Repositorio Digital Ikiam (Univ. Regional Amazónica)
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Editorial: Perspectives on energy futures, environment and wellbeing
Get PDF“We tend to think of development, not in terms of evolution, but interms of creation. [...] If we talk of promoting development, whathave we in mind: goods or people?”(Schumaker, 1989)Schumaker (1989)raises doubts about whether the so-called soci-etal development is oriented to an individual and/or collective evolu-tion in its deeper meaning, or oriented to material creation. Develop-ment is a widely used term mostly without establishing a properlysemantic, usually to sustain the business-as-usual production-con-sumption behavior claimed as mandatory to societal development.However, the ultimate goal of such behavior is to keep with the ma-terial flow and increase the gross economic product rather than a de-velopment focused on evolution of human beings in their complexfeatures. Such a production-consumption pattern causes pressure onenergy and environmental security (as a provider of resources and re-ceiver of sub products for dilution), which deserves special attention bypolicy makers when promoting societal development. Currently, energypolicies are demanding a reduction in greenhouse gases and toxicemissions, because increased development based on resource ..
Lotus japonicusTriterpenoid Profile and Characterization oftheCYP716A51andLjCYP93E1Genes Involved in TheirBiosynthesis In Planta
Get PDFLotus japonicusis an important model legume plant in sev-eral fields of research, such as secondary (specialized) me-tabolism and symbiotic nodulation. This plant accumulatestriterpenoids; however, less information regarding its com-position, content and biosynthesis is available comparedwithMedicago truncatulaandGlycine max. In this study,we analyzed the triterpenoid content and composition ofL. japonicus.Lotus japonicusaccumulated C-28-oxidized tri-terpenoids (ursolic, betulinic and oleanolic acids) and soya-sapogenols (soyasapogenol B, A and E) in a tissue-dependentmanner. We identified an oxidosqualene cyclase (OSC) andtwo cytochrome P450 enzymes (P450s) involved in triter-penoid biosynthesis using a yeast heterologous expressionsystem. OSC9 was the first enzyme derived fromL. japonicusthat showeda-amyrin (a precursor of ursolic acid)-produ-cing activity. CYP716A51 showed triterpenoid C-28oxidation activity. LjCYP93E1 convertedb-amyrin into24-hydroxy-b-amyrin, a metabolic intermediate of soyasapo-genols. The involvement of the identified genes in triterpen-oid biosynthesis inL. japonicusplants was evaluated byquantitative real-time PCR analysis. Furthermore, geneloss-of-function analysis ofCYP716A51andLjCYP93E1wasconducted. Thecyp716a51-mutantL. japonicushairy rootsgenerated by the genome-editing technique produced no C-28 oxidized triterpenoids. Likewise, the complete abolitionof soyasapogenols and soyasaponin I was observed in mutantplants harboringLotus retrotransposon 1(LORE1)inLjCYP93E1. These results indicate that the activities ofthese P450 enzymes are essential for triterpenoid biosynthe-sis inL. japonicus. This study increases our understanding oftriterpenoid biosynthesis in leguminous plants and providesinformation that will facilitate further studies of the physio-logical functions of triterpenoids usingL. japonicus
Potential use of 13-mer peptides based on phospholipase and oligoarginine as leishmanicidal agents
Get PDFPhospholipase A2 toxins present in snake venoms interact with biological membranes and serve as structural
models for the design of small peptides with anticancer, antibacterial and antiparasitic properties. Oligoarginine peptides are capable of increasing cell membrane permeability (cell penetrating peptides), and for this reason are interesting delivery systems for compounds of pharmacological interest. Inspired by these two families of bioactive molecules, we have synthesized two 13-mer peptides as potential antileishmanial leads gaining insights into structural features useful for the future design of more potent peptides. The peptides included p-Acl, reproducing a natural segment of a Lys49 PLA2 from Agkistrodon contortrix laticinctus snake venom, and its p-AclR7 analogue where all seven lysine residues were replaced by arginines. Both peptides were active against promastigote and amastigote forms of Leishmania (L.) amazonensis and L. (L.) infantum, while displaying low cytotoxicity for primary murine macrophages. Spectrofluorimetric studies suggest that permeabilization of the parasite's cell membrane is the probable mechanism of action of these biomolecules. Relevantly, the engineered peptide p-AclR7 was more active in both life stages of Leishmania and induced higher rates of ethidium bromide incorporation than its native template p-Acl. Taken together, the results suggest that short peptides based on phospholipase toxins are potential scaffolds for development of antileishmanial candidates. Moreover, specific
amino acid substitutions, such those herein employed, may enhance the antiparasitic action of these cationic
peptides, encouraging their future biomedical applications
A human role in Andean megafaunal extinction?
