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Viscous-flow features in perennially frozen talus/debris called rock glaciers are being systematically inventoried as part of the global climate-related monitoring of mountain permafrost. In order to avoid duplication and confusion, guidelines were developed by the International Permafrost Association to discriminate between the permafrost-related landform "rock glacier" and the glacier-related landform "debris-covered glacier". In two regions covered by detailed field measurements, the corresponding data- and physics-based concepts are tested and shown to be adequate. Key physical aspects which cause the striking morphological and dynamic differences between the two phenomena/landforms concern the following: tight mechanical coupling of the surface material to the frozen rock–ice mixture in the case of rock glaciers, contrasting with essential non-coupling of debris to the glaciers they cover; talus-type advancing fronts of rock glaciers exposing fresh debris material from inside the moving frozen bodies, as opposed to massive surface ice exposed by increasingly rare advancing fronts of debris-covered glaciers; and increasing creep rates and continued advance of rock glaciers as convex landforms with structured surfaces versus predominant slowing down and disintegration of debris-covered glaciers as often concave landforms with primarily chaotic surface structure. Where debris-covered surface ice is or has recently been in contact with thermally controlled subsurface ice in permafrost, complex conditions and interactions can develop morphologies beyond simple either–or-type landform classification. In such cases, the remains of buried surface ice mostly tend to be smaller than the lower size limit of "glaciers" as the term is applied in glacier inventories and to be far thinner than the permafrost in which they are embedded. [ABSTRACT FROM AUTHOR]

We studied the dynamics of methane (CH4) and carbon dioxide (CO2) in a eutrophic tropical reservoir located in the Colombian Andes. Temporal and spatial dynamics were addressed through sampling during six field campaigns conducted throughout a two-year period. We monitored fluxes at the air-water interface, dissolved gas concentrations, physical and chemical properties of the water column, microstructure profiles of turbulence, and meteorological conditions. Throughout the study period, the reservoir was a persistent source of CH4 to the atmosphere with higher emissions occurring in the near inflow region. During periods of low water levels, both the emissions and surface concentrations of CH4 were higher and more spatially heterogeneous. The measured CO2 fluxes at the air-water interface changed direction depending on the time and location, showing alternating uptake and emissions by the water surface. Mass balances of dissolved CH4 in the surface mixed layer revealed that biochemical reactions and gas evasion were the most significant processes influencing the dynamics of dissolved CH4, and provided new evidence of possible oxic methane production. Our results also suggest that surface CH4 concentrations are higher under more eutrophic conditions, which varied both spatially and temporally. [ABSTRACT FROM AUTHOR]

Quantitative isotopic paleoaltimetry has been applied in regions where Rayleigh distillation controls isotopic lapse rates. Air mass mixing and moisture recycling are viewed as complicating factors. We show here that, because of such effects, a cross‐Andean transect of meteoric water δD values precisely marks the geographic position of the Western Cordillera crest. This modern water signal is also recorded in Pliocene‐Pleistocene hydrated volcanic glass δD values. δD values between the Pacific coast and Western Cordillera exhibit no trend up to 2.5 km elevation and 100 km inboard, consistent with an arid climate in which Amazonian moisture is topographically blocked and Pacific moisture is efficiently recycled. The result is a large δD lapse rate (−98‰/km) and an abrupt horizontal δD shift (2‰/km) at the Western Cordillera crest. Therefore, we conclude that cross‐orogen δD transects could locate the ancient Western Cordillera crest. Plain Language Summary: Mountains have an outsized control on climate. Moist air masses rise and cool to cross high elevations, resulting in enhanced precipitation on the windward side and dry conditions downwind These processes influence the isotopic compositions of rainfall and of materials preserved in the geologic record that form from the interaction of rain with near‐surface materials. Here we report data from transects across the Peruvian Central Andes and show that the isotopic compositions shift abruptly at the position of highest topography (the crest of the Western Cordillera). This suggest that isotopic compositions of materials preserved in the geologic record might help establish the geographic position of the crests of mountain belts in the past. Key Points: There is a substantial shift in the hydrogen isotope ratios of meteoric water at the Andean Western Cordillera crestVolcanic glass younger than 5 million years old shows similar ratio distributions to modern soil and precipitation water valuesVolcanic arc migration over time can be identified with meteoric water stable isotope records [ABSTRACT FROM AUTHOR]

This integrated pedo-geoarchaeological study focuses on three abandoned prehispanic terrace agricultural systems near Laramate in the southern Andes of Peru, aiming to unravel the pedological and land-use history of the region. The investigation involved contextualizing the former agricultural management system within its paleoecological framework and assessing the impact of agricultural practices on soil development and quality. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological settings, provided an ideal setting for the investigation. Comparative analyses between non-irrigated agricultural terrace soils and undisturbed reference sequences were conducted, employing a range of methodologies, including surveys, soil analysis, GIS and remote sensing, palaeobotany, and radiocarbon dating. The study identifies three WRB Reference Soil Groups in the Laramate region: Phaeozems , Andosols , and Anthrosols. Unique characteristics of Phaeozems challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. Despite long-term use, terrace soils (Anthrosols) show no severe degradation, maintaining balanced acidity and nutrient availability for successful crop cultivation. Tillage horizons of all terrace soils exhibit elevated organic matter content, highlighting the sustainability of prehispanic agricultural practices through a consistent application of organic manure. Phytolith concentrations indicate extensive agricultural activities, particularly maize cultivation, with varying patterns suggesting changes in cultivation or fertilization practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Notably, the abandonment of the prehispanic cultivation system was not linked to soil exhaustion or terrace instability. The prehispanic history of terraced agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and agricultural factors. The initial phase, from the Formative Paracas period to the Early Nasca period (800 BCE–200 CE), witnessed the establishment of agricultural terraces with simple terrace architecture, while the Middle Horizon (600–1000 CE) saw systematic areal expansion influenced by the Wari culture. Adaptations to drier conditions included terraced agriculture on volcanic soils. The Late Intermediate Period (1000–1450 CE) witnessed hydrological variability and further terrace expansion to lower altitudes and less agriculturally suitable locations. The final phase, marked by the onset of the Hispanic colonial period in 1532 CE, saw the gradual abandonment of terraced agricultural systems due to demographic shifts and reorganization of production systems. Despite this, the historical trajectory underscores the adaptability and resilience of prehispanic communities in the Laramate region, showcasing innovative terrace agriculture as a means of coping with changing environmental conditions across diverse landscape units. [ABSTRACT FROM AUTHOR]

The chemical composition of PM 10 and non-overlapping PM 2.5 was studied at the summit of Mt. Chacaltaya (5380 m a.s.l., lat. - 16.346950°, long. - 68.128250°) providing a unique long-term record spanning from December 2011 to March 2020. The chemical composition of aerosol at the Chacaltaya Global Atmosphere Watch (GAW) site is representative of the regional background, seasonally affected by biomass burning practices and by nearby anthropogenic emissions from the metropolitan area of La Paz–El Alto. Concentration levels are clearly influenced by seasons with minima occurring during the wet season (December to March) and maxima occurring during the dry and transition seasons (April to November). Ions, total carbon (EC + OC), and saccharide interquartile ranges for concentrations are 558–1785, 384–1120, and 4.3–25.5 ng m -3 for bulk PM 10 and 917–2308, 519–1175, and 3.9–24.1 ng m -3 for PM 2.5 , respectively, with most of the aerosol seemingly present in the PM 2.5 fraction. Such concentrations are overall lower compared to other high-altitude stations around the globe but higher than Amazonian remote sites (except for OC). For PM 10 , there is dominance of insoluble mineral matter (33 %–56 % of the mass), organic matter (7 %–34 %), and secondary inorganic aerosol (15 %–26 %). Chemical composition profiles were identified for different origins: EC, NO 3- , NH 4+ , glucose, and C 2 O 42- for the nearby urban and rural areas; OC, EC, NO 3- , K + , acetate, formate, levoglucosan, and some F - and Br - for biomass burning; MeSO 3- , Na + , Mg 2+ , K + , and Ca 2+ for aged marine emissions from the Pacific Ocean; arabitol, mannitol, and glucose for biogenic emissions; Na + , Ca 2+ , Mg 2+ , and K + for soil dust; and SO 42- , F - , and some Cl - for volcanism. Regional biomass burning practices influence the soluble fraction of the aerosol between June and November. The organic fraction is present all year round and has both anthropogenic (biomass burning and other combustion sources) and natural (primary and secondary biogenic emissions) origins, with the OC/EC mass ratio being practically constant all year round (10.5 ± 5.7, IQR 8.1–13.3). Peruvian volcanism has dominated the SO 42- concentration since 2014, though it presents strong temporal variability due to the intermittence of the sources and seasonal changes in the transport patterns. These measurements represent some of the first long-term observations of aerosol chemical composition at a continental high-altitude site in the tropical Southern Hemisphere. [ABSTRACT FROM AUTHOR]

