18 resultados para Agro-biodiversity

em Universidad Politécnica de Madrid


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A total of 106 potential duplicate cases involved 277 accessions were detected on the basis of passport data in the durum wheat collection maintained in the CRF-INIA. Similarity between accessions was measured by agro-morphological traits. The 90% of the agro-morphological duplication were verified with gliadin proteins, allowing identification of similar material with greater refinement than agro-morphological data. However, the results indicated not to decide for rationalisation only on the basis of molecular data.

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A total of 106 potential duplicate cases involved 277 accessions were detected on the basis of passport data in the durum wheat collection maintained in the CRF-INIA. Similarity between accessions was measured by agro-morphological traits. The 90% of the agro-morphological duplication were verified with gliadin proteins, allowing identification of similar material with greater refinement than agro-morphological data. However, the results indicated not to decide for rationalisation only on the basis of molecular data

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The authors are from UPM and are relatively grouped, and all have intervened in different academic or real cases on the subject, at different times as being of different age. With precedent from E. Torroja and A. Páez in Madrid Spain Safety Probabilistic models for concrete about 1957, now in ICOSSAR conferences, author J.M. Antón involved since autumn 1967 for euro-steel construction in CECM produced a math model for independent load superposition reductions, and using it a load coefficient pattern for codes in Rome Feb. 1969, practically adopted for European constructions, giving in JCSS Lisbon Feb. 1974 suggestion of union for concrete-steel-al.. That model uses model for loads like Gumbel type I, for 50 years for one type of load, reduced to 1 year to be added to other independent loads, the sum set in Gumbel theories to 50 years return period, there are parallel models. A complete reliability system was produced, including non linear effects as from buckling, phenomena considered somehow in actual Construction Eurocodes produced from Model Codes. The system was considered by author in CEB in presence of Hydraulic effects from rivers, floods, sea, in reference with actual practice. When redacting a Road Drainage Norm in MOPU Spain an optimization model was realized by authors giving a way to determine the figure of Return Period, 10 to 50 years, for the cases of hydraulic flows to be considered in road drainage. Satisfactory examples were a stream in SE of Spain with Gumbel Type I model and a paper of Ven Te Chow with Mississippi in Keokuk using Gumbel type II, and the model can be modernized with more varied extreme laws. In fact in the MOPU drainage norm the redacting commission acted also as expert to set a table of return periods for elements of road drainage, in fact as a multi-criteria complex decision system. These precedent ideas were used e.g. in wide Codes, indicated in symposia or meetings, but not published in journals in English, and a condensate of contributions of authors is presented. The authors are somehow involved in optimization for hydraulic and agro planning, and give modest hints of intended applications in presence of agro and environment planning as a selection of the criteria and utility functions involved in bayesian, multi-criteria or mixed decision systems. Modest consideration is made of changing in climate, and on the production and commercial systems, and on others as social and financial.

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The effect of biodiversity on the ability of parasites to infect their host and cause disease (i.e. disease risk) is a major question in pathology, which is central to understand the emergence of infectious diseases, and to develop strategies for their management. Two hypotheses, which can be considered as extremes of a continuum, relate biodiversity to disease risk: One states that biodiversity is positively correlated with disease risk (Amplification Effect), and the second predicts a negative correlation between biodiversity and disease risk (Dilution Effect). Which of them applies better to different host-parasite systems is still a source of debate, due to limited experimental or empirical data. This is especially the case for viral diseases of plants. To address this subject, we have monitored for three years the prevalence of several viruses, and virus-associated symptoms, in populations of wild pepper (chiltepin) under different levels of human management. For each population, we also measured the habitat species diversity, host plant genetic diversity and host plant density. Results indicate that disease and infection risk increased with the level of human management, which was associated with decreased species diversity and host genetic diversity, and with increased host plant density. Importantly, species diversity of the habitat was the primary predictor of disease risk for wild chiltepin populations. This changed in managed populations where host genetic diversity was the primary predictor. Host density was generally a poorer predictor of disease and infection risk. These results support the dilution effect hypothesis, and underline the relevance of different ecological factors in determining disease/infection risk in host plant populations under different levels of anthropic influence. These results are relevant for managing plant diseases and for establishing conservation policies for endangered plant species.

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Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as rega rds biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the ?Bosque de Neblina de Cuyas?, in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.

