Soil carbon sequestration rates under Mediterranean woody crops using recommended management practices : A meta-analysis

This work was supported by the projects: CARBOLIVAR (P11-RNM-7186) funded by Consejería de Innovación, Ciencia y Empresa of Junta de Andalucía and GEISpain project (CGL2014‐52838‐C2‐1‐R) funded by Ministerio de Economía y Competitividad, both including European Union ERDF funds. This work was also supported by the FPU 2012 grant program of the Ministerio de Educación, Cultura y Deporte of Spain. Dr. Roberto Garcia-Ruiz and Eduardo Aguilera gratefully acknowledge support by the Sustainable Farm Systems project (SSHRC 895-2011-1020) funded by the Canadian Social Sciences and Humanities Research Council.Peer reviewedPostprin

Soil organic carbon sequestration in olive groves of Andalusia: effect of the managements on soil organic carbon dynamics

[ES]Esta tesis evalúa el efecto de distintos manejos agrícolas sostenibles en el olivar andaluz en la acumulación del carbono orgánico y sus distintas fracciones en el suelo. Particularmente, se ha centrado en el mantenimiento de la cubierta vegetal en la entrecalle del olivar. Además, se han evaluado también los efectos positivos del mantenimiento de la cubierta vegetal en olivares en pendiente en lo referido a la reducción de las pérdidas de carbono orgánico en el suelo por erosión hídrica. Los estudios en campo y en el laboratorio se han complementado con la aplicación de un modelo (RothC) que permitió evaluar el contenido de carbono orgánico en el suelo tras 100 años tras el cambio de un manejo convencional a otros sostenibles. Por otra parte, se realizó un meta-análisis que evaluó la capacidad de secuestro de carbono de los suelos de cultivos leñosos mediterráneos.[EN] This thesis assesses the effect of the different management practices in Andalusian olive groves on the soil organic carbon accumulation, and also on its different fractions. Particularly, it has been focused on allowing the growth of a spontaneous vegetation cover in the inter-row area. Moreover, it has been also evaluated the positive effects of this practice on decreasing soil losses caused by water erosion in high-slope olive groves. Field and laboratory studies have been combined with the running of a model (RothC), which allowed to assess the soil organic carbon content after 100 years after changing the management from conventional to some sustainable managements. Otherwise, a meta-analysis has been also carried out in order to find out the carbon sequestration ability of Mediterranean woody crop soils.Tesis Univ. Jaén. Departamento de Biología Animal, Biología Vegetal y Ecología. Leída el 13 de enero de 201

Scientists in the principal investigator role

The social and economic contributions of R&D are essential in the development of countries, since they are the motor for their progress. Research can be implemented by companies, but it can also be implemented in universities and research centres. The research process is more and more often conducted in teams and these are increasingly multidisciplinary. This is a double-edge sword because, even though diversity among research team members could increase the generation of innovative and creative ideas, this heterogeneity can also have a dark side for the welfare of the research team. Therefore, when both advantages and disadvantages can emerge in a diverse research team, what can diminish the weaknesses and enhance the strengths is the crucial role of an efficient principal investigator managing and leading the research team. Notwithstanding that there are some studies that have focused on the principal investigator role in the literature, the knowledge about them is somewhat scant, because there is still a need for a deeper understanding of this crucial actor in R&D environments. The research work carried out in this Doctoral Thesis aims to address both principal investigators and their environments. With this research, we will deepen the understanding of what influences principal investigators and what they have an influence on, since principal investigators are a key asset in R&D environments. Therefore, the focus of this Doctoral Thesis is on some of the issues that are in the core of the influence of principal investigators on the activities of R&D teams. Particularly, we focus our research efforts on developing a measurement scale of the principal investigator's human capital whose results could allow us to determine whether different principal investigator profiles exist. We also focus on studying whether obtaining public competitive funding could be influenced by the principal investigator's priorities or their gender. Moreover, we focus on the relationship between the level of conflict within a research team and its performance, as well as on the influence that the principal investigator's transformational leadership has on this relationship

Learning definite Horn formulas from closure queries

A definite Horn theory is a set of n-dimensional Boolean vectors whose characteristic function is expressible as a definite Horn formula, that is, as conjunction of definite Horn clauses. The class of definite Horn theories is known to be learnable under different query learning settings, such as learning from membership and equivalence queries or learning from entailment. We propose yet a different type of query: the closure query. Closure queries are a natural extension of membership queries and also a variant, appropriate in the context of definite Horn formulas, of the so-called correction queries. We present an algorithm that learns conjunctions of definite Horn clauses in polynomial time, using closure and equivalence queries, and show how it relates to the canonical Guigues–Duquenne basis for implicational systems. We also show how the different query models mentioned relate to each other by either showing full-fledged reductions by means of query simulation (where possible), or by showing their connections in the context of particular algorithms that use them for learning definite Horn formulas.Peer ReviewedPostprint (author's final draft

Potential Bioenergy Production from Miscanthus × giganteus in Brandenburg: Producing Bioenergy and Fostering Other Ecosystem Services while Ensuring Food Self-Sufficiency in the Berlin-Brandenburg Region

