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Atmospheric pollution and accelerated environmental deterioration for the increasing use of fossil fuels have directed research in the energy field towards the search for alternative, renewable, efficient and, above all, more environmentally friendly sources. Among the raw materials that are of great interest in the generation of biofuels are lignocellulosic residues, which are currently produced in abundant quantities, either by the simple action of nature or because they are part of the agro-industrial chain of a given region. For this reason in the present work, the biomass of Eucalyptus globulus was evaluated as a low-cost and widely available source for obtaining liquid biofuel, for which a preliminary physical and chemical characterization was carried out, by considering established standard specifications. Thermochemical conversion tests were carried out by pyrolysis in an N2 atmosphere and through the application of a factorial experimental design (22) contemplating the influence of experimental variables such as residence time and temperature, it was possible to obtain at 550 ºC and during 20 min of reaction, a bio-oil with a maximum yield of 45,2 % and whose physical and chemical properties are within the range estimated in the literature for biofuels of lignocellulosic origin, such as the calorific value (16,7 MJ/kg). Therefore, the biomass of Eucalyptus globulus can be considered as a raw material with potential to be explored in the generation of energy., La contaminación atmosférica y el acelerado deterioro ambiental por el creciente uso de combustibles fósiles, ha direccionado las investigaciones en el campo energético hacía la búsqueda de fuentes alternativas, renovables, eficientes y sobre todo más amigables con el medio ambiente. Entre la materia prima que cobra gran interés en la generación de biocombustibles, se encuentran los residuos lignocelulósicos que actualmente se producen en abundantes cantidades, ya sea por simple acción de la naturaleza o porque hacen parte de la cadena agroindustrial de una región dada. Es por ello que en el presente trabajo se evaluó la biomasa de Eucalyptus globulus, como fuente de bajo costo y amplia disponibilidad en la obtención de biocombustible líquido, para lo cual se llevó a cabo una caracterización física y química preliminar teniendo en cuenta especificaciones establecidas en normatividad del sector. Se realizaron ensayos de conversión termoquímica por medio de una pirólisis en atmósfera de N2 y a través de la aplicación de un diseño experimental factorial (22) contemplando la influencia de variables experimentales tales como tiempo de residencia y temperatura, fue posible obtener a 550 ºC y durante 20 min de reacción, un bioaceite con un rendimiento máximo del 45,2 % y cuyas propiedades físicas y químicas se encuentran dentro del rango estimado en literatura para biocombustibles de origen lignocelulósico, tal es el caso del poder calorífico (16,7 MJ/kg). Por lo tanto, la biomasa de Eucalyptus globulus puede ser considerada como materia prima con potencial a ser explorado en la generación de energéticos.

Incomplete species inventories for Antarctica represent a key challenge for comprehensive ecological research and conservation in the region. Additionally, data required to understand population dynamics, rates of evolution, spatial ranges, functional traits, physiological tolerances and species interactions, all of which are fundamental to disentangle the different functional elements of Antarctic biodiversity, are mostly missing. However, much of the fauna, flora and microbiota in the emerged ice-free land of the continent have an uncertain presence and/or unresolved status, with entire biodiversity compendia of prokaryotic groups (e.g. bacteria) being missing. All the available biodiversity information requires consolidation, cross-validation, re-assessment and steady systematic inclusion in order to create a robust catalogue of biodiversity for the continent.

Microsatellite data, DNA sequences and their corresponding GenBank Accession nos. are deposited in the CSIC institutional repository (http://digital.csic.es/handle/10261/85523). Geographical coordinates of the locations used to model the ecological niche of the trumpeter finch from its current range are provided in Table S4 (Supporting Information) and the R-script for running the ecological niche models are available in GitHub (https://github.com/SaraVarela/Bucanetes)., Phylogeographical studies are common in boreal and temperate species from the Palaearctic, but scarce in arid-adapted species. We used nuclear and mitochondrial markers to investigate phylogeography and to estimate chronology of colonization events of the trumpeter finch Bucanetes githagineus, an arid-adapted bird. We used 271 samples from 16 populations, most of which were fresh samples but including some museum specimens. Microsatellite data showed no clear grouping according to the sampling locations. Microsatellite and mitochondrial data showed the clearest differentiation between Maghreb and Canary Islands and between Maghreb and Western Sahara. Mitochondrial data suggest differentiation between different Maghreb populations and among Maghreb and Near East populations, between Iberian Peninsula and Canary Islands, as well as between Western Sahara and Maghreb. Our coalescence analyses indicate that the trumpeter finch colonized North Africa during the humid Marine Isotope Stage 5 (MIS5) period of the Sahara region 125 000 years ago. We constructed an ecological niche model (ENM) to estimate the geographical distribution of climatically suitable habitats for the trumpeter finch. We tested whether changes in the species range in relation to glacial–interglacial cycles could be responsible for observed patterns of genetic diversity and structure. Modelling results matched with those from genetic data as the species' potential range increases in interglacial scenarios (in the present climatic scenario and during MIS5) and decreases in glacial climates (during the last glacial maximum, LGM, 21 000 years ago). Our results suggest that the trumpeter finch responded to Pleistocene climatic changes by expanding and contracting its range., Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