No full textA new fossil pollen, Sporormiella, and sediment chemistry record from Lake Llaviucu, Ecuador, spanning the period from 16,280–9000 years Before Present, provides a high-resolution record of paleoecological change in the high Andes. The deglacial transition from super-páramo through páramo grasslands, to Andean forest is traced, with near-modern systems being established by c. 11,900 years ago. It is suggested that forest elements probably existed in microrefugial populations close to the ice front. Sporormiella is used as a proxy for megafaunal abundance, and its decline to background levels is inferred to indicate a local extinction event at c. 12,800 years ago. About 1800 years prior to the extinction, charcoal becomes a regular sedimentary component in this very wet valley. An early date for human activity in the valley is suggested, with the direct implication of humans in the extinction of the megafauna
A review on crocodilian nesting habitats and their characterisation via remote sensing
Get PDFCrocodilians usually remain inside or near their nests during most vulnerable life stages (as eggs, neonates and reproductive females). Thus, protection of nesting sites is one of the most appropriate conservation actions for these species. Nesting sites are often found across areas with difficult access, making remote sensing a valuable tool used to derive environmental variables for characterisation of nesting habitats. In this study, we (i) review crocodilian nesting habitats worldwide to identify key variables for nesting site distribution: proximity to open-water, open-water stability, vegetation, light, precipitation, salinity, soil properties, temperature, topography, and flooding status, (ii) present a summary of the relative importance of these variables for each crocodilian species, (iii) identify knowledge gaps in the use of remote sensing methods currently used to map potential crocodilian nesting sites, and (iv) provide insight into how these remotely sensed variables can be derived to promote research on crocodilian ecology and conservation. We show that few studies have used remote sensing and that the range of images and methods used comprises a tiny fraction of what is available at little to no cost. Finally, we discuss how the combined use of remote sensing methods – optical, radar, and laser – may help overcome difficulties routinely faced in nest mapping (e.g., cloud cover, flooding beneath the forest canopy, or complicated relief) in a relevant way to crocodilians and to other semiaquatic vertebrates in different environments
Reproductive phenology variation of the multiple inflorescence-palm tree Wettinia maynensis in relation to climate, in a Piedmont forest in western Amazonia
Get PDFWettinia maynensis is a piedmont palm tree whose ecology, phenology and responses to climate are yet unknown. In order to examine the reproductive biology of this species, we observed the flowering and fruiting performance of 101 adult palms in the Colonso Chalupas Biological Reserve in the Ecuadorian Piedmont, located between the Andean mountains and the Amazon. All individuals were monitored every 1 or 2 months during 2.3 years (2015–2018). The inflorescences are infrafoliar with usually one central, large, pistillate and several lateral, centrifugally smaller, staminate inflorescences. Flowering took place throughout the year although staminate and pistillate inflorescences showed low synchrony towards the end of the year, 40% and 32%, respectively. Staminate inflorescences showed a negative strong relationship with relative humidity and a positive one with temperature. The infructescences exhibited high synchrony (80%) for almost 6 months. Compared to other species of the genus, W. maynensis presented the lowest ratio of male/female inflorescences, the higher production of infructescences but lower number of fruits per year. Infructescences production per palm was between cero and 7, and the time elapsed between the fruit formation and its dehiscence was about 5–8 months. Some palms were observed with simultaneously active pistillate and staminate inflorescences (21–22 palms), therefore geitonogamy is not discarded. Wettinia maynensis inflorescences production and its correlation with relative humidity, hence with temperature, highlights that crucial changes could occur in the reproductive phenology of this species under future climate change scenarios affecting the population dynamics and then the community of Andean–Amazon piedmont forests
Collective aggr essiveness limits colony persistence in high but not low elevation sites in amazonian social spiders
