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Valutazione di efficacia di gestione delle aree protette attraverso l’uso di indicatori oggettivi: una applicazione ad un sistema di aree umide del litorale tirrenico.
No full textQuesta tesi di dottorato illustra i risultati di processi di valutazione basati sul "Project Cycle": quadro concettuale sviluppato dall'Unione Internazionale per la Conservazione della Natura (IUCN) finalizzato a misurare l'efficacia della gestione nelle aree protette.
Per la prima volta in Italia, due metodologie sono state applicate sistematicamente per: a) valutare le minacce e misurare l'efficacia delle azioni di conservazione attraverso l’analisi delle stesse minacce (Threat Analysis - TAN) con l'identificazione, la classificazione e la loro gerarchizzazione agli obiettivi di biodiversità; b) valutare la conseguente riduzione delle minacce (Threat Reduction Assessment - TRA) a seguito di interventi di conservazione.
La ricerca include casi di studio all'interno di un sistema di zone umide poste lungo le aree costiere tirreniche di Lazio e Toscana, aree protette classificate anche come siti Natura 2000:
• “Palude di Torre Flavia”, designata anche come Zona di Protezione Speciale (ZPS) IT6030020 "Torre Flavia" (Roma, Lazio, Italia);
• “Palude Diaccia Botrona”, designata sia come Zona Speciale di Conservazione (ZSC) che come ZPS IT51A0011 "Palude Diaccia Botrona" (Grosseto, Toscana, Italia).
Per quanto, tuttavia, la ricerca si estenda a casi posti anche in aree geografiche diverse, i target di conservazione selezionati sono gli uccelli Sternula albifrons, Sterna hirundo, Charadrius alexandrinus e Charadrius dubius e i rettili Rafetus swinhoei, Cyclanorbis elegans e Caretta caretta. In particolare, per quest’ultima specie, la metodologia TAN non risulta essere stata mai applicata prima in tutto il mondo. In questi contesti, il quadro di valutazione delle minacce è stato declinato agli obiettivi di biodiversità attraverso un approccio basato su esperti.
Questo progetto di dottorato ha dimostrato l’importanza di un criterio strutturato che vada oltre il paradigma per tentativi ed errori che ha caratterizzato gran parte della gestione dei siti naturali negli ultimi decenni. La ricerca evidenzia come i disturbi antropici siano parte di una catena causale che collega le principali forze motrici, attraverso minacce indirette, a quelle che esercitano impatti diretti sugli obiettivi di conservazione. Questo approccio aiuta ad andare oltre la complessità e l'interdipendenza delle relazioni, utilizzando quadri concettuali.
In tutti i casi affrontati che coinvolgono uccelli e rettili marini nel Mediterraneo, i rifiuti e il degrado degli habitat riproduttivi sono emersi come minacce significative per la conservazione delle specie. L'approccio collaborativo, che ha interessato esperti locali e la comunità scientifica, si è rivelato nella maggior parte dei casi essenziale anche per evidenziare l'eventuale esposizione a bias cognitivi. Pur promuovendo in tale contesto ogni tipo di relazione tra il mondo naturale e la sfera umana, attraverso anche il ricorso ad un auspicabile approccio analitico (DPSIR), si ritiene di aver fornito una visione trasversale, assolutamente necessaria nella valutazione delle minacce perché in grado di interpretare rapidamente le possibili soluzioni da attuare.
