Repositorio Digital Ikiam (Univ. Regional Amazónica)
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Analysis of endemism of world arthropod distribution data supports biogeographic regions and many established subdivisions
No full textWe analyzed 769 242 occurrence records for 115 424 species of terrestrial arthropods, from three biodiversity repositories (Global Biodiversity Information Facility (GBIF), Natural History Museum, London, and “Sistema de Informação Distribuído para Coleções Biológicas” (SpeciesLink)), to test the use of global‐scale data points for quantitative assessments of areas of endemism. The data include Insecta (105,941 species), Arachnida (7984 species), Myriapoda (1229) and terrestrial crustaceans (270 Branchiopoda). The species were assigned to 14 543 higher taxonomic groups because such groups often characterize larger areas of endemism. Putative areas of endemism were visualized as sets of cells displaying unique groups of species without the assumption of hierarchical relationships. Yet, the use of 10° grid cells recovered many large areas broadly corresponding to biogeographic Regions (Nearctic, Neotropical, Panamanian, Palaearctic, Afrotropical, Australian, Oceanian and Oriental) albeit with the limits poorly defined. An analysis of 5° grids resulted in 306 sets included in the different biogeographic Realms: Afrotropical, Australian, Madagascan, Nearctic, Neotropical, Oceanian, Oriental, Palaearctic, Saharo‐Arabian and Sino‐Japanese. The Panamanian Realm comprises 89 partly overlapping sets, crossing the Nearctic and Neotropical boundaries. A total of 7338 species of Insecta were endemic to some areas (Sino‐Japanese, Afrotropical, Panamanian, Palaearctic, among others), followed by Arachnida (412 spp) and 105 species in other clades ranked as “classes”. Six sets were supported only by genera, except for Panamanian sets that were supported by genera and families. Many of the species in the dataset are included in IUCN red lists, but probably most of those have distributions more restricted than global areas of endemism; only 102 appear as endemic to some area (Neartic, Madagascan, Panamanian, Afrotropical, among others). The results show that data from global databases can be used to identify areas of endemism on a worldwide basis but—owing to their incompleteness—only at a relatively coarse level. At the level of resolution currently allowed by such databases, such global studies are only complementary to studies where areas are determined subjectively by systematists (instead of actual point records), or studies using point records in datasets for specific taxonomic groups curated and compiled by specialists
Ultrafiltración de agua superficial con fines de reutilización: mecanismos de taponamiento de membrana
Get PDFLa ultrafiltración es una alternativa de potabilización a partir de agua superficial de gran
interés debido a la creciente demanda mundial de agua dulce. Sin embargo, el
ensuciamiento de membrana es uno de sus principales desafíos, porque reduce el
rendimiento de permeado y la vida útil de los filtros de membrana. El objetivo de la
presente tesis es dilucidar los mecanismos de bloqueo de poro en membranas con
distinto corte molecular (100, 30 y 10 kDa) durante ultrafiltración a presión constante
de agua superficial, de modo que se puedan sugerir procesos de limpieza para extender
su vida útil. Las muestras fueron colectadas en una sección del río Tena (Napo, Ecuador)
previa a la zona urbana de la ciudad con el mismo nombre. Se cuantificaron los
principales parámetros físico-químicos del agua cruda y del efluente de ultrafiltración
con membranas de 100, 30 y 10 kDa. A través de modelado matemático, se identificó la
secuencia de bloqueo de poro que sigue cada membrana. Se reportan modelos
combinados que comienzan con bloqueo intermedio, seguidos de bloqueo estándar y
completo (o viceversa), y terminan en la formación de torta. Para todas las membranas,
la disminución del flujo se relacionó con los mecanismos de bloqueo durante las
primeras etapas, y con la formación de torta durante las últimas etapas de filtración. En
base a los resultados de resistencia específica, porosidad, altura, dimensión fractal de la
torta y tasas de acumulación de componentes físico-químicos, se propone una teoría de
formación del biofouling. El análisis de los mecanismos de bloqueo en relación a las
propiedades hidráulicas y estructurales de la torta, destacan su relevancia en el
ensuciamiento irreversible y elección del método de limpieza de membran
Macrohongos silvestres comestibles utilizados por dos comunidades kichwa del Napo, Amazonía Ecuatoriana
Get PDFEcuador es un país multicultural y megadiverso. Entre los 18 pueblos indígenas que habitan el
territorio, al menos 12 utilizan cerca de 50 especies de hongos comestibles silvestres (HCS).