The high-Andean grasslands of Peru provide a wide range of goods and services, not only locally, but also regionally and globally. However, land-use change and global warming are threatening these ecosystems, of which soil organic carbon (SOC) is a key element affecting their sustainability. In this study, we have analyzed the variation of SOC stocks to a depth of 20 cm in 16 paired cropland and grassland sites located in the Sullccapallcca stream micro-watershed (elevation > 3600 m.a.s.l., Ayacucho, Peru). We have also analyzed the environmental controls on the SOC stocks and their variation with land-use change. We found that the studied high-Andean grasslands store high SOC contents (247 Tn SOC ha−1), whose spatial variability was partially explained by the slope of the terrain (r2 = 0.26, p < 0.05). Despite the higher NDVI, the conversion of these grasslands into croplands decreased the SOC stock by 39 Tn SOC ha−1 on average, a decrease that was more pronounced when the initial SOC content of the grassland was higher (r2 = 0.60, p < 0.05). This study provides the first evidence of the effects of land-use change on the SOC in the region, although the mechanisms involved still need to be investigated. [ABSTRACT FROM AUTHOR]

Reference conditions are difficult to find in the Anthropocene but essential for effective biodiversity conservation. Aquatic ecosystems in the Andes‐Amazon transition zone of Colombia are now at high risk due to expanded human activities after peace agreements in 2016 ended armed conflict because lands formerly controlled by FARC and other armed groups are now prone to agricultural and urban expansion. Particularly, expanding human land use may reduce fish diversity across the altitudinal gradient, especially in the premontane streams (i.e., <500 m a.s.l.) because lands are more amenable to human use than at greater altitudes. We evaluated fish α‐diversity (measured as species richness, total abundance, and effective species number) and β‐diversity (spatial and temporal) in 12 sites over 8 years bracketing the end of armed conflict. All α‐diversity and β‐diversity analyses were evaluated relative to categorical altitude (< or >500 m) and continuous altitude. Strong differences in fish community structure among sites occurred as a function of altitude. Fish communities exhibit altitudinal biodiversity gradients that are consistent in space and time, and that need to be accounted for conservation and management considerations. Our results provide a reference to identify short‐ and long‐term changes due to impending human land use at a critical moment for the conservation of tropical fish diversity. Similar studies in other areas of the upper Amazon Basin are needed to evaluate effects of subsequent human activities on diversity patterns and our study area to compare to reference conditions reported here. [ABSTRACT FROM AUTHOR]

Common distributional patterns have provided the foundations of our knowledge of Neotropical biogeography. A distinctive pattern is the "circum‐Amazonian distribution", which surrounds Amazonia across the forested lowlands south and east of the basin, the Andean foothills, the Venezuelan Coastal Range, and the Tepuis. The underlying evolutionary and biogeographical mechanisms responsible for this widespread pattern of avian distribution have yet to be elucidated. Here, we test the effects of biogeographical barriers in four species in the passerine family Thamnophilidae by performing comparative demographic analyses of genome‐scale data. Specifically, we used flanking regions of ultraconserved regions to estimate population historical parameters and genealogical trees and tested demographic models reflecting contrasting biogeographical scenarios explaining the circum‐Amazonian distribution. We found that taxa with circum‐Amazonian distribution have at least two main phylogeographical clusters: (1) Andes, often extending into Central America and the Tepuis; and (2) the remaining of their distribution. These clusters are connected through corridors along the Chaco–Cerrado and southeastern Amazonia, allowing gene flow between Andean and eastern South American populations. Demographic histories are consistent with Pleistocene climatic fluctuations having a strong influence on the diversification history of circum‐Amazonian taxa, Refugia played a crucial role, enabling both phenotypic and genetic differentiation, yet maintaining substantial interconnectedness to keep considerable levels of gene flow during different dry/cool and warm/humid periods. Additionally, steep environmental gradients appear to play a critical role in maintaining both genetic and phenotypic structure. [ABSTRACT FROM AUTHOR]

Colonial control is studied through a narrative sound designed to entomb a black woman's voice under noise. Interpreting Charles Marie de La Condamine's 1746 letter, recounting the murder of a colleague during his scientific travels through Cuenca, involves mapping the effort to quell the scandalous scream of an enslaved woman who spoke up against the traveller and went unpunished. The text is read for the concatenation of sounds that follow her scream and the way these accrue into white, order-restoring noise at the hands of the author. However, simultaneously tracking how this defiant sound travels and is inscribed through layers of noise underscores the limits of such attempts to erase a racialised voice. Examining this tangential episode in an Andean town within La Condamine's larger Geodesic Mission (1735–45) introduces narrative silencing to the study of noise-making, wherein race thwarts the act of writing to regulate sounds during colonial encounters. [ABSTRACT FROM AUTHOR]

Imaginaries arerepresentational assemblages of the past, ways to understand and(re)create history and projections of the self and others that ground ever-changing identities. They are embedded in the cultural meaning-making systems of each society. However, researchers and practitioners within the heritage field have not directly analysed heritage as a product-producer of imaginaries or conceived heritage itself as an imaginary. This conceptual article proposes imaginaries as a useful analytical lens to critically study heritage. Imaginariesenable us to uncover how people assume and signify heritage from various positions and experiences. Furthermore, this article aims to shed light on how alternative imaginaries grounded in non-western ontologies enable us to rethink heritage meaning and practice in the encounters and conflicts between different systems of meaning in daily life. More concretely, we identify three significant contributions of using imaginaries as a lens for the study of heritage. To illustrate our theoretical propositions, we incorporate empirical examples from ethnographic fieldwork conducted in the Ecuadorian Andes. [ABSTRACT FROM AUTHOR]

Francisco Pulgar-Vidal (1929-2012) was a Peruvian composer, pianist and music educator. Born in Huánuco, surrounded by Andes Mountains and the Amazonian jungle, Pulgar-Vidal was exposed to Western music and instruments at a young age. He took violin, piano and bassoon lessons and later took harmony and composition classes. He received a doctorate in music at the Lima National Conservatory. Pulgar-Vidal's music integrates folklores and distinctive Peruvian rhythms with compositional techniques, trendy in the 1950s. As an influential figure in Peruvian music history, he was awarded many prizes, including the Dunker Lavalle Prize and the Kuntur National Folklore Prize. He is widely known in Peru, but his fame has not spread far beyond the borders of his native country. This paper aims to introduce him and his solo piano works to a broader audience. While the term "avant-garde" may be a red flag to some, Pulgar-Vidal's compositional style is very approachable. His solo piano works serve as an excellent repertoire for intermediate and advanced pianists interested in Latin American culture. This research paper begins with contextual information about Peruvian and Latin-American music prior to Pulgar-Vidal's time, including a list of musical features in Peruvian traditional music. It follows a brief biography of Pulgar-Vidal. The last chapter demonstrates how he incorporated the Peruvian musical elements with the European compositional techniques in his solo piano works and discusses the suitability of the selected works for intermediate and advanced students. [ABSTRACT FROM AUTHOR]

