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This article shows the effect that biogases obtained from crop residuals from the Andean region have on the performance of a whole medium-sized electrical-generating gas turbine. This technology could be used to supply electricity in energy-depressed areas where biogas is the only accessible resource. The gas turbine worked with higher efficiencies when the obtained biogases were used compared to natural gas. The biofuel that presented the highest efficiencies was the one obtained from wheat residuals alone. Despite this fact, this biofuel would be the most prone to create aerodynamic problems in the stages of the gas turbine. In this work, it was found that the addition of guinea pig manure to different crop residuals created biofuels less prone to create aerodynamic problems in the compression and expansion stages. In particular, the studied biofuel that had the most similar aerodynamic behavior to the design natural gas case was the one obtained from guinea pig manure and quinoa residuals. On the other hand, this biogas presented the lowest efficiencies of the studied biofuels. Despite this fact, this biofuel showed higher efficiencies than the natural gas case. In the gas turbine combustion chamber, all the studied biofuels operated at lower temperatures than the ones with natural gas, even in the high-power range. This would be an important feature for the running of the combustion chamber and the high-pressure turbine superalloys.

El aprovechamiento de la biomasa con fines energéticos es una alternativa atractiva para reducir la dependencia de los combustibles fósiles y su impacto ambiental. En este sentido, la ubicación geográfica de los sitios de producción y consumo de biomasa, su logística, así como la planificación de la cadena productiva, son factores indispensables para la evaluación y puesta en marcha de proyectos biomásicos con fines energéticos. Aunque diversos estudios han abordado estos problemas de forma separada, son pocos los trabajos que integran todos estos aspectos. En este trabajo se describe la integración de una serie de análisis espaciales, con un modelo matemático para la optimización de costos de transporte entre diferentes nodos de la cadena productiva de la biomasa. Mediante un caso de estudio y el análisis de diferentes escenarios de oferta y demanda, se evalúa el funcionamiento del módulo de optimización. Los resultados obtenidos permiten estimar de manera óptima la distribución de biomasa desde diferentes centros de oferta (nodos de almacenamiento), hacia diferentes usuarios (nodos de demanda), tomando al costo de transporte como función objetivo. La distribución óptima de biomasa permite planificar su uso para diferentes regiones de interés a nivel nacional.

The objective of this research was to evaluate the anaerobic co-digestion of guinea pig manure (CY) with Andean agricultural residues such as amaranth (AM), quinoa (QU) and wheat (TR) in batch biodigesters under mesophilic conditions (37⁰C) for 40 days. As microbial inoculum, sewage treatment sludge was used in two inoculum/substrate ratios (ISR of 1 and 2). In terms of methane production, the best results occurred in the treatments that contained AM and QU as co-substrate and an ISR of 2. Thus, the highest methane production occurred in the CY:AM biodigesters (25:75) and CY:QU (25:75) with 341.86 mlCH4/g VS and 341.05 mlCH4/g VS, respectively. On the other hand, the results showed that methane production with an ISR of 2 was more feasible for guinea pig waste, where the methane fraction of the biogas generated was in a range of 57 and 69%. The kinetics of methane production from these raw materials was studied using five kinetic models: modified Gompertz, logistic equation, transfer, cone, and Richards. The cone model was the one that best adjusted the experimental values ​​with those observed with an r2 of 0.999 and an RMSE of 1.16 mlCH4/g VS. Finally, the highest biodegradability was obtained in the CY-AM biodigesters (25:75) with 67.92%.

The main objective of this research is to separate virgin polymers (PA, PC, PP, HDPE; PS and ABS) and post-consumer plastic waste from municipal solid waste (MSW) using the sinking-flotation technique. The separation was carried out on a pilot scale in a container of 800 l of useful volume with agitation of 160 rpm for one hour. Tap water, ethanol solutions and sodium chloride at different concentrations were used as the densification medium. The virgin polymers were separated into two groups, that is, a group of low-density polymers (HDPE and PP) and a group of high-density polymers (PS, ABS, PA, and PC). Polymers whose density was less than that of the medium solution floated to the surface, while those whose density was greater than that of the medium solution sank to the bottom. The experimental results showed that the complete separation of HDPE from PP was achieved at 23% v/v of ethanol. For the separation of the high-density polymers, up to 40% w / v sodium chloride was used. The recoveries of the polymers ranged from 70 to 99.70%. In post-consumer recycled plastic waste, fractions of 29.6% polyolefins, 37.54% PS, 11% ABS, 8% PA and 12% PC, PET and PVC were obtained. Finally, cast plates were made of the post-consumer waste to improve the identification of the type of polymer present in the separated fractions.