Los estudios indican que los kichwas del Amazonas son los que más usan, con 29 especies. Sin
embargo, se desconocen aspectos de la ecología de las especies, como las temporadas de
fructificación, los sustratos, las especies vegetales relacionadas con ellas, así como las
preferencias de uso de los habitantes. Con el fin de contribuir con información ecológica y
etnomicológica sobre los HSC utilizados por el pueblo amazónico kichwa, se estudió la riqueza
de hongos comestibles consumidos por dos comunidades kichwa asentadas en la zona de
amortiguamiento de la Reserva Biológica Colonso Chalupas. Entre mayo de 2019 y marzo de
2020 entrevistamos a los adultos de las comunidades, caminamos con ellos por el bosque,
recogimos las especies de hongos comestibles, evaluamos la importancia cultural, observamos
los sustratos asociados a las especies y las preferencias de uso por parte de los habitantes.
Entre mayo de 2019 y marzo de 2020 entrevistamos a los adultos de las comunidades,
caminamos con ellos por el bosque, recogimos las especies de hongos comestibles, evaluamos
la importancia cultural, observamos los sustratos asociados a la especie y registramos los
momentos de fructificación. Se encontraron doce especies de hongos: 11 basidiomicetos y un
ascomiceto; seis especies son nuevos registros para el grupo kichwa y cuatro especies se
añaden a la lista de especies del país. Tres especies Favolus tenuiculus (215,35), Favolus sp.1
(153,47) y Lentinus concavus (117,70) fueron las preferidas por las comunidades. Los hongos
se encontraban en los troncos de 22 especies de plantas que crecen especialmente en los
chagras. Este es el primer estudio etnomicológico en la zona de amortiguamiento de la reserva
y servirá como línea base para estudios de prospección para el uso sostenible de este recurs
Diversity and synanthropy of flies (Diptera: Calyptratae) from Ecuador, with new records for the country
Get PDFAbstract: The Calyptratae are one of the most diverse groups of Diptera. Some species have immature states involved in the decomposition
of organic matter of animal origin (i.e., they are sarcosaprophagous). In this study, we examined the diversity and synanthropy of
sarcosaprophagous calyptrates in several environmental zones of the Ecuadorian Andes. Captures were performed in an urban zone
located in the Tocachi community with monocultures (MC) and polycultures (PC), a rural zone with an agroecological farming system (AFS),
and a forest zone with a montane forest located in the Parque Arqueológico Cochasquí (PAC) and the Cochasquí montane forest (CMF). A
total of 2,925 specimens of Calyptratae were collected, representing 38 morphotypes and 17 species. Four are new reports for Ecuador:
Dolichophaonia trigona (Shannon & Del Ponte), Phaonia trispila (Bigot), Compsomyiops melloi Dear, and Calliphora lopesi Mello. CMF and
PAC presented high abundance and richness, followed by AFS, MC, and PC; PAC showed the highest diversity, in contrast to lowest in MC;
the evenness decreased from forest to urban zones. Species that exhibited a preference for human settlements (positive synanthropic
index) included Limnophora marginata Stein, Phaonia trispila, Lucilia cuprina (Wiedemann), Calliphora lopesi, Compsomyiops melloi, and
Calliphora nigribasis Macquart. Those with a preference for uninhabited areas (negative index) included Tricharaea sp1, Sarconesiopsis
magellanica (Le Guillou), and Sarconesia chlorogaster (Wiedemann)
What Drives Household Deforestation Decisions? Insights from the Ecuadorian Lowland Rainforests
Get PDFTropical forests, and more concretely, the Amazon Basin and the Chocó-Darién, are highlyaffected by deforestation activities. Households are the main land-use decision-makers and are keyagents for forest conservation and deforestation. Understanding the determinants of deforestation atthe household level is critical for conservation policies and sustainable development. We explore thedrivers of household deforestation decisions, focusing on the quality of the forest resources (timbervolume potential) and the institutional environment (conservation strategies, titling, and governmentalgrants). Both aspects are hypothesized to influence deforestation, but there is little empirical evidence.We address the following questions: (i) Does timber availability attract more deforestation? (ii) Doconservation strategies (incentive-based programs in the Central Amazon and protected areas inthe Chocó-Darién) influence deforestation decisions in household located outside the areas underconservation? (iii) Does the absence of titling increase the odds of a household to deforest? (iv) Cangovernmental grants for poverty alleviation help in the fight against deforestation? We estimated alogit model, where the dependent variable reflects whether or not a household cleared forest withinthe farm. As predictors, we included the above variables and controlled by