Centro de Investigación de la Biodiversidad y Cambio Climático

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Universidad Indoamérica

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Performance Evaluation of sCO2–Hydrocarbon Mixtures in SBC-PTES Systems: A Parametric Thermo-Economic Study
(MDPI AG, 2026-04-22)
Tafur-Escanta, Paul
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Garzón-Pérez, Luis
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Barrera-Cifuentes, Lizbeth
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Coco-Enriquez, Luis
;
Valencia-Chapi, Robert
The development of efficient and economically viable energy storage technologies is key to the integration of renewable energies. This study evaluates the thermo-economic performance of hydrocarbons as working fluids in PTES systems based on a simple Brayton cycle (SBC). Different hydrocarbon mixtures are analyzed to determine their impact on efficiency and costs, identifying optimal operating conditions and combinations that improve system performance and viability. The objective is to identify the optimal candidate and operating conditions for enhanced cost-effectiveness. A multivariable optimization was performed using a validated thermodynamic model, integrated with an economic evaluation framework. Key decision variables included pressure ratios, turbine inlet temperatures, and heat exchanger performance parameters, while several sCO2–hydrocarbon mixtures were evaluated as working fluids. Energy and exergy analyses were coupled with component-level cost correlations to determine round-trip efficiency, specific investment cost, and levelized cost of storage. The findings indicate that the CO2/C2H6 (60/40) mixture provides the best overall performance, achieving a round-trip efficiency of 54.38% and a levelized cost of storage of 137.1 $/MWh, outperforming pure CO2. Fluid selection exerts a substantial influence on both thermodynamic and economic indicators, with performance exhibiting a pronounced dependency on critical temperature, molecular complexity, and operating pressure levels. Sensitivity analyses indicate that improvements in heat exchanger effectiveness and turbomachinery efficiency yield substantial reductions in total system cost. The findings indicate that the appropriate alignment of hydrocarbon properties with system design parameters can significantly enhance the feasibility of PTES, offering a technically viable and economically competitive pathway for large-scale energy storage applications. © 2026 by the authors.
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Compiling and analyzing the non-native flora of a megadiverse Neotropical country: a new catalogue for continental Ecuador
(2025)
Ileana Herrera
;
Anahí Vargas
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Kimberly Rizzo
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Zhofre Aguirre
;
Isabella Dillon
In this study, we provide a comprehensive and updated inventory of the non-native vascular flora of continental Ecuador and analyze its key biogeographic and ecological attributes to inform biological invasion management. We recorded 486 non-native wild plant taxa, 52% of which are naturalized and 48% casual. This inventory was primarily based on secondary data (published literature, scientific reports, and online databases) and enriched through fieldwork and expert consultations. It includes information on taxonomy, life form, lifespan, origin, first year of record, and spatial-temporal distribution. The most represented families were Poaceae (16%), Asteraceae (10%), and Fabaceae (9%). About 60% of the taxa originated from Asia and/or Africa, and 67% are herbs. The earliest introductions date back to the late 18<jats:sup>th</jats:sup> century, with an exponential increase beginning in ca. 1915. Only 13% of the taxa have a minimum residence time exceeding 125 years. The Andes accounted for the highest number of taxa (93%, including taxa shared with other regions). Nearly 80% of the non-native taxa have documented uses, most commonly ornamental (42%) and medicinal (38%). Naturalized taxa tended to have longer residence times and more frequently reported uses than casual ones, suggesting these traits may influence naturalization likelihood. Due to limited systematic sampling across the country, particularly outside the Central Andes, some spatial bias may exist. However, the integration of citizen science-derived data, a methodological innovation in our study, proved to be a promising approach for addressing knowledge gaps and improving detection efforts in regions with limited research capacity. Our findings offer a foundation for advancing the management of biological invasions in Ecuador through early detection, rapid response (EDRR), and species prioritization. Finally, we provide a practical, adaptable and replicable framework, based on citizen science and appropriate statistical analyses, for developing national inventories of non-native plant species in data-deficient countries.
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Environmental
<scp>DNA</scp>
succeeds in detecting a low‐density population of endangered harlequin frogs
(Wiley, 2026-09-11)
Paéz Vacas, Mónica
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Carvajal‐Endara, Sofía
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Baer, Natasha
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Edwards, Christine E.