This study aims to evaluate the effects of the co‐digestion of agricultural residues with manure from camelids from the Andean zone. Different combinations of llama manure (LM) and vicuñas (VM) were made with amaranth (AS), quinoa (QS), and wheat (WS) residues. They were fermented using sewage sludge as inoculum. The co‐digestion was evaluated under mesophilic conditions for 40 days. The ratios of volatile substances of substrate / co‐substrate evaluated were 0:100; 25:75; 50:50, 75:25, and 100:0. Two substrate / inoculum ratios (SIR 1:1 and SIR1:2) were also evaluated. The results indicate that the maximum methane accumulation rate is obtained in SIR 1:1 for a VM‐AS ratio (25:75) with 540 mL/g volatile solid (VS). In general, the results did not increase with the increase in inoculum; rather, the tendency to improve methane yield is associated with an increase in the amount of agricultural residues, mainly AS. Regarding the kinetic modeling, the transfer model is the one that best adjusted the predicted values to those observed with an r2 between 0.991 and 0.999, and an RMSE value between 2.06 and 13.62 mL/g (volatile solid) VS. Finally, all the trials presented synergistic effects in their co‐digestion except the digesters formed by LM‐AS, LM‐QS and LM‐WS of SIR 1:2. These presented antagonistic effects in which the addition of the co‐substrate generated competition with the substrates, reducing methane production. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

This study shows the energy potential of pine wood waste for the production of solid biofuels, and was carried out in an indigenous community in the state of Michoacán. One of the main economic activities of this community is the production of handcrafted furniture, which generates a large amount of wood waste. The most relevant results obtained in this research show that the community generates approximately 2268 kg of sawdust and 5418 kg of shavings per week, and the estimated energy potential per year for both sawdust is 1.94 PJ and for shaving is 4.65 PJ. Based on the particle size observed, the wood residue can be used to generate pellets or briquettes. Other average results in sawdust and (shavings) are the following: initial moisture content 15.3% (16.8%), apparent density 169.23 kg/m3 (49.25 kg/m3), ash 0.43% (0.42%), volatile material 84.9% (83.60%), fixed carbon 14.65% (15.96%), hemicelluloses 12.89% (10.68%), cellulose 52.68% (52.82%), lignin 26.73% (25.98%), extractives 7.69% (10.51%), calorific value 17.6 MJ/kg (17.9 MJ/kg). The major chemical elements in the ash were Al, K. Fe, Ca, P, Na, and Mg. Finally, the results obtained indicate that this biomass can be used to generate pellets or briquettes in this indigenous community.

The objective of this research is to experimentally evaluate the anaerobic co-digestion of slaughterhouse residues in the city of Guaranda with straw residues from agriculture, such as: amaranth, quinoa and wheat. The study was carried out on a laboratory scale using 311 ml biodigesters under mesophilic conditions of 37 °C. Anaerobic co-digestion resulted in methane yields of 407 ml CH4/g VS, with a methane content in the biogas of 77% for the mixture of slaughterhouse waste and quinoa (RM-QU (25:75)). The increase in inoculum in the mixtures composed of slaughterhouse residues and quinoa increased the biodegradability between 17 and 22%. However, in the mixtures of slaughterhouse waste and amaranth (RM-AM (0:100)), a further increase in inoculum decreased biodegradability by 5%. To predict and simulate methane production, 5 kinetic models were used: modified Gompertz, logistic equation, transfer, cone and Richards. The cone model was the one that best adjusted the experimental values ​​with those predicted with an R2 of 0.982 to 0.999 and RMSE of 0.61 to 6.92 ml CH4/g VS. The calculation of the theoretical yield was carried out by stoichiometry and elemental analysis of the samples. Theoretical yields ranged between 480-564 ml CH4/g VS for all mixtures of RM with agricultural residues.

Pruning agroforestry areas generates significant amounts of lignocellulosic biomass every year. The energy production potential of this biomass is unclear. The aim of this research was to quantify the amount of pruning residues generated from Teak (Tectona grandis), which are composed by mixtures of wood and leaves. An equation from a regression model has been proposed to quantify these residues with a adjusted coefficient of determination (r2) of 0.73. On the other hand, mixtures with different wood/leaf ratios of Teak were characterized by its higher heating value (HHV), elemental composition, structural and proximate analysis. This analysis allowed for further development of indirect HHV prediction models that are economically attractive and less time consuming than direct measurements. These models presented high coefficients of determination (r2 0.66–0.77). It has been determined that teak has the highest mean HHV of 17,373.7 kJ kg−1 dry. Elemental analysis showed the highest carbon content was about 46.2%. Mean hydrogen content was 7.5%. Leaf content has influenced on ash and nitrogen percentages. Nevertheless, the amount of nitrogen did not reach 1% for mixtures with leaf ratio lower than 50%. It is concluded that the proposed model can be used to predict the biomass of teak pruning grown in Aw climatic conditions. From the characterization of these pruned materials, the energy, residues and emissions can be estimated.