Get PDFIdentifying the traits that foster group survival in contrasting environments is important for understanding local adaptation in social systems. Here we evaluate the relationship between the aggressiveness of social spider colonies and their persistence along an elevation gradient using the Amazonian spider, Anelosimus eximius. We found that colonies of A. eximius exhibit repeatable differences in their collective aggressiveness, and that colony aggressiveness is linked with persistence in a site-specific manner. Less aggressive colonies are better able to persist at high-elevation sites, which lack colony-sustaining large-bodied prey, whereas colony aggression was not related to chance of persistence at low-elevation sites. This suggests resistance to resource limitation through docility promotes colony survival at high elevations. These data reveal that the collective phenotypes that relate to colony persistence vary by site, and thus, the path of social evolution in these environments is likely to be affected
High mosquito diversity in an Amazonian village of Ecuador, surrounded by a Biological Reserve, using a rapid assessment method
Get PDFThis research represents a study in an Amazonian village that has similar structures to others Kichwa Amazonian villages of Ecuador. We evaluated the diversity, ecology, possibility of mosquitoes/pathogens translocation from forest to urban area, and the vulnerability by potential mosquito vectors of diseases through an intensive and fast method done January 2017. Our analyses registered a high diversity of mosquitos in Limoncocha village (33 spp, H’ 2.76), which includes four new records of species for Ecuador. We propose the biological reserve and the lagoon are determinant environmental factors for the high mosquito diversity, plus the socio- economic characteristics related with a deficient water pipeline supply and lack of solid waste system. Furthermore, the high diversity of sylvan mosquitoes registered throughout the area, that include several potential vectors, suggest a moderate to high vulnerability for the transference of pathogens from the Biological Reserve to the urbanized area, which may increase the circulation of little-known arboviruses (Mayaro, Ilheus, St Louis encephalitis) across Ecuador.Journal of Entomogical and Acarological Researc
Going north and south: The biogeographic history of two Malvaceae in the wake of Neogene Andean uplift and connectivity between the Americas
Get PDFThe evolution of the tropical lowland forests in northern South America is poorly understood, yet new insights into past composition and changes through time can be obtained from the rich and diverse fossil pollen record. Here we present a revision of two diagnostic Malvaceae taxa from the Cenozoic record of northern South America and we relate their evolutionary history to recently updated geological models. In our study we review the pollen morphology and botanical affinity of Rhoipites guianensis and Malvacipolloides maristellae, and integrate these data into a phylogenetic framework. We also produce distribution maps for both fossil and extant taxa, infer the phylogeny and historical biogeography of the lineages to which they belong, and identify their ecological associates and environmental settings. The closest extant relatives of Rhoipites guianensis (Grewioideae) are Vasivaea and Trichospermum, which are taxa of South American origin. During the late Eocene to early Miocene Rhoipites guianensis was widely distributed in the lowland floodplain environments of northern South America. The closest living relatives of Malvacipolloides maristellae (Malvoideae) are members of Abutilinae (e.g., Abutilon, Bakeridesia, Callianthe and Herissantia), which have their origin in the northern hemisphere. This taxon makes its first appearance in the fossil record of northern South America during the early Miocene, and is typically found in fresh water floodplain and lacustrine environments. Our study suggests that both taxa migrated across the Central American Seaway in the early Miocene (around 18 Ma), and virtually disappeared from the fossil record in northern South America during the middle Miocene, coinciding with Andean uplift. However, their descendants expanded and -in the case of the Abutilinae—diversified in the Andes. We conclude that the biogeographic history of these Malvaceae is influenced by Andean uplift and the incipient bridging of the Americas. Thereafter, climate change and diversification of the Andean landscape enabled their descendants to move upslope and into the Andes.Review of Palaeobotany and Palynology - ScienceDirec
Hacia Un Manejo Adaptativo de la Reserva Biológica Colonso Chalupas y su Zona de Amortiguamiento: Sistematización de la aplicación de la metodología Manejo Adaptativo de Riesgo y Vulnerabilidad en Sitios de Conservación (MARISCO)
Get PDFLa Universidad Regional Amazónica Ikiam inició sus
actividades en octubre de 2014 como una universidad
pública orientada al estudio e investigación en Ciencias de
la Vida y de la Tierra. Ese mismo año se creó la Reserva
Biológica Colonso Chalupas (RBCC), con 93.246 ha y al
menos seis ecosistemas. La RBCC es el laboratorio vivo
de la Universidad, en la que nuestro personal lleva a cabo
investigaciones en diferentes áreas de las ciencias de la
vida y de la tierra.