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The engineering careers models were diverse in Europe, and are adopting now in Spain the Bolonia process for European Universities. Separated from older Universities, that are in part technically active, Civil Engineering (Caminos, Canales y Puertos) started at end of 18th century in Spain adopting the French models of Upper Schools for state civil servants with exam at entry. After 1800 intense wars, to conserve forest regions Ingenieros de Montes appeared as Upper School, and in 1855 also the Ingenieros Agrónomos to push up related techniques and practices. Other Engineers appeared as Upper Schools but more towards private factories. These ES got all adapted Lower Schools of Ingeniero Tecnico. Recently both grew much in number and evolved, linked also to recognized Professions. Spanish society, into European Community, evolved across year 2000, in part highly well, but with severe discordances, that caused severe youth unemployment with 2008-2011 crisis. With Bolonia process high formal changes step in from 2010-11, accepted with intense adaptation. The Lower Schools are changing towards the Upper Schools, and both that have shifted since 2010-11 various 4-years careers (Grado), some included into the precedent Professions, and diverse Masters. Acceptation of them to get students has started relatively well, and will evolve, and acceptation of new grades for employment in Spain, Europe or outside will be essential. Each Grado has now quite rigid curricula and programs, MOODLE was introduced to connect pupils, some specific uses of Personal Computers are taught in each subject. Escuela de Agronomos centre, reorganized with its old name in its precedent buildings at entrance of Campus Moncloa, offers Grados of Agronomic Engineering and Science for various public and private activities for agriculture, Alimentary Engineering for alimentary activities and control, Agro-Environmental Engineering more related to environment activities, and in part Biotechnology also in laboratories in Campus Monte-Gancedo for Biotechnology of Plants and Computational Biotechnology. Curricula include Basics, Engineering, Practices, Visits, English, ?project of end of career?, Stays. Some masters will conduce to specific professional diploma, list includes now Agro-Engineering, Agro-Forestal Biotechnology, Agro and Natural Resources Economy, Complex Physical Systems, Gardening and Landscaping, Rural Genie, Phytogenetic Resources, Plant Genetic Resources, Environmental Technology for Sustainable Agriculture, Technology for Human Development and Cooperation.

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Nearly 3000 slaughterhouses (74% of them public facilities) were built in Spain during the last decades of the nineteenth century and the first half of the twentieth century. The need to comply with new technical requirements and regulations on the hygiene of the meat passed in the 70s and the gradual replacement of public facilities by larger and more modern private slaughterhouses have subsequently led to the closure and abandonment of many of these buildings. Public slaughterhouses generally consisted of several single-storey and open-plan buildings located around a courtyard. Although originally they were preferably located on the outskirts of the towns, many slaughterhouses are now placed inside the built up areas, due to the urban development. The present work aims to contribute to a better understanding of these agro-industrial buildings and to provide ideas for their conservation and reuse. A review on the historical evolution and the architectural features of the public slaughterhouses in Spain is presented and different examples of old vacant slaughterhouses reused to accommodate libraries, offices, community centres, exhibition halls or sports centres, among others, are shown in the paper.

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La suplementación del ganado en las dehesas supone uno de los mayores costes de producción. En los últimos años el incremento de los precios de las materias primas agrícolas ha sido mayor que el de los productos ganaderos, por lo que muchas explotaciones han reducido sus beneficios. El objetivo de este trabajo es identificar los períodos críticos en la producción de biomasa de pastos de dehesa y en la suplementación por unidad de ganado mayor (UGM). Se ha elaborado un modelo agro-econométrico para estudiar la incidencia de las sequías en el periodo 1999-2010. El modelo se ha validado con datos de campo de tres dehesas de El Cubo de Don Sancho (Salamanca), Trujillo (Cáceres) y Pozoblanco (Córdoba). En una dehesa tipo de Pozoblanco el coste anual medio por suplementación fue de 294,68 ?/UGM, el gasto máximo anual alcanzó los 450,96 ?/UGM en el año 2008/2009 y el mínimo fue de 234,95 ?/UGM el año 2003/2004. La aplicación del modelo ha permitido identificar que los periodos críticos aparecen en mayo, junio, julio y febrero. La sequía prolongada tuvo un impacto económico máximo diario de 1,02 ?/UGM.

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Shrubs play an important role in water-limited agro-silvo-pastoral systems by providing shelter and forage for livestock, for erosion control, to maintain biodiversity, diversifying the landscape, and above all, facilitating the regeneration of trees. Furthermore, the carbon sink capacity of shrubs could also help to mitigate the effects of climate change since they constitute a high proportion of total plant biomass. The contribution of two common extensive native shrub species (Cistus ladanifer L. and Retama sphaerocarpa (L.) Boiss.) to the carbon pool of Iberian dehesas (Mediterranean agro-silvo-pastoral systems) is analyzed through biomass models developed at both individual (biovolume depending) and community level (height and cover depending). The total amount of carbon stored in these shrubs, including above- and belowground biomass, ranges from 1.8 to 11.2 Mg C ha_1 (mean 6.8 Mg C ha_1) for communities of C. ladanifer and from 2.6 to 8.6 Mg C ha_1 (mean 4.5 Mg C ha_1) for R. sphaerocarpa. These quantities account for over 20e30% of the total plant biomass in the system. The potential for carbon sequestration of these shrubs in the studied system ranges 0.10e1.32 Mg C ha_1 year_1 and 0.25e1.25 Mg C ha_1 year_1 for the C. ladanifer and R. sphaerocarpa communities’ respectively

