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Vicuñas (Vicugna vicugna) were at risk of extinction due to indiscriminate hunting for their fibre in the mid-twentieth century. The conservation of the species included numerous international and regional legal mechanisms, as well as the will and care of local communities. The vicuña was saved, and now it is classified as "Least concern" by the IUCN Red List of Threatened Species. Sustainable harvest of vicuña fibre is achieved by way of the chaku, capture and live-shearing (an ancient practice, now informed by modern knowledge of biology). Although most communities and cooperatives sell raw fibre, prices are falling. The making of artisanal vicuña garments has been identified as an activity that potentially leads to sustainable development in the Andean Altiplano. This paper analyses a key aspect to achieve this goal, a detailed description of the production (including economic and time costs) involved in weaving a shawl. The manual work has been recognized, with an hourly rate and costs calculated. The first action before starting any intervention was a ceremony, in which the family women infused the fibre with the smoke of a local plant, k'oa (Parastrephia spp.). The rituals and traditions are an important part of livelihoods in the Andes. The steps to creating the finished garment were fibre acquisition, dehairing and cleaning the fibre, spinning, twisting, loom weaving, finishing and fringing. The techniques for spinning and weaving are an essential part of the indigenous cultural heritage; no intervention or suggestion was made in that regard. The final cost of the garment was approximately 3,300 US dollars and half of this cost was the dehairing and cleaning of the fibre. [ABSTRACT FROM AUTHOR]

Steppes and grasslands of semiarid environments in the Central Andes are poorly understood in fossil records due to the lack of modern pollen–vegetation studies. This paper is focused on a systematic analysis of the modern pollen–vegetation relationship in three protected areas of the Puna in Jujuy, northwestern Argentina. Vegetation assemblages were described on the basis of their floristic composition in 32 plots. Different multivariate methods, indices of association and simple linear regression models were applied in order to investigate the degree to which the different vegetation assemblages can be distinguished by their pollen spectra. Five plant assemblages were described, which were partially represented by their pollen spectra: mixed and shrubby steppes, scrubland, grassland with shrubs and high Andean grassland. The pollen spectra reflected both altitudinal variations and environmental conditions. In the Puna belt, at 3600 m, shrubs were present in great abundance and their highest pollen percentages were recorded. Both the abundance of Poaceae herbs and their pollen type increased with increasing altitude up to 4220 m, indicating the transition towards the Altoandean belt. Pollen assemblages evidenced the following environmental conditions: (1) the temperature decrease is characterized by taxa adapted to either cold air (<7 °C) or cold soil (Aridisols-Cryids/Inceptisols-Ustepts type) including Poaceae, Frankenia triandra, Apiaceae, Hoffmansegia glauca, Ephedra, Caryophyllaceae; (2) moisture availability in the soil can be discernible by assemblages indicating dry soil (Aridisols-Durids type), such as Baccharis, Fabiana densa, Maihuniopsis boliviana, Fabaceae, Tetraglochin cristatum and Nassauvia axilaris, from those indicating humid soil (Entisols-Psaments type), such as Parastrephia, Astragalus garbancillo and Gentianaceae. Four taxa exhibited both a good association and a significant correlation and could be considered indicative of the steppe (Baccharis and M. boliviana), scrublands (Parastrephia) and grassland (Poaceae) in a fossil record. This work has important implications for interpreting the dynamics of vegetation during the Holocene in the Puna. [ABSTRACT FROM AUTHOR]

