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Carbon capture in agroforestry systems in Peru
Get PDFLos sistemas agroforestales han sido reconocidos mundialmente desde hace unas décadas atrás por sus beneficios económicos y de conservación de suelo, agua y biodiversidad. En el Perú esta técnica se está extendiendo principalmente en la Amazonía, con el uso del componente forestal que brinda
sombra a los principales cultivos de exportación como café y cacao, entre otros frutales. Sin embargo, los sistemas agroforestales representan muchos beneficios económicos y ecológicos, como la conservación de las propiedades del suelo, conservación de la biodiversidad, agua y aire. La importancia de los sistemas agroforestales en la captura de carbono se resume en dos conceptos: el primero es que los árboles se convierten en sumideros de carbono a largo plazo al capturar carbono mediante la fotosíntesis y el segundo es que reducen la necesidad de deforestar nuevos bosques para una agricultura migratoria deficiente. El propósito de esta revisión es analizar el potencial de la captura de carbono en los sistemas agroforestales en el Perú para lograr una agricultura sostenible económica y ecológicamente con esta técnica agroforestal. La información obtenida refleja mediciones en centros de experimentación y parcelas de agricultores en regiones de la amazonia peruana como: Huánuco, San Martin, Ucayali, Loreto, Pasco, Amazonas, Madre de Dios y Puno. Estos estudios mayormente presentan resultados de evaluaciones de stock de carbono, mas no de captura de carbono como lo indica el título, la captura de carbono debe ser evaluado durante un periodo de tiempo para obtener la cantidad de carbono capturado de la atmosfera en una unidad de espacio y por una unidad de tiempo (Mg/ha/año). Resaltan los sistemas agroforestales de Huánuco y Loreto, el primero con un stock de carbono de 344,24 Mg/ha en un sistema agroforestal de cacao (Theobroma cacao L.) y otras especies forestales de más de 16 años y el segundo con 288,98 Mg/ha en un sistema agroforestal de castaña (Bertholletia excelsa Bonpl.), umari (Poraqueiba sericea Tul.), tornillo (Cedrelinga cateniformis (Ducke) Ducke) y pashaco (Senna multijuga (Rich.) H.S. Irwin & Barneby) sin edad conocida. Además, existe una falta de estandarización de metodologías en la estimación de carbono sobre y debajo del suelo, para poder realizar comparaciones y estudios a una mayor escala. Concluimos que los sistemas agroforestales representan la mejor opción en el secuestro de carbono después de los bosques naturales y presentan una tecnología económica y ecológicamente sostenible, la cual se busca en la actualidad para evitar los efectos de la deforestación y el calentamiento global. Proponemos a estos sistemas como solución frente al avance de tierras degradadas por la agricultura tradicional de corte y quema, procurando mayor investigación de todos sus aspectos y componentes, para dilucidar los procesos elementales que impulsan o limitan el uso de los sistemas agroforestales
Carbono almacenado en la biomasa aérea y su valoración económica en los sistemas agroforestales de la EEA San Bernardo, Madre de Dios - Perú
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Agroforestry systems are a sustainable management alternative for land degraded by conventional agriculture in the Peruvian Amazon, this could prevent further deforestation of forests and the loss of more ecosystems. The tree component in agroforestry systems makes them more similar to natural forests than many other land use systems such as pastures, monocultures, among others. This characteristic also affects the carbon sequestration potential of agroforestry systems, since they represent a considerable carbon sink both above and below ground. Consequently, it can represent a considerable economic income from carbon credits, which is an international decontamination mechanism to reduce polluting emissions to the environment, with a relatively new market and with great relevance in mitigating climate change. In this sense, the carbon stored in the aerial biomass of seven agroforestry systems established more than 16 years ago at the San Bernardo Agricultural Experimental Station (EEA) was quantified and economically valued. The diameter of fruit and forest species was used as input for the allometric equations that allowed us to estimate biomass and carbon stored in the tree component of agroforestry systems. The seven agroforestry systems of the EEA San Bernardo have a total of 483.81 Mg of carbon stored in their aerial biomass. This amount of carbon represents USD 13,353.16 en bonos de carbono para el precio del 2020. La castaña (Bertholletia excelsa Bonpl.) fue la especie con mayor cantidad de carbono almacenado entre los siete sistemas agroforestales, mientras que el pashaco (Schizolobium amazonicum Huber ex Ducke) mostró una considerable cantidad de carbono almacenado a pesar de tener solo cinco años de haber sido plantado. Nuestros resultados demuestran que algunas combinaciones de especies forestales y frutales generan una competencia interespecífica que favorece al SAF haciéndolo más productivo en términos de crecimiento y de almacenamiento de carbono
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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