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El objetivo de este trabajo es determinar la influencia de la incorporación de nanoSiO2 y nanoAl2O3 sobre las propiedades macroestructurales de resistencia, dureza superficial y abrasión en morteros de cemento. Para ello se ha determinado la resistencia a compresión, la dureza Vickers y el coeficiente de Los Angeles en cuatro dosificaciones de mortero de cemento CEM I 52,5R, con una relación agua/material cementante de 0.47. Las dosificaciones ensayadas fueron la de un mortero normalizado a la que se añade un 5% de nSi, un 5% de nAl y una adición mezcla de 2,5% de nSi y 2,5% de nAl. Se utilizo un mortero normalizado sin adición como control. Los resultados confirman que, aunque no hay diferencias significativas en las resistencias a compresión, hay un aumento considerable de la dureza superficial Vickers en el mortero con un 5% de la adición de nSi. Esto es debido a una densificación de la matriz por un refinamiento de la estructura porosa y una reducción del tamaño de poro crítico. Sin embargo los resultados de desgaste no presentan diferencias significativas entre los morteros estudiados. Sin embargo, los coeficientes de Los Ángeles están alrededor de 8,85, lo que les clasifica como materiales con buen comportamiento al desgaste.

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Con objeto de mejorar las prestaciones de los materiales y en particular los materiales de construcción, se está estudiando la incorporación de nano partículas en la fabricación de morteros y hormigones. En este trabajo se estudia el efecto en la durabilidad de un hormigón autocompactante al incorporar nanosílice. Para ello se han seleccionado dos dosificaciones de nano sílice, 2,5% y 5% y se ha comparado su comportamiento con un hormigón autocompactante con la misma relación de material cementante. Se han evaluado las diferencias de comportamiento tanto en estado fresco como endurecido. En el trabajo se ha analizado el comportamiento mecánico (resistencia a compresión), microestructural (porosimetría por intrusión de mercurio, análisis termogravimétrico y micrografía) y durable, (migración de cloruros, difusión de cloruros y resistividad eléctrica), de las dosificaciones seleccionadas. Los resultados de los ensayos de resistencia a compresión muestran una relación directa entre éste parámetro y el porcentaje de nano sílice adicionada. Los resultados de la caracterización microestructural ponen de manifiesto un refinamiento de la matriz porosa, con aumento de la cantidad de geles hidratados y reducción del tamaño de poro, más significativo cuanto mayor es el porcentaje de adición. Las imágenes de SEM revelan cambios en la morfología de los productos hidratados de la matriz cementicia. Se observa un aumento significativo de la resistencia del material a la penetración de cloruros cuando se incorpora la nano sílice. Los coeficientes tanto de migración como de difusión de cloruros se reducen a menos de la mitad con la adición del 2,5% de nano sílice, no existiendo diferencias significativas en dichos coeficientes en las mezclas con 2,5% y 5% de nano adición. La resistividad eléctrica se revela como un parámetro que si bien sigue la misma tendencia que el coeficiente de migración , el orden de magnitud de las variaciones entre las distintas dosificaciones existen diferencias significativas.

