise, Southern Italy)
No full textA 1:20,000-scale geomorphologic map of the valley floor system of the Biferno River (Molise
Region, Italy) is presented in this paper. Map analysis and aerial photography interpretation, in
addition to field surveys, have allowed digital mapping of fluvial landforms and associated coastal, slope and anthropogenic forms which have characterised the valley floor in different periods. Comparative multi-temporal analysis performed in a GIS for the time-period 1869–
2010 allowed the reconstruction of spatial-temporal relationships between most of the mapped
landforms and acquisition of quantitative data on channel adjustments. The geomorphologic
map provides an overall large-scale view of major channel adjustments over the past 150
years as well as the current morphological setting and dynamics of the Biferno valley floor. It
provides a basic map for land planning policy with the observed distribution of active
geomorphic processes to be used for landslide and erosion susceptibility assessment and the
data obtained on channel adjustments essential in investigating land cover change over the
same period. As the Biferno valley floor system is characteristic of major river systems in
Central-Southern Italy, the reconstructed framework of valley floor transformations turns out
to be useful when assessing a representative channel evolution model and potential scenarios
concerning near future dynamics of similar river systems
Channel adjustments in a Mediterranean river over the last 150 years in the context of anthropic and natural controls
No full textvolutionary trajectories and related control factors of the Fortore River (southern Italy) are analyzed over a 150-
year period as to assess channel modifications. A multitemporal GIS analysis of topographic maps and aerial photographs
together with topographic and geomorphological field surveys were performed. Attention was focused
on the impact caused by human disturbance, above all the presence of the Occhito damat only 40 kmupstreamof
the Fortore mouth (central Adriatic coast).
Results show that channel adjustments occurred in three distinct phases and were primarily driven by human
disturbance that diversely affected reaches located upstream and downstream of the dam. Fromthe last decades
of the nineteenth century to the 1950s (phase 1), channel widening prevailed along upstream reaches whilst
narrowing along downstream reaches. Major channel adjustments occurred from the 1950s until the end of
the 1990s (phase 2), especially channel narrowing of up to 81% in upstream reaches and 98% in downstream
reaches. Narrowingwas accompanied by channel-bed lowering of 1 to 5mand by pattern changes in prevalence
from multithread to largely prevailing single-thread channel configurations. In-channel mining, channel works,
and hydraulic interventions are considered key driving factors of observed channel adjustments. The closure of
the Occhito dam in 1966 had significant and permanent effects on downstream reaches through overall discharge
regulation and permanent sediment trapping as also proved by the progressive retreat of the Fortore
river mouth area. From 2000 to 2015 (phase 3), a substantial trend inversion was observed with overall channel
widening and partial aggradation of upstream reaches and total stabilization of downstream reaches. As
highlighted by an integrated multitemporal analysis of recent channel changes and flood events, the latter
have played an important role in channel recovery of upstream reaches.
Comparison between the Fortore River and other rivers in southern Italy has allowed us to ascertain that the reconstructed
evolutionary trajectories are quite similar and that control factors are essentially the same. In particular,
it confirms the role of major hydraulic structures as to the amount of channel adjustments of downstream reaches and the ensuing scarce to nil potential to channel recovery of regulated reaches
River channel adjustment in Southern Italy over the past 150 years and implications for channel recovery
No full textMulti-temporal GIS analysis of topographic maps and aerial photographs along with topographic and geomorphological
surveys are used to assess evolutionary trends and key control factors of channel adjustments for
five major rivers in southern Italy (the Trigno, Biferno, Volturno, Sinni and Crati rivers) to support assessment
of channel recovery and river restoration.
Three distinct phases of channel adjustment are identified over the past 150 years primarily driven by human disturbances.