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Brant, Rachel
The neotropical harlequin frog genus Atelopus is among the most severely impacted by population declines and extinctions. Environmental DNA (eDNA) offers a valuable, non-invasive tool to detect low-density and elusive species. We evaluated its effectiveness in detecting the recently rediscovered, Critically Endangered, Jambato Harlequin Frog (Atelopus ignescens) across seasons and habitats in Angamarca, Ecuador, the species' only known locality, where just 71 individuals (including 6 tadpoles) were recorded after a year of intensive monthly surveys. We collected 18 water samples from 14 sites, including rivers, creeks, and an irrigation ditch used by adults, during both wet and dry seasons. eDNA metabarcoding analysis detected the species in 5 of 18 samples, all from the wet season. Most detections (n = 4) were from rivers, mainly toward the end of the wet season (early May), including three from the only river where tadpoles had been previously observed. The remaining detections came from the least degraded site and the irrigation ditch. Our findings highlight eDNA's value for detecting A. ignescens during reproductive periods and in tadpole habitats. The study underscores the potential of eDNA to inform monitoring and conservation strategies and emphasizes the importance of conserving less disturbed habitats to ensure the survival of critically endangered species. © 2026 The Author(s). Conservation Science and Practice published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.
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Path for recovery: an ecological overview of the Jambato Harlequin Toad (Bufonidae: <i>Atelopus ignescens</i>) in its last known locality, Angamarca Valley, Ecuador
(2024)
Mateo A. Vega-Yánez
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Amanda B. Quezada-Riera
;
Blanca Rios-Touma
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María del Carmen Vizcaíno-Barba
;
William Millingalli
The Jambato Harlequin toad (<jats:italic>Atelopus ignescens</jats:italic>), a formerly abundant species in the Andes of Ecuador, faced a dramatic population decline in the 1980s, with its last recorded sighting in 1988. The species was considered Extinct by the IUCN until 2016, when a fortuitous discovery of one Jambato by a local boy reignited hope. In this study, we present findings from an investigation conducted in the Angamarca parish, focusing on distribution, abundance, habitat preferences, ecology, disease susceptibility, and dietary habits of the species. In one year we identified 71 individuals at different stages of development in various habitats, with a significant presence in agricultural mosaic areas and locations near water sources used for crop irrigation, demonstrating the persistence of the species in a complex landscape, with considerable human intervention. The dietary analysis based on fecal samples indicated a diverse prey selection, primarily comprising arthropods such as Acari, Coleoptera, and ants. Amphibian declines have been associated with diseases and climate change; notably, our study confirmed the presence of the pathogen <jats:italic>Batrachochytrium dendrobatidis</jats:italic> (<jats:italic>Bd</jats:italic>), but, surprisingly, none of the infected Jambatos displayed visible signs of illness. When analyzing climatic patterns, we found that there are climatic differences between historical localities and Angamarca; the temporal analysis also exposes a generalized warming trend. Finally, in collaboration with the local community, we developed a series of management recommendations for terrestrial and aquatic environments occupied by the Jambato.
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Phylogeny of Weinmannia (Cunoniaceae) reveals the contribution of the southern extratropics to tropical Andean biodiversity
(2025)
Ricardo A. Segovia
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Eduardo Aguirre-Mazzi
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Christine E. Edwards
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Alexander G. Linan
;
Alfredo Fuentes
The Andes are a relatively young mountain range with impressive biodiversity, but the biogeographic processes underlying its hyperdiversity are still being unraveled. Novel mid- to high-elevation climates may have served as a biological corridor for the immigration of temperate-adapted lineages to more equatorial latitudes, contributing unknown levels of diversity to this region. We tested the hypothesis that Weinmannia is a lineage of extratropical origin that recently reached and then diversified extensively in the tropical Andes. Using a 2bRAD seq approach to generate a time-calibrated phylogeny for the genus, we found that extratropical species were placed as sister to the rest of Weinmannia and that younger clades were distributed towards more equatorial latitudes. Although Weinmannia exhibited low niche conservatism in elevation and latitude, trait reconstructions of climatic variables showed that the common ancestor of Weinmannia occupied cool climates, with high conservatism of thermal and water availability niche across the phylogeny. Thus, Andean uplift likely created habitats with suitable environmental conditions, providing a dispersal route for extant Weinmannia to colonize the tropical Andes from the southern extratropics. These southern lineages likely converged with those originating in other tropical and extratropical centers of diversification, providing multiple origins for the hyperdiversity in the modern montane forests of the tropical Andes.
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A striking, critically endangered, new species of hillstar (Trochilidae: Oreotrochilus) from the southwestern Andes of Ecuador
(2018)
Sornoza-Molina F.
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Freile J.F.
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Nilsson J.
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Krabbe N.
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Bonaccorso, Elisa
We describe a new species of the genus Oreotrochilus from the southwestern Andes of Ecuador. The new species is most similar in adult male plumage to O. stolzmanni and O. chimborazo. However, male and female show unique combinations of plumage characters that are likely to act as social signals. Phylogenetic analyses based on mitochondrial DNA indicate that this new taxon is closely related to O. stolzmanni and O. melanogaster, whereas genetic distances and preliminary comparisons of vocalizations suggest a sister relationship with O. stolzmanni. The geographic distribution of the new species seems to be restricted to cordillera Chilla-Tioloma-Fierro Urcu, in the southwestern highlands of Ecuador, an area historically poorly explored by ornithologists. Thus, based on its restricted distribution, apparently low population size, and lack of protection of its habitat, we evaluate it as critically endangered. © 2018 American Ornithological Society.