[EN] A dendrometric and energetic characterisation of Tamarix africana L. was carried out in this study. This is an indigenous plant species in the Mediterranean area, and it can survive in semi-arid areas with saline soils and occasional floods. Owing to these characteristics, this species is a good candidate for its use in the restoration of several environments, such as the marshes. This opens up the possibility of improving the management of biomass, which can be used for obtaining economic benefits from its energetic use. For the stems, biomass volume functions were determined from their diameter and length with r(2) of 0.96. For the whole plant, biomass volume functions were determined from the diameter of the projected area in the soil and the height of the plant with r(2) of 0.95. For energetic characterisation, the density, higher heat value, and the composition of this wood were measured in terms of following elements: carbon, nitrogen, hydrogen, sulphur and chlorine, volatiles and ash. The determination of its composition in C allows us to evaluate the CO2 fixed by the plant during its growth. The average catchment was estimated to be 2.58 kg/plant., This work was financed by Project 20170734 entitled as follows: Development of methods of quantification of riparian vegetation bio-mass for the management of channels of the Comunidad Valenciana. Direccion General de Universidades. Generalitat Valenciana (Spain).

[ES] En este trabajo se presenta la experiencia de la aplicación de una metodología de enseñanza-aprendizaje basada en prácticas en asignaturas de temática agrícola y agroindustrial. Ésta consistió en dedicar un 70% de las horas a prácticas de campo y laboratorio, y un 30% de contenidos teóricos. Los contenidos teóricos fueron dirigidos a lecturas de bibliografía que después se exponen en foros antes de la aplicación de la práctica. Las prácticas se centraron en experimentar procesos propios de cada cultivo, tales como diferenciación de especies, técnicas de siembra y plantación, reconocimiento de plagas y enfermedades, técnicas de poda, realización de injertos etc. En las asignaturas de agroindustria, tales como aprovechamiento energético de la biomasa, las practicas se orientaron a ejercicios de laboratorio para calcular propiedades de materiales biocombustibles, tales como el poder calorífico, composición de CHN, cenizas etc. La evaluación se realiza de forma tradicional, mediante exámenes parciales y final. También se evalúan las memorias de prácticas. Los resultados obtenidos durante dos años mostraron un aumento de la puntuación de la valoración de la asignatura en las encuestas institucionales. El nivel de aprobados por curso aumentó alrededor de un 10%. Además se realizaron entrevistas para indagar en los aspectos relevantes de la técnica, realizando los alumnos análisis DAFO (Debilidades, Amenazas, Fortalezas, Oportunidades). Entre las debilidades más relevantes se muestra la exigencia de ir a clase para seguir bien el método diseñado de aprendizaje.

This paper evaluates the anaerobic digestion of agricultural waste, manure and slaughterhouse residues of species typical of the Andes, such as llama, vicuna and guinea pig; quinoa, amaranth and wheat straw in order to be able to use them as a renewable energy source and boost rural development in the region. Has been used sludge from a WWTP as inoculum, evaluating the effect of two relationships between the substrate and inoculum (RSI) for both livestock and agricultural waste. The highest cumulative maximum methane production rate was obtained for the residues of flame manure and quinoa straw for an RSI of 1:2 with productions of 376.08 ml CH4/g SV and 377.02 ml CH4/g SV respectively. In these materials an RSI of 1:2 obtained increases of 22.56% and 37.54% compared to the RSI 1:1. Also, the kinetic analysis showed that the modified Gompertz model is the one that best fits performance, with constant differences of 7.06% between the experimental and predicted values. On the other hand, the modified Gompertz model was adjusted to the experimental results with an r2 of (0.998) and an RMSE of 4.09 ml/g SV at 17.12 ml/g SV.

Objetivo. Determinar la respuesta de los indicadores productivos al incluir palmiste (Elaeis guineensis) en dietas para la nutrición de alevines de tilapia (Oreochromis niloticus). Material y métodos. Se utilizaron 300 machos masculinizados de tilapia (4,89 ± 0,09 g) y se distribuyeron bajo un diseño completamente al azar con tres repeticiones por tratamiento (20 peces por repetición). Se utilizó palmiste para formular cinco dietas isoproteicas (30,64%), isolipídicas (7,38%) e isoenergéticas (11,84 MJ kg-1 de alimento), control (T0), 5% (T5); 10% (T10); 15% (T15) y 20% (T20) para alimentar durante 60 días. Resultados. Los peces alimentados con los tratamientos T0, T5 y T10, no mostraron diferencias significativas (p> 0.05), pero sí con T15 y T20 en la digestibilidad de los nutrientes, el crecimiento y la composición del cuerpo. La inclusión de palmiste hasta el 20% de la dieta, disminuyó el costo del alimento. Se observó un alto grado de dependencia entre el contenido de fibra detergente neutro (%), la digestibilidad aparente de la materia seca (%) y la digestibilidad aparente de la proteína (%) (R2 = 0,732 y R2 = 0,774; p

