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Hydrolytic activity was evaluated in a mixture of supernatants produced by filamentous fungi grown individually on microcrystalline cellulose and empty fruit bunches. The strains that were used correspond to two types of isolates; the first was made from soil samples from a transect of a high andean forest of Colombia, in the Parque Natural Nacional de Los Nevados, where, based on previous studies, we selected the strains B7, B11, B11M and B19. The second isolate was obtained from a pool of oil palm empty fruit bunches (Eleaeis guinensis Jacq.) in different states of decomposition on the Unipalma plantation located in the eastern plains; strains TA1 and TA2. To perform the hydrolysis of cellulose and empty fruit bunches, the previously obtained supernatants from each of the selected strains were cultivated for 300 hours in cellulose and characterized individually by endoglucanase, exoglucanase, and β-glucosidase activity. Individual supernatants were mixed at a 1:1 ratio to form consortia; and hydrolytic activity was evaluated in the substrates at two hours. The glucose concentration was determined by the 3,5-dinitrosalicylic acid (DNS) method. The results show that hydrolysis of empty fruit bunch to glucose was favored by three pools of supernatants, with increases greater than 400% in comparison with the hydrolysis obtained by individual supernatants, demonstrating the potential to decompose palm empty fruit bunches; thereby contributing to the reduction of decay time of empty fruit bunches and the decrease of environmental and health problems

Hydrolytic activity was evaluated in a mixture of supernatants produced by filamentous fungi grown individually on microcrystalline cellulose and empty fruit bunches. The strains that were used correspond to two types of isolates; the first was made from soil samples from a transect of a high andean forest of Colombia, in the Parque Natural Nacional de Los Nevados, where, based on previous studies, we selected the strains B7, B11, B11M and B19. The second isolate was obtained from a pool of oil palm empty fruit bunches (Eleaeis guinensis Jacq.) in different states of decomposition on the Unipalma plantation located in the eastern plains; strains TA1 and TA2. To perform the hydrolysis of cellulose and empty fruit bunches, the previously obtained supernatants from each of the selected strains were cultivated for 300 hours in cellulose and characterized individually by endoglucanase, exoglucanase, and β-glucosidase activity. Individual supernatants were mixed at a 1:1 ratio to form consortia; and hydrolytic activity was evaluated in the substrates at two hours. The glucose concentration was determined by the 3,5-dinitrosalicylic acid (DNS) method. The results show that hydrolysis of empty fruit bunch to glucose was favored by three pools of supernatants, with increases greater than 400% in comparison with the hydrolysis obtained by individual supernatants, demonstrating the potential to decompose palm empty fruit bunches; thereby contributing to the reduction of decay time of empty fruit bunches and the decrease of environmental and health problems

Este documento presenta la validación del producto global de área quemada L3JRC en Colombia utilizando el método de matrices de confusión e imágenes de satélite Landsat como sustituto a la verdad terreno. El producto L3JRC, generado por Tansey et al. en el año 2007, es un mapa de áreas quemadas obtenido por teledetección con datos del instrumento SPOT-VEGETATION. La determinación del área quemada generada por los incendios se obtiene por teledetección gracias a la diferencia en reflectividad antes del fuego (vegetación) y después del fuego. La validación del producto demuestra clara tendencia hacia la omisión de áreas quemadas, aunque también con errores importantes por comisión. Sin tener en cuenta el tipo de error, se encontró que el producto L3JRC subestima en 40% la superficie quemada del país. Con las consideraciones en la fiabilidad se concluye que el promedio anual de área quemada en Colombia es de 14.807 km² aunque podría superar los 21.000 km² si se tienen en cuenta los altos valores de omisión y subestimación detectados en la validación. La región de la Orinoquia tiene más del 90% del área total del país, siendo los departamentos colombianos con mayor área quemada Vichada, Meta, Arauca y Casanare.This document presents a validation of the global burned area product (L3JRC) in Colombia, using the method of the confusion matrix where Landsat images are used as a proxy for fieldwork. The product L3JRC is a burned area map based on remote sensing SPOT-VEGETATION data and generated by Tansey et al. in 2007. Determination of burned area using satellite data is possible because of the difference in reflectance before and after a fire. A pattern toward larger omission errors was found in the validation process, although commission errors also were present. Disregarding the type of error, it was shown that the product L3JRC underestimates 40% of the burned area of the country. With this accuracy of assessment, it was concluded that the annual average burned area in Colombia during the annual study period was 14,807 km², taking into account omission values burned area may exceed 21.000 km². Orinoquia region has more than (90%), of the total burned area of the country, where Vichada, Meta, Arauca, and Casanare were the most affected Colombian departments.