Mining activities in cold regions are vulnerable to snow avalanches. Unlike operational facilities, which can be constructed in secure locations outside the reach of avalanches, access roads are often susceptible to being cut, leading to mine closures and significant financial losses. In this paper we discuss the application of avalanche runout modelling to predict the operational risk to mining roads, a long-standing problem for mines in high-altitude, snowy regions. We study the 35 km long road located in the "Cajón del rio Blanco" valley in the central Andes, which is operated by the Codelco Andina copper mine. In winter and early spring, this road is threatened by over 100 avalanche paths. If the release and snow cover conditions can be accurately specified, we find that avalanche dynamics modelling is able to represent runout, and safe traffic zones can be identified. We apply a detailed, physics-based snow cover model to calculate snow temperature, density and moisture content in three-dimensional terrain. This information is used to determine the initial and boundary conditions of the avalanche dynamics model. Of particular importance is the assessment of the current snow conditions along the avalanche tracks, which define the mass and thermal energy entrainment rates and therefore the possibility of avalanche growth and long runout distances. [ABSTRACT FROM AUTHOR]

A faunal overview is presented of the molluscan families Amphibulimidae, Megaspiridae, Odontostomidae, Orthalicidae, Simpulopsidae in Bolivia, Ecuador, and Peru. These Central Andean countries are known for their biodiverse malacofauna, of which the superfamily Orthalicoidea takes relatively a large share. In this paper the five families containing 103 (sub)species, for which systematic information (original publication, type locality, type depository, summarizing literature) and distributional records are presented. All species are illustrated by photographs of the type material or, if this could not be located, by a reproduction of the original figure. The following new taxon is introduced: Thaumastus (Thaumastus) sumaqwayqu sp. n. Junior subjective synonyms are established for: Plekocheilus (Sparnotion) Pilsbry, 1944 = Plekocheilus (Eudolichotis) Pilsbry, 1896; Scholvienia (Thomsenia) Strebel, 1910 = Scholvienia Strebel, 1910; Sultana (Trachyorthalicus) Strebel, 1909 = Sultana (Metorthalicus) Pilsbry, 1899; Plekocheilus (Eurytus) conspicuus Pilsbry, 1932 = Thaumastus (Thaumastus) hartwegi (Pfeiffer in Philippi, 1846); Zebra gruneri Strebel, 1909 = Orthalicus maracaibensis (Pfeiffer, 1856); Scholvienia jaspidea minor Strebel, 1910 = Scholvienia alutacea (Reeve, 1850); Bulimus bifasciatus unicolor Philippi, 1869 = Scholvienia brephoides (d'Orbigny, 1835). A new status is given to Plekocheilus mcgintyi 'Pilsbry' H.B. Baker, 1963 (subspecies of Bulinus piperitus Sowerby I, 1837); Strophocheilus superstriatus var. prodeflexus Pilsbry, 1895 (subspecies of Bulinus piperitus Sowerby I, 1837); Thaumastus (Quechua) salteri maximus Weyrauch, 1967 (subspecies of Thaumastus (Quechua) olmosensis Zilch, 1954); Pseudoglandina agitata Weyrauch, 1967 (nomen inquirendum). New combinations are: Clathrorthalicus corydon (Crosse, 1869), and Cyclodontina chuquisacana (Marshall, 1930). Lectotypes are now designated for Bulimus incisus Hupé, 1857 and Bulinus piperitus Sowerby I, 1837. [ABSTRACT FROM AUTHOR]

This paper analyzes the trajectory of two indigenous communities from Neuquen through one century, focusing on the paths followed to access and remain in their territories, as well as the highs and lows in relation to their persistence as mapuche communities. The main goal was to explain how they achieved their current state of community reconstitution, and their relationship with politics at a provincial level, specifically in the context of the development of a new political line within the Confederación Mapuche de Neuquén at the beginning of this century. The article studied the factors that, from the genocide to the native peoples on, conditioned their possibilities of staying cohesive in a context of struggle with dominant territorialities: public policies on access to land, designed by the National State first, and then by the province, the actions of different agents in office, the mapuche political praxis and the bond they established with their supracommunal organizations. The heterogeneity of situations in the space of Neuquen led to define two cases to develop the analysis: Paicil Antriao, in the southern Andes area, and Campo Maripe, in the central eastern plateau zone. [ABSTRACT FROM AUTHOR]

This paper evaluates the anaerobic digestion of agricultural waste, manure and slaughterhouse residues of species typical of the Andes, such as llama, vicuña and guinea pig; quinoa, amaranth and wheat straw in order to be able to use them as a renewable energy source and boost rural development in the region. Has been used sludge from a WWTP as inoculum, evaluating the effect of two relationships between the substrate and inoculum (RSI) for both livestock and agricultural waste. The highest cumulative maximum methane production rate was obtained for the residues of flame manure and quinoa straw for an RSI of 1:2 with productions of 376.08 ml CH 4 /g SV and 377.02 ml CH 4 /g SV respectively. In these materials an RSI of 1:2 obtained increases of 22.56% and 37.54% compared to the RSI 1:1. Also, the kinetic analysis showed that the modified Gompertz model is the one that best fits performance, with constant differences of 7.06% between the experimental and predicted values. On the other hand, the modified Gompertz model was adjusted to the experimental results with an r2 of (0.998) and an RMSE of 4.09 ml/g SV at 17.12 ml/g SV. • The addition of an inoculum increased the rate of methane and biogas production. • The camelid manure generated methane yields between 235.49 and 377.02 ml CH 4 /g VS. • The three and four parameter sigmoid prediction models better estimated the BMP tests. • Flame manure residues provided 70.74% biodegradability results. [ABSTRACT FROM AUTHOR]

Suspended and bedload transport dynamics on rivers draining glacierized basins depend on complex processes of runoff generation together with the degree of sediment connectivity and coupling at the basin scale. This paper presents a recent dataset of sediment transport in the Estero Morales, a 27 km2 glacier-fed basin in Chile where suspended sediment concentration (SSC) and bedload (BL) fluxes have been continuously monitored during two ablation seasons (2014–2015 and 2015–1016). The relationship between discharge and SSC depends on the origin of runoff, which is higher during glacier melting, although the hysteresis index reveals that sediment sources are closer to the outlet during snowmelt. As for suspended sediment transport, bedload availability and yield depend on the origin of runoff. Bedload yield and bedload transport efficiency are higher during the glacier melting period in the first ablations season due to a high coupling to the proglacial area after the snowmelt period. Instead, on the second ablation seasons the peak of bedload yield and bedload transport efficiency occur in the snowmelt period, due to a better coupling of the lower part of the basin caused by a longer permanency of snow. Differences in volumes of transported sediments between the two seasons reveal contrasting mechanisms in the coupling dynamic of the sediment cascade, due to progressive changes of type and location of the main sources of runoff and sediments in this glacierized basin. The paper highlights the importance of studying these trends, as with retreating glaciers basins are likely producing less sediments after the "peak flow", with long-term consequences on the ecology and geomorphology of rivers downstream. [ABSTRACT FROM AUTHOR]

In this paper, information is added and comments are made about two recently described Peruvian species of Liolaemus from the montanus group: L. balagueri and L. qalaywa. When L. balagueri was described, differences from L. nazca was based on a phylogenetic analysis of a single mitochondrial locus, but without including phenotypic diagnostic traits that might differentiated them. On the other hand, L. qalaywa description was based upon specimens from Apurirnac department and intraspecific variation in meristic traits were missing. In this study, we added a molecular and morphological analyses between L. balagueri and L. nazca, supporting more rigorously the separation between these two taxa. In addition, the geographic range of L. qalaywa is extended to Cusco department (southwestern Peru), intraspecific variation of morphological characteristics and geographic information up to 79 specimens are included, and the conservation issues of this species is commented. [ABSTRACT FROM AUTHOR]

