Optimizing the Reduction of Total Suspended Solids in Pump Water from Fish Factories Through Electrocoagulation using Response Surface Methodology

This study aims to optimize the removal of total suspended solids (TSS) in pump water from fish flour factories through electrocoagulation technology and to determine the effects of the main operation parameters. Pump water has high conductivity (40.1 mS), due to the presence of dissolved salts and contains high concentration of organic substances (12,360 mg/L of TSS and 520 mg/L of fats). In this study, pump water was treated in an electrocoagulation reactor with aluminum electrodes using Response Surface Methodology with a 3kfactorial design based on two factors, current intensity (I) of 8–13 A and treatment time (t) of 20–40 minutes. The percentage of TSS removed from the water was used as the response variable. The results revealed that I and t significantly (p < 0.05) influenced the process. In accordance, the optimal operational parameters for TSS removal were I = 13 A and t = 30 minutes. Using these conditions, TSS removal efficiency of 99.9% was achieved. The sewage sludge generated with these optimal process conditions indicated 19.3% of ash content, 6.2% of salt, 1.7% of aluminum, 0.3% of iron, 0.4% of potassium, 256 ppm of zinc, and 2.1% of phosphorus. Hence, the results of this study affirm that electrocoagulation can be considered as a solution for marine pollution caused by fishing industries

Variabilidad temporal en la estructura y composición de la macrofauna bentónica en playa Atenas, Pisco

En este estudio se analiza la variación temporal y espacial de la abundancia, biomasa, diversidad y estructura comunitaria de la epifauna macrobentónica de Playa Atenas, localizada en la Bahía de Paracas; así como su relación con algunos factores abióticos. Para ello, mensualmente se colectaron muestras de bentos mediante buceo semiautónomo a 0, 3 y 5 m de profundidad durante septiembre del 2004 a agosto 2005. Se registraron 52 especies, siendo los grupos taxonómicos con mayor número de especies los crustáceos (36.5 %) y los moluscos (32.7 %). Los cirrípedos presentaron los valores más altos de densidad (60.3 ind/m2), mientras que las especies, Argopecten purpuratus y Crepipatella dilatata presentaron los valores más altos en biomasa (34.6 y 20.6 g/m2 respectivamente). Tanto la densidad como la biomasa promedio, se incrementaron de primavera a invierno, siendo este significativo en las estaciones de orilla y a tres metros de profundidad. De primavera a invierno, la diversidad decreció mientras que la dominancia aumentó significativamente, manteniéndose la equidad constante. Se observó en general, un patrón de disminución de la riqueza y el número de especies con el incremento de la profundidad, aunque con una mayor diversidad y equidad. En cuanto al análisis de similaridad, las estaciones de 3 y 5 m de profundidad tendieron a agruparse, mientras que la de orilla, a aislarse. La asociación entre especies se dio principalmente por el tipo de sustrato, asociado en cierta medida a la densidad de valvas de Argopecten purpuratus. La temperatura y el oxígeno disuelto se correlacionaron significativamente de forma negativa con la biomasa, mientras que los nutrientes se correlacionaron positivamente con la mayoría de los índices comunitarios. Con la información obtenida en este estudio, así como información publicada sobre hábitos alimenticios, se construyó un modelo conceptual de la estructura trófica de Playa Atenas. Se identificaron 20 grupos funcionales en tres niveles tróficos, siendo los depredadores tope, Octopus mimus, cangrejos predadores y gastrópodos predadores. Se discute la presencia o incremento de algunas especies, vientos y corrientes, como los principales factores de variabilidad temporal en densidad, biomasa y diversidad. De la misma manera, se discute la presencia y densidad de valvas de Argopecten purpuratus, como un factor importante en la variación batimétrica, tanto de la distribución y abundancia de las especies, como de los índices comunitarios.In this study, the temporal and spatial variation in abundance, biomass, diversity and community structure of macro benthic epifauna of Playa Atenas, located at Paracas Bay, is analyzed; and also, their relationship with some abiotic factors. For this, benthic samples were collected monthly, by semi-autonomous diving at 0, 3 and 5 meter depths, during september 2004 to august 2005. Fifty two species were recorded, being crustaceans (36.5%) and molluscs (32.7%), the taxa with more species. Barnacles had the highest density values (60.3 ind/m2), while the species, Argopecten purpuratus and Crepipatella dilatata, showed the highest biomass values (34.6 and 20.6 g/m2 respectively). Both, average density and biomass increased from spring to winter, being this significant at shore stations and three meters depth. From spring to winter, diversity decreased while dominance increased significantly, remaining equity constant. It was generally observed, a decrease pattern in richness and number of species with increasing depth, but with a greater diversity and equity. As for the similarity analysis, stations at three and five meters depth, tended to cluster, while the stations located on the shore, to isolate. The association between species was mainly due to the type of substrate, associated somewhat, to the density of Argopecten purpuratus shells. Temperature and dissolved oxygen were negatively correlated with biomass in a significant way, while nutrients were positively correlated with most of the community indices. With the information obtained in this study as well as published information on eating habits, a conceptual model of the trophic structure of Playa Atenas was built. Twenty functional groups were identified on three trophic levels, being the top predators, Octopus mimus, predator crabs and predator gastropods. It is discussed the presence or increase in some species, winds and currents, as the main factors of temporal variability in density, biomass and diversity. In the same way, the presence and density of Argopecten purpuratus shells, is discussed as an important factor in bathymetric variation, of both the distribution and abundance of species, as community indices.TesisUniversidad Nacional Agraria La Molina. Facultad de Pesquería. Departamento Académico de Manejo Pesquero y Medio Ambient

Sustitución del tratamiento convencional del agua de bombeo de pescado mediante la adaptación de la tecnología de electrocoagulación para alcanzar los LMP a más bajo costo

El agua de bombeo que se genera al trasladar el pescado de las embarcaciones a las plantas de procesamiento de harina de pescado contiene una alta proporción de sólidos suspendidos y grasas. Alcanzar los límites máximos permisibles (LMP) exige que se le trate con agentes químicos y otros polímeros sintéticos. Estos, además de impactar negativamente en los costos, propician la recuperación de sólidos de mala calidad, con alto contenido de metales y de bajo valor. El objetivo del estudio es adaptar la tecnología de ectrocoagulación para aplicarla en el tratamiento de agua de bombeo de pescado y alcanzar los LMP a más bajo costo, prescindiendo del uso de químicos y favoreciendo la recuperación de sólidos de mejor calidad para ser utilizados en aplicaciones alimentarias y agrícolas de mayor valor

A Coffee Berry Borer (Coleoptera: Curculionidae: Scolytinae) Bibliography

Native to Africa, the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), has gradually invaded most coffee-growing areas worldwide. Adult females colonize the coffee berry and oviposit within galleries in the coffee seeds. Larvae and adults consume the seeds, resulting in drastic reductions in yields and quality, negatively affecting the income of approximately 20 million coffee-growing families (~100 million people) in ~80 countries, with losses surpassing more than $500 million annually (Vega et al. 2015). It has become evident that the coffee berry borer scientific community could greatly benefit from having access to a bibliography of the literature related to the insect. Such an information source would allow scientists to find out what research areas have been explored throughout the many coffee berry borer-infested countries after more than 100 years of research on the topic. It could also help to direct lead future research efforts into novel areas, and away from topics and ideas that have been thoroughly investigated in the past