Este documento presenta la validación del producto global de área quemada L3JRC en Colombia utilizando el método de matrices de confusión e imágenes de satélite Landsat como sustituto a la verdad terreno. El producto L3JRC, generado por Tansey et al. en el año 2007, es un mapa de áreas quemadas obtenido por teledetección con datos del instrumento SPOT-VEGETATION. La determinación del área quemada generada por los incendios se obtiene por teledetección gracias a la diferencia en reflectividad antes del fuego (vegetación) y después del fuego. La validación del producto demuestra clara tendencia hacia la omisión de áreas quemadas, aunque también con errores importantes por comisión. Sin tener en cuenta el tipo de error, se encontró que el producto L3JRC subestima en 40% la superficie quemada del país. Con las consideraciones en la fiabilidad se concluye que el promedio anual de área quemada en Colombia es de 14.807 km² aunque podría superar los 21.000 km² si se tienen en cuenta los altos valores de omisión y subestimación detectados en la validación. La región de la Orinoquia tiene más del 90% del área total del país, siendo los departamentos colombianos con mayor área quemada Vichada, Meta, Arauca y Casanare.This document presents a validation of the global burned area product (L3JRC) in Colombia, using the method of the confusion matrix where Landsat images are used as a proxy for fieldwork. The product L3JRC is a burned area map based on remote sensing SPOT-VEGETATION data and generated by Tansey et al. in 2007. Determination of burned area using satellite data is possible because of the difference in reflectance before and after a fire. A pattern toward larger omission errors was found in the validation process, although commission errors also were present. Disregarding the type of error, it was shown that the product L3JRC underestimates 40% of the burned area of the country. With this accuracy of assessment, it was concluded that the annual average burned area in Colombia during the annual study period was 14,807 km², taking into account omission values burned area may exceed 21.000 km². Orinoquia region has more than (90%), of the total burned area of the country, where Vichada, Meta, Arauca, and Casanare were the most affected Colombian departments.

Batch trials were carried out to evaluate the Biochemical Methane Potential (BMP) of 61 different substrates collected from agricultural farms and industrial sites in Estonia. Tests were performed in 500 mL plasma bottles at 36°C. The highest methane yield from all tested substrates was obtained from unconsumed dairy products (557 ± 101 L kg-1 VS) while the lowest was obtained from animal slurries (238 L kg-1 VS ± 42). From tested energy crops, foxtail millet achieved the highest methane yield (320 L kg-1 VS). Silages from different crops presented methane yields from 296 ± 31 L CH4 kg-1 VS to 319 ± 19 L CH4 kg-1 VS. The influence of chemical composition and kinetic rate constants (k) on methane potential was analyzed. Anaerobic digestibility of selected agro-industrial substrates was markedly influenced by their organic content, i.e. total proteins and lignin concentrations. Rate constants were found to correlate negatively with hemicellulose, cellulose and lignin (p < 0.05). Results from this study suggest that an appropriate characterization of the chemical composition of the substrates is important not only for predicting BMP and the kinetics rates, but also for identifying possible inhibitors during the anaerobic digestion process. Results on the BMP and national availability of studied substrates indicate that herbal biomass and agro-industrial residues are promising substrates for biogas production in agricultural biogas facilities in Estonia.

Batch trials were carried out to evaluate the Biochemical Methane Potential (BMP) of 61 different substrates collected from agricultural farms and industrial sites in Estonia. Tests were performed in 500 mL plasma bottles at 36°C. The highest methane yield from all tested substrates was obtained from unconsumed dairy products (557 ± 101 L kg-1 VS) while the lowest was obtained from animal slurries (238 L kg-1 VS ± 42). From tested energy crops, foxtail millet achieved the highest methane yield (320 L kg-1 VS). Silages from different crops presented methane yields from 296 ± 31 L CH4 kg-1 VS to 319 ± 19 L CH4 kg-1 VS. The influence of chemical composition and kinetic rate constants (k) on methane potential was analyzed. Anaerobic digestibility of selected agro-industrial substrates was markedly influenced by their organic content, i.e. total proteins and lignin concentrations. Rate constants were found to correlate negatively with hemicellulose, cellulose and lignin (p < 0.05). Results from this study suggest that an appropriate characterization of the chemical composition of the substrates is important not only for predicting BMP and the kinetics rates, but also for identifying possible inhibitors during the anaerobic digestion process. Results on the BMP and national availability of studied substrates indicate that herbal biomass and agro-industrial residues are promising substrates for biogas production in agricultural biogas facilities in Estonia.