• Ecosystem services governance is shaped by power asymmetries. • There is a need for novel approaches that unravel the nature and intensity of power asymmetries. • Social network analysis can be used to investigate the different forms of power handled by actors. • Some forms of power, such as domination, strongly increase conflict probability. Power asymmetries affect the governance of natural resources but are rarely considered explicitly in ecosystem services research, which often overlooks the diversity of actors and their interactions. In this paper, we propose an innovative and easily replicable method to analyze two types of power asymmetries, using social network analysis and a power typology which distinguishes between influence and domination. We apply this method to a network of actors involved in the governance of eight ecosystem services in the Peruvian Andes. The results reveal substantial power asymmetries, of different types. Indirect managers of ecosystem services had higher influence and domination than the direct managers and beneficiaries. Businesses showed significantly lower influence than members of civil society, non-governmental organizations, and the public sector (state or decentralized organizations, public enterprises). Compared to other actors, members of the public sector had significantly higher domination, especially national actors. Domination and influence relationships strongly increased conflict probability, along with difference of domination score between two actors. A better interdisciplinary understanding of the determinants of power asymmetries can make the governance of socio-ecological systems more sustainable. [ABSTRACT FROM AUTHOR]

The upper ranges of the northern Andes are characterized by unique Neotropical, high altitude ecosystems known as paramos. These tundra-like grasslands are widely recognized by the scientific community for their biodiversity and their important ecosystem services for the local human population. Despite their remoteness, limited accessibility for humans and waterlogged soils, paramos are highly flammable ecosystems. They are constantly under the influence of seasonal biomass burning mostly caused by humans. Nevertheless, little is known about the spatial extent of these fires, their regime and the resulting ecological impacts. This paper presents a thorough mapping and analysis of the fires in one of the world's largest paramo, namely the "Complejo de Páramos" of Cruz Verde-Sumapaz in the Eastern mountain range of the Andes (Colombia). Landsat TM/ETM+ and MODIS imagery from 2001 to 2013 was used to map and analyze the spatial distribution of fires and their intra- and inter-annual variability. Moreover, a logistic regression model analysis was undertaken to test the hypothesis that the dynamics of the paramo fires can be related to human pressures. The resulting map shows that the burned paramo areas account for 57,179.8 hectares, of which 50% (28,604.3 hectares) are located within the Sumapaz National Park. The findings show that the fire season mainly occurs from January to March. The accuracy assessment carried out using a confusion matrix based on 20 reference burned areas shows values of 90.1% (producer accuracy) for the mapped burned areas with a Kappa Index of Agreement (KIA) of 0.746. The results of the logistic regression model suggest a significant predictive relevance of the variables road distance (0.55 ROC (receiver operating characteristic)) and slope gradient (0.53 ROC), indicating that the higher the probability of fire occurrence, the smaller the distance to the road and the higher the probability of more gentle slopes. The paper sheds light on fires in the Colombian paramos and provides a solid basis for further investigation of the impacts on the natural ecosystem functions and biodiversity. [ABSTRACT FROM AUTHOR]

The Neotropical subtribe Pachyphyllinae comprises orchids distributed mainly along the Andes and characterized by the monopodial type of growth. The systematic position of this taxon within Orchidaceae and its generic composition was intensively discussed, but so far no comprehensive morphological study on the group was conducted. In this paper the morphological descriptions of all genera included in Pachyphyllinae are provided and the key to their identification is presented. In addition, the taxonomic position of Raycadenco is discussed. The research revealed the existence of two distinctive species which were classified until now within Pachyphyllum or Fernandezia. Since neither the flower morphology of those two species nor the gynostemium structure fulfils the concept of any known orchid taxon, the new genus is described here under the name Valdiviesoa. The two representatives of the new taxon are illustrated and the photographs of the plants are provided. The information about their distribution and ecology are provided. The morphological characters of all Pachyphyllinae representatives are compared. [ABSTRACT FROM AUTHOR]

The Special Collection of papers in this issue of Astrobiology provides an overview of the characteristics and potential for future exploration of the Ojos del Salado volcano, located in the Andes Mountains in front of the Atacama Desert in northern Chile. The main benefits of this site compared with others are the combination of strong UV radiation, the presence of permafrost, and geothermal activity within a dry terrain. The interaction between limited snow events and wind results in snow patches buried under a dry soil surface. This leads to ephemeral water streams that only flow during daytime hours. On this volcano, which has the highest located subsurface temperature monitoring systems reported to date, seasonal melting of the permafrost is followed by fast percolation events. This is due to the high porosity of these soils. The results are landforms, shaped by the strong winds. At this site, both thermal springs and lakes (the latter arising from melting ice) provide habitats for life; a 6480 m high lake heated by volcanic activity shows both warm and cold sediments that contain a number of different microbial species, including psychrophiles. Where the permafrost melts, thawing ponds have formed at 5900 m that are dominated by populations of Bacteroidetes and Proteobacteria, while in the pond sediments and the permafrost itself Acidobacteria, Actinobacteria, Bacteroidetes, Patescibacteria, Proteobacteria, and Verrucomicrobia are abundant. In turn, fumaroles show the presence of acidophilic iron-oxidizers and iron-reducing species. In spite of the extreme conditions reported at Ojos del Salado, this site is easily accessible. [ABSTRACT FROM AUTHOR]

The cryosphere provides multiple services to society, but mountain cryosphere is shrinking at an alarming rate worldwide due to climate change, threatening natural and human systems. Adaptation to cryosphere change is essential to avoid irreversible damage and to achieve the Sustainable Development Goals. Although documenting adaptation actions and challenges is vital for preparing and implementing adaptation strategies, efforts to document and understand current adaptation practices specifically in response to cryosphere change have been limited. This paper synthesizes adaptation actions currently practiced in the mountain ranges of the Andes, Alps, Pamir, Tien Shan and Himalaya in response to cryosphere change, discusses common constraints and suggests actions for creating an enabling environment for adaptation. It identifies various adaptation measures adopted by different actors. These range from changing current practices and behaviour at household level to collaborative monitoring at regional level. However, most adaptation measures are autonomous, narrowly focused and short term, without adequate planning and government support. The physical challenges of mountain terrain, low adaptive capacities, limited knowledge and high uncertainty about future risks constrain widespread adoption of adaptation measures. Further research is needed to better understand factors influencing adaptation actions, and the policy options and responses that can overcome existing barriers. [ABSTRACT FROM AUTHOR]

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This paper presents the first experimental archaeological study to formally compare the physical characteristics of tattoos made on human skin using multiple pre-modern tools and tattooing techniques. Our project used eight tools fashioned from animal bone, obsidian, copper, and boar tusk, along with a modern steel needle, to create tattoos on the leg of co-author Danny Riday. Those tattoos were created through four different traditional, pre-electric techniques consisting of hand poking, hand tapping, incision, and subdermal tattooing. We then documented the tattoos over a six-month period to compare the results. This process revealed clear physical differences between tattoos created using different tools and methods. The resulting data is then used to assess preserved tattoos from archaeological sites in the Andes and Greenland in order to test assumptions about how those marks were created. [ABSTRACT FROM AUTHOR]

Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families. [ABSTRACT FROM AUTHOR]