Firstly, slight channel widening dominated from the last decades of the nineteenth century to the
1950s. Secondly, from the 1950s to the end of the 1990s, altered sediment fluxes induced by in-channel mining
and channel works brought aboutmoderate to very intense incision (up to 6–7m) accompanied by strong channel
narrowing (up to 96%) and changes in channel configuration from multi-threaded to single-threaded patterns.
Thirdly, the period from around 2000 to 2015 has been characterized by channel stabilization and local
widening. Evolutionary trajectories of the rivers studied are quite similar to those reconstructed for other Italian
rivers, particularly regarding the second phase of channel adjustments and ongoing transitions towards channel
recovery in somereaches. Analyses of river dynamics, recovery potential and connectivity with sediment sources
of the study reaches, framed in their catchment context, can be used as part of awider interdisciplinary approach
that views effective river restoration alongside sustainable and risk-reduced river management
Environmental changes in the Boiano intramontane basin (Molise, Italy) since the times of ancient Bovianum (IVth century BC).
No full textThe ancient Samnitic and Roman towns of Bovianum, located at the base of the northern slope of the Matese Mountains and partially extending within one of the most depressed sectors of the Boiano intramontane basin, were strongly influenced by historical palaeoenvironmental changes mainly due to climatic and man-induced variations and subordinately to the effects of historical seismicity. These changes influenced the evolution in time of the urban settlement layout extensions, which shifted alternatively towards the Matese slope and its piedmont area and the plain. In particular the Samnitic-Roman Municipium (IV century B.C.-I century A.C.) was located mainly within the piedmont area and only partially within the plain, while other smaller settlements were founded at the top of the palaeosurfaces of Mt. Crocella and Civita. From the I to the IV century A.C., the Roman Colonia expanded both towards the plain and the slope, thanks to the reclamation of the most depressed sectors of the plain, as well as to slope terracing and buildings, respectively. After the IV century A.C. and up until the XIX-XX century AD, the plain sector was gradually abandoned, while the urban areas were mainly concentrated at the top of the Civita paleosurface and within the piedmont area. Within the last two centuries the plain was newly occupied, conversely the Civita settlement was gradually abandoned. With the intent of investigating the main palaeoenvironmental changes and their causes, an integrated multidisciplinary analysis of the morpho-stratigraphical and historical-archaeological data was carried out. Facies analyses of two core successions, retrieved from the central area of the modern village of Boiano, and a critical review of archaeostratigraphical records of older archaeological excavations, allowed for the identification of 10 archaeostratigraphical units. The sedimentary succession intercepted by the core located at the base of the piedmont area base of the Matese slope was made up of alternating layers of paleosols, debris cone deposits and man-induced fills, the succession coming from the core located in the plain sector, instead, by alternating layers of paleosols and fluvial marshy-deposits. The tephro-stratigraphic data allowed to chronologically constrain the uppermost 7 to 9 m thick portion of the Boiano filling (named Boiano upper fill) to the Later Upper Pleistocene-Holocene. Archaeological data from older excavations and the archaeological remains included in the core successions then allowed to date most of the aggradation and waterlogging phases recognized in the piedmont area and plain sector, respectively. At least three debris cone deposition phases could be recognized which are chronologically constrained prior to the IV century A.C., between the IV century A.C. and the Middle Age and between the XVI and XIX centuries AD, respectively, and can be most likely correlated with the well documented periods of climatic deterioration known as the Iron Age, the Dark Age (IV-IX centuries AD) and the Little Ice Age (XVI-XIX centuries AD), respectively. Likewise debris deposition, as well as waterlogging affected the plain mainly during the above mentioned periods and can be certainly -at least partially -attributed to the mentioned periods of climate deterioration characterized by increased rainfalls and consequent rising of the ground water level. Waterlogging events, however but could have been favored also by tectonic subsidence, caused by the earthquakes which affected the Boiano area during the III-II century B.C. and in 853, 1456 and 1805 A
Evoluzione geomorfologica di lungo termine del settore molisano dell'Appennino meridionale
No full text
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
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