Reference evapotranspiration (ETo) is a variable used to characterize the evaporative demand of the atmosphere and its impact on the water balance. During the last decades, significant ETo variabilities have been observed, especially at mid‐latitudes. These variabilities respond mainly to local variations in their physical drivers, such as solar radiation, vapour pressure deficit or wind speed. In this study, the annual and seasonal ETo estimates are generated using the Penman–Monteith method (FAO). Surface weather stations for the Argentine territory and reanalysis data for southern South America of the last four decades (1981–2020) are used. Contributions of both aerodynamic (ETaero) and radiative (ETrad) effects are evaluated to analyse their driving role. Significant positive ETo trends are observed from reanalysis data throughout Argentina, especially on the central east side of the Andes Mountain range with values up to 10 mm·year−1. Most of these ETo changes respond to positive trends in air temperature in the study area, while those in the central Andes also respond to negative trends in dew point temperatures. On the other hand, the increase in energy availability through positive trends in net surface radiation produced a slightly higher ETo in the northern regions of the country. Regional ETo values have shown to be more sensitive to variations in air temperature in the northeastern areas, although changes in humidity and solar radiation could also play a role. In a context of climate change, given that temperature and rainfall are expected to increase in the central and northeastern region of the country and decrease along the eastern side of the Andes Mountains in the coming decades, the characteristics observed over the 1981–2020 period are expected to intensify in the near future. [ABSTRACT FROM AUTHOR]

The transition to a clean energy future may require a very substantial increase in resources of vanadium. This trend brings into focus the potential health issues related to vanadium in the environment. Most vanadium enters the Earth's crust through volcanic rocks; hence, vanadium levels in groundwaters in volcanic aquifers are higher than in other aquifers and can exceed local guidance limits. The biggest accumulation of volcanogenic sediment on the planet is downwind of the Andes and makes up much of Argentina. Consequently, groundwaters in Argentina have the highest vanadium contents and constitute a global vanadium anomaly. The high vanadium contents have given rise to health concerns. Vanadium could be extracted during remediation of domestic and other groundwater, and although the resultant resource is limited, it would be gained using low‐energy technology. Plain Language Summary: The green energy revolution will greatly increase the demand for vanadium resources, especially for vanadium‐flow batteries. Most vanadium is a by‐product of processing volcanic rocks for other metals. The affinity of vanadium for volcanic rocks is reflected in high vanadium contents in groundwaters in volcanic terrains, in some cases exceeding guidance limits for drinking water. A review of groundwater compositions across Argentina shows values greatly exceeding guidance limits due to a very large eastward flux of vanadium from mineralized volcanic rocks in the Andes. The vanadium could be extracted from groundwaters by developing low‐energy technology. Key Points: Groundwaters in volcanic terrains contain high vanadium contentsVanadium contents are acutely high in Argentina due to inheritance from volcanic rocks in the AndesIncreased demand for vanadium in the green energy revolution highlights the need for awareness of potential contamination of groundwater [ABSTRACT FROM AUTHOR]

A large (>0.1 km 2 ) and complex mass movement in the Central Andes of Argentina (final portion of Cordillera de Olivares, Frontal Cordillera), was studied to identify the triggering factors and understand their relationship with geomorphic, cryogenic and climatic dynamics. This debris-rockslide is composed of clast supported blocks of Permian–Triassic volcanic breccias. In order to characterize this feature, high resolution satellite imagery interpretation was carried out, together with the study of the landslide detachment zones and landslide bodies. These debris-rockslide events could have originated as a consequence of the combination of internal slow deformation and fragmentation under periglacial conditions, followed by a sudden collapse of the rock mass. Pre- and post-slide digital elevation models (DEMs) were created from topographical data with the help of a Geographic Information System (GIS) tool. Approximately 14.89 M m 3 of rock and debris travelled nearly 2 km from an elevation of 5023 m–4325 m asl. Although usually the origin of such catastrophic movements is related to seismically active areas with earthquakes whose magnitude frequently exceed Ms 6, our hypothesis is that this debris-rockslide event has a climatic origin caused by large snow accumulations during winters and subsequent fast meltdown processes during spring, which would have facilitated the sliding. The paper outlines the important role that snowmelt can play in the genesis and evolution of rock displacements and the importance of meteorological data, seismic catalogues, historical aerial photography and satellite images in geomorphological back-analysis. [ABSTRACT FROM AUTHOR]

