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Resumo La estabilidad atmosférica en la capa superficial, influye en muchos de los procesos dinámicos que se dan en la atmósfera, afectan los fenómenos de difusión y transporte de energía y materia, razón por lo que se ha estudiado ampliamente en latitudes medias; sin embargo, existen muy pocos trabajos en condiciones típicas del altiplano ecuatoriano (latitud cero y altura media respecto al nivel del mar de alrededor de 2500 m). En el presente trabajo se desarrolla un estudio de la variación de la estabilidad atmosférica en dichas condiciones, usado datos de la estación meteorológica de la Universidad Nacional de Chimborazo del año 2015. Los resultados obtenidos en este estudio muestran un predominio del estado muy estable durante la noche y entre muy inestable e inestable durante el día según la clasificación de Pasquill, con un comportamiento medio mensual regular a lo largo del año. Abstract The atmospheric stability in the surface layer, influences many of the dynamic processes that occur in the atmosphere, affect the phenomena of diffusion and transport of energy and matter, reason why it has been studied extensively in middle latitudes, however, There are very few jobs in conditions typical of the Ecuadorian highlands (zero latitude and average height with respect to sea level of around 2500 m). In the present work a study of the variation of the atmospheric stability in those conditions is carried out, used data of the meteorological station of the National University of Chimborazo, taken by hours during the year 2015. The results obtained in this study show a predominance of the Very stable during the night and between very unstable and unstable during the day according to the classification of Pasquill, with a regular monthly average behavior throughout the year.

La investigación consiste en el diseño y la implementación de un modelo de clasificación de hidrometeoros basado en firmas de radar meteorológico banda C, aplicable a la región ecuatorial. Inicialmente se realizó la decodificación de los datos nativos de radar, a los cuales se les aplicaron pruebas estadísticas. Posteriormente se determinaron las clases de hidrometeoros que conformaron el sistema de clasificación. Seguidamente fue necesario determinar las variables polarimétricas que aportarían información al modelo teniendo en cuenta las clases de hidrometeoros definidos. Esta decisión se tomó teniendo en cuenta la cantidad de información que cada observable polarimétrico aportó con relación al tipo de hidrometeoro presentado en la región objeto de estudio. A continuación se diseñó un modelo de lógica difusa, que, basado en una técnica de clasificación, recibió las lecturas de radar polarimétrico y entregó como salida el tipo de hidrometeoro presentado en la zona explorada por el rayo de radar. Finalmente el modelo presentado se valido utilizando tanto datos simulados como reales con lo cual se probó la efectividad del clasificador y se generaron las conclusiones de la investigación. The research consists in the design and implementation of a hydrometeor classification model based on C band weather radar signatures, applicable to the equatorial region. Initially, the decoding of the native radar data was performed, to which statistical tests were applied. Subsequently, the classes of hydrometeors that formed the classification system were determined. Next, it was necessary to determine the polarimetric variables that would provide information to the model taking into account the classes of defined hydrometeors. This decision was made taking into account the amount of information that each polarimetric variable contributed in relation to the type of hydrometeor presented in the region under study. Then a fuzzy logic model was designed, which, based on a classification technique, received the polarimetric radar readings and delivered as output the type of hydrometeor presented in the area explored by the radar beam. Finally, the presented model was validated using both simulated and real data, which proved the effectiveness of the classifier and generated the conclusions of the research.

Agroecology aims to design economically and environmentally efficient cropping systems, based on the exploitation of natural regulations. Arbuscular mycorrhiza are of growing interest for such an ecologization of agriculture, as they are likely to provide ecosystem services and enhance crop health and productivity, reducing the use of chemicals. Agroecology no longer offers one-stop solutions but calls for a diversity of solutions that leaves the choice to farmers to build their own trade-offs, relying on their own knowledge, scientific knowledge and available products.

This report presents a concise review of the major environmental and natural resources issues at the global and national level over the coming two decades. The environmental issues reviewed include air pollution and deterioration of air quality, greenhouse gas emissions and climate change, water quality, scarcity and access, land and soil degradation, deforestation and forest degradation, natural disaster, loss of biodiversity and protected areas, and governance and institutions for environmental and natural resource management. Besides providing an environment outlook, the report tackles the issue of monitoring also from the supply side. It identifies the relevant data and indicator sets available at the global level and country level to capture the global and locally relevant environmental issues with the underlying objective of pinpointing at data gaps. It concludes with a set of recommendations for moving forward on the monitoring agenda. Overall, the threats from climate change caused by Green House Gas (GHG) emissions, biodiversity loss, water pollution and scarcity as well as pressure on land as well as worsening ocean's state and biodiversity have to be taken under close observation in the period over the next 20 years. The environment challenges that the world faces are not trivial and some of them require immediate action. Action, in turn, requires reliable and accurate information. The second part of the report looks at information from the supply side. It identifies the relevant data and indicator sets available at the global level and country level to capture the global and locally relevant environmental issues with the underlying objective of informing and advising decision making and to identify the data gaps.

International audience; La zoochorie (transport des graines par les animaux) joue un rôle prépondérant dans les forêts tropicales. L'action de la faune sur la régénération forestière est analysée en fonction des co-évolutions s'étant développées entre plantes et animaux frugivores. Différentes associations entre certains types de fruits et certains groupes de mammifères ou d'oiseaux sont décrites, en insistant sur la spécificité de la dissémination qui en résulte. Celle-ci est le plus souvent hétérogène dans des sites plutôt favorables au développement des plantules. Ces diverses modalités de dissémination concourent autant à la colonisation de sites nouveaux qu'au maintien des espèces végétales dans un environnement donné. Dans le cas des plantes pionnières, la distribution est plus homogène et contribue à alimenter la banque de graines du sol. Ces graines entrent en dormance et ne germeront qu'après une ouverture de la canopée. La chasse des animaux frugivores pourrait avoir de lourdes conséquences pour certaines espèces végétales notamment.