The Peruvian Andes are the natural habitat of several wild blackberry species that are little known and exploited due to the lack of technological and scientific development to support their agricultural potential. In this context, a study was conducted to understand the physicochemical composition, bioactive compounds, antimicrobial activity, and in vitro multiplication of four wild blackberry (Rubus sp.) species from the northern Peruvian highlands. The results indicate that fruits of R. floribundus presented the highest content of total soluble solids (9.58 ± 1.83°Brix) and titratable acidity (1.88 ± 0.07% citric acid). The fruits of R. weberbaueri recorded the highest total phenolic content (415.06 ± 8.69 mg GAE/100 g Ff). The antioxidant capacity determined by the DPPH assay varied significantly among species, with the highest value found in fruits of R. andicola (50.27 ± 0.11 mg TE/100 g Ff). The fruit extracts of R. weberbaueri and R. andicola showed better antimicrobial activity, with Staphylococcus aureus being the most sensitive bacterium. In the in vitro multiplication phase, the results show that BAP (6-Benzylaminopurine) has a significant effect at a dose of 1.5 mg l−1 on shoot number, leaf number, and shoot length. The results may help in the management of genetic resources. [ABSTRACT FROM AUTHOR]

The genus Cinchona L. has important medicinal, cultural, and economic value and is the emblematic tree of Peru. The genus is mainly found in the cloud forests of the Andes. However, the expansion of agriculture and livestock farming in the department of Amazonas is degrading these ecosystems and has reduced the size of the genus's populations. In this work, we model the potential distribution under current conditions of three Cinchona species (C. capuli L. Anderson, C. macrocalyx Pav. Ex DC., and C. pubescens Vahl.) to identify areas with a high likelihood of species presence and their key conservation and reforestation zones. We fitted a maximum entropy (MaxEnt) model using nineteen bioclimatic variables, three topographic variables, nine edaphic variables, and solar radiation. Under current conditions, the potential distribution of C. capuli covers 17.22% (7243.98 km2); C. macrocalyx, 29.11% (12,238.91 km2); and C. pubescens, 22.94% (9647.63 km2) of the study area, which was mostly located in central and southern Amazonas. Only 24.29% (25.51% of C. capuli, 21.02% of C. macrocalyx, and 26.35% of C. pubescens) of the potential distributions are within protected areas, while 10,987.22 km2 of the surface area of the department of Amazonas is degraded, of which 29.80% covers the area of probable occurrence of C. capuli, 38.72% of C. macrocalyx, and 34.82% of C. pubescens. Consequently, it is necessary to promote additional conservation strategies for Cinchona, including the establishment of new protected areas and the recovery of degraded habitats, in order to protect this species. [ABSTRACT FROM AUTHOR]

Early growth of atmospheric particles is essential for their survival and ability to participate in cloud formation. Many different atmospheric vapors contribute to the growth, but even the main contributors still remain poorly identified in many environments, such as high-altitude sites. Based on measured organic vapor and sulfuric acid concentrations under ambient conditions, particle growth during new particle formation events was simulated and compared with the measured particle size distribution at the Chacaltaya Global Atmosphere Watch station in Bolivia (5240 m a.s.l.) during April and May 2018, as a part of the SALTENA (Southern Hemisphere high-ALTitude Experiment on particle Nucleation and growth) campaign. Despite the challenging topography and ambient conditions around the station, the simple particle growth model used in the study was able to show that the detected vapors were sufficient to explain the observed particle growth, although some discrepancies were found between modeled and measured particle growth rates. This study, one of the first of such studies conducted on high altitude, gives insight on the key factors affecting the particle growth on the site and helps to improve the understanding of important factors on high-altitude sites and the atmosphere in general. Low-volatility organic compounds originating from multiple surrounding sources such as the Amazonia and La Paz metropolitan area were found to be the main contributor to the particle growth, covering on average 65 % of the simulated particle mass in particles with a diameter of 30 nm. In addition, sulfuric acid made a major contribution to the particle growth, covering at maximum 37 % of the simulated particle mass in 30 nm particles during periods when volcanic activity was detected on the area, compared to around 1 % contribution on days without volcanic activity. This suggests that volcanic emissions can greatly enhance the particle growth. [ABSTRACT FROM AUTHOR]

Snow modelling is often hampered by the availability of input and calibration data, which can affect the choice of models, their complexity, and transferability. To address the trade-off between model parsimony and transferability, we present the Generalizable Empirical Model of Snow Accumulation and Melt (GEMS), a machine-learning-based model, which requires only daily precipitation, temperature or its daily diurnal cycle, and basic topographic features to simulate snow water equivalent (SWE). The model embeds a support vector regression pretrained on a large dataset of daily observations from a diverse set of the SNOwpack TELemetry Network (SNOTEL) stations in the United States. GEMS does not require any user calibration, except for the option to adjust the temperature threshold for rain–snow partitioning, though the model achieves robust simulation results with the default value. We validated the model with long-term daily observations from numerous independent SNOTEL stations not included in the training and with data from reference stations of the Earth System Model–Snow Model Intercomparison Project. We demonstrate how the model advances large-scale SWE modelling in regions with complex terrain that lack in situ snow mass observations for calibration, such as the Pamir and Andes mountains, by assessing the model's ability to reproduce daily snow cover dynamics. Future model improvements should consider the effects of vegetation, improve simulation accuracy for shallow snow in warm locations at lower elevations, and possibly address wind-induced snow redistribution. Overall, GEMS provides a new approach for snow modelling that can be useful for hydroclimatic research and operational monitoring in regions where in situ snow observations are scarce. [ABSTRACT FROM AUTHOR]

During the night of March 31st, 2017, a severe precipitation event affected the city of Mocoa, in the tropical Andes. Total 24-h accumulated precipitation during that day was the fourth largest on record. Satellite data shows that the event was associated with a Mesoscale Convective System (MCS) that formed over the Amazon and moved westward, reaching the tropical Andes. Reanalysis data suggests that a rapid intensification of the Orinoco Low-Level Jet (OLLJ) traveling southwestward parallel to the Andes was a precursor that favored the zones of convergence for MCS formation. Upstream intensification of the OLLJ was evident 8 h prior to the Mocoa precipitation event. Given the lack of a dense network of observations in this understudied region, we use the Weather Research and Forecasting model (WRF) to explore the plausible mesoscale structures in the OLLJ region associated with the initiation and development of the MCS. We study an ensemble of simulations with different grid spacings (12, 4 and 1.3 km) and Planetary Boundary Layer (PBL) schemes (YSU, MYNN and QNSE). The more realistic MCSs were obtained with the QNSE and YSU schemes, given that the corresponding simulations included a density current in the lowest levels moving parallel to the Andes, with a sharp line of convergence and large vertical velocities over the leading edge of the mesoscale disturbance. In contrast, the MYNN scheme produced a weaker OLLJ and no density current. It is suggested that the stronger vertical mixing in the MYNN scheme was associated with the vertical dilution of the OLLJ, and with a much weaker low-level traveling perturbation via the upward radiation of energy by gravity waves. Our results help to better understand flood-producing extreme events over the poorly studied Andes-Amazon region and provide the groundwork for improved predictability of such storms. [ABSTRACT FROM AUTHOR]

The aerosol and precipitable water vapor (PW) distribution over the tropical Andes region is characterized using Aerosol Robotic Network (AERONET) observations at stations in Medellin (Colombia), Quito (Ecuador), Huancayo (Peru), and La Paz (Bolivia). AERONET aerosol optical depth (AOD) is interpreted using PM2.5 data when available. Columnar water vapor derived from ozone soundings at Quito is used to compare against AERONET PW. MERRA-2 data are used to complement analyses. Urban pollution and biomass burning smoke (BBS) dominate the regional aerosol composition. AOD and PM2.5 yearly cycles for coincident measurements correlate linearly at Medellin and Quito. The Andes cordillera's orientation and elevation funnel or block BBS transport into valleys or highlands during the two fire seasons that systematically impact South America. The February–March season north of Colombia and the Colombian-Venezuelan border directly impacts Medellin. Possibly, the March aerosol signal over Quito has a long-range transport component. At Huancayo and La Paz, AOD increases in September due to the influence of BBS in the Amazon. AERONET PW and sounding data correlate linearly but a dry bias with respect to soundings was identified in AERONET. PW and rainfall progressively decrease from north to south due to increasing altitude. This regional diagnosis is an underlying basis to evaluate future changes in aerosol and PW given prevailing conditions of rapidly changing atmospheric composition. [ABSTRACT FROM AUTHOR]