The unique perspective that microalgae biomass presents for bioenergy production is currently being strongly considered. This type of biomass production involves large amounts of nutrients, due to nitrogen and phosphorous fertilizers, which impose production limitations. A viable alternative to fertilizers is wastewater, rich in essential nutrients (carbon, nitrogen, phosphorus, potassium). Therefore, Arthrospira platensis was cultivated in 150 mL photobioreactors with 70% (v/v) with the wastewater from a dairy industry, under a regime of light:dark cycles (12 h:12 h), with an irradiance of 140 &mu, mol m&minus, 2 s&minus, 1 photon. The discontinuous cultures were inoculated with an average concentration of chlorophyll-a of 13.19 &plusmn, 0.19 mg L&minus, 1. High biomass productivity was achieved in the cultures with wastewater from the dairy industry (1.1 &plusmn, 0.02 g L&minus, 1 d&minus, 1). This biomass was subjected to thermal and physical treatments, to be used in co-digestion with cattle manure. Co-digestion was carried out in a mesophilic regime (35 &deg, C) with a C: N ratio of 19:1, reaching a high methane yield of 482.54 &plusmn, 8.27 mL of CH4 g&minus, 1 volatile solids (VS), compared with control (cattle manure). The results demonstrate the effectiveness of the use of cyanobacterial biomass grown in wastewater to obtain bioenergy.

Three lactic acid strains were isolated from feces of the native Zungo Pelado breed of pigs (n = 5) and presumably identified as belonging to the Lactobacillaceae family by morphological techniques showing that they were Gram-positive/rod-shaped and catalase- and oxidase-negative. They were then identified by biochemical tests using API 50CHL as Lactobacillus plantarum (CAM6), Lactobacillus brevis (CAM7), and Lactobacillus acidophilus (CL4). However, 16S rRNA identification showed that all three strains were Lactobacillus plantarum. Additionally, all three isolates were able to grow in pH 3 and 4. Interestingly, the growth of the CAM7 strain decreased at pH 5.6 compared to that of the CAM6 strain (p &lt, 0.05), and the growth of the CL4 strain was reduced at pH 7(p &lt, 0.05). All three candidates showed good growth on bile salts (&ge, 0.15%), and CAM6 and CAM7 showed better tolerance at higher concentrations (0.30%). Similarly, all strains tolerated sodium chloride (NaCl) concentrations from 2 to 10%. These strains also grew well at all temperatures tested (30, 37, and 42 &deg, C). The CAM6 strain showed in vitro antibacterial activity against selected enteropathogenic bacteria (Escherichia coli strain NBRC 102203 and Salmonella enterica serovar Typhimurium 4.5.12) and commensal bacteria (Klebsiella pneumoniae ATCC BAA-1705D-5 and Pseudomonas aeruginosa ATCC 15442) and resistance to all antibiotics except amoxicillin. Further studies to evaluate the effects of these probiotic candidate strains in commercial pigs are currently underway.

[EN] Vasconcellea stipulata Badillo is a fruit tree native of the temperate areas of the Andes valleys, found between 2000 and 2600 m above sea level. The good organoleptic qualities and few seeds of its fruit, compared with those of other Caricas, give it a high potential in markets. The development of this crop would allow the economic development of small-scale farmers and contribute to the preservation of genetic resources native to the Andean region. However, there are few studies concerning its appropriate cultivation. The aim of this study was to analyze the effect of different pruning techniques under greenhouse conditions. Trees were pruned to one, two, or three axes, or not pruned (control). The experiment was performed in a tunnel greenhouse with polyethylene cover, located 2950 m above sea level in Querochaca (Ecuador),with an annual rainfall of 465mmand an average annual temperature of 12.9 8C. The duration of each stage of development was recorded. The number of flower clusters, number of flowers, production, incidence of diseases, and weight and size of fruit were recorded. Cuttings took over 90 days for getting before being transplanted into the greenhouse. Flowering began 283 days (40 weeks) after transplantation; fruit set began at 30 days after flowering (44 weeks after transplant); and the fruit started to mature 170 days after fruit set (69 weeks after transplant). The plants pruned to three axes had the greatest number of flowers and fruits and the greatest production, with an average 54 fruits per tree. Pruning had no effect on fruit dimensions., The participation of Borja Velazquez Marti in this work was possible by the funding from the Ecuadorian Government through PROMETEO program, leaded by the Secretaria Nacional de Educacion Superior, Ciencia y Tecnologia (SENESCYT).