In definitiva, i casi esaminati hanno sottolineato l'importanza di massimizzare la coerenza procedurale con le azioni di conservazione. In questo quadro, i decisori sono stati incoraggiati a operare in modo proattivo, aspetto che ha indotto ad avanzare nella tesi anche alcune proposte riconducibili a misure o azioni volte a rafforzare il processo di valutazione
Mercurio e selenio nelle uova di Larus cachinnans e Larus audouinii (Laridae) dell'Arcipekago Toscano e della Sardegna
No full textEvaluating the Effectiveness of a Conservation Project on Two Threatened Birds: Applying Expert-Based Threat Analysis and Threat Reduction Assessment in a Mediterranean Wetland
Full text linkWe applied two recent approaches largely used in biological conservation: Threat Analysis (TAN) and Threat Reduction Assessments (TRAs), assessing the effectiveness of a project focused on two water-related bird species (common tern, Sterna hirundo and little tern, Sternula albifrons), commonly breeding in some wetlands of Italy. We used the IUCN standardized lexicon for the classification of threats, utilizing a panel of experts to assess a set of regime attributes (extent, severity and magnitude) of each human-induced disturbance. Our aims were: (i) through the TAN approach, to carry out an arrangement and quantification of the main threats acting on our focal species and select the priority ones; (ii) through the TRA approach, to test the effectiveness of an operational project focused on mitigating the threats and improving the breeding success of species (i.e., building rafts and floating islands to encourage their nesting). Using the TAN approach, experts identified the following human-induced threats (IUCN code): 6.1—Generic disturbance; 7.2—Water stress; 7.3—Salinization; 8.8—Vagrant dogs; 8.8—Mediterranean gulls; 8.8—Wild boars, all significantly different in their magnitude. Among them, wild boars and Mediterranean gulls appeared the priority threats with the greatest extent, intensity and magnitude. Using the TRA approach, after the project, we assessed an overall decrease in the threat magnitude of 23.08% (21.42% when considering only the threats directly affected by our project). These data suggest that further efforts should be devoted to achieving greater effectiveness of conservation actions focused on our target species. With limited time and resources to quantify threats, expert-based approaches could be useful for rapidly assessing the effectiveness of small conservation projects by providing a range of scores obtained following an analytical procedure. In this regard, Threat Analysis and Threat Reduction Assessment could be considered useful tools to support adaptive management in project management cycles
Temporal and geographical variations of mercury and selenium in eggs of Larus michahellis and Larus audouinii from central Mediterranean islands
No full textIn this study, we determined mercury and selenium levels in abandoned unhatched eggs of the yellow-legged gull (Larus michahellis) and Audouin’s gull (Larus audouinii) collected during 2004–2005 from the Tuscan archipelago and Sardinia (Italy). The different feeding habits of the two species probably determine the different uptakes of trace elements, as the study shows highly significant differences for selenium and mercury levels as well as shell thickness and Hg:Se molar ratio values. Audouin’s gulls nesting on the coasts of the Tuscan archipelago showed significantly higher selenium levels than did gulls from colonies from the islands around Sardinia. Comparisons with a similar investigation previously conducted in the same area suggested that mercury and selenium concentrations, although in line with reports in the literature, were significantly lower than levels encountered in gulls in the early 1980s. Mercury (mg/kg d.w.) dropped from 8.631 to 5.030 in Audouin’s gulls and from 2.509 to 0.828 in yellow-legged gulls. The regional decline in mercury levels following reduced use of the metal in industry and the probable food depletion effects linked to the overfishing of fish prey of these two gull species are discussed as hypotheses that could explain the decrease in mercury levels found in eggs
Monitoring Effectiveness of an Operational Project on Two Threatened Landbirds: Applying a Before–After Threat Analysis and Threat Reduction Assessment
Full text linkHuman activities are at the origin of anthropogenic threats altering ecosystems at any hierarchical level. To mitigate them, environmental managers develop projects to obtain effective outcomes on biological targets of conservation concern. Here, we carried out two new approaches (TAN = Threat Analysis and TRA = Threat Reduction Assessment) aimed at assessing the effectiveness of conservation actions on two threatened beach-nesting landbird species, the Kentish Plover (Charadrius alexandrinus) and the Little Ringed Plover (C. dubius), breeding along a coastal beach of central Italy. Using a score-based evaluation (TAN approach), a panel of experts assessed the extent, intensity, and magnitude of a set of species-specific threats, ranking them from more to less impacting. Domestic dogs, dune trampling, and synanthropic predators appeared as the threats with the most significant magnitudes. Using the TRA approach, experts obtained a rank of threats that were more urgent to solve: i.e., domestic dogs and dune trampling. To contrast with these threats, in 2021, we carried out a conservation project with specific measures that were aimed at reducing the threat magnitude on birds. They included: dune borders demarcation, anti-predatory cages on plover nests, the removal of beach-stranded fishing lines and hooks, field surveillance by volunteers, dog control, social- and mass-media communication, and alliances with stakeholders and institutions. After the project, mechanical beach grooming (>80%), dune trampling, and synanthropic predators (both >60%) showed the highest percentage of impact reduction. The project showed a medium–high level of effectiveness in reducing the total threat magnitude (TRA-I index = 63.08%). The Threat Analysis should be routinely used to arrange a causal chain that is useful for defining the relationships among human-induced threats and ecological targets, selecting the threats with the highest magnitudes. After the projects, the Threat Reduction Assessment may assess the level of threat reduction, suggesting measures for adaptive management
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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