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La gestión de hábitat orientada a la conservación de polinizadores en los agro-ecosistemas requiere una selección de especies vegetales atendiendo fundamentalmente a dos criterios: i) el potencial atractivo de sus flores a los polinizadores; y ii) la simplicidad en su manejo agronómico. Además de estas premisas, es necesario considerar la capacidad invasora de estas especies vegetales, debido a que algunas de las más atractivas pueden resultar invasoras en determinados agro-ecosistemas. Por lo tanto, es preciso determinar qué especies vegetales son las más indicadas para ser implementadas en cada agro-ecosistema. En la presente tesis doctoral se plantea la búsqueda de las especies vegetales adecuadas para atraer polinizadores en los agro-ecosistemas del centro de España. En una primera aproximación, se ha evaluado la atracción y expansión espacial (potencial invasivo) de seis plantas perennes de la familia Lamiaceae (aromáticas), elegidas por ser nativas de la región mediterránea. La elección de las especies vegetales se ha llevado a cabo con el fin de crear márgenes funcionales basados en la mezcla de especies vegetales con distintos periodos de floración, de modo que prolonguen la disponibilidad de recursos florales en el tiempo. Tras un primer año dedicado al establecimiento de las especies aromáticas, en los dos años siguientes se ha estudiado la atracción individual y combinada de las especies vegetales sobre los polinizadores, y como ésta se ve afectada por la densidad y la morfología floral, utilizando para ello un diseño experimental en bloques al azar. Los resultados de este estudio han puesto de manifiesto que la morfología floral no tuvo influencia sobre la atracción de las especies vegetales, pero si la densidad floral, puesto que las especies vegetales con mayor densidad de flores (Nepeta tuberosa e Hyssopus officinalis) han mostrado mayor atracción a polinizadores. Cabe destacar que de las seis especies consideradas, dos especies de verano (Melissa officinalis y Thymbra capitata) no han contribuido de forma efectiva a la atracción de la mezcla hacia los polinizadores, mostrando una reducción significativa de este parámetro respecto a las otras especies aromáticas a lo largo del verano. Se ha observado que ninguna de las especies aromáticas evaluadas ha mostrado tendencia invasora a lo largo del estudio. En base a estos resultados, se puede concluir que entre las especies aromáticas estudiadas, N. tuberosa, H. officinalis y Salvia verbenaca son las que ofrecen mayor potencial para ser utilizadas en la conservación de polinizadores. De forma similar al caso de las plantas aromáticas, se ha llevado a cabo una segunda experimentación que incluía doce plantas anuales con floración de primavera, en la que se evaluó la atracción a polinizadores y su comportamiento agronómico. Este estudio con especies herbáceas se ha prolongado durante dos años, utilizando un diseño experimental de bloques aleatorios. Las variables analizadas fueron: el atractivo de las distintas especies vegetales a los polinizadores, su eficiencia de atracción (calculada como una combinación de la duración de la floración y las visitas de insectos), su respuesta a dos tipos de manejo agronómico (cultivo en mezcla frente a monocultivo; laboreo frente a no-laboreo) y su potencial invasivo. Los resultados de esta segunda experimentación han mostrado que las flores de Borago officinalis, Echium plantagineum, Phacelia tanacetifolia y Diplotaxis tenuifolia son atractivas a las abejas, mientras que las flores de Calendula arvensis, Coriandrum sativum, D. tenuifolia y Lobularia maritima son atractivas a los sírfidos. Con independencia del tipo de polinizadores atraídos por cada especie vegetal, se ha observado una mayor eficiencia de atracción en parcelas con monocultivo de D. tenuifolia respecto a las parcelas donde se cultivó una mezcla de especies herbáceas, si bien en estas últimas se observó mayor eficiencia de atracción que en la mayoría de parcelas mono-específicas. Respecto al potencial invasivo de las especies herbáceas, a pesar de que algunas de las más atractivas a polinizadores (P. tanacetifolia and C. arvensis) mostraron tendencia a un comportamiento invasor, su capacidad de auto-reproducción se vio reducida con el laboreo. En resumen, D. tenuifolia es la única especie que presentó una alta eficiencia de atracción a distintos tipos de polinizadores, conjuntamente con una alta capacidad de auto-reproducción pero sin mostrar carácter invasor. Comparando el atractivo de las especies vegetales utilizadas en este estudio sobre los polinizadores, D. tenuifolia es la especie más recomendable para su cultivo orientado a la atracción de polinizadores en agro-ecosistemas en el centro de España. Esta especie herbácea, conocida como rúcula, tiene la ventaja añadida de ser una especie comercializada para el consumo humano. Además de su atractivo a polinizadores, deben considerarse otros aspectos relacionados con la fisiología y el comportamiento de esta especie vegetal en los agro-ecosistemas antes de recomendar su cultivo. Dado que el cultivo en un campo agrícola de una nueva especie vegetal implica unos costes de producción, por ejemplo debidos a la utilización de agua de riego, es necesario evaluar el incremento en dichos costes en función de demanda hídrica específica de esa especie vegetal. Esta variable es especialmente importante en zonas dónde se presentan sequías recurrentes como es el caso del centro y sur-este de la península Ibérica. Este