Repositorio Digital Ikiam (Univ. Regional Amazónica)
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Support method for interpretation of regional groundwater monitoring in urban areas
Get PDFUrban centers radically alter hydrological cycles, causing unintended consequences for the environment, such as the creation of extensive contamination plumes in unconfined aquifers. The Environmental Agency of the State of São Paulo has observed this issue since 1994. Therefore, this study aimed to create a method using nitrate as an indicator of contamination that permits an assertive interpretation of changes in the groundwater quality in monitoring wells of regional networks. The method was applied in ten cities with monitoring wells in the Bauru Aquifer System. The results correlated the presence of nitrate with the time and dynamics of land use in the capture zones of the wells over 54 years (1962-2016). In areas with sewer networks installed before 2001 and urban occupation greater than 60% of urban occupation in the capture zones, there was an increase in nitrate concentration of at least 35%. Likewise, extending this new method to other wells will make it possible to identify the causes of nitrate and other contaminants in the groundwater-monitoring network in the State of São Paulo
Biochemical potential of methane (BMP) of camelid waste and the Andean region agricultural crops
Get PDFThis paper evaluates the anaerobic digestion of agricultural waste, manure and slaughterhouse residues of species typical of the Andes, such as llama, vicuña 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
Demografía de una Palma Hiperclave: Modelamiento Poblacional de Mauritia flexuosa en una parcela en Tena, Amazonía Ecuatoriana
Get PDFMauritia flexuosa es una de las palmas más abundantes de la Amazonía, ocupando parches
dominantes en zonas mal drenadas de diverso origen. Es de notable importancia para el
ecosistema y recientemente se ha propuesto como una especie hiperclave, sumado al
considerable impacto en los ingresos de las comunidades de la región amazónica por el
creciente consumo de sus frutos. Este aprovechamiento se logra comúnmente mediante la
tala de individuos femeninos en los bosques, lo que genera una gran presión sobre las
poblaciones naturales. A pesar de su importancia e histórico uso, se sabe poco sobre su
manejo. En Ecuador, el mercado de M. flexuosa está creciendo y existe interés del estado de
incentivar el uso sostenible de nuestros productos, por lo que el objetivo de este estudio es
evaluar la estabilidad poblacional de la especie e identificar el rango de tamaño que más
contribuye al crecimiento de la población con fines de manejo. Para ello, se estableció en el
año 2016 una parcela permanente de 1 ha en un bosque inundado dominado por M. flexuosa
en la cuenca del río Napo, en la cual se muestrearon 375 individuos. Se registraron
mensualmente las tasas vitales de la población y el crecimiento de cada etapa desde octubre
del 2016 a enero del 2020, y también se determinaron las tasas de producción y germinación.
Para modelar la dinámica poblacional se aplicaron modelos de proyección integral (IPM). Los
resultados muestran un patrón recurrente de dependencia sobre individuos de 4-8 hojas en
las diferentes regiones, y una alta mortalidad en individuos entre 1-5 hojas. La caída de hojas
influenciada indirectamente por la falta de dispersores en el sitio pueden ser un facto
Reproductive ecology of white cacao (Theobroma bicolor Humb. & Bonpl.) in Ecuador, western Amazonia: floral visitors and the impact of fungus and mistletoe on fruit production
No full textTheobroma bicolor is widely distributed in the Neotropics with great potential for economic use. However, very little is available in literature about its pollinators and reproductive ecology in comparison to what is available about its economically more important relative T. cacao. We studied aspects of the floral biology, reproductive phenology and biotic restrictions to the reproduction of the species. We measured, observed and monitored flowers and described their morphology, breeding system, receptivity times of the stigma and peaks of flower and fruit production. During 20 consecutive days, we collected floral visitors of 135 ± 45 flowers per day. We also calculated the damage in fruit production generated by the mistletoe (Oryctanthus cf. alveolatus) and the fungus (Moniliophthora roreri). We found that flower stigma was more receptive between 6:00–10:00 and flowers last up to three days on the tree, which is less time than what has been reported elsewhere. We collected 211 insects from 68 different morphotypes, but five of these represented 49.8% of the total; specimens of Ceratopogonidae, Chironimidae and Sciaridae were the most abundant and could be pollinators of the species. The flowering of T. bicolor showed a positive correlation (r > 0.75) with the months with higher temperature and solar radiation. We recorded an average per tree of 7 ± 5 fruits. We found a drastic loss of 84% of fruits in the plants infested by the mistletoe O. cf. alveolatus and of 29% when infested by the fungus M. roreri. The results of this study serve as a basis to generate local management practices