The development of dendrometric methodologies could allow accurate estimation of variables associated with the crown, such as primary production (fruit and timber) and tree vigor. The aim of this work was to develop a suitable method to estimate woody biomass in plum trees (Prunus domestica L.) in Imbabura, Ecuador by using an adapted dendrometry. Form factors and regression models were defined for branch volume calculation. From this, the distribution of woody biomass in the crown tree was characterized in every stratum. Occupation Factor and regression models were obtained in order to calculate the biomass in the crown tree, which can be used to estimate the CO2 captured in its structure during its development. Regression models for calculation of whole volume of the tree and pruned biomass were directly obtained from crown diameter and crown height with Rajustated 2 of 0.74 and 0.81. The average moisture content of green material was 51%, and the average density of dry material was 0.66 ± 0.07 g cm−3. Proximate analysis of plum wood showed at 79.8 ± 9.2% volatiles and 2.1 ± 0.3% ash. Elemental analysis of the wood pointed to 46.5 ± 1.2% C, 6.1 ± 0.5% H, 46.3 ± 1.2% O, 0.6 ± 0.3% N, 0.06 ± 0.02% S and 0.02 ± 0.01% Cl. Cl, S and N contents are lower than the limits established by the standard EN 14691-part 4.With 46% of C, considering the relation 3.67 (44/12) between CO2 and C content, the CO2 sequestrated in the materials is 1.11 Mg m−3 wood material. Such method represents a tool to manage orchard resources and for assessing other parameters, such as raw materials for cultivation, fruit production, CO2 sink and waste materials (residual wood) used for energy or industry., The authors appreciate the financial support provided by the ECUMASA, Red ecuatoriana para la investigacion del aprovechamiento energetico de la biomasa.

The process of drying at the agroindustry level is considered the most important stage for the storage and conservation of food, but an inadequate sizing of the systems can generate an excessive consumption of fuel and energy. In the case of the agricultural sector, especially in small and medium producers in Ecuador, they tend to dry cereals outdoors, spreading the product over black plastics, asphalt floors, or cements called &ldquo, tendal&rdquo, This process depends on the weather conditions of the area and can take between one or four days of drying, tending to damage the product by fungi. On the other hand, certain producers build dryers empirically, using as the main fuel gas for domestic use, diesel, or firewood. Among the problems presented for these types of dryers are heat losses in the drying chamber as it is not thermally insolated, a lack of temperature control (above 60 &deg, C) and drying speed, excessive fuel use, and 10% burned product, which are essential to control to obtain a quality product and savings in the energy consumption of the dryer. With regard to the problem raised above, the design and construction of a hybrid dryer that worked with 80% of thermal solar and low enthalpy aerogeothermal energy and 20% with electric power was conducted to optimize the drying process and ensure a quality dry product. The work proposes the dimensioning of each component of the dryer. As a result, it was found that the efficiency of the equipment was around 60%, reaching a maximum operating temperature of 52 &deg, C, with a stabilization time of the system in the first hour within 40 min. It should be noted that the design of the prototype is easy to adapt and replicate.

Agricultural residues have gained increasing interest as a source of renewable energy. The development of methods and techniques that allow to inventory residual biomass needs to be explored further. In this study, the residual biomass of olive trees was estimated based on parameters derived from using a Terrestrial Laser Scanning System (TLS). To this end, 32 olive trees in 2 orchards in the municipality of Viver, Central Eastern Spain, were selected and measured using a TLS system. The residual biomass of these trees was pruned and weighed. Several algorithms were applied to the TLS data to compute the main parameters of the trees: total height, crown height, crown diameter and crown volume. Regarding the last parameter, 4 methods were tested: the global convex hull volume, the convex hull by slice volume, the section volume, and the volume measured by voxels. In addition, several statistics were computed from the crown points for each tree. Regression models were calculated to predict residual biomass using 3 sets of potential explicative variables: firstly, the height statistics retrieved from 3D cloud data for each crown tree, secondly, the parameters of the trees derived from TLS data and finally, the combination of both sets of variables. Strong relationships between residual biomass and TLS parameters (crown volume parameters) were found (R2 = 0.86, RMSE = 2.78 kg). The pruning biomass prediction fraction was improved by 6%, in terms of R2, when the variance of the crown-point elevations was selected (R2 = 0.92, RMSE = 2.01 kg). The study offers some important insights into the quantification of residual biomass, which is essential information for the production of biofuel.