Con el objetivo de formalizar la relación de Ikiam con
la reserva, el 16 de diciembre de 2016 se suscribió un
convenio de cooperación interinstitucional entre el
Ministerio del Ambiente y la Universidad Regional
Amazónica Ikiam con el objetivo de:
Gestionar de manera efectiva, sostenible y científica
la Reserva Biológica Colonso Chalupas, a través de la
participación de la Universidad Regional Amazónica Ikiam
en su manejo, protección y administración en cumplimiento
a la normativa legal vigente y las regulaciones de la
autoridad ambiental.
Siguiendo el enfoque del ecólogo C.S. Holling, quien
introdujo los conceptos de resiliencia ecológica y de
manejo adaptativo, Ikiam ha trabajado, en el marco del
proyecto tripartito AECID-UNESCO-Ikiam, en el plan
de manejo de la reserva así como en otros componentes
necesarios como el Plan de Comunicación, Educación y
Participación Ambiental (CEPA). Gracias a este proyecto
se ha conseguido construir una estación científica a
unos 1550 msnm, que ha servido de apoyo para la
investigación multidisciplinar en la reserva (fauna, flora,
absorción de carbono, nutrientes, suelo, etc.) así como
para el monitoreo diario de su clima. En el marco de este
proyecto se está construyendo de manera participativa el
plan de manejo.
Es en este sentido que quiero agradecer la oportunidad
ofrecida por la Cooperación Técnica Alemana (GIZ),
en asociación con el Ministerio del Ambiente, para
aplicar la metodología de Manejo Adaptativo de Riesgo
y Vulnerabilidad en sitios de Conservación (MARISCO)
a la RBCC y, de esta manera, contribuir al plan de
manejo. La metodología ha permitido reconocer el estado
de ciertos ecosistemas de la reserva, las amenazas que
enfrentan, los factores que contribuyen a exacerbar dichas
amenazas y así priorizar áreas y formular estrategias y
actividades para su conservación.
Ikiam ha participado en esta aplicación de MARISCO
con investigadores que acumulan experiencia en
ecosistemas terrestres de la Amazonía, ecosistemas
acuáticos, de alta montaña, así como en clima y ecología
del paisaje, lo que ha permitido que supongan un fuerte
apoyo a esta iniciativa.
Tres de los talleres de MARISCO se han celebrado
en Ikiam, en los que han participado actores locales
de diversas instituciones y comunidades, quienes
han contribuido activamente a la identificación de
problemáticas, así como de posibles soluciones.
La sistematización y compilación de estos talleres (tanto
en la parte baja como en la parte alta de la reserva) es
de suma importancia para el plan de manejo y para las
actividades de investigación. Las prioridades identificadas
deben iluminar el plan de investigación de la universidad
en cuanto a la reserva, de tal manera que avancemos en
nuestro compromiso de conocer, proteger y divulgar el
patrimonio natural que contiene la Reserva Biológica
Colonso Chalupas