A multiscale analysis of the environment supporting tornadoes in southeast South America (SESA) was conducted based on a self-constructed database of 74 reports. Composites of environmental and convective parameters from ERA5 were generated relative to tornado events. The distribution of the reported tornadoes maximizes over the Argentine plains, while events are rare close to the Andes and south of Sierras de Córdoba. Events are relatively common in all seasons except in winter. Proximity environment evolution shows enhanced instability, deep-layer vertical wind shear, storm-relative helicity, reduced convective inhibition, and a lowered lifting condensation level before or during the development of tornadic storms in SESA. No consistent signal in low-level wind shear is seen during tornado occurrence. However, a curved hodograph with counterclockwise rotation is present. The Significant Tornado Parameter (STP) is also maximized prior to tornadogenesis, most strongly associated with enhanced CAPE. Differences in the convective environment between tornadoes in SESA and the U.S. Great Plains are discussed. On the synoptic scale, tornado events are associated with a strong anomalous trough crossing the southern Andes that triggers lee cyclogenesis, subsequently enhancing the South American low-level jet (SALLJ) that increases moisture advection to support deep convection. This synoptic trough also enhances vertical shear that, along with enhanced instability, sustains organized convection capable of producing tornadic storms. At planetary scales, the tornadic environment is modulated by Rossby wave trains that appear to be forced by convection near northern Australia. Madden–Julian oscillation phase 3 preferentially occurs 1–2 weeks ahead of tornado occurrence. Significance Statement: The main goal of this study is to describe what atmospheric conditions (from local to global scales) are present prior to and during tornadic storms impacting southeast South America (SESA). Increasing potential for deep convection, wind shear, and potential for rotating updrafts, as well as reducing convective inhibition and cloud-base height, are predominant a few hours before and during the events in connection to low-level northerly winds enhancing moisture transport to the region. Remote convective activity near northern Australia appears to influence large-scale atmospheric circulation that subsequently triggers convective storms supporting tornadogenesis 1–2 weeks later in SESA. Our findings highlight the importance of accounting for atmospheric processes occurring at different scales to understand and predict tornado occurrences. [ABSTRACT FROM AUTHOR]

Copyright of Latin American & Latinx Visual Culture is the property of University of California Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Continental arcs are associated with volcanism concentrated into two main belts—the main arc and back arc, often separated by fold and thrust belts. The Loicas Trough, Argentina, is a post-orogenic extensional feature that obliquely cuts the fold and thrust belts. The trough hosts large Pliocene–Holocene volcanic centres, including Domuyo and Tromen, that lie between the main arc and back arc and thus provide a rare window into this setting. We present major and trace element data for the Loicas Trough, which we combine with geochemical modelling using the Magma Chamber Simulator (MCS) to explore the origin and evolution of the volcanism. The lavas display a wide continuous range from alkaline basalts to subalkaline rhyolites. Trace elements reveal variable extents of arc enrichment (2 < Nb/U < 28), which correlate with proximity to the trench and differentiation indices. Our results and MCS models indicate that the Loicas Trough parental magmas formed from compositionally zoned mantle. Best-fit models indicate that the differentiation occurs at middle and upper crustal levels, in sharp contrast to lower crustal hot zones beneath main arcs. Assimilation of partial crustal melts drives compositional evolution and obscures source signatures. Pure or high fraction end-member partial crustal melts are also identified at Domuyo based on their low Ba (~ 250 ppm) and moderate Sc contents (~ 8 ppm). We find evidence of similar lavas in transtensional settings adjacent to continental arcs worldwide, which do not adhere to the main versus back arc volcanism binary. We suggest the term arc-adjacent magmatism, where compositions are mainly controlled by extensive assimilation and reworking in the middle to upper crust. [ABSTRACT FROM AUTHOR]

Copyright of Acta Biológica Colombiana is the property of Universidad Nacional de Colombia, Facultad de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Puno-Peruvian high plateau have been shaped by humans over the last 8000 years. The Waru Waru system is a direct result of the agricultural activities of the pre-Inca in the last 2000 years. The present study was conducted in the circumlacustrine zone of Titicaca (445,532 ha) near the city of Puno, Peru. The parent material of the soils originates from the Quaternary alluvial and lacustrine deposits within the high plateau with fl at landscapes, and the land is used for temporary and perennial cultivation as well as extensive natural pasture. The entire region was assessed through a preliminary soil survey, based on which three soil profi les were selected as representative Waru Waru soil structures. The soil samples were subjected to morphological and physicochemical analyses and the genesis in relation to historical use was investigated. The results showed that sandy loam and clay loam textures dominate and the average sand content is 52%, giving the parent material acidic characteristics. The soils are typically covered by natural grassland, with adequate drainage conditions and the presence of a hydrological discontinuity at a depth of 60 cm. The stagnic properties of the soils are related to the seasonally wet and paleohydromorphic conditions originating from paleolacustrine conditions and fl ooding. The soils exhibited high variability in base content, with pH ranging from acidic to neutral and evidence of ion leaching processes and incipient concentration of salts at depth. The predominant soils were Stagnosols, Cambisols and Phaeozems in the same order (IUSS Working Group WRB, 2022), corresponding to Inceptisols and Mollisols (Soil Survey Staff, 2022a). The Waru Waru agricultural system covers an area of approximately 123,000 ha, with 5% of this area consisting of natural grasslands. The degradation of the traditional agriculture system (Waru Waru) is infl uenced by the socio-cultural dynamics and modernization of the agricultural sector. [ABSTRACT FROM AUTHOR]

Background: Global warming and climate change are threats to the world. Warmer temperatures and changes in precipitation patterns alter water availability and increase the occurrence of extreme weather events. South America and the Andes are vulnerable regions to climate change due to inequity and the uneven distribution of resources. Climate change evaluation often relies on the use of general circulation models (GCMs). However, the spatial resolution is too coarse and does not provide a realistic climate representation at a local level. This is of particular importance in mountain areas such as the Andes range, where the heterogeneous topography requires a finer spatial resolution to represent the local physical processes. To this end, statistical and/or dynamical downscaling methods are required. Several approaches and applications of downscaling procedures have been carried out in the countries of this region, with different purposes and performances. However, the main objective is to improve the representation of meteorological variables such as precipitation and temperature. A systematic review of these downscaling applications will identify the performance of the methods applied in the Andes region for the downscaling of precipitation and temperature. In addition, the meta-analysis could detect factors influencing the performance. The overall goal is to highlight promising methods in terms of fitness for use and identify knowledge gaps in the region. Methods: The review will search and examine published and grey literature on downscaling applications of temperature and precipitation in the Andes region. Predetermined criteria for eligibility will allow the screening of the evidence. Then, the method used in each application will be coded and mapped according to the country, purpose, variable, and type of downscaling. At the same time, quantitative and qualitative data will be extracted. The performance metrics are particularly interesting for this review. A meta-analysis will be conducted for those studies with comparable metrics. A narrative synthesis, maps and heatmaps will show the results. Tables, funnel plots, and meta-regressions will present the meta-analysis. Throughout the review, a critical appraisal step will categorize the validity of the evidence. [ABSTRACT FROM AUTHOR]

Two novel species of Psalmopoeus Pocock, 1895 are described from the north-western and central-western slopes of the Cordillera Occidental of the Andes mountain range in Ecuador. The new species are easily differentiated from other congeners of Psalmopoeus by spermathecae and male palpal bulb morphology and a comparatively distant distribution to the type localities of the geographically nearest known congeners. The diagnosis of P. ecclesiasticus Pocock, 1093 is revised and updated, considering the novel species and observations on spermatheca of this species. Likewise, an evaluation is provided for the new species in terms of conservation due to the various threats impacting ecosystems and ecosystem services of their type localities. Finally, the importance of theraphosid spiders in Ecuador and South America and their possible conservation requirements are discussed and assessed. [ABSTRACT FROM AUTHOR]

