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Sustainable management of water resources in large river basins in a climate change scenario – A case study of Po River Basin
No full textLe risorse di acqua dolce a livello globale sono sotto pressione a causa dell'aumento delle emissioni di gas serra, dell'aumento delle temperature e del forzamento antropogenico. Il settore agricolo, in quanto principale consumatore di acqua dolce, è particolarmente vulnerabile a questi cambiamenti. Il bacino del fiume Po, il più grande bacino fluviale e centro agricolo d'Italia, negli ultimi anni ha subito frequenti siccità. Questo studio intende fornire alcune informazioni sulla gestione sostenibile delle risorse idriche nei grandi bacini fluviali colpiti dal cambiamento climatico. Gli obiettivi specifici comprendevano l'analisi delle tendenze climatiche storiche, la valutazione dei modelli di evapotraspirazione e la valutazione delle minacce di aridità nel bacino del Po su scala stagionale e spaziale. I test di Mann-Kendall e stagionali di Mann-Kendall, combinati con la pendenza di Theil-Sen, sono stati applicati per rilevare le tendenze passate e i tassi di cambiamento dal 1960 al 2020. La classificazione pluviometrica di Bandini per l'Italia è stata aggiornata utilizzando i dati attuali per meglio caratterizzare i regimi di precipitazione. I dati relativi alla temperatura e alle precipitazioni sono stati estrapolati altitudinalmente per eliminare gli effetti della quota, e sono state elaborate mappe climatologiche mensili aggiornate per il bacino. Il fabbisogno idrico del bacino è stato valutato utilizzando l'evapotraspirazione potenziale di Thornthwaite (indicativa della domanda d'acqua dell'ecosistema come caratteristica climatica) e l'evapotraspirazione delle colture ottenuta dall'evapotraspirazione di riferimento di Hargreaves e Samani corretta con i coefficienti di coltura (secondo le classi di copertura del suolo accoppiate con il metodo FAO). Inoltre, la domanda di evapotraspirazione delle colture è stata determinata per quattro scenari colturali: miglio e lenticchie, orzo e lenticchie, frumento invernale e fagiolo verde, riso e lenticchie. Le tendenze spaziali e temporali dell'aridità sono state valutate utilizzando quattro indici di aridità basati su due diversi aspetti. Essi son oindici basati su temperatura e precipitazioni, cio gli indici di aridit' di e indici di De Martonne e De Martonne Pinna sul l'evapotraspirazione, cioè indici di aridità di Melisenda e Budyko. I risultati hanno mostrato tendenze significative verso l'alto in tutte le metriche di temperatura, soprattutto durante le stagioni estive con tassi da 0,5 \degree C a 0,7 \degree C per decennio. Oltre l'80\% del bacino presentava una domanda evapotraspirativa delle colture superiore a quella potenziale, indicando esigenze di irrigazione. Mentre il bacino è classificato come umido su base annua, circa il 40\% sperimenta condizioni mediterranee o semi-aride durante l'estate, che coincide con la stagione di crescita massima. Tra quelli considerati, lo scenario di coltivazione del riso e delle lenticchie ha mostrato il deficit idrico più elevato, raggiungendo i 500 mm annui. Questi risultati evidenziano la necessità di un'azione immediata attraverso strategie sostenibili che includano selezione delle colture, efficienza dell'irrigazione e gestione integrata delle risorse idriche per garantire la sostenibilità idrologica e agricola del bacino.Freshwater resources globally are under stress due to increasing greenhouse gas emissions, rising temperatures, and anthropogenic forcing. The agricultural sector, as the largest consumer of freshwater, is particularly vulnerable to these changes. The Po river basin, Italy's largest river basin and agrarian hub, has been experiencing frequent droughts in recent years. This study set out to provide some insights regarding the sustainable management of water resources in large river basins suffering from climate change.
The specific objectives included the analysis of historical climatic trends, assessment of evapotranspiration patterns and, evaluation of aridity threats across the Po river basin on seasonal and spatial scales. Mann-Kendall and seasonal Mann-Kendall tests, combined with Theil-Sen's slope, were applied to detect past trends and rates of change from 1960 to 2020. The classical Bandini Pluviometric classification for Italy was updated using current data to better characterize precipitation regimes. Temperature and precipitation data were altitudinally detrended to eliminate elevation influences, and updated monthly climatological maps were developed for the basin. The basin’s water demand was assessed using Thornthwaite potential evapotranspiration (indicative of ecosystem water demand as a climatic characteristic) and crop evapotranspiration obtained from the Hargreaves and Samani's reference evapotranspiration adjusted with crop coefficients (as per Corine land cover classes). Additionally, crop evapotranspiration demand was determined for four cropping scenarios which were millet and lentils, barley and lentils, winter wheat and green beans, and rice and lentils. The spatial and temporal trends in aridity were assessed using four aridity indices based on two different aspects. Temperature and precipitation-based i.e., De Martonne and De Martonne Pinna combinative indices, and evapotranspiration-based i.e., Melisenda and Budyko aridity indices.
Results showed significant increasing trends in all temperature metrics, most prominently during summer seasons with rates of 0.5 degree C to 0.7 degree C per decade. Over 80% of the basin showed higher crop evapotranspiration than potential evapotranspiration, indicating irrigation needs. While the basin is classified as humid on an annual basis, about 40% experiences Mediterranean to semi-arid conditions during summer, coinciding with peak growing season. The rice-lentils cropping system showed the highest water deficit, reaching 500 mm annually. These findings highlight the need for immediate action through sustainable strategies including crop selection, irrigation efficiency, and integrated water resources management to ensure the basin's hydrological and agricultural sustainability
GIS--based application of Benfratello's method to estimate the irrigation deficit and its variability in the Capitanata plain under climate change
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
Modelling the impact of land use changes on the hydrological regimes of Perak River Basin
No full textRainfall and land use (LU) changes play a key role in the hydrologic behaviour of a
watershed such as runoff generation and its regulation. Recent increasing trends of
flooding in Perak have made it ambiguous that how much changes in thesefactots oh
the spatio-temporal scale can affect the hydrology of Perak River Basin and its
tributaries
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
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