razonamiento ha motivado un estudio sobre los efectos del estrés hídrico por sequía y el estrés por déficit moderado y severo de riego sobre el crecimiento y floración de la especie D. tenuifolia, así como sobre la atracción a polinizadores. Los resultados muestran que tanto el crecimiento y floración de D. tenuifolia como su atracción a polinizadores no se ven afectados si la falta de riego se produce durante un máximo de 4 días. Sin embargo, si la falta de riego se extiende a lo largo de 8 días o más, se observa una reducción significativa en el crecimiento vegetativo, el número de flores abiertas, el área total y el diámetro de dichas flores, así como en el diámetro y longitud del tubo de la corola. Por otro lado, el estudio pone de manifiesto que un déficit hídrico regulado permite una gestión eficiente del agua, la cual, dependiendo del objetivo final del cultivo de D. tenuifolia (para consumo o solo para atracción de polinizadores), puede reducir su consumo entre un 40 y un 70% sin afectar al crecimiento vegetativo y desarrollo floral, y sin reducir significativamente el atractivo a los polinizadores. Finalmente, esta tesis aborda un estudio para determinar cómo afecta el manejo de hábitat a la producción de los cultivos. En concreto, se ha planteado una experimentación que incluye márgenes mono-específicos y márgenes con una mezcla de especies atractivas a polinizadores, con el fin de determinar su efecto sobre la producción del cultivo de cilantro (C. sativum). La elección del cultivo de cilantro se debe a que requiere la polinización de insectos para su reproducción (aunque, en menor medida, puede polinizarse también por el viento), además de la facilidad para estimar su producción en condiciones semi-controladas de campo. El diseño experimental consistía en la siembra de márgenes mono-específicos de D. tenuifolia y márgenes con mezcla de seis especies anuales situados junto al cultivo de cilantro. Estos cultivos con márgenes florales fueron comparados con controles sin margen floral. Además, un segundo grupo de plantas de cilantro situadas junto a todos los tratamientos, cuyas flores fueron cubiertas para evitar su polinización, sirvió como control para evaluar la influencia de los polinizadores en la producción del cultivo. Los resultados muestran que la presencia de cualquiera de los dos tipos de margen floral mejora el peso y el porcentaje de germinación de las semillas de cilantro frente al control sin margen. Si se comparan los dos tipos de margen, se ha observado un mayor número de semillas de cilantro junto al margen con mezcla de especies florales respecto al margen mono-específico, probablemente debido al mayor número visitas de polinizadores. Puesto que el experimento se realizó en condiciones de campo semi-controladas, esto sugiere que las visitas de polinizadores fueron el factor determinante en los resultados. Por otro lado, los resultados apuntan a que la presencia de un margen floral (ya sea mono-especifico o de mezcla) en cultivos de pequeña escala puede aumentar la producción de cilantro en más de un 200%, al tiempo que contribuyen a la conservación de los polinizadores. ABSTRACT Habitat management, aimed to conserve pollinators in agro-ecosystems, requires selection of the most suitable plant species in terms of their attractiveness to pollinators and simplicity of agronomic management. However, since all flowers are not equally attractive to pollinators and many plant species can be weedy or invasive in the particular habitat, it is important to test which plant species are the most appropriate to be implemented in specific agro-ecosystems. For that reason, this PhD dissertation has been focused on determination of the most appropriate aromatic and herbaceous plants for conservation of pollinators in agro-ecosystems of Central Spain. Therefore, in a first approximation, spatial expansion (i.e. potential weediness) and attractiveness to pollinators of six aromatic perennial plants from the Lamiaceae family, native and frequent in the Mediterranean region, were evaluated. Preliminary plant selection was based on designing a functional mixed margins consisting of plants attractive to pollinators and with different blooming periods, in order to extend the availability of floral resources in the field. After a year of vegetative growth, the next two years the plant species were studied in a randomized block design experiment in order to estimate their attractiveness to pollinators in Central Spain and to investigate whether floral morphology and density affect attractiveness to pollinators. The final aim of the study was to evaluate how their phenology and attractiveness to pollinators can affect the functionality of a flowering mixture of these plants. In addition, the spatial expansion, i.e. potential weediness, of the selected plant species was estimated under field conditions, as the final purpose of the studied plants is to be implemented within agro-ecosystems. The results of the experiment showed that floral morphology did not affect the attractiveness of plants to pollinators, but floral density did, as plant species with higher floral density (i.e. Nepeta tuberosa and Hyssopus officinalis) showed significantly higher attractiveness to pollinators. In addition, of six plant species, two summer species (Melissa officinalis and Thymbra capitata) did not efficiently contribute to the attractiveness of the mixture to pollinators, which reduced its attractiveness during the summer period. Finally, as none of the plants showed weedy behaviour under