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Article discussing the understory of an Andean cloud forest in the Sierra Nevada National Park, Venezuela.

This report discusses the Assessment of Impacts of Global Climatic Changes on the Venezuelan Agricultural System Workshop, as part of the PAN-EARTH Project, Venezuela case study.

The search for novel forms to generate electricity, renewable and clean, is a priority for today’s society. Renewable energy resources exploited and exploitable in each place are: the ability to produce biomass, position relative to the sun, wind, sea and others. The movement of the sea is a promising source of energy, renewable and clean, but conditions of each place are different, it makes difficult to use just one generation technology for every maritime area, each region has its specific conditions that benefit one to and other technology. This research produced a mathematical and computational model for the extraction of kinetic energy from Sea Waves power, especially for superficial and intermediate depths. The system cost of a float and an arm coupled to an electrical generator, the mathematical model implemented allows the variation of different parameters to assist a glimpse of the possibilities, limitations, advantages and disadvantages of this particular form of generation. ; La búsqueda de nuevas formas de generar electricidad, renovables y limpias, es una prioridad para la sociedad actual. Entre los recursos energéticos renovables explotados y explotables en cada lugar se encuentran: la capacidad de producir biomasa, posición respecto al sol, vientos y el mar entre otros. El movimiento del mar es una fuente promisoria de energía, pero debido a la variación de sus condiciones de un lugar a otro, se hace difícil una unificación tecnológica que sea ´óptima para todas las regiones marítimas de la tierra, cada región tiene sus condiciones particulares que beneficia una u otra tecnología. Este proyecto de investigación modela matemáticamente y computacionalmente un sistema de recuperación de energía movido por el oleaje del mar, especialmente para aguas pandas e intermedias. Este sistema consta de un flotador (boya) y un brazo acoplados a un generador, el modelo matemático implementado permite la variación de los diferentes parámetros ayudando a vislumbrar las posibilidades, restricciones, bondades y ...

Report on the potential impacts of global climate change in the farming systems and terrestrial ecosystems in Venezuela.

The Oaxaca Wind Resource Atlas, produced by the National Renewable Energy Laboratory's (NREL's) wind resource group, is the result of an extensive mapping study for the Mexican State of Oaxaca. This atlas identifies the wind characteristics and distribution of the wind resource in Oaxaca. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications.

Article on canopy gaps and understory light spectrum in a Venezuelan Andean cloud forest.

Nitrogen fertilization is the most costly production factor in wheat cropping systems on Ultisols, one of the most eroded soil types in Southern Chile. The utilization efficiency of N-fertilizer was assessed in a wheat cultivar ( Triticum aestivum L.) growing under three soil tillage systems: Traditional, burning of crop residues/soil plow down (TRAD); no-till/burning (CL+Q), and no-till/no burning (CL-Q). The method used measurements of grain yield, total N uptake by plants and their components: N derived from fertilizer (Nddf) and N derived from soil (Ndds). Physiological N use efficiency, was evaluated for total plant N (EFNt = grain yield/Nddf +Ndds) and for N-fertilizer in plants (EFNf = grain yields/N-fertilizer). 15 N-labelled urea, 10 % atom excess (a.e.) was added to the microplots at the rate of 150 kg N ha -1 . The fertilizer was applied three times: 10% at planting, 45% at tilling and 45% at jointing stage. There were no significant seasonal differences for wheat grain yield among tillage treatments with yield of 6.7 to 7.5 t ha -1 on 1997/1998 and 4.6 to 5.4 t ha -1 on 1998/99 season. The treatments CL+Q in 1997/1998 and TRAD in 1998/1999 had the highest total N uptake. The CL-Q treatment showed lowest N-fertilizer uptake by plants for each season, while keeping similar grain yields as the other two tillage systems. This led to higher physiological nitrogen use efficiency on grain production per unit of N-fertilizer absorbed by plants.