Use of an Integrated Geochemical and Ecotoxicological Approach to Evaluate Sediment Metal Contamination in Three Protected Estuarine Areas Along the Coast of São Paulo State, Brazil
Get PDFWe compared sediment quality in estuaries at three locations along the coast of São Paulo State, Brazil, using geochemical analyses and whole sediment toxicity tests, during the southern summer and winter of 2013. Each locality is afforded a distinct degree of legal protection, and exhibits a different level of metal pollution: overall, Rio Diana (RD, the most polluted, a Permanent Protection Area) > Rio Itapanhaú (RI, intermediate contamination, an Environmental Protection Area) > Rio Picinguaba (RP, pristine, a State Park). Chronic sediment toxicity tests evaluated reproductive rates of the copepod Nitokra sp. RI sediments showed the highest metal concentrations and toxicity in both seasons. Metal concentrations at RD were low but toxic in summer. RP sediments were not contaminated, suggesting effective legal protection from pollution at this locality. RI and RD, although provided some legal protection, showed clear signs of environmental degradation, emphasizing the need for more effective pollution control
Secondary Lahars Triggered by Periglacial Melting at Chimborazo Volcano, Ecuador
Get PDF: Periglacial melting processes can provide the water source for secondary lahars triggered by volcanic
and/or meteorological phenomena on volcanoes. Between December 2015 and April 2016, four major lahars were
reported southeast of Chimborazo volcano (Ecuador). Fieldwork allowed determining the area (1.670.37 km2),
volume (3E+05 to 7E+05 m3), peak discharge (100 - 150 m3/s) and mean speed (2 - 4 m/s) of these flows, which
affected the local infrastructure and threatened several towns downstream (>1000 inhabitants). This case study
suggests that anomalous periglacial melting could have been induced by: i) an increase in temperatures at periglacial
altitudes partly ascribed to El Niño phenomenon, ii) albedo reduction of the glacier due to ash fallout from
Tungurahua volcano (40 km east of Chimborazo) which erupted from 1999 to 2016 and, iii) a slight increase in
internal activity at Chimborazo prior and during the lahars occurrence, as evidenced by more seismic events and
thermal anomalies. These simultaneous factors could have led to the formation, outburst and/or overflow of
superficial and intra-glacier ponds providing the water source to generate lahars on a dormant volcan
Functional Feeding Groups of Macrofauna and Detritus Decomposition along a Gradient of Glacial Meltwater Influence in Tropical High-Andean Streams
Get PDFTropical Andean glaciers are retreating rapidly, with possible consequences for trophic
structure and ecosystem processes in high Andean meltwater streams. Here, we measured the
environmental characteristics, quantified pools of particulate organic matter (POM) and periphyton
(Chl. a), sampled benthic macroinvertebrates, determined functional feeding groups (FFG), and
performed mesh bag decomposition experiments with Calamagrostis grass detritus at
17 stream sites along a gradient of glacial influence (GI) with 0–23% glacier cover in the catchment at
4050–4200 m a.s.l. in the Andes of Ecuador. POM was unrelated to GI while Chl. a. showed a weak
(non-significant) negative relationship to GI. The macrofauna abundance decreased while taxon
richness and the number of FFGs per site showed a hump-shaped relationship with increasing GI.
Taxa with an opportunistic and generalist feeding mode generally dominated benthic assemblages
and were related to high GI levels and low Chl. a. Only shredders were negatively related to GI, but
unrelated to POM. Decomposition rates were comparable to those found in temperate alpine streams,
and for both fine (0.0010–0.0065; median 0.0028 d−1
) and coarse (0.0019–0.0088; median 0.0048 d−1
)
mesh bags, peaked at intermediate GI values, while the difference between bag types was small and
almost constant along the GI gradient. This indicates an overall minor effect of macroinvertebrate
shredders compared to that of microbes, in particular at high GI. It also suggests that the relatively
high average temperature of these high-altitude equatorial streams (7–10 ◦C) does not produce higher
decomposition rates than those in comparable but colder streams at temperate latitudes. The results
suggest that, at the lower end of glacier cover, tropical glacier loss will not change the dominant
microbial role in detritus decomposition, but that part of the physical abrasion could be partially
replaced by biological shredding
Diseño de una vacuna candidata de múltiples epítopos contra la leishmaniasis cutánea mediante herramientas inmunoinformáticas
Get PDFLa leishmaniasis es una de las principales enfermedades desatendidas del mundo.