In this work, a new approach to evaluating the amount of residual biomass obtained from orange trees based on normalization of variables is proposed for Bolivar province, Ecuador. So far, several models to quantify the amount of residues obtained from pruning have been proposed from dendrometric and cultivation variables, such as height, crown diameter, stem diameter, area per plant, yield, and age. However, the high dispersion of their values, caused by uncontrolled conditions, gave models with a low-medium coefficient of determination. The aim of this work has been to develop several models in order to predict wet available biomass using dimensionless dendrometric parameters from height, diameter and height of the crown, and the stem height. They improved the coefficients of determination to 0.94 for the global mathematical model. The drying process of pruned materials has also been analyzed. Residual biomass with 50% initial moisture content was dried outdoors on cement and agricultural soil until it reached constant moisture content. Models used to describe the drying process of agricultural products were employed to fit the observed data of the drying process of orange tree chips. Among the tested models, the Midili and Page models were those that best fitted the observed data in the drying process. The information offered by these equations is of vital importance because they help estimate the amount of biomass that is generated in a given area, and the implementation geographic information system (GIS) maps. In addition, logistic algorithms can be applied. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

[EN] The use of biomass raw material from agricultural areas is a challenge for Ecuatorian government. However there is lack information about surveying systems and processing in its height and weather conditions. The objective of this work was to develop methods to quantify straw residues, easily applicable in corn areas of Guaranda (Ecuador), and model the drying process at different air conditions. Two dendrometric equations were obtained for predicting dry available biomass by stem and cultivated area respectively, from corn mean height and radius of the stem. High coefficients of determination were obtained (0.94 and 0.97 respectively). Straw chips with initial moisture content ranging from 70 to 80% with an average moisture content of 76.7% wet basis were dried until they reached constant moisture content. Traditional models used to describe the drying process of agricultural products were employed to fit the observed data of the drying process of straw corn chips. Among the tested models, the Midili, Page, and sigmoid model were those that best fit the observed data representing the drying process. The effective diffusion (Def) was determined by means of an analytical solution of Fick's second law. Effective moisture diffusivity values obtained at natural outdoor drying conditions were 2.443E-11 and 2.035E-10 m2/s, for the first and second falling periods, respectively., The participation of Dr. Sergio Perez and Dr. Zulay Nino-Ruiz in this work was possible by funding from the Ecuadorian Government by means of PROMETEO program, leaded by the Secretaria Nacional de Educacion Superior, Ciencia y Tecnologia (SENESCYT).

A review of the chemical composition of the Moringa oleifera forage meal (leaves plus stems) and the possibilities of safe use in the feeding of non-ruminant animals was made. The forage meal obtained from Moringa oleifera at 35 to 60 days from regrowth and cut at 5 to 40 cm height from the soil has good protein concentration, and its amino acid content is similar to the alfalfa forage meal. In addition, the moringa forage meal has a high content of crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL), which must cause a low content of metabolizable energy (ME) for poultry and pigs. Apparently, the contribution of secondary metabolites and bioactive substances at low concentrations does not harm the growth performance and quality of the final product. Moreover, we recommend favorable levels of inclusion in the diets of poultry, pigs and rabbits.

[EN] For the economically depressed communities such as of those in the Canton Guaranda, Ecuador, to generate their own energy, from organic waste is very important because they are sometimes insulated and its gas and electricity supply is very deficient. The aim of this research, was to determine the feasibility of anaerobic co-digestion of wasted cabbage from the town's market in Guaranda, Ecuador, and livestock manure. Two variables were studied: temperature of the process and the percentage of cabbage and livestock manure. Biogas quantity and kinetic parameters were evaluated. Kinetic model were analyzed by minimizing the mean percentage of error between the observed values (measured experimentally) and predicted, using the Runge-Kutta of order 4 for solving the system of differential equations obtained from mass balance. The results showed that a 50-50% ratio cabbage-manure at 30 degrees C temperature gave the highest production of biogas achieved is (389.47cm(3)N/g initial SV) with a composition of 61% methane. The kinetic parameters found were mu(max)=0.1053day(-1); Ks=0.1153mg/l; Y=0.00246g VSS /g COD and K-dec=0.001005day(-1)., This research work has been carried out inside the cooperation framework funded by the ADSIDEO program of the Centro de Cooperacion al Desarrollo (CCD) of Universidad Politecnica de Valencia (Spain), in collaboration with the Centro de Estudios de la Biomasa (CEB), Universidad Estatal de Bolivar, Guaranda, Ecuador. The participation of Dr. Sergio Perez in this work was possible thanks to funding from the Ecuadorian Government by means of the PROMETEO program, led by the Secretaria Nacional de Educacion Superior, Ciencia y Tecnologia (SENESCYT).