field conditions, the attractive plant species, i.e. N. tuberosa, H. officinalis and the early spring flowering Salvia verbenaca, showed good potential to conserve the pollinators. Similarly, in a second approximation, the attractiveness to pollinators and agronomic behaviour of twelve herbaceous plants blooming in spring were studied. This experiment was conducted over two years in a randomized block design in order to evaluate attractiveness of preselected plant species to pollinators, as well as their attractiveness efficiency (a combination of duration of flowering and insect visitation), their response to two different agronomic management practices (growing in mixed vs. mono-specific plots; tillage vs. no-tillage), and their potential weediness. The results of this experiment showed that the flowers of Borago officinalis, Echium plantagineum, Phacelia tanacetifolia and Diplotaxis tenuifolia were attractive to bees, while Calendula arvensis, Coriandrum sativum, D. tenuifolia and Lobularia maritima were attractive to hoverflies. In addition, floral mixture resulted in lower attractiveness efficiency to pollinators than mono-specific D. tenuifolia, but higher than most of the mono-specific stands. On the other hand, although some of the most attractive plant species (e.g. P. tanacetifolia and C. arvensis) showed potential weediness, their self-seeding was reduced by tillage. After comparing attractiveness efficiency of various herbaceous species to pollinators and their potential weediness, the results indicated that D. tenuifolia showed the highest attractiveness efficiency to pollinators and efficient self-reproduction, making it highly recommended to attract bees and hoverflies in agro-ecosystems of Central Spain. In addition, this plant, commonly known as wild rocket, has a supplementary economic value as a commercialized crop. The implementation of a new floral margin in agro-ecosystems means increased production costs, especially in regions with frequent and long droughts (as it is Central and South-East area of Iberian Peninsula), where the principal agricultural cost is irrigation. Therefore, before recommending D. tenuifolia for sustainable habitat management within agro-ecosystems, it is necessary to study the effect of drought stress and moderate and severe deficit irrigation on its growth, flower development and attractiveness to pollinators. The results of this experiment showed that in greenhouse conditions, potted D. tenuifolia could be without irrigation for 4 days without affecting its growth, flowering and attractiveness to pollinators. However, lack of irrigation for 8 days or longer significantly reduced the vegetative growth, number of open flowers, total floral area, flower diameter, corolla tube diameter and corolla tube length of D. tenuifolia. This study showed that regulated deficit irrigation can improve water use efficiency, and depending on the purpose of growing D. tenuifolia, as a crop or as a beneficial plant to attract pollinators, it can reduce water consumption by 40% to 70% without affecting its vegetative and floral development and without reducing its attractiveness to pollinators. Finally, the following experiment was developed in order to understand how habitat management can influence on the agricultural production. For this purpose, it was evaluated if the vicinity of mixed and mono-specific field margins, preselected to conserve pollinators within agro-ecosystems, can improve seed production in coriander (C. sativum). The selection of this plant species for the experiment was based on its necessity for insect pollination for production of seeds (even though some pollen can be transmitted from one flower to another by wind) and the fact that under semi-controlled field conditions established in the field it is possible to estimate its total seed production. Since D. tenuifolia is attractive for both bees and hoverflies in Central Spain, the main objective of this experiment was to estimate the impact of two different types of field margins, i.e. mono-specific margin with D. tenuifolia and mixed margin with six herbaceous species, on the seed production of potted coriander. For that reason, it was tested: i) if open pollination (control without proximate field margin and treatments with nearby mono-specific and mixed margin) increases the seed production of coriander when compared with no-pollination (covered inflorescences of coriander) under field conditions; ii) if frequency of pollinator visitation to the flowers of coriander was higher in the presence of field margins than in the control without field margin; and iii) if seed production was higher in the presence of field margins than in control plants of coriander without field margin. The results showed that the proximity of both types of floral margins (mixed and mono-specific) improved the seed quality of coriander plants, as seed weight and germination rate were higher than in control plants without field margin. Furthermore, the number of seeds produced was significantly higher in coriander plants grown near mixed margins than near mono-specific margin, probably due to an increase in pollinator visits. Since the experiment was conducted under semi-controlled field conditions, it can be concluded that pollinator visits was the main factor that biased the results, and that presence of both mixed or mono-specific (D. tenuifolia) margins can improve the production of coriander for more than 200% in small-scale gardens and, in addition, conserve the local pollinators.