De las manifestaciones clínicas de la enfermedad, la leishmaniasis cutánea tiene la
prevalencia más alta, especialmente en Latinoamérica. El tratamiento actual se basa en la
quimioterapia, que es difícil de administrar, costosa e ineficaz por la aparición de
farmacorresistencia. El desarrollo y la administración de una vacuna podría representar
uno de los medios más rentables para controlar esta enfermedad. Sin embargo, hasta la
fecha no se dispone de una vacuna. Los avances recientes en inmunoinformática podrían
ser un enfoque prometedor para identificar candidatos a vacunas debido a que son una
alternativa menos costosa y más óptima respecto a los esfuerzos experimentales.
Se diseñó un péptido de vacuna de múltiples epítopos que consta de epítopos
lineales afines a HLA-I y HLA-II de antígenos y epítopos reportados con potencial
inmunogénico. Los epítopos empleados para el diseño mostraron inmunogenicidad, alta
conservación, no toxicidad y la combinación de estos logró el 93.61% de cobertura
poblacional a nivel mundial. La calidad general de la vacuna se validó por las evaluaciones
de alergenicidad, antigenicidad y parámetros fisicoquímicos. El acoplamiento y simulación
de dinámica molecular del multi-epítope con los receptores TLR y HLA demostraron una
posible interacción y estabilidad de los complejos. Además, la simulación inmune predijo
niveles significativamente altos de INF-γ e IL-2 y poblaciones de células T-helper, T citotóxicos. Aunque los resultados sugieren que el diseño propuesto es comparable a otras
investigaciones in silico, se requiere de evaluaciones in vitro
Selection and isolation defne a heterogeneous divergence landscape between hybridizing Heliconius butterfies
Get PDFHybridizing species provide a powerful system to identify the processes that shape genomic variation and maintain species bound-
aries. However, complex histories of isolation, gene fow, and selection often generate heterogeneous genomic landscapes of di-
vergence that complicate reconstruction of the speciation history. Here, we explore patterns of divergence to reconstruct recent
speciation in the erato clade of Heliconius butterfies. We focus on the genomic landscape of divergence across three contact zones
of the species H. erato and H. himera. We show that these hybridizing species have an intermediate level of divergence in the
erato clade, which fts with their incomplete levels of reproductive isolation. Using demographic modeling and the relationship
between admixture and divergence with recombination rate variation, we reconstruct histories of gene fow, selection, and demo-
graphic change that explain the observed patterns of genomic divergence. We fnd that periods of isolation and selection within
populations, followed by secondary contact with asymmetrical gene fow are key factors in shaping the heterogeneous genomic
landscapes. Collectively, these results highlight the effectiveness of demographic modeling and recombination rate estimates to
disentangling the distinct contributions of gene fow and selection to patterns of genomic divergence
Análisis de Susceptibilidad al Deslizamiento utilizando el Proceso de Jerarquía Analítica (AHP) en SIG en el tramo vial Puyo – Tena
Get PDFLa carretera Puyo – Tena es propensa a deslizamientos de tierra debido a la dinámica,
geomorfología y materiales geológicos del sector. El presente trabajo tuvo como objetivo
generar un mapa de susceptibilidad al deslizamiento enfocándose exclusivamente en esta
vía. Para la presente investigación, se analizó seis variables: pendiente, formaciones
geológicas, distancias (fallas, carretera y ríos) y por último la cobertura y uso de la tierra.
Se jerarquizó y ponderó cada una de las variables con el proceso de jerarquía analítica para
conocer sus grados de incidencia al deslizamiento. El mapa de susceptibilidad al
deslizamiento fue el resultado de la combinación lineal ponderada de las seis capas
temáticas realizadas a partir de las seis variables analizadas; y fue reclasificado en cinco
clases de susceptibilidad: muy baja, baja, moderada, alta y muy alta. El mapa final mostró
que 16.53% (25.38 Km2
) del área de estudio presentaron categorías entre alta y muy alta
susceptibilidad; lo cual los hace muy probable a deslizamientos. Además, los resultados
mostraron que 17 Km de los 80 Km de la vía Puyo – Tena cuentan con gran probabilidad a
deslizamientos, es decir un 22% de la vía. Por último, se determinó que existen quince
zonas de mayor probabilidad al deslizamiento por situarse en zonas de alta pendiente,
litología porosa y permeable, gran cantidad de ríos y suelos agrícolas. El mapa de
susceptibilidad permitirá tomar decisiones para mitigar posibles eventualidades que
pongan en riesgos a transportistas, bienes materiales y habitantes del sector