We compiled, completed and revised eukaryotic species inventories present in terrestrial and freshwater ecosystems in Antarctica. This includes the first account for many groups of eukaryotic microorganisms. We also introduce a first catalogue of amplicon sequence variants (ASVs) of the prokaryote biodiversity. Available listings to data were searched, integrated, taxonomically harmonized and curated by experts to create comprehensive checklists of Antarctic organisms

Advice from avian influenza experts suggests that there is a high risk that highly pathogenic avian influenza will arrive in the Southern Ocean during the austral summers.

A pesar del aislamiento y la lejanía del resto de continentes y las principales zonas de actividad humana, el continente antártico no es ajeno a las amenazas que para su conservación provienen del impacto humano. El cambio climático, la contaminación, la sobrepesca, la introducción de especies invasoras y efectos directos sobre el hábitat son algunos de los factores que se ciernen sobre el ecosistema antártico y su biodiversidad. Los pingüinos son los vertebrados mas abundantes y están ampliamente distribuidos en la Antártida y considerando su posición en la parte alta de la cadena trófica hace de este grupo un excelente bioindicador de la salud de este ecosistema. No tenemos mas que escucharles y prestarles atención para conocer cuales son los problemas de conservación a los que se enfrenta esta región.

Within the Southern Ocean, the greatest warming is occurring on the Antarctic Peninsula (AP) where clear cryospheric and biological consequences are being observed. Antarctic coastal systems harbour a high diversity of marine and terrestrial ecosystems heavily influenced by Antarctic seaweeds (benthonic macroalgae) and bird colonies (mainly penguins). Primary sea spray aerosols (SSA) formed by the outburst of bubbles via the sea-surface microlayer depend on the organic composition of the sea water surface. In order to gain insight into the influence of ocean biology and bio-geochemistry on atmospheric aerosol, we performed in situ laboratory aerosol bubble chamber experiments to study the effect of different leachates of biogenic material - obtained from common Antarctic seaweeds as well as penguin guano - on primary SSA. The addition of different leachate materials on a seawater sample showed a dichotomous effect depending on the leachate material added - either suppressing (up to 52%) or enhancing (22–88%) aerosol particle production. We found high ice nucleating particle number concentrations resulting from addition of guano leachate material. Given the evolution of upper marine polar coastal ecosystems in the AP, further studies on ocean-atmosphere coupling are needed in order to represent the currently poorly understood climate feedback processes.

Visitor Site Guidelines are the principal instruments guiding tourist activities and behaviour at intensively visited sites. These instruments attempt to minimize tourist impacts on Antarctic wildlife, including penguins. However, some recommendations still need to be reinforced by empirical research. Although penguins have enjoyed considerable research attention, a knowledge gap still exists regarding penguins' behavioural responses to realistic tourist activities, including talking sound, viewing distance and movement speed. To fill this gap, we conducted a series of experiments to simulate these activities on two penguin species breeding at an intensively visited site during the 2019–2020 season. We performed 106 replicates of passive and active human presence treatments. Responses varied between species, but active human presence consistently triggered significantly higher responses of strong vigilance behaviour. Our results reinforce Visitor Site Guidelines' recommendations of keeping quiet, moving slowly and increasing viewing distance if changes in behaviour are observed. We also recommend adopting a more conservative viewing distance in the early breeding season. Additional management-orientated empirical studies are needed, including on different species, sites and stages of the breeding season, as such results are valuable for strengthening tourism guidelines and assessing the efficacy of management measures under a post-COVID-19 scenario of increasing Antarctic tourism.