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En el presente trabajo se ha llevado a cabo un estudio de la biodiversidad del frijol común (Phaseolus vulgaris L.) en Honduras, que es el segundo de los cultivos de granos básicos en importancia. Dicho estudio se ha realizado mediante una caracterización agromorfológica, molecular y ecogeográfica en una selección de 300 accesiones conservadas en el banco de germoplasma ubicado en la Escuela Agrícola Panamericana (EAP) El Zamorano, y que se colectaron en 13 departamentos del país durante el periodo de 1990 a 1994. Estas accesiones fueron colectadas cuatro años antes del acontecimiento del huracán Mitch, el cual a su paso afectó al 96% del área total cultivable en su momento, lo cual nos hace considerar que la biodiversidad de razas locales (landraces) de frijol común existentes in situ fueron severamente afectadas. Los trabajos dirigidos a analizar la biodiversidad de razas locales de frijol común en Honduras son escasos, y este trabajo se constituye como el primero que incluye una amplia muestra a ser estudiada a través de una caracterización en tres aspectos complementarios (agromorfológico, molecular y ecogeográfico). Se evaluaron 32 caracteres agromorfológicos, 12 cuantitativos y 20 cualitativos, en distintas partes de la planta. Se establecieron las correlaciones entre los caracteres agromorfológicos y se elaboró un dendrograma con los mismos, en el que se formaron ocho grupos, en parte relacionados principalmente con los colores y tamaños de la semilla. Mediante el análisis de componentes principales se estudiaron los caracteres de más peso en cada uno de los tres primeros componentes. Asimismo, se estudiaron las correlaciones entre caracteres, siendo las más altas la longitud y anchura de la hoja, días a madurez y a cosecha y longitud y peso de semilla. Por otra parte, el mapa de diversidad agromorfológica mostró la existencia de tres zonas con mayor diversidad: en el oeste (en los departamentos de Santa Bárbara, Lempira y Copán), en el centro-norte (en los departamentos de Francisco Morazán, Yoro y Atlántida) y en el sur (en el departamento de El Paraíso y al sur de Francisco Morazán). Para la caracterización molecular partimos de 12 marcadores de tipo microsatélite, evaluados en 54 accesiones, que fueron elegidas por constituir grupos que compartían un mismo nombre local. Finalmente, se seleccionaron los cuatro microsatélites (BM53, GATS91, BM211 y PV-AT007) que resultaron ser más polimórficos e informativos para el análisis de las 300 accesiones, con los que se detectaron un total de 119 alelos (21 de ellos únicos o privados de accesión) y 256 patrones alélicos diferentes. Para estudiar la estructura y relaciones genéticas en las 300 accesiones se incluyeron en el análisis tres controles o accesiones de referencia, pertenecientes dos de ellas al acervo genético Andino y una al Mesoamericano. En el dendrograma se obtuvieron 25 grupos de accesiones con idénticas combinaciones de alelos. Al comparar este dendrograma con el de caracteres agromorfológicos se observaron diversos grupos con marcada similitud en ambos. Un total de 118 accesiones resultaron ser homogéneas y homocigóticas, a la vez que representativas del grupo de 300 accesiones, por lo que se analizaron con más detalle. El análisis de la estructura genética definió la formación de dos grupos, supuestamente relacionados con los acervos genéticos Andino (48) y Mesoamericano (61), y un reducido número de accesiones (9) que podrían tener un origen híbrido, debido a la existencia de un cierto grado de introgresión entre ambos acervos. La diferenciación genética entre ambos grupos fue del 13,3%. Asimismo, 66 de los 82 alelos detectados fueron privados de grupo, 30 del supuesto grupo Andino y 36 del Mesoamericano. Con relación al mapa de diversidad molecular, presentó una distribución bastante similar al de la diversidad agromorfológica, detectándose también las zonas de mayor diversidad genética en el oeste (en los departamentos de Lempira y Santa Bárbara), en el centro-norte (en los departamentos de Yoro y Atlántida) y en el sur (en el departamento de El Paraíso y al sur de Francisco Morazán). Para la caracterización ecogeográfica se seleccionaron variables de tipo bioclimático (2), geofísico (2) y edáfico (8), y mediante el método de agrupamiento de partición alrededor de los medoides, la combinación de los grupos con cada uno de los tres tipos de variables definió un total de 32 categorías ecogeográficas en el país, detectándose accesiones en 16 de ellas. La distribución de las accesiones previsiblemente esté relacionada con la existencia de condiciones más favorables al cultivo de frijol. En el mapa de diversidad ecogeográfica, nuevamente, se observaron varias zonas con alta diversidad tanto en el oeste, como en el centro-norte y en el sur del país. Como consecuencia del estudio realizado, se concluyó la existencia de una marcada biodiversidad en el material analizado, desde el punto de vista tanto agromorfológico como molecular. Por lo que resulta de gran importancia plantear la conservación de este patrimonio genético tanto ex situ, en bancos de germoplasma, como on farm, en las propias explotaciones de los agricultores del país, siempre que sea posible. ABSTRACT In the present work we have carried out a study of the biodiversity of the common bean (Phaseolus vulgaris L) in Honduras, which is the second of the basic grain crops in importance. This study was conducted through agro-morphological, molecular and ecogeographical characterization of a selection of 300 accessions conserved in the genebank located in the ‘Escuela Agrícola Panamericana (EAP) El Zamorano’ that were collected in 13 departments of the country during the 1990 to 1994 period. These accessions were collected four years before the occurrence of Mitch hurricane, which affected 96% of the total cultivable area at the time, which makes us to consider that the biodiversity of local landraces of common bean existing in situ were severely affected. The work aimed to analyze the biodiversity of local races of common bean in Honduras are scarce, and this work constitutes the first to include a large sample to be studied through a characterization on three complementary aspects (agromorphological, molecular and ecogeographical). Thirty two agromorphological characters, 12 quantitative and 20 qualitative, in various parts of the plant were evaluated. Correlations between agromorphological characters were established and a dendrogram with them was constructed, in which eight groups were formed, in part mainly related to the colors and sizes of the seeds. By principal component analysis the characters with more weight in each of the first three components were studied. Also, correlations between characters were studied, the highest of them being length and leaf width, days to maturity and harvest, and seed length and weight. Moreover, the map of agromorphological diversity showed the existence of three areas with more diversity: the west (departments of Santa Barbara, Copan and Lempira), the center-north (departments of Francisco Morazán, Yoro and Atlántida) and the south (department of El Paraiso and south of Francisco Morazán). For molecular characterization we started with 12 microsatellite markers, evaluated in 54 accessions, which were chosen because they formed groups that shared the same local name. Finally, four microsatellites (BM53, GATS91, BM211 and PV-AT007) were selected for the analysis of 300 accessions, since they were the most polymorphic and informative. They gave a total of 119 alleles (21 of them unique or private for the accession) and 256 different allelic patterns. To study the structure and genetic relationships in the 300 accessions, three controls or accessions of reference were included in the analysis: two of them belonging to the Andean gene pool and one to the Mesoamerican. In the dendrogram, 25 accession groups with identical allele combinations were obtained. Comparing this dendrogram to the obtained with agromorphological characters, several groups with marked similarity in both were observed. A total of 118 accessions were homozygous and homogeneous, while representing the group of 300 accessions, therefore they were analyzed in more detail. The analysis of the genetic structure defined the formation of two groups, supposedly related to the Andean (48) and the Mesoamerican (61) gene pools, and a small number of accessions (9) which may have a hybrid origin, due to the existence of some degree of introgression between both gene pools. Genetic differentiation between both groups was 13.3%. Also, 66 of the 82 detected alleles were private or unique for the group, 30 of the supposed Andean group and 36 of the Mesoamerican. With relation to the map of molecular diversity, it showed a quite similar distribution to the agromorphological, also detecting the areas of greatest genetic diversity in the west (departments of Lempira and Santa Bárbara), in the center-north (departments Atlántida and Yoro) and in the south (departments of El Paraíso and south of Francisco Morazán). For the ecogeographical characterization, bioclimatic (2), geophysical (2) and edaphic (8) variables were selected, and by the method of clustering partition around the medoids, the combination of the groups to each of the three types of variables defined a total of 32 ecogeographical categories in the country, having accessions in 16 of them. The distribution of accessions is likely related to the existence of more favorable conditions for the cultivation of beans. The map of ecogeographical diversity, again, several areas with high diversity both in the west and in the center-north and in the south of the country were observed. As a result of study, the existence of marked biodiversity in the analyzed material was concluded, both from the agromorphological and from the molecular point of view. Consequently it is very important to propose the conservation of this genetic heritage both ex situ, in genebanks, as on farm, in the holdings of the farmers of the country, whenever possible.

