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The northern Andes of southern Colombia contain a rich geologic history recorded by Proterozoic to Cenozoic metamorphic, igneous, and sedimentary rocks. The region plays a pivotal role in understanding the evolution of topography in northwestern South America and the development of large river systems, such as the Amazon, Orinoco, and Magdalena rivers. However, understanding of the basement framework has been hindered by challenging access, security concerns, tropical climate, and outcrop scarcity. Further, an insufficient geochronologic characterization of Andean basement complicates provenance interpretations of adjacent basins and restricts understanding of the paleogeographic evolution of southern Colombia. To address these issues, this paper presents a zircon U-Pb geochronological dataset derived for 24 bedrock samples and 19 modern river samples. The zircon U-Pb results reveal that the Eastern Cordillera of southern Colombia is underlain by basement rocks that originated in various tectonic events since ca. 1.5 Ga, including the accretion of discrete terranes. The oldest rocks, found in the Garzon Massif, are high-grade metamorphic rocks with contrasting Proterozoic protolith crystallization ages. Whereas the SW part of the massif formed during the Putumayo Orogeny (ca. 1.2-0.9 Ga), we report orthogneisses for the NE segment with protoliths formed at ca. 1.5 Ga, representing the NW continuation of the Rio Negro Jurena province of the Amazonian Craton. In contrast, crystalline rocks of the Central Cordillera primarily consist of Permian-Triassic (ca. 270-250 Ma) and Jurassic-Cretaceous (ca. 180-130 Ma) igneous rocks formed in a magmatic arc. In southernmost Colombia, the Putumayo Mountains mainly consist of Jurassic-Cretaceous (180-130 Ma) plutonic and volcanic rocks. Furthermore, we analyzed the heavy mineral abundances in modern river sands in southern Colombia (spanning 1°N-5°N) and found that key minerals such as garnet and epidote can be utilized to trace highgrade metamorphic and igneous lithologies, respectively, in the river catchments. The differentiation of basement ages for separate tectonic provinces, combined with heavy mineral abundances in modern sands, can serve as unique fingerprints in provenance analyses to trace the topographic and exhumational evolution of different Andean regions through time. [ABSTRACT FROM AUTHOR]

Recent field expeditions to the Andes and herbarium research resulted in the discovery of a new species of Drymonia (Gesneriaceae). Drymonia tomentosa J.L.Clark & Clavijo is described from the western Andean slopes of northern Ecuador and southern Colombia. The new species is differentiated from other congeners by the presence of a tomentose indumentum on the stems, stout shoots, broadly oblong leaves, and calyx lobes with broadly rounded apices. Based on IUCN guidelines, a preliminary conservation status is assigned as Least Concern (LC). [ABSTRACT FROM AUTHOR]

The growing deforestation of tropical forests requires the implementation of restoration actions capable of assisting the recovery of biodiversity and the functioning of these ecosystems. This research aimed to identify the environmental factors that influence the abundance and diversity of woody plant recruitment in an Andean forest restoration project in Medellin (Colombia). Data from woody plant individuals taller than 80 cm were collected in 22 plots of 200·m−2. The environmental factors selected were edaphic variables, plantation structure, slope, elevation, prior land use, and landscape forest cover. Generalized linear models (GLM) were used to analyze recruitment densit and Linear Mixed Models (LMM) to assess recruited species richness, diversity, and dominance. Woody plant recruitment attributes in our study area were similar to those of secondary succession in an Andean forest, but planted trees contributed little to recruitment density and diversity. While recruitment density was affected by slope, canopy closure, and landscape forest cover, recruitment diversity was influenced by physical (bulk density) and chemical (pH, aluminum, Cation Exchange Capacity) edaphic factors, planted tree diversity (species richness and composition), canopy closure, and the mortality rate of planted trees. We conclude that sites with lower mortality rates of planted trees and denser canopies enhance both recruitment density and diversity, indicating a synergy between active restoration and passive regeneration processes. [ABSTRACT FROM AUTHOR]

Background: Rabies virus (RABV) is the etiologic agent of rabies, a fatal brain disease in mammals. Rabies circulation has historically involved the dog has the main source of human rabies worldwide. Nevertheless, in Colombia, cats (Felis catus) have become a relevant species in the epidemiology of rabies. Aims: To characterize rabies cases in humans in Colombia in the last three decades in the context of the epidemiology of the aggressor animal. Materials and Methods: We conducted a retrospective longitudinal epidemiological study of human rabies caused by cats' aggression, collecting primary and secondary information. Variables considered included the demography of the patient, symptoms, information about the aggressor animal as the source of infection and the viral variant identified. Results: We found that the distribution of rabies incidence over the years has been constant in Colombia. Nevertheless, between 2003 and 2012 a peak of cases occurred in rural Colombia where cats were the most frequent aggressor animal reported. Most cats involved in aggression were unvaccinated against rabies. Cat's clinical signs at the time of the report of the human cases included hypersalivation and changes in behaviour. Human patients were mostly children and female and the exposure primarily corresponded to bite and puncture lacerations in hands. The RABV lineage detected in most cases corresponded to variant 3, linked to the common vampire bat (Desmodus rotundus). The geographical presentation of cat borne RABV in humans occurred along the Andes mountains, epidemiologically known as the rabies red Andean corridor. Discussion: By finding cats as the primary source of rabies spillover transmission in Colombia, this report highlights the importance of revising national rabies control and prevention protocol in countries in the Andes region. Conclusion: Our results demonstrate that rabies vaccination for outdoor cats needs to prioritize to reduce the number of rabies