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Changes in land use in the last two centuries in the Po lowlands (northern Italy)
No full textChanges in land use represent, after fossil-fuel combustion, the greatest cause of greenhousegases
emission into the atmosphere. Coastal wetlands, also referred as coastal blue carbon
ecosystems (e.g. salt marshes, mangrove forests, seagrass meadows, swamps), represent one of
the most powerful C sinks among the Earth’s ecosystems, being capable to sequester organic
carbon (OC) at rates ca. 30-50 times higher than terrestrial forests. Historically, land reclamation
for agriculture, farming and urban expansion, severely impacted coastal wetlands, causing their
loss and degradation. Wetlands drainage lead to the oxidation of organic matter previously stored
under anaerobic conditions and the release of CO2 into the atmosphere. Only recently the critical
role of blue carbon ecosystems in climate-change mitigation has been recognised, highlighting the
importance of protecting and studying these precious environments.
In this work, changes in land use in the last two centuries are reconstructed through comparison
with historical maps. At the beginning of the 19th century Napoleon Bonaparte requested the
development of high-quality maps of occupied territories. Among these, the so-called ‘Carta del
Ferrarese’ (CdF), completed between 1812 and 1814, is composed of 38 sheets and represents, to
a scale of 1:15.000, 240.000 hectares of the Po lowlands, roughly corresponding to the present-day
Ferrara district. The CdF, archived at the Kriegsarchiv in Vienna, is an extraordinary example
among historical maps for its high quality and accuracy, which constitute a two-centuries-old
reliable paleo-landscape picture.
Within the Historical Land Use Change research project, leaded by the Emilia-Romagna Statistical
and GIS Service, the CdF was scanned, accurately georeferenced and orthorectified, showing a
surprising generalized match with recent maps. More than 31.000 polygons were digitized in a GIS
environment and interpreted on the basis of the European Corine Land Cover codes, properly
modified for the land uses at the time.
Comparison with the recent land use analysis, carried out in 2014, highlights changes in land use,
mainly related to land reclamation. Salt marshes and swamps, originally extended for 100.000
hectares, were reduced of about 85%, starting from 1861. Major phases of land reclamation
occurred in 1870s and 1960s. Geochemical analyses on shallow samples (depth < 50 cm), depict
OC content of artificially drained soils < 5% of the total volume. Soil texture testifies to the almost
complete mineralization of OC after reclamation. Only recently drained soils show higher OC
content, in the range of 10-15%
Satellite-Derived Shoreline Analysis of the Emilia-Romagna Coast (Italy) from 1984 to 2023
No full textTemporal and spatial analysis of relative sea-level changes across the Emilia-Romagna coastal plain (northern Adriatic Sea)
Full text linkSea-level rise coupled with subsidence, namely relative sea level, currently represents the greatest threat to low-lying coastal areas worldwide, leading to a constant increase in flooding risks and shoreline erosion. The Emilia-Romagna coastal plain in northern Italy, facing the Adriatic Sea, is highly urbanized and critically important to the national economy. However, the entire area is prone to high flooding risks due to its low altitude and the limited resilience of the shoreline, which also results from anthropogenic modifications mainly started from the 1950s. In this study, a refined local geocentric sea-level time series for the period 1993–2020 has been reconstructed by processing data from tide gauges and satellite altimetry. Additionally, to assess the influence of vertical land movements on the relative sea level, InSAR datasets available from 2006 to 2020 have been incorporated into the analysis. After signal processing, time series representing relative sea-level changes across the entire coastal plain were produced on a spatial grid with a resolution of 500x500 meters. A relative sea level rise, ranging from 55% to 640% stronger than the geocentric one, is observed across the entire domain, with critical spots due to localized subsidence related to underground fluid exploitation, leading to severe flooding threats
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
Human-induced landscape modification in the in the last two centuries in the Po delta plain (northern Italy)
Full text linkHistorical maps with high degree of accuracy permit quantitative reconstructions of past land use and land cover (LULC), crucial to assess the impact of human activities on landscape evolution. After georeferencing in a modern reference system, the Carta del Ferrarese commissioned by Napoleon Bonaparte and completed in 1814, has been used to quantify the changes in LULC, occurred in the last two centuries in the Po delta plain. The map depicts a palaeo-landscape dominated by wetlands (49 % of the study area) and agricultural areas (41 %), whereas forests appear already largely depleted (5 %). The Piantata Padana, a traditional agroforestry system with live trees used to support grapevines, is dominant (62 % of the agricultural areas). The comparison with the 2014 LULC map highlights a dramatic reduction (85 %) of wetland areas and the replacement of the Piantata Padana with bare arable lands, with the consequent removal of 4–40 million trees. Soils of areas formerly occupied by wetlands show high organic-carbon content, highlighting the potential of humid areas in carbon sequestration. Land reclaiming, prompted by the introduction of steam pumps, favoured the economic development of the area, but concurred to CO2 emissions through the oxidation of soil organic substances, energy consumption from pumping stations, and the extensive use of hydrocarbon fuels in agriculture. Although urbanisation is limited in the Po delta plain, this area appears nowadays largely shaped by human activities, with the dominance of lands devoted to agriculture, dissected by a dense network of draining channels. The landscape changes recorded in the last two centuries in the Po coastal plain have been uniquely driven by human activities, like in several coastal plains worldwide
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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