Plants absorb nutrients and water through their roots, and modulate soil biogeochemical cycles. The mechanisms of water and nutrient uptake by plants depend on climatic and edaphic conditions, as well as the plant root system. Soil solution is the medium in which abiotic and biotic processes exchange nutrients, and nutrient concentrations vary with the abundance of reactive minerals and fluid residence times. High-altitude ecosystems of the tropical Andes are particularly interesting to study the association between vegetation patterns, soil hydrology and soil nutrient availability. The páramo landscape forms a vegetation mosaic of bunch-grasses, cushion-forming plants and forests. In the nutrient-depleted nonallophanic Andosols, the plant rooting depth varies with drainage and soil moisture conditions. Vegetation composition is a relevant indicator of rock-derived nutrient availability in soil solutions. The soil solute chemistry revealed patterns in plant available nutrients that were not mimicking the distribution of total rock-derived nutrients nor the exchangeable nutrient pool, but clearly resulted from strong biocycling of cations and removal of nutrients from the soil by plant uptake or deep leaching. Our findings have important implications for future management of Andean páramo ecosystems where vegetation type distributions are dynamically changing as a result of warming temperatures and anthropogenic disturbances. Such alterations may not only lead to changes in soil hydrology and solute geochemistry but also to complex changes in weathering rates and solute export downstream with effects on nutrient availability in Andean rivers and high-mountain lakes. [ABSTRACT FROM AUTHOR]

Geomorphological changes have played a central role in species diversification by promoting vicariance through barriers that reduce gene flow. However, niche evolution leading to local adaptations to new environments may also drive speciation, regardless of the presence of geographical barriers. Here, we assessed the role of geological changes and climatic niche evolution in the diversification of true frogs of the Rana palmipes species group (Ranidae) in Central and South America. We investigated if the evolutionary history of species was shaped by vicariance and ecological niche conservatism, founder events followed by niche divergence or both by estimating ancestral areas. Then, we used a phyloclimatic analysis to quantify niche overlap and tested for niche conservatism between species. We found a pattern of both vicariance and successive founder events from north to south, with lineages reaching newly formed areas during the formation of Central America throughout the Miocene and Pliocene, and at least two dispersal events into South America. Species presented low overlaps in climatic niche and phyloclimatic analysis did not recover a phylogenetic signal. Profiles of niche occupancy diverging over time and high values of disparity between clades indicate niche divergence during the evolutionary history of species. Our results indicate an interplay between niche evolution and geological changes acting on Rana palmipes species group diversification. Speciation events were probably driven by vicariance and ecological speciation after successive dispersal events, while species occupied new areas available during the uplift of Talamanca and Andes Mountain ranges. [ABSTRACT FROM AUTHOR]

Intensification of agricultural land use in traditional Andean production landscapes has led to changes in the provision of nature's contributions to people (NCP) that can threaten people's wellbeing. Understanding local stakeholders' valuation of these NCP is crucial for improving land use decisions. We implemented a spatially explicit and participatory NCP valuation method, using semi-structured interviews and participatory mapping, followed by a spatial multi-criteria decision analysis, to identify priority areas for NCP provision in a highly intensified production landscape in the Colombian Andes. We considered multiple value types, ecological, economical and sociocultural, and the points of view of different actors, orienting this towards decision-making on land use. Our results show that local actors can identify and value a wide range of NCP. However, there are also significant differences between actors. Environmentalists attached special importance to regulating NCP, while agricultural laborers focused more on agriculture-related material NCP. As we expected, tourism entrepreneurs especially valued non-material NCP related to their business experiences. Small-scale farmers tended to put more importance on regulating and non-material NCP than big farmers did. Although there was a consensus between actors as to the importance of natural ecosystems for NCP provision, agricultural actors tended to attach more importance to material NCP in areas deemed important for regulating and non-material NCP by other actors. Our main results confirm the importance of involving different stakeholders in spatial NCP valuation exercises, recognizing their different points of view to help identify possible trade-offs and synergies related to land use. [ABSTRACT FROM AUTHOR]

Copyright of Acta Zoologica Lilloana is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As an alternative to the current technologies, we explored the feasibility of using low cost and massive use of digital cameras as photometric sensors to retrieve the atmospheric total optical depth (τ) in the urban area of a city in the Colombian Andes. This study proposes a simple way to estimate τ from digital processing of images of the Sun based on the Beer-Bouguer-Lambert law Langley's linear fitting for the colour levels in channels red, green, and blue registered by the pixels of cameras' sensors. From February to March 2022, the τ values retrieved from the images were correlated to the retrieved values from a solar spectral radiometer (SSR). We found that τ is sensible to the featured changes in the local atmosphere and to the cameras' exposure parameters setup. Under conditions of partly clear sky, around 80% (r > 0.8) of the τ values from cameras showed a linear correspondence to those retrieved from SSR system. Its spectral dependency (τ _red < τ _green < τ _blue) is in accordance with the physical phenomena in light-atmosphere interaction. The results suggest that the methodology applied can be used for monitoring the atmosphere at any geographical location in the world. [ABSTRACT FROM AUTHOR]

Caryophyllaceae with a cushion-like life form occur with a large number of species at the higher altitudes of the Andes (3500–5000 m) and have evolved convergently in several different lineages. Based on molecular phylogenetic analysis it is shown that members of the former genera Plettkea and Pycnophyllopsis, but also certain species previously classified as Arenaria constitute a subclade nested within the monophyletic genus Stellaria. Both plastid (trnK-matK-psbA + trnL-F) and nuclear (nrITS) trees converged on such a highly supported 'Plettkea' clade. Morphologically, the members of the 'Plettkea' subclade of Stellaria are further characterized by reduced to completely absent petals and seeds with a more or less conspicuous tuberculate testa. This clade is described as S. sect. Plettkea (Mattf.) Montesinos & Borsch. Species-level relationships within S. sect. Plettkea are also congruently inferred by plastid and nuclear genomic compartments, with three further sublineages recognized: Altogether, our detailed taxonomic revision showed that the 'Plettkea' clade in fact constitutes an Andean radiation of 21 species within Stellaria, four of which are described as new to science. Earlier treatments indicated just a few species with a putative placement. The results of this investigation underscore the importance of fieldwork and integrated molecular-morphological approaches to assess the species diversity in Andean plant groups. In addition to the phylogenetic analysis, we provide a taxonomic backbone including all names and types, descriptions and information on distribution and ecology and a key for identification. Regarding the next relatives of the S. sect. Plettkea clade, our plastid trees depict the 'Nitentes' clade of Stellaria as sister, whereas nrITS instead suggests a sister group relationship of the 'Nitentes' with the speciose 'Larbreae' clade. Our inferred relationships of major clades further deviate from published molecular trees by indicating an early branching position of the 'Petiolares' clade. Citation: Montesinos-Tubée D. B. & Borsch T. 2023: Molecular phylogenetics and morphology reveal the Plettkea lineage including several members of Arenaria and Pycnophyllopsis to be a clade of 21 South American species nested within Stellaria (Caryophyllaceae, Alsineae) Version of record first published online on 21 December 2023 ahead of inclusion in December 2023 issue. Las Caryophyllaceae, con forma de vida en matas o almohadillas, se encuentran en las mayores altitudes de los Andes (3500–5000 m) con un gran número de especies y han tenido una evolución convergente en diversos linajes. Análisis filogenéticos moleculares, recuperan un subclado anidado dentro del género monofilético Stellaria, constituido por los miembros previamente clasificados en Plettkea y Pycnophyllopsis y especies clasificadas hasta ahora en Arenaria. Tanto los árboles de plástidos (trnK-matK-psbA + trnL-F) como los nucleares (nrITS) convergen en un clado de 'Plettkea' altamente apoyado estadísticamente. Morfológicamente, los miembros del subclado 'Plettkea' de Stellaria se caracterizan, además, por compartir pétalos reducidos o completamente ausentes y semillas con un tegumento tuberculado más o menos conspicuo. El subclado se valida como S. sect. Plettkea (Mattf.) Montesinos & Borsch. Las relaciones a nivel de especie dentro de esta sección también se infieren congruentemente por compartimentos genómicos plastidiales y nucleares, con tres sublinajes. En conjunto, nuestra detallada revisión taxonómica mostró que el clado Plettkea constituye una radiación andina de 21 especies dentro de Stellaria, cuatro de las cuales se describen como nuevas para la ciencia. Tratamientos anteriores indicaban sólo unas pocas especies con una ubicación putativa. Los resultados de esta investigación destacan la importancia del trabajo de campo y la integración de métodos moleculares y morfológicos para evaluar la diversidad de especies en los grupos de plantas andinas. Además del análisis filogenético, proporcionamos una columna vertebral taxonómica que incluye todos los nombres y datos de los tipos nomenclaturales. Se proporcionan descripciones e información sobre distribución y ecología así como una clave para identificarlas. Con respecto a los parientes próximos del clado de S. sect. Plettkea, nuestros árboles de plástidos muestran al clado 'Nitentes' de Stellaria como hermano, mientras que nrITS sugiere más bien una relación de grupo hermano de los 'Nitentes' con el clado 'Larbreae'. Las relaciones inferidas de los clados principales se desvían aún más de los árboles moleculares publicados previamente, al indicar una posición de ramificación temprana del clado 'Petiolares'. [ABSTRACT FROM AUTHOR]