[EN] The objective of this work was to perform a complete evaluation of using biomass from pruning residues of ficus trees (Ficus benjamina), widely grown as ornamental plants in cities in Ecuador. Due to their great capacity for propagation and fast growth, these trees need frequent pruning and so generate a large amount of ligneous residues. A dendrometric analysis of the plant was performed to calculate the quantity of residues generated from easily measurable variables, such as crown diameter and plant height. The models obtained gave a coefficient of determination of R2 = 0.75. Pruning residues included mixtures of wood and leaves. The percentages of leaf and woody biomass were measured and a calorific analysis, elemental analysis, proximal analysis and structural analysis of the different mix proportions were carried out. Nitrogen content was acceptable for use as biofuel. Ash content in the wood is 5%, but the inclusion of leaves in the sample increases the ash content up to 11% when the leaf percentage is greater than 50%. About 10 kg of material, on average, was obtained from each tree. The mean calorific value of these residues was 19 MJ kg¿1 and was influenced by the volatile content and lignin., This work has been funded by Universidad Catolica Santiago de Guayaquil through a research program coordinated by the Sistema de Investigacion y Desarrollo (SINDE).

[EN] This study compares the estimations of biophysical parameters of Platanus hispanica urban trees, namely total height, crown height, crown volume, and the amount of residual biomass from pruning, obtained by terrestrial laser scanner (TLS), airborne laser scanner (ALS)of low density (0.7 points · m¿2), and measured by standard field methods. Regression models were calculated to obtain the relationships among parameters retrieved by all techniques, testing all possible combinations (manual-TLS, manual-ALS, TLS-ALS, and vice versa). The most accurate fits were found for vegetation attributes (stem and crown diameter) estimated by TLS and ALS data with R2 between 0.84 and 0.96, respectively. The least accurate models were found when crown height and pruning biomass were estimated from ALS data (R2 ¿ 0.68 and R2 ¿ 0.59, respectively). The methods reported in this research might be of interest for the management of urban forests to study residual biomass calculation, sink CO2, the influence of humidity and of shadow areas whatever the information capture system used, whether it is derived from ALS, TLS, or classical dendrometry measurements.

La aplicación de modelos de teoría de colas es una de las herramientas estadísticas para la optimización de los servicios hospitalarios. En este artículo se muestran los procedimientos de cálculo y las variables que deben registrarse. El análisis del sistema ha comenzado por la determinación de la distribución de los tiempos de llegadas de los pacientes, junto a la duración y los tiempos de la atención. Para el análisis se propuso realizar una segmentación del día que permitió considerar la hipótesis de que las distribuciones de los tiempos de llegada y tiempos de atención eran uniformes en cada segmento horario. El modelo propuesto ha pretendido analizar cada segmento para reducir tiempos de espera en centros de emergencia hospitalaria, mediante la abertura de servicios de emergencia, en centros de salud de atención primaria, orientados a enfermedades de menor gravedad que no precisan hospitalización. De esta manera los servicios de emergencia hospitalarios estarán menos saturados. El modelo ha permitido calcular el número óptimo de servicios de emergencias en centros de salud primaria para que no exista riesgo alguno de desestabilización del sistema de emergencia hospitalario.

The amount of residual biomass from pruning operations of urban trees is a potentially abundant, and an underutilized source that could contribute significantly more to regional and national bio-economies than it does at present. Better utilization of woody biomass from urban green space, leisure and industrial areas could offer bio-based fuels for heat and power generation, reduce pressure on forests and reduce the management costs on a local and regional level. The aim of the work was to quantify woody biomass proceeding from pruning operations and verify the potential of using allometric relationships developed for urban forests. Quantitative results of the residual wood biomass obtained from annual pruning operations of Sophora japonica are presented in the paper according to the type of pruning practice applied. Wood formed 59.97% of total weight of all pruned material before the drying process, wood moisture content in wet basis was 44.88% and mean quantity of dry biomass (branches without leaves) obtained per tree was 18.07 kg. Regression models were applied to predict weight of dry biomass obtained per tree. Significant relationship was observed between quantity of biomass and diameter at breast height at R2 = 0.60. The analysis indicates that an abundant amount of residual biomass originating from pruning operations of ornamental species can be used to achieve ecological and energy targets. Moreover, the presented methodology creates a tool for better prediction of income, field work and logistics management for the future.