household-specificcharacteristics. This study was conducted in the Central Amazon and the Chocó-Darién of Ecuador,two major deforestation fronts in the country. We found that timber volume potential is associatedwith a higher odds of deforesting in the Central Amazon, but with a lower odds in the Chocó-Darién.Although conservation strategies can influence household decisions, the effects are context-dependent.Households near the incentive-based program (Central Amazon) have a lower odds of deforesting,whereas households near a protected area (Chocó-Darién) showed the opposite effect. Titling is alsoimportant for deforestation reduction; more attention is needed in the Chocó-Darién where numeroushouseholds are living in untitled lands. Finally, governmental grants for poverty alleviation showedthe potential to generate positive environmental outcomes
An integrative approach to identify the impacts of multiple metal contamination sources on the Eastern Andean foothills of the Ecuadorian Amazonia
Get PDFCurrently, several concerns have been raised over metal contamination in the upper Amazon basin. Rivers that flow from the high Andes to the lowland Amazon are threatened by anthropogenic activities, which may, in turn, lead to increased metal concentrations in both water and sediments. In the present study, the impacts of multiple metal contamination sources in these ecosystems were identified. The degree of metal contamination was assessed in water and sediment and seed phytotoxicity analyses were carried out in samples taken from 14 sites located in upper Napo River tributaries, combining geochemical and ecotoxicological techniques. These tributaries were chosen based on their degree of anthropogenic contamination and proximity to known sources of relevant pollution, such as small-scale gold mining (MI), urban pollution (UP), fish farming (FF) and non-functional municipal landfill areas (LF). Our results suggest that anthropogenic activities are introducing metals to the aquatic ecosystem, as some metals were up to 500 times above the maximum permissible limits for the preservation of aquatic life established by Ecuadorian and North American guidelines. Sites located close to small-scale gold mining and sanitary landfills presented 100 to 1000 times higher concentrations than sites classified as “few threats”. In water, Cd, Pb, Cu, Zn and Hg were mostly above the maximum permissible limits in the samples, while Cd in sediment reached concentrations 5-fold above the probable effect level (PEL). Phytotoxicity was associated through the diffuse contamination present in urban and landfill areas. Overall, metal concentrations and phytotoxicity assessments suggest anthropogenic effects to environmental contamination, even though natural sources cannot be disregarded. Anthropogenic effects in the eastern Andean Rivers need to be constantly monitored in order to build a complete picture on how pollution sources may affect this strategic Amazon basin area
Evaluation of municipal solid waste management system of Quito -Ecuador through life cycle assessment approach
Get PDFIn Latin America and the Caribbean, the suitable processing of waste through the use oflandfills is around 55%, while the local governments with municipal solid waste (MSW) management plans are around 20%. In Quito, for instance, approximately 2000 ton/day of solid waste are collected, and disposed in El Inga Landfill. The objective of thisstudy is evaluating the MSW management of Quito through Life Cycle Assessment (LCA) approach. For achieving this goal, the ISO 14040 methodology was followed and SimaPro 8.4 was used as analysis software. The functional unit used is 1 ton of MSW, while, the material of study was the waste generated in households, commercial sector, schools and markets; whose values were obtained by the public companies EMASEO-EP, EMGIRS-EP, as well as from the open-access data of the city. The results show that using of biogas from the landfill allows the maximum saving of greenhouse gases (GHG) emissions. Therefore, the biogas plant is the process with less environmental impact. The compaction and transportation of MSW displayed a slightly higher impact comparing with theprevious process, presenting the second-best environmental performance. On the other hand, the leachate treatment shows the greatest environmental impact according to the model, despite of the effluents does not exceed the permissible limits of the environmental Ecuadorian legislation. The researchers consider suitable the analysis of composting and anaerobic digestion techniques as complementary options to reduce this environmental impact, due to the high organic fraction in the analyzed waste
Variación bioquímica y toxicológica de venenos de Bothrops atrox en la Amazonía ecuatoriana: implicaciones clínicas y terapéuticas
Get PDFBothrops atrox es la especie de serpiente venenosa que ocasiona la mayor cantidad