This project presents a model for the collection of used cooking oil as raw material for biodiesel production in Puerto Rico. We propose the use of a user friendly application in Excel, designed to approximately solve the capacitated vehicle routing problem (CVRP). The application gives cost-effective solutions, defines the daily assignment of routes for a fleet of vehicles with different capacities, determines transportation costs, and defines the routes in a timely manner allowing a considerable improvement in the daily planning of this task. This tool is specially tailored to the topography and the speed limits of the roads of Puerto Rico. The objectives of this project is to reduce the cost of biodiesel production by reducing the raw material transportation costs and to reduce the water contamination caused by the residue of the cooking oil by improving the collection planning. ; Este trabajo presenta un modelo de recolección de aceites usados de cocina como materia prima para la fabricación de biodiesel en Puerto Rico. Se propone el uso de una herramienta en Excel fácil de utilizar por cualquier usuario, diseñada para dar una solución aproximada del problema de ruteo de vehículos capacitados (CVRP). Esta aplicación provee soluciones costo- efectivas en la asignación de rutas a visitar diariamente por una flota de vehículos con diversas capacidades, determina los costos de transporte, las rutas satisfaciendo restricciones de tiempo de los conductores, proporcionando así una mejora considerable en la planificación diaria de dicha tarea. La herramienta se adapta especialmente al sistema montañoso y a los límites de velocidad de las carreteras de Puerto Rico. Con la elaboración de este proyecto se pretende reducir los costos de producción del biodiesel disminuyendo los costos de transporte de la materia prima y reducir la contaminación generada por el residuo del aceite usado de cocina en las aguas mejorando la planificación de su recogido. ; 2008

This paper was presented at the 1-2 October, 2009 Conference of the Centre International de Recherches et d'Information sur l'Economie Publique, Sociale et Coopérative (CIRIEC) in Östersund, Sweden. It was subsequently translated into Spanish. ; Spanish translation of an original paper in English. Trans-disciplinary thinking by evolutionary, social, and ecological economists from the mid-1970s pointed to a new paradigm from which working models are emerging. This paper illustrates their relevance to a context where the vulnerability of communities to the intertwined issues of carbon, energy, food, finance, and disparity is mounting. The strategic role of co-operative, complementary innovation in navigating these challenges is elaborated. ; BC-Alberta Social Economy Research Alliance (BALTA) ; Social Sciences and Humanities Research Council of Canada (SSHRC)

Nursery is a stage most important in the productive process of fruit crops. A trial was conducted for analyzed the effect of two types of pack and two substrates on vegetative growth of papaya seedlings. The experiment was made from June to August 2006. The experimental design was randomized completely, four treatments and three replicates. T1 plastic bags (730 ml) and lime loam soil, T2 plastic bags and peat moss, T3 plastic trays of two hundred cavities (20 ml per cavity) and lime loam soil and T4 plastic trays and peat moss. The variables studied were: seedling height, stem diameter, number of leaves photo synthetically active and dry biomass of roots and stem plus leaves of seedlings. Statistical analysis was variance analysis and test Tukey 5 %. Medium values of seedlings height varied from 5.10 to 21.29 cm, stem diameter 3.23 to 6.87 mm, number of leaves 4 to 7, dry biomass stem plus leaves 0.01 to 0.69 g and dry biomass roots 0.01 to 0.48 g. T2 was the highest in all studied variables. Results showed that plastic bags and lime loam soil were more adequate for propagation of papaya seedlings at nursery ; El establecimiento y manejo de la planta en el vivero es una de las etapas más importantes del proceso productivo de los cultivos frutícolas. El objetivo del trabajo fue analizar el efecto de dos tipos de envase y dos sustratos, sobre el desarrollo vegetativo de plántulas de lechosa. La investigación se efectuó de junio a agosto de 2006. El diseño experimental utilizado fue completamente al azar, se usaron dos tipos de envase y dos sustratos, que generaron cuatro tratamientos (T1: Bolsas de polietileno negro (730 ml) y turba de musgo; T2: Bolsas de polietileno negro y suelo franco limoso; T3: Bandejas de plástico negro de 200 cavidades (20 ml por cavidad) y turba de musgo y T4: Bandejas de plástico negro y suelo franco limoso), se emplearon tres repeticiones por tratamiento. Las variables estudiadas fueron: altura de plántula, diámetro de tallo, número de hojas fotosintéticamente activas y biomasa seca de las partes aérea y radical de las plántulas. Los datos se analizaron mediante varianza y comparación de medias Tukey 5 %. La altura de plántula varió de 5,10 a 21,29 cm, diámetro de tallo de 3,23 a 6,87 mm, número de hojas de 4 a 7, masa seca aérea de 0,01 a 0,69 gramos y masa seca radical de 0,01 a 0,48 gramos. El T2 fue superior a los demás tratamientos en todas las variables evaluadas. Con base en los resultados se recomienda el uso de bolsas plásticas y suelo franco limoso, para la propagación de plántulas de lechosa en vivero.