Central Argentina from the Pampean flat‐slab segment to northern Patagonia (27°–41°S) represents a classic example of a broken retroarc basin with strong tectonic and climatic control on fluvial sediment transport. Combined with previous research focused on coastal sediments, this actualistic provenance study uses framework petrography and heavy‐mineral data to trace multistep dispersal of volcaniclastic detritus first eastwards across central Argentina for up to ca. 1,500 km and next northwards for another 760 km along the Atlantic coast. Although detritus generated in the Andes is largely derived from mesosilicic volcanic rocks of the cordillera, its compositional signatures reflect different tectono‐stratigraphic levels of the orogen uplifted along strike in response to varying subduction geometry as well as different character and crystallization condition of arc magmas through time and space. River sand, thus, changes from feldspatho‐litho‐quartzose or litho‐feldspatho‐quartzose in the north, where sedimentary detritus is more common, to mostly quartzo‐feldspatho‐lithic in the centre and to feldspatho‐lithic in the south, where volcanic detritus is dominant. The transparent‐heavy‐mineral suite changes markedly from amphibole ≫ clinopyroxene > orthopyroxene in the north, to amphibole ≈ clinopyroxene ≈ orthopyroxene in the centre and to orthopyroxene ≥ clinopyroxene ≫ amphibole in the south. In the presently dry climate, fluvial discharge is drastically reduced to the point that even the Desaguadero trunk river has become endorheic and orogenic detritus is dumped in the retroarc basin, reworked by winds and temporarily accumulated in dune fields. During the Quaternary, instead, much larger amounts of water were released by melting of the Cordilleran ice sheet or during pluvial events. The sediment‐laden waters of the Desaguadero and Colorado rivers then rushed from the tract of the Andes with greatest topographic and structural elevation, fostering alluvial fans inland and flowing in much larger valleys than today towards the Atlantic Ocean. Sand and gravel supply to the coast was high enough not only to promote rapid progradation of large deltaic lobes but also to feed a cell of littoral sediment transport extending as far north as the Río de la Plata estuary. [ABSTRACT FROM AUTHOR]

Analyzing the roles of ecology and geography on speciation and lineage diversification can shed light on the processes that generate and maintain biodiversity. Additionally, lineages rapidly diversifying across unstable habitats provide substantial challenges for resolving evolutionary histories and delimiting species. Physaria is represented in South American by six species distributed from southern Bolivia to northern central Argentina and growing in highlands of the southern-central Andes, but also along the hills and lowlands of central-eastern Argentina. This biogeographical variability, not common among other South American crucifers (Brassicaceae), prompted us to conduct different climatic niche and geographical range comparisons to study the potential roles of ecology and geography through the diversification of the group. However, the remarkable similarity between these species, coupled with the continuous variability of the diagnostic morphological characters, blurs the species boundaries. Therefore, in order to identify independent evolving lineages, we first employed species delimitation methods together with the general lineage concept of species, and used molecular sequences from nuclear ribosomal and chloroplast loci. Secondly, and in the light of the lineages obtained, we explored the roles of geography and ecology on the diversification of South American Physaria and tested for presence of phylogenetic niche-conservatism or niche-divergence patterns, as well as potential ecological speciation. Lineages identified by these delimitation methods were highly congruent with described species; nevertheless, some morphospecies were included under the same independent evolutionary lineage. Our results suggest that the climatic niche divergence along the heterogeneous landscape apparently was a major factor promoting diversification of the South American Physaria. Divergence was registered mainly on the temperature dimension, which promoted shifts between cold-temperate habitats associated with the highlands of the central-southern Andes and warm lowlands from central-eastern Argentina, i.e., the Monte and Dry Chaco ecoregions. In addition, some degree of niche divergence along the precipitation gradient was also secondarily recovered. Allopatry and dispersal capabilities also seem to be associated with the diversification of the group, presumably through the Late Pliocene-Pleistocene, and promoted by glacial cycles and climatic oscillations during the Quaternary. Results of these analyses are also discussed in a general context, which will contribute to the understanding of the evolutionary and ecological patterns of South American Brassicaceae. [ABSTRACT FROM AUTHOR]