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Valutazione dello stato morfologico ed ecologico di corsi d'acqua alpini: utilizzo e confronto dell'indice di qualità morfologica (IQM) e di un indice basato sugli odonati
Full text linkThis thesis deals with the assesment of morphological and ecological conditions of six Italian alpine rivers. Odonata (dragonflies) were chosen as bioindicators to assess the ecological status of river corridors while the assessment of th morphological status of the study cases was performed by using the Morphological Quality Index (MQI) Dragonflies demonstrated to be an effective bioindicator. The results also indicated a significant correlation between MQI and OQI and demonstrated the importance of river processes as drivers for the maintenance of a high diversity of habitats and species within the river corridor
Utilizzo degli Odonati come indicatori dello stato ecologico dei corsi d’acqua e strumento di monitoraggio di interventi di riqualificazione fluviale
No full textAssessment of morphological and ecological conditions of Italian alpine rivers using the Morphological Quality Index (IQM) and Odonata
No full textOdonates as indicators of the ecological integrity of the river corridor: Development and application of the Odonate River Index (ORI) in northern Italy
No full textThe assessment of the ecological conditions of rivers is crucial for their appropriate management andrestoration. Bioindicators commonly used to evaluate the river status (i.e. diatoms, aquatic macrophytes,benthic macroinvertebrates and fish) detect alterations of water quality, but are not particularly sensitiveto hydromorphological degradation, which is another relevant pressure in river systems. Furthermore,those bioindicators are usually applied only to flowing channels. We developed a new multimetric index,the Odonate River Index (ORI), to assess the conditions of the whole corridor in alluvial rivers. The ORIis a development of an evaluation system proposed in Austria, and based on the Odonate Habitat Index(OHI). Odonates were chosen as bioindicators for the ecological integrity of the river corridor, since thistaxon provides information on the conditions of their aquatic breeding sites, as well as on the surroundingterrestrial areas, due to its amphibiotic life cycle. We used a case study of 18 reaches from six Italian Alpinerivers, characterized by different morphological conditions and level of human impact. Within each studyreach, we selected four sites, both lotic and lentic sites. Dragonfly surveys consisted in field observationof adults, and collection of larvae and exuviae. To define the best sampling strategy, we compared theresults of the ORI metrics obtained varying the input data by combining different sampling methods: thebest compromise between effort and exhaustiveness was obtained coupling the observation of adultswith the collection of exuviae. We found the ORI to be a robust and reliable tool to assess the status ofthe river corridor in a wide range of environmental conditions and river morphology, being particularlysuitable to detect hydromorphological degradation and alterations of the structure of aquatic and riparianvegetation. We identified two limiting factors for the applicability of this index: low water temperaturesof the main channel (i.e. mean annual value below 10◦C) and river reaches with no or scarce aquatic andriparian vegetation. In addition to the assessment of river conditions, the ORI could also be applied formonitoring the effects of river restoration actions
Assessment of morphological and ecological conditions of Italian alpine rivers using IQM and Odonata
No full textThe Odonate Habitat Index (OHI) revisited: an improved methodology tested in six Alpine Italian rivers
No full textTowards a more comprehensive assessment of river corridor conditions: A comparison between the Morphological Quality Index and three biotic indices
No full textRiver management and planning of restoration actions require a detailed analysis of stream conditions. However,
most biotic and hydromorphological indices that have been developed for implementing the European Water
Framework Directive (WFD) are characterized by limited spatial and temporal scales of application. In addition,
the indices based on the biological quality elements defined by the WFD are sensitive to water quality but not to
hydromorphological alterations. To overcome these limitations, alternative hydromorphological and biotic indices
have recently been developed.
In this study we compared the results obtained with the Morphological Quality Index (MQI) to those of three
biotic indices, the Odonate River Index (ORI) and two BQE-based indices, in seven rivers of northern Italy. MQI
and ORI resulted highly and significantly correlated, and alterations of river functionality and continuity were
the most relevant impacts affecting dragonfly assemblages. Conversely, no significant relationships were found
between the MQI and both BQE-based indices and assemblages. The significant correlation between MQI and
ORI can be explained by the correspondence of the spatial scale of application (i.e. the whole river corridor). In
contrast, the lack of correlation between the BQE-based indices and MQI can probably be attributed to the
different spatial scales at which the indices work.
The results of this study underline the importance of evaluating the lateral dimension of the river corridor and
the need to apply reach-scale indices to achieve a comprehensive evaluation of river corridor conditions and to
define appropriate management actions
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
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