Land cover classification, generated from satellite imagery through semantic segmentation, has become fundamental for monitoring land use and land cover change (LULCC). The tropical Andes territory provides opportunities due to its significance in the provision of ecosystem services. However, the lack of reliable data for this region, coupled with challenges arising from its mountainous topography and diverse ecosystems, hinders the description of its coverage. Therefore, this research proposes the Tropical Andes Land Cover Dataset (TALANDCOVER). It is constructed from three sample strategies: aleatory, minimum 50%, and 70% of representation per class, which address imbalanced geographic data. Additionally, the U-Net deep learning model is applied for enhanced and tailored classification of land covers. Using high-resolution data from the NICFI program, our analysis focuses on the Department of Antioquia in Colombia. The TALANDCOVER dataset, presented in TIF format, comprises multiband R-G-B-NIR images paired with six labels (dense forest, grasslands, heterogeneous agricultural areas, bodies of water, built-up areas, and bare-degraded lands) with an estimated 0.76 F1 score compared to ground truth data by expert knowledge and surpassing the precision of existing global cover maps for the study area. To the best of our knowledge, this work is a pioneer in its release of open-source data for segmenting coverages with pixel-wise labeled NICFI imagery at a 4.77 m resolution. The experiments carried out with the application of the sample strategies and models show F1 score values of 0.70, 0.72, and 0.74 for aleatory, balanced 50%, and balanced 70%, respectively, over the expert segmented sample (ground truth), which suggests that the personalized application of our deep learning model, together with the TALANDCOVER dataset offers different possibilities that facilitate the training of deep architectures for the classification of large-scale covers in complex areas, such as the tropical Andes. This advance has significant potential for decision making, emphasizing sustainable land use and the conservation of natural resources. [ABSTRACT FROM AUTHOR]

The aseismic Nazca Ridge produces localized flat-slab subduction beneath the South American margin at latitudes 10° to 15° S. The geological evolution and the spatio-temporal pattern of deformation of the upper plate have been strongly influenced by the presence of the flat slab. In this study, we investigated the lithospheric thermal structure of this region by elaborating a 2D geothermal model along a section across the top of the Nazca Ridge, the Peru–Chile trench, the Andean Cordillera, and the Amazonian Basin, for a total length of 1000 km. For the sake of modelling, the crust of the overriding plate was subdivided into two parts, i.e., a sedimentary cover (including the entire lithostratigraphic sequence) and a crystalline basement. Applying an analytical methodology, we calculated geotherms and isotherms by setting (i) thickness, (ii) density, (iii) heat production, and (iv) thermal conductivity for each geological unit and considering (v) heat flux at the Moho, (vi) frictional heating produced by faults, and (vii) plate convergence rate. The resulting model could make a significant advance in our understanding of how flat slab geometry associated with the Nazca Ridge subduction affects the thermal structure and hence the tectonic evolution of the region. [ABSTRACT FROM AUTHOR]

This work quantifies the uncertainty of accumulation-season peak snow water storage in the portions of the midlatitude American Cordillera where snow is a dominant driver of hydrology. This is accomplished through intercomparison of commonly used global and regional products over the Western United States (WUS) and Andes domains, which have similar hydrometeorology but are disparate with respect to the amount of available in situ information. The recently developed WUS Snow Reanalysis (WUS-SR) and Andes Snow Reanalysis (Andes-SR) datasets, which have been extensively verified against in situ measurements, are used as baseline reference datasets in the intercomparison. Relative to WUS-SR climatological peak snow water equivalent (SWE) storage (269 km 3), high- and moderate-resolution products (i.e., those with resolutions less than ∼10 km) are in much better agreement (284±14 km 3 ; overestimated by 6 %) compared to low-resolution products (127±54 km 3 ; underestimated by 53 %). In comparison to the Andes-SR peak snow storage (29 km 3), all other products show large uncertainty and bias (19±16 km 3 ; underestimated by 34 %). Examination of spatial patterns related to orographic effects showed that only the high- to moderate-resolution Snow Data Assimilation System (SNODAS) and University of Arizona (UA) products show comparable estimates of windward–leeward SWE patterns over a subdomain (Sierra Nevada) of the WUS. Coarser products distribute too much snow on the leeward side in both the Sierra Nevada and Andes, missing orographic and rain shadow patterns that have important hydrological implications. The uncertainty of peak seasonal snow storage is primarily explained by precipitation uncertainty in both the WUS (R2=0.55) and Andes (R2=0.84). Despite using similar forcing inputs, snow storage diverges significantly within the ECMWF Reanalysis v5 (ERA5) (i.e., ERA5 vs. ERA5-Land) products and the Global Land Data Assimilation System (GLDAS) (modeled with Noah, Variable Infiltration Capacity (VIC), and Catchment model) products due to resolution-induced elevation differences and/or differing model process representation related to rain–snow partitioning and accumulation-season snowmelt generation. The availability and use of in situ precipitation and snow measurements (i.e., in WUS) in some products adds value by reducing snow storage uncertainty; however, where such data are limited, i.e., in the Andes, significant biases and uncertainty exist. [ABSTRACT FROM AUTHOR]

Vampyressa melissa is a poorly known phyllostomid bat listed as vulnerable by the International Union for Conservation of Nature (IUCN). Since its description in 1926, fewer than 40 V. melissa have been reported in the literature, and less than half of these may have been correctly identified. During revisionary studies of Vampyressa, we uncovered two previously unrecognized species related to V. melissa, all associated with higher elevation habitats (>1400 m), one from the Andes of Colombia (Vampyressa sinchi, new species) and the other from western Panama (Vampyressa elisabethae, new species) revealing that V. melissa, as traditionally defined, is a composite of at least three species. In this paper, we provide a restricted diagnosis for the genus Vampyressa, an emended diagnosis of V. melissa, and descriptions of the two new species. The separation of these frugivorous bats, previously identified as V. melissa, into three isolated upper-elevation species, each having restricted distributions further highlights their fragile conservation status. [ABSTRACT FROM AUTHOR]