Miscanthus × giganteus (hereafter Miscanthus) is a perennial crop characterized by its high biomass production, low nutrient requirements, its ability for soil restoration, and its cultivation potential on marginal land. The development of the bioenergy sector in the state of Brandenburg (Germany), with maize as the dominant crop, has recently drawn attention to its negative environmental impacts, competition with food production, and uncertainties regarding its further development toward the state’s bioenergy targets. This study aimed to estimate the potential bioenergy production in Brandenburg by cultivating Miscanthus only on marginal land, thereby avoiding competition with food production in the Berlin-Brandenburg city-region (i.e., foodshed), after using the Metropolitan Foodshed and Self-sufficiency Scenario (MFSS) model. We estimated that by 2030, the Berlin-Brandenburg foodshed would require around 1.13 million hectares to achieve 100% food self-sufficiency under the business as usual (BAU) scenario, and hence there would be around 390,000 ha land left for bioenergy production. Our results suggest that the region would require about 569,000 ha of land of maize to generate 58 PJ—the bioenergy target of the state of Brandenburg for 2030—which is almost 179,000 ha more than the available area for bioenergy production. However, under Miscanthus plantation, the required area would be reduced by 2.5 times to 232,000 ha. Therefore, Miscanthus could enable Brandenburg to meet its bioenergy target by 2030, while at the same time avoiding the trade-offs with food production, and also providing a potential for soil organic carbon (SOC) sequestration of around 255,200 t C yr-1, leading to an improvement in the soil fertility and other ecosystem services (e.g., biodiversity), compared with bioenergy generated from maize.Peer Reviewe

La seguridad de las instalaciones deportivas públicas en Extremadura: estudio exploratorio

El objetivo del presente estudio es explorar la seguridad de los espacios y equipamientos deportivos públicos de tipo convencional en Extremadura. Para ello, se analizaron un total de 144 espacios deportivos (terrestres y acuáticos) y se cumplimentaron 3.357 ítems, de acuerdo con los check list elaborados por el Consejo Superior de Deportes (CSD) e Instituto Biomecánico de Valencia (IBV) en 2008. Los resultados muestran que el porcentaje medio total de seguridad en los espacios analizados es de un 67 %. Por instalaciones deportivas, los campos de fútbol son los que presentan menos seguridad (63 %) y las pistas de baloncesto las que más (79 %). Los aspectos generales y de estructura son los que menor porcentaje de seguridad obtienen. En cambio, los aspectos de red en espacios deportivos terrestres son los que mayor seguridad consiguen. Se concluye que los espacios deportivos no cumplen con toda la normativa de seguridad. Se recomienda incluir diferentes medidas en la gestión de las instalaciones deportivas que aumenten la seguridad de la práctica deportiva durante el uso del equipamiento deportivo

You learn when it hurts: evidence in the mutual fund industry

This paper aims to contribute to the lack of research on the learning process of mutual fund markets. The empirical design is focused on the ability of the Spanish equity mutual fund industry to learn from its important errors. The choice of this industry is justified by both its relevance in the European mutual fund markets and some specific characteristics, such as the concentration and the banking control of the industry, which may affect the learning process. Our main objectives are to identify important trading errors in mutual fund management by applying three independent filters based on the relative importance of each decision, and then testing the evolution of these errors both at the industry level and at the fund family level. We apply the dynamic model of generalized method of moments (GMM), and we find an overall significant decrease in the percentage of important trading errors over time, thereby providing evidence of the global learning process of the industry. In addition, we find that a large number of fund families drive this evidence. Finally, we obtain that the family size and its dependence on financial groups do not seem to play significant roles in explaining the learning process. Therefore, we conclude that fund managers have incentives to learn from their important trading errors, in order to avoid them in future decisions, due to their serious negative consequences on fund performance, regardless of the characteristics of the families to which they belong

Is the Spanish market breaking down?: The Feldstein-Horioka approach

Desde el retorno a la Democracia con la Constitución de 1978, España ha experimentado un proceso de descentralización administrativa y política, que ha dotado al estado de una estructura cuasi-federal. Este es un proceso aún inacabado y ha hecho surgir tensiones de signos opuestos. Por un lado, algunos grupos políticos de carácter nacionalista reclaman llevar este proceso hasta su extremo, ejerciendo la autodeterminación. Por otro, se han alzado algunas voces indicando que la descentralización ha ido demasiado lejos y está originando la fragmentación del mercado español, poniendo en peligro la asignación eficiente de los recursos. Este trabajo trata de comprobar si existen indicios empíricos sobre la posible fragmentación del mercado interior utilizando, para ello, el enfoque de Feldstein y Horioka, según el cual la movilidad perfecta del capital, es decir, la plena integración financiera, implicaría que no existe relación entre las tasas de ahorro e inversión de las diferentes comunidades autónomasSince the return to democracy with the 1978 Constitution, Spain has experienced a process of political and administrative decentralization, which has acquired the status of a quasi-federal structure. This, process, still incomplete, has lead to opposite signs tensions. On the one hand, some nationalist political groups claim to bring this process to its extreme, exercising self-determination. On the other hand, some voices have arisen suggesting that decentralization has gone too far and is causing fragmentation of the Spanish market, jeopardizing the efficient allocation of resources. This paper tries to check on the existence of empirical evidence about the possible fragmentation of the internal market, using for this purpose the approach of Feldstein and Horioka, which provides that perfect capital mobility (financial integration), imply that there is no correlation between saving and investment rates of different region

Proposing a Quantum simulator for integer factorization

Many cryptographic algorithms depend on computational complexity assumptions. Notorious cases are the RSA algorithm for public key criptography or the Diffie-Hellman key exchange protocol, to publicly agree on a common secret key. Both algorithms are known to be broken by quantum computing as well as those that can be reduced to a discrete logarithm problem. These are key algorithms in our digital society and are at the basis of everyday tasks, specially those that rely on digital signatures. The RSA algorithm, in particular, is probably the most used algorithm and is its assumed security the one that guards most of the e-commerce nowadays. In this case, it is the time complexity of finding the prime factors of a large number, that grows worse than polinomially with the size of the number, the main guardian of our cyberinfrastructure. The fact that a quantum computer can solve this problem in polynomial time using Shor's algorithm is seen as a potentially major disruption and has prompted security agencies to advice the progressive deprecation of these algorithms