de accidentes ofídicos en la Amazonía ecuatoriana. Pese a su importancia clínica, la
composición y actividades de su veneno han sido escasamente estudiadas en el país. Por
otra parte, varios trabajos han documentado la presencia de variaciones bioquímicas a
nivel interespecífico e intraespecífico en el veneno de B. atrox. Considerando las
implicaciones clínicas que pueden derivar de la variación bioquímica y toxicológica, el
presente trabajo tuvo como objetivo realizar la caracterización de venenos de individuos
B. atrox de la Amazonía ecuatoriana. Los perfiles bioquímicos de los venenos obtenidos
mediante RP-HPLC y electroforesis y la caracterización enzimática evidenciaron la
presencia de diferencias a nivel poblacional e individual. En los ensayos toxicológicos se
evidenciaron variaciones significativas al comparar las actividades de muestras colectadas
en distintas localidades. El antiveneno polivalente tuvo una eficiencia satisfactoria ante los
efectos hemorrágicos y letales, con excepción de dos venenos, para los que se requirieron
dosis altas. Finalmente, el análisis de las características del envenenamiento de B. atrox en
pacientes hospitalarios demostró la presencia de variaciones en los signos y síntomas
reportados, así como algunas complicaciones derivadas del evento. En general, el
tratamiento con antiveneno tuvo un desempeño satisfactorio y baja frecuencia de
reacciones adversas. Sin embargo, la variabilidad en las manifestaciones clínicas y altas
dosis de suero antiofídico requeridas, tanto en los datos de laboratorio como en pacientes
hospitalarios, señalan la necesidad de realizar más estudios similares a este
From the Atlantic forest to the Ecuadorian Andes: Phylogeny and biogeography of a new species of Atopophrynus, an incertae sedis lineage
Get PDFLa historia geológica de América del Sur ha impulsado la diversificación de especies
neotropicales, a través de eventos de dispersión, vicarianza y extinciones como resultado de
los cambios en la orogenia de la región. Un grupo neotropical que responde a los cambios
geológicos relacionados con la elevación de los Andes son los anfibios (Anura). En este
estudio, se discute la historia biogeográfica de Atopophrynus, considerado como incertae
sedis dentro de Brachycephaloidea, además de describir una nueva especie de los Andes en
Ecuador en base a en evidencia genética y morfológica. Se recuperó la posición filogenética
de Atopophrynus usando ADN mitocondrial y nuclear, a través de análisis bayesiano y de
máxima verosimilitud. Adicionalmente, el tiempo de divergencia de los taxones hermanos
incluye la información calibrada en tiempo geológico, para contrastar el papel de la orogenia
de América del Sur sobre su diversificación en los últimos 65 Ma. En un contexto más amplio,
se analizó la historia biogeográfica usando una reconstrucción de áreas ancestrales por áreas
biogeográficas, incorporando un análisis estadístico de dispersión y vicarianza. Los análisis
filogenéticos revelan que Atopophrynus está relacionado con Crossodactylus, perteneciente a
la familia Hylodidae, un grupo distribuido a lo largo del bosque Atlántico sur oriental de
Brasil. La monofilia de Hylodidae no está respaldada por los resultados, por lo que es
necesario incorporar información adicional para comprender las relaciones filogenéticas y la
taxonomía del grupo. De manera interesante, la nueva especie es parte de uno de los clados
más antiguos de Anura, con un origen sudamericano que se remonta a aproximadamente
33,48 millones de años. Se sugiere que los cambios paleogeológicos en América del Sur
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promovieron su especiación, donde se identifican dos eventos de dispersión y vicarianza
desde el Escudo Brasileño hasta el noroeste de los Andes, en el Paleógeno
Warning about conservation status of forest ecosystems in tropical Andes: National assessment based on IUCN criteria
Get PDFWorld ecosystems are suffering from anthropogenic and natural pressure. The IUCN (International
Union for Conservation of Nature) has developed analogous criteria for the Red List
of Threatened Species in order to perform similar risk assessments on ecosystems, creating
the Red List of Ecosystems (RLE) methodology. One of the most significant challenges for
the construction of these lists is gathering the available information to apply the criteria. By
applying IUCN RLE criteria B (the extent of restricted geographic distribution of an ecosystem),
we analyzed the threat level of 64 forest ecosystems of the Ecuadorian mainland.
According to the results, limited distribution is the key risk to threatened ecosystems, which
are associated with anthropogenic pressures. Our study showed that 22% of forest ecosystems
are classified as threatened. This evaluation of the forest ecosystem status at a
national level could lead to public awareness towards ecosystem conservation and provide
reasonable strategies to managers