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Austral Yungas cloud forest (Southern Bolivia and NW Argentina) is known for its high diversity, steep landscape and low accessibility. Anacroneuria Klapálek (Plecoptera: Perlidae) species in this ecoregion have been seldom studied. We aim to know its species diversity (based on adult characters) and explore larval characters important for their recognition. We have reared dozens of larvae from different localities and collected adults with light traps. Reared adults and associated larval exuviae were studied, photographed and drawn. We have identified 13 species (based on male aedeagus) and successfully associated larval and adult stages for seven species. In the present paper we describe seven new species: Anacroneuria tafi sp. nov., A. flavinigra sp. nov., A. saican sp. nov., A. triplex sp. nov., A. calilegua sp. nov., A. lutea sp. nov., and A. tupacamaru sp. nov. For six species previously described we present new data and stage descriptions: A. arrazayalensis Orce, A. handlirschi Klapálek, A. reedi (Navás), A. tucuman Stark, A. saltensis Froehlich, and A. chimborazo Stark. Genetic divergence for some of these species was studied using the barcode region of the mitochondrial gene COI. A key to the male adults of all the species of Anacroneuria from Northwestern Argentina is presented. [ABSTRACT FROM AUTHOR]

In mountain environments, both temperature and food availability vary strongly with altitude, leading to a major challenge to the thermo‐energetic balance of organisms. In this sense, the behavioral repertoire is crucial for animals' adequacy because it implies a short‐term response in the face of environmental changes. In this paper, we explored the behavioral versatility of Phyllotis vaccarum and Abrothrix andina (Rodentia: Cricetidae), two of the mammal species with the highest altitudinal distribution worldwide. By radiotelemetry, we analyzed the activity pattern, home range, and microhabitat selection in populations of both species inhabiting at 2300 and 3100 m altitude in the Central Andes of Argentina. We found that A. andina was diurnal at 3100 m and cathemeral at 2300 m a.s.l., while P. vaccarum was nocturnal at both elevations. Moreover, home range size was larger in A. andina males at 3100 m in contrast to females at identical altitude and males at 2300 m; while, in P. vaccarum, there were no differences according to altitude or sex. Furthermore, we recorded a complex and species‐specific microhabitat selection pattern at different altitudes. Finally, the magnitude of behavioral variability was higher in A. andina than in P. vaccarum for all the traits analyzed. These results are discussed with emphasis on the impact of behavioral traits and their plasticity for species adequacy in high‐altitude environments. [ABSTRACT FROM AUTHOR]

Some of the most intense thunderstorms in the world take place in central and northern Argentina, and their start and development is strongly influenced by the orography of the Andes and sierras de Coórdoba. These thunderstorms are associated with the occurrence of severe weather phenomena that generate important material damages and economic loss in rural and urban areas. The aim of this paper was to do the observational study of the spatial and temporal distribution of different severe weather phenomena, in particular, hail, intense rain and strong winds with gusts. Most of these events took place between the evening and midnight, and also between late Spring and early Summer. At the same time, while studying the occurrence of hail, it was found that its density of accumulation decreased as its diameter increased. [ABSTRACT FROM AUTHOR]

With ongoing climate change, there is a pressing need to better understand how much water is stored as ground ice in areas with extensive permafrost occurrence, as well as how the regional water balance may alter in response to the potential generation of meltwater from permafrost degradation. However, field-based data on permafrost in remote and mountainous areas such as the South American Andes are scarce. Most current ground ice estimates are based on broadly generalized assumptions such as volume–area scaling and mean ground ice content estimates of rock glaciers. In addition, ground ice contents in permafrost areas outside of rock glaciers are usually not considered, resulting in a significant uncertainty regarding the volume of ground ice in the Andes and its hydrological role. In Part 1 of this contribution, present an extensive geophysical data set based on electrical resistivity tomography and refraction seismic tomography surveys to detect and quantify ground ice of different landforms and surface types in several study regions in the semi-arid Andes of Chile and Argentina with the aim to contribute to the reduction of this data scarcity. In Part 2 we focus on the development of a strategy for the upscaling of geophysics-based ground ice quantification to an entire catchment to estimate the total ground ice volume (and its approximate water equivalent) in the study areas. In addition to the geophysical data, the upscaling approach is based on a permafrost distribution model and classifications of surface and landform types. In this paper, we introduce our upscaling strategy, and we demonstrate that the estimation of large-scale ground ice volumes can be improved by including (i) non-rock-glacier permafrost occurrences and (ii) field evidence through a large number of geophysical surveys and ground truthing information. The results of our study indicate that (i) conventional ground ice estimates for rock-glacier-dominated catchments without in situ data may significantly overestimate ground ice contents and (ii) substantial volumes of ground ice may also be present in catchments where rock glaciers are lacking. [ABSTRACT FROM AUTHOR]

In this paper we review the growing evidence of anthropogenic landscapespresent in the semi-deciduous neotropical forest biomes of eastern NW Argentina,which have remained relatively neglected in favour of arid to semi-arid western Andean regions. The evidence gathered in de El Alto-Ancasti provides animportant case study where multidisciplinary methodologies have beenapplied to sites that document the emergence and variability in food productionstrategies across the eastern Andean forests and grasslands of NWArgentina. We discuss evidence offarming structures from archaeological surveys, plant management from phy-tolith analysis, and the tempo and nature of settlement from archaeological excavations undertaken at a variety of sites in the El Alto Ancasti mountainrange. We suggest that the communities that inhabited this region during thefirst millennium AD (ca. 1500–1000 BP) established a strategy of 'overlappingpatchworks' of food production that were able to contend with considerableseasonal variability. We argue that, through the use of cross-channelling, low river areas, erosion control techniques and the establishment of mesothermal crops,including maize, legumes, and tubers, throughout the region, these societies adopted flexible strategies to adapt to life in a region prone to climatic change [ABSTRACT FROM AUTHOR]