Several studies have addressed the biomass and volume of trees using Airborne Light Detection and Ranging (LiDAR) data. However, little research has been conducted into shrub vegetation, which covers a high percentage of Mediterranean forest. We used LiDAR data and an airborne image to estimate biomass and volume of shrub vegetation. Field data were collected in 29 square plots of 100 m2. In each plot, the percentage of the surface covered was measured in the field. Shrub vegetation inside 3 stands for each plot was clear cut to calculate the biomass and volume of the 29 plots. To find the best fit between LiDARspectral data and field measurements, stepwise regressions were performed using previously selected variables. The highest accuracy was found when variables derived from LiDAR data and the airborne image were combined (R2 values of 0.78 and 0.84 for biomass and volume, respectively). Biomass and volume were predicted using variables from height metrics of LiDAR data (median and standard deviation); density metrics (percentage of points whose height was between 0.50 m and 0.75 m, 0.75 me1 m, and higher than 1 m); and spectral data (standard deviation of green band, mean of the vegetation index NDVI). These results revealed the potential of LiDAR and spectral data to characterize shrub structure and make it possible to estimate and map the biomass and volume of this vegetation.

The creation of a quality Digital Terrain Model (DTM) is essential for representing and analyzing the Earth in a digital form. The continuous improvements in the acquisition and the potential of airborne Light Detection and Ranging (LiDAR) data are increasing the range of applications of this technique to the study of the Earth surface. The aim of this study was to determine the optimal parameters for calculating a DTM by using an iterative algorithm to select minimum elevations from LiDAR data in a steep mountain area with shrub vegetation. The parameters were: input data type, analysis window size, and height thresholds. The effects of slope, point density, and vegetation on DTM accuracy were also analyzed. The results showed that the lowest root mean square error (RMSE) was obtained with an analysis window size of 10 m, 5 m, and 2.5 m, rasterized data as input data, and height thresholds equal to or greater than 1.5 m. These parameters showed a RMSE of 0.19 m. When terrain slope varied from 0–10% to 50...

This research quantified the available residual biomass obtained from pruning vines stock. The additional biomass quantified could be used as a source of energy or as raw material for the wood industry and would provide additional income for fruit producers and also a more sustainable system. Several factors were analyzed: Variety, aim of the pruning, age of the plants, size of the plantation, crop yield and irrigation. Regression models were also calculated to predict the weight of dry biomass, obtained per tree and tonnes of dry biomass obtained per hectare, according to the significant factors. These equations could implement logistic planning as the Borvemar model, which defines a logistics network for supplying bio-energy systems. The results show that the shape of the structure of plantation has a strong influence on the quantity of biomass produced, and therefore on the quantity of pruning material. In the vineyards cultivated for fresh grape production, the horizontal trellis produces 3.5 kg/tree and 4.2 t/ha, the more dry matter per vine tree than the double of the high trellis, and the triple than the standard trellis. In the vineyards cultivated for wine production, the standard trellis and vase shape do not have significant differences, reaching 0.8 kg dry matter per vine tree. Nevertheless, on the other hand, the standard trellis produces 2.15 t/ha, a 25% more dry biomass per hectare than the vase shape. The presence of irrigation increases biomass in vineyards by 42%. © 2011 Elsevier Ltd.

This work uses the Labour Economics and Sociology Laboratory of France (LEST) method to evaluate the ergonomic-psycholsociological quality of work in horticultural greenhouse exploitations in Almeria (Spain) with the aim of improving workers’ occupational health. Data on the factors affecting the physical environment, the physical workload, mental workload, psychosocial aspects and the working hours of labourers were collected in 110 greenhouses, 35 of the Almeria parral - plano type and 75 of the raspa y amagado type. The crops raised in these greenhouses were cucumbers (24 greenhouses), peppers (25), aubergines (28), and melons (38). These greenhouses, typical of southeastern Spain, were found not to guarantee workers a comfortable working environment. The type of greenhouse and the crop raised within directly affected the ergonomic-psychosocial conditions of the workers. Suggestions are offered that might improve these conditions.

[EN] This research quantified the available residual biomass obtained from pruning almond trees. The additional biomass quantified could be used as a source of energy or as raw material for the wood industry and would provide additional income for fruit producers and also a more sustainable system. Several factors were analyzed: Variety, aim of the pruning, age of the plants, size of the plantation, crop yield and irrigation. Regression models were also calculated to predict the weight of dry biomass obtained per tree and tonnes of dry biomass obtained per hectare according to the significant factors. These equations could implement logistic planning as the Borvemar model, which defines a logistics network for supplying bioenergy systems. Almond tree varieties were classified into three groups: a first group with high residual biomass productivity (average yield 12.6. kg dry biomass/tree), a second group with low productivity (average yield 4.5. kg dry biomass/tree) and a transition group with a intermediate biomass yield of 7. kg dry biomass/tree. This means that in Mediterranean areas the residual biomass from almond pruning reaches an average 1.34. t/ha annual. © 2010 Elsevier Ltd.