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Soil carbon sequestration through crops rotation in a Mediterranean Cambisols: measurement and modelling
Full text linkEGU21-6372
https://doi.org/10.5194/egusphere-egu21-6372
EGU General Assembly 2021
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
Soil carbon sequestration through crops rotation in a
Mediterranean Cambisols: measurement and modelling
Enrico Balugani, Martina Maines, Denis Zannoni, Alessandro Buscaroli, and Diego Marazza
Bologna University, Bologna University, CIRSA, Italy ([email protected])
Soil carbon sequestration (SCS) has been identified by the IPCC as one of the most promising and
cheap methodology to reduce atmospheric CO2. Moreover, an increase in soil organic carbon
(SOC) levels improves soil quality by increasing soil structure (and, hence, resistance to erosion)
and promoting soil ecosystems services like water retention, productivity, and biodiversity. Various
agricultural techniques are available to increase SOC; among them, crop rotation can improve SOC
through soil coverage, changes in water regimes, increase in both carbon inputs, and increase in
soil aggregates formation.
SOC dynamic models, such as RothC, have been suggested by the IPCC as a way to evaluate the
SCS potentials of different soils. Such models could also be used to evaluate the sequestration
potential of different agricultural practices. Moreover RothC allows to estimate the time within
which the SOC variation, due to a certain agronomic management, can be considered significant
as measurable above a threshold value.
In this study, we evaluated the SOC changes for different crop rotations through direct
measurements and RothC modelling, with the objective of: (a) estimating their SCS potential, and
(b) propose a robust monitoring methodology for SCS practices. We performed the study in an
agricultural field close to Ravenna (Italy) characterized by Cambisols and humid subtropical
climate. Soil carbon content was assessed before the setup of the crop rotation, and after 3 years
of rotation. A RothC model was calibrated with field data, and used to estimate SOC dynamics to
50 years, in order to assess long-term SCS. The model results were also used to assess the best
methodology to estimate the SOC variation significance.
The measured SOC was similar to the equilibrium SOC predicted by the RothC model, on average,
for the crop rotations. The measurements showed that the SOC, already low at the beginning of
the experiment, further decreased due to the crop rotation practice. Of those tested, the best for
SCS involves the following crops: corn, soybeans, wheat on tilled soil, and soybeans; while the
worst is with corn, wheat on tilled soil, and wheat on untilled soil. However, the SOC variations
predicted by RothC for the various rotations were too small to be observable in the field during
experimentation. This could be due both to the uncertainty associated with SOC sampling and
analysis, and to the short duration of the experiment. The moving average computations on the
simulation values allowed us to assess the time required to measure the long-term trend of SOC
variation as significant with respect to the environmental background, instrumental error, and SO
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
Lo stoccaggio di carbonio organico nei suoli come indicatore addizionale negli studi di Product Environmental Footprint: il modello RothC applicato a un uliveto biologico in Italia
No full textQuesto articolo presenta l’applicazione del modello RothC, suggerito dalle Product Environmental Footprint Category Rules (PEFCR) dell’olio di oliva, attualmente in fase di bozza, per il calcolo dello stoccaggio del carbonio organico nel suolo in un’area coltivata ad ulivi della regione Lazio. Il quadro di riferimento è il metodo Product Environmental Footprint (PEF) sviluppato dalla Commissione Europea, che è in fase di sperimentazione all’interno del progetto LIFE EFFIGE. I risultati mostrano che la scelta delle pratiche colturali, ed in particolare delle colture di copertura, può agire come fattore di mitigazione su un orizzonte temporale di un centinaio di anni. Si osserva inoltre che il modello RothC, nonostante permetta di evidenziare informazioni addizionali importanti relative allo stoccaggio di carbonio organico negli studi PEF, richiede un utilizzo di dati e conoscenze tali da metterne in dubbio l’applicabilità in autonomia da parte delle imprese
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
SOIL SURVEY AND CLASSIFICATION IN A COMPLEX TERRITORIAL SYSTEM: RAVENNA (ITALY)
Full text linkIn the context of the PRIN 2007-2009 project, “Geochemical evaluation of agro-environmental quality in a complex territorial system: the case of Ravenna”, thirteen pedological profiles (nine in a coastal pinewood, two in farmland and two in urban park) were established. The profiles were described, sampled and analyzed so as to obtain an overview of the pedological complexity of the studied areas.Inside the pinewood, the soils were greatly influenced by their topographic location and the vicinity of the superficial aquifer. The deeper layers were Typic Ustipsamments, the more superficial ones Typic Psammaquents and the intermediate ones Aquic Ustipsamments. The two farmland soils were Udifluventic Haplustepts, with slight differences due to the origin of the soil and its use. In the park, both soils were also Udifluventic Haplustepts with a human interfecence evidenced by the abundance of brick fragments in the profiles
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