Existen dificultades para determinar el peso de los macroinvertebrados y conocer así su importancia energética dentro de un ecosistema acuático. Por lo tanto, el objetivo de este estudio fue hallar relaciones matemáticas entre la longitud y la biomasa en dos géneros de invertebrados, representativos en el humedal Jaboque (Engativá) Bogotá D. C., Colombia, que faciliten hallar el peso de los individuos. Para ello, se realizaron cuatro muestreos desde abril de 2009 a enero de 2010. Se obtuvieron ecuaciones para estimar el peso seco a partir de medidas de la longitud total del cuerpo, para los géneros Helobdella y Asellus. Las relaciones halladas entre longitud total y peso seco fueron significativas y explicaron al menos el 69% de la varianza, expresada en los coeficientes de correlación (r² = 0,69 y 0,85). Estos modelos permitirán calcular la biomasa para determinar el crecimiento y la producción secundaria de estos taxones en posteriores estudios de laboratorio o de campo. También podrían ayudar a conocer la importancia de estos organismos en el flujo de energía en los ecosistemas acuáticos, principalmente en los humedales andinos urbanos, donde son muy abundantes.

Existen dificultades para determinar el peso de los macroinvertebrados y conocer así su importancia energética dentro de un ecosistema acuático. Por lo tanto, el objetivo de este estudio fue hallar relaciones matemáticas entre la longitud y la biomasa en dos géneros de invertebrados, representativos en el humedal Jaboque (Engativá) Bogotá D. C., Colombia, que faciliten hallar el peso de los individuos. Para ello, se realizaron cuatro muestreos desde abril de 2009 a enero de 2010. Se obtuvieron ecuaciones para estimar el peso seco a partir de medidas de la longitud total del cuerpo, para los géneros Helobdella y Asellus. Las relaciones halladas entre longitud total y peso seco fueron significativas y explicaron al menos el 69% de la varianza, expresada en los coeficientes de correlación (r² = 0,69 y 0,85). Estos modelos permitirán calcular la biomasa para determinar el crecimiento y la producción secundaria de estos taxones en posteriores estudios de laboratorio o de campo. También podrían ayudar a conocer la importancia de estos organismos en el flujo de energía en los ecosistemas acuáticos, principalmente en los humedales andinos urbanos, donde son muy abundantes.

Objetivo. Describir la respuesta endocrina asociada con la reproducción de un pez potamódromo tropical ante cambios en el régimen de descarga de caudal producido por la generación de hidro-energía en un río Andino. Materiales y métodos. Se analizó la reproducción de Prochilodus magdalenae en individuos de dos sectores de una cuenca neotropical: uno con flujo hidrológico natural y otro con un régimen regulado. Resultados. En la sección de la cuenca con flujo natural, se encontró que la producción de hormonas relacionadas con la reproducción de peces (FSH y LH) estaba correlacionada con el índice gonadosomático, mientras que en peces bajo la influencia del pulso de agua producto de la operación hidroeléctrica esta correlación no fue detectada. Conclusiones. La producción de hormonas asociadas con la reproducción en peces potamódromos fue sensible a cambios en el nivel/caudal. En consecuencia, peces expuestos a las alteraciones en el pulso de caudal estarían recibiendo estímulos ambiguos que afectan la producción de hormonas, la sincronización de la reproducción con las señales ambientales y la maduración, lo cual es esencial para el éxito reproductivo. Objective. Describe the endocrine response associated with the reproduction of a tropical potamodromous fish under changes in the flow discharge produced by hydropower in an Andean. Materials and methods. We analyzed Prochilodus magdalenae reproduction in individuals from two sectors of a Neotropical river basin: one with the natural flow and the other with a regulated hydrological regime. Results. In the sector of the basin with the natural flow we found that the production of hormones related with fish reproduction (FSH and LH) was correlated with the gonadosomatic index, while in fish experiencing hydropeaking due to hydroelectric operation no such correlation was detected. Conclusions. Hormone production associated to reproduction of the Potamodromous fish was sensitive to changes in water level and discharge. Then, fish exposed to hydropeaking would be receiving ambiguous stimuli that affect hormone production, reproduction synchronization with environmental cues, and ripening, which are essential for reproductive success.