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Applications of geographic information systems and remote sensing techniques to conservation of amphibians in northwestern Ecuador
(2015)
González M.P.
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Bonaccorso E.
;
Papeş M.
The biodiversity of the Andean Chocó in western Ecuador and Colombia is threatened by anthropogenic changes in land cover. The main goal of this study was to contribute to conservation of 12 threatened species of amphibians at a cloud forest site in northwestern Ecuador, by identifying and proposing protection of critical areas. We used Geographic Information Systems (GIS) and remote sensing techniques to quantify land cover changes over 35 years and outline important areas for amphibian conservation. We performed a supervised classification of an IKONOS satellite image from 2011 and two aerial photographs from 1977 and 2000. The 2011 IKONOS satellite image classification was used to delineate areas important for conservation of threatened amphibians within a 200 m buffer around rivers and streams. The overall classification accuracy of the three images was ≥80%. Forest cover was reduced by 17% during the last 34 years. However, only 50% of the study area retained the initial (1977) forest cover, as land was cleared for farming and eventually reforested. Finally, using the 2011 IKONOS satellite image, we delineated areas of potential conservation interest that would benefit the long term survival of threatened amphibian species at the Ecuadorian cloud forest site studied. © 2015 The Authors.
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Systematics of south american snail-eating snakes (Serpentes, dipsadini), with the description of five new species from ecuador and peru
(2018)
Arteaga A.
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Salazar Valenzuela, David
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Mebert K.
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Peñafiel N.
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Aguiar G.
A molecular phylogeny of the Neotropical snail-eating snakes (tribe Dipsadini) is presented including 43 (24 for the first time) of the 77 species, sampled for both nuclear and mitochondrial genes. Morphological and phylogenetic support was found for four new species of Dipsas and one of Sibon, which are described here based on their unique combination of molecular, meristic, and color pattern characteristics. Sibynomorphus is designated as a junior subjective synonym of Dipsas. Dipsas latifrontalis and D. palmeri are resurrected from the synonymy of D. peruana. Dipsas latifasciata is transferred from the synonymy of D. peruana to the synonymy of D. palmeri. A new name, D. jamespetersi, is erected for the taxon currently known as Sibynomorphus petersi. Re-descriptions of D. latifrontalis and D. peruana are presented, as well as the first photographic voucher of an adult specimen of D. latifrontalis, along with photographs of all known Ecuadorian Dipsadini species. The first country record of D. variegata in Ecuador is provided and D. oligozonata removed from the list of Peruvian herpetofauna. With these changes, the number of Dipsadini reported in Ecuador increases to 22, 18 species of Dipsas and four of Sibon. © 2018, Pensoft Publishers. All rights reserved.
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A mouth full of blood – autohaemorrhaging in three Ecuadorian snakes (Squamata: Colubridae & Tropidophiidae)
(2023)
Rödel M.-O.
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Loaiza-Lange A.
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Penner J.
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Neira-Salamea K.D.
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Salazar Valenzuela, David
[No abstract available]
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Upcycling the Banana Industry in Ecuador: A Methodology to Estimate Biowaste and Catalogue of Bioproducts
(2023)
Jiménez M.P.S.
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Tobes, Ibon
Ecuador is the leading exporter of bananas globally. This industry generates a large amount of organic waste since the plant is cut down for every crop, but only the fruit bunch is used. These residues can be converted into sustainable environmental products that could replace polluting materials. This investigation presents a GIS-based methodology used to estimate the biomass of the residues of banana agriculture in Ecuador and to determine how much organic waste could be used as raw materials to manufacture new biodegradable products. We estimated that more than forty million metric tons of waste are produced every nine months. Our methodology can be a low-cost quantitative complement to the survey-based estimations conducted by the Ecuadorian government to evaluate banana production. Additionally, our work presents five products that could be manufactured with organic waste, like disposable plates, bioplastics for food utensils, cardboard covers, fibers for hydraulic cement, and wallpaper. Finally, we offer a product catalog developed as a technical guide for future bio-enterprises to elaborate biodegradable products inspired by a circular economy scheme. In light of the estimated amount of banana waste generated in the country, we consider that Ecuador has the potential to develop an industry based on this raw material to generate products such as those proposed in our review, shifting the banana industry to a more sustainable, profitable process, and generating new incomes and sources of employment. © 2023,. All Rights Reserved.
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Centro de Investigación de la Biodiversidad y Cambio Climático

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