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Abstract In this paper we examine the trends of nitrous oxide (N2O) emissions of the Spanish agricultural sector related to national production and consumption in the 1961?2009 period.The comparison between production- and consumption-based emissions at the national level provides a complete overview of the actual impact resulting from the dietary choices of a given country and allows the evaluation of potential emission leakages. On average, 1.5 % of the new reactive nitrogen that enters Spain every year is emitted as N2O. Production- and consumption-based emissions have both significantly increased in the period studied and nowadays consumption-based emissions are 45 % higher than production-based emissions. A large proportion of the net N2O emissions associated with imported agricultural godos comes from countries that are not committers for the United Nations Framework Convention on Climate Change Kyoto Protocol Annex I. An increase in feed consumption is the main driver of the changes observed, leading to a arkable emission leakage in the Spanish agricultural sector. The complementary approach used here is essential to achieve an effective mitigation of Spanish greenhouse gas emissions.

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Carbon (C) and nitrogen (N) process-based models are important tools for estimating and reporting greenhouse gas emissions and changes in soil C stocks. There is a need for continuous evaluation, development and adaptation of these models to improve scientific understanding, national inventories and assessment of mitigation options across the world. To date, much of the information needed to describe different processes like transpiration, photosynthesis, plant growth and maintenance, above and below ground carbon dynamics, decomposition and nitrogen mineralization. In ecosystem models remains inaccessible to the wider community, being stored within model computer source code, or held internally by modelling teams. Here we describe the Global Research Alliance Modelling Platform (GRAMP), a web-based modelling platform to link researchers with appropriate datasets, models and training material. It will provide access to model source code and an interactive platform for researchers to form a consensus on existing methods, and to synthesize new ideas, which will help to advance progress in this area. The platform will eventually support a variety of models, but to trial the platform and test the architecture and functionality, it was piloted with variants of the DNDC model. The intention is to form a worldwide collaborative network (a virtual laboratory) via an interactive website with access to models and best practice guidelines; appropriate datasets for testing, calibrating and evaluating models; on-line tutorials and links to modelling and data provider research groups, and their associated publications. A graphical user interface has been designed to view the model development tree and access all of the above functions.