1,720,962 research outputs found
Il biochar e il suo potere fertilizzante: una opportunità per l'uso ecosostenibile del suolo agrario.
No full textCo-application of wood distillate and biochar improves soil quality and plant growth in basil (Ocimum basilicum)
No full textBackground: Nowadays, an ever-increasing attention toward eco-friendly and sustainable agricultural practices, such as the use of biological fertilizers that do not alter the ecological balance of soil, has been grown worldwide. Aim: To evaluate the effect of wood distillate (WD), biochar (B), and their combination (BWD) in increasing soil biomass, soil biological activities, and plant growth in basil (Ocimum basilicum L.) by determination of plant biomass. Methods: Plants of basil were cultivated in greenhouse with three different amendments. WD was applied at a 1% dilution through fertigation. B was applied at a rate of 2% (w/w) corresponding to 34 t ha–1. Organic carbon (OC), dissolved organic carbon (DOC), soil microbial biomass carbon (MB-C), and enzymatic activities (dehydrogenase, phosphatase, arylsulfatase, β-glucosidase, and urease) were determined at the end of the cultivation period (4 weeks) in bulk soil and in the rhizospheric soil. The alteration index three (AI3), which calculates the balances between three enzymes and potentially allows to quantify in relative terms the differences between soils due to different management practices, was also determined. Results: WD and B significantly increased OC and MB-C content, whereas B preferentially retains soil DOC species and the organic substance of the WD in the BWD treatment. Phosphatase and urease activities were the most increased with the combination of the two amendments. AI3 in controls suggests that the application of WD and B at the right doses promotes the activity of soil microorganisms, enhancing the soil biological quality. Conclusion: The presence of the two organic sources increased the availability of nitrogen and phosphorus, with a positive response in terms of basil dry biomass. WD and B have been confirmed as suitable and sustainable amendments for potential application in crops cultivation
Effects of combined biochar and vermicompost solution on leachate characterization and nitrogen balance from a greenhouse tomato (Solanum lycopersicum) cultivation soil
No full textBoth biochar (B) and vermicompost (V) can provide the soil with soluble organic matter. We evaluated the effect of B in reducing nitrate and dissolved organic carbon (DOC) losses from soil via leaching together with the effect of B combined with V solution (vermiwash) in increasing the efficiency of plant nitrogen. Tomato plants (Solanum lycopersicum L.) were cultivated in a greenhouse with soil under three different amendments (B, V and a mix BV). B was applied at a rate of 2% w/w corresponding to 34 t ha−1. V was applied at 25 mg per plant through fertigation. Leachate and soil were monitored in terms of nitrates and DOC throughout the trial (120 days), and plants and fruits were monitored in terms of nitrogen balance index (NBI) and dry matter biomass. B and BV significantly decreased NO3–_N content in the leachate in all recovered times by 66.8% and 71.3%, respectively. In contrast, the absence of biochar in the V treatment led to a 38.1% increase in NO3–_N concentration. Similar results were found for DOC content. The dry biomass of plants increased in B and BV treatments by 19.5 and 28.7%, respectively. The dry biomass of tomato fruits was enhanced by 18.5, 12.1, and 37% in V, B and BV treatments, respectively. Synergisms were found between the char material and complex organic compounds derived from the vermicompost process in terms of safeguarding the quality of the soil, the underground water, and the sustainability of crops. © 2021 Taylor & Francis Group, LLC
Effetti del biochar sulla mineralizzazione della sostanza organica del suolo: prove di laboratorio.
No full textUna potenziale via di abbattimento dei livelli crescenti di CO2 nell'atmosfera è l'uso della pirolisi per convertire la biomassa vegetale in una forma più stabile di carbonio (biochar), che può poi essere applicato al suolo.
Allo scopo di valutare l'interazione tra biochar e sostanza organica del suolo e di mettere in evidenza eventuali priming effects indotti dal materiale, è stata effettuata un’incubazione di breve periodo, in laboratorio, trattando un suolo con dosi di applicazione di 0, 2, 4, 6, 8 e 10% in peso, misurando per 21 giorni la respirazione microbica mediante lo sviluppo di CO2.
Gli effetti del biochar sulla mineralizzazione della sostanza organica nativa (priming effect) sono stati valutati attraverso la comparazione tra il rilascio di CO2 dal suolo (controllo) e quello misurato nelle miscele di biochar e suolo. A tal fine è stata calcolata una retta di regressione con i dati cumulativi di C-CO2 emesso dalle miscele biochar–suolo rispetto al C fornito con il materiale, che ha permesso di stimare il C-CO2 emesso ad una dose di applicazione pari a zero. Il valore ottenuto è stato infine confrontato con il corrispondente dato misurato nel controllo, ottenendo così il priming ratio.
I risultati mostrano che dal suolo ammendato con biochar è stata rilasciata una maggior quantità di carbonio sottoforma di CO2 rispetto al controllo, con aumenti lineari rispetto alla quantità di C aggiunto.
L’assenza di priming effect, confermato dal valore prossimo a 1 del priming ratio, indica che l’incremento di CO2 non proviene da un maggior rilascio di carbonio della sostanza organica nativa e quindi che una frazione del carbonio del biochar viene perduta per respirazione microbica. La perdita di C da parte del biochar, pari a circa 0.006%, è tuttavia molto modesta e, vista la netta tendenza alla diminuzione nell’entità della mineralizzazione già durante la breve durata dell’incubazione, è presumibile che le perdite di C del materiale nel lungo periodo siano nettamente inferiori alla quantità dell’elemento aggiunto al suolo con l’ammendamento. Considerato il lunghissimo tempo medio di residenza nel suolo del carbonio del biochar, il modesto rilascio di carbonio per respirazione microbica non pare quindi compromettere la capacità del materiale di contribuire al sequestro di C nell’ecosistema suolo
I gesuiti e il principe. Il modello francese nella politica dell'assistenza di fine Seicento
No full textGrazie a ricerche effettuate negli archivi francesi, si attribuisce la paternità delle iniziative assistenziali in Francia e in alcuni Stati italiani alla fine del XVII secolo al gesuita Chaurand, anziché al suo allievo Guevarre
Using Biochar and Vermiwash to Improve Biological Activities of Soil
No full textThe recycling of key nutrients and bioenergy from waste materials is a goal of sustainable agriculture. The co-application of biochar and a vermicompost solution (vermiwash) could enhance the positive effects of both materials on soil biomass and biological activities. Tomato plants were grown in soil amended with biochar, mixed at a rate of 2% w/w, and vermiwash, applied through fertigation at a rate of 25 mg per plant, alone (B and V) and in combination (BV). Organic C, dissolved organic C (DOC), soil biomass C, and some enzymatic activities were determined at the start (T0) and the end (T100) of the cultivation period in bulk soil and rhizosphere soil. B and V significantly increased the organic C and soil biomass contents. In addition, B retained the DOC species derived from the soil and, in the BV treatment, also the humic substance of the vermiwash. Generally, all the parameters achieved higher values in the rhizosphere than in the bulk soil. The altered soil index three (AI3) of enzyme activities suggests that applying V and B is helpful for the soil microorganisms. Synergisms between B and V were low in the bulk soil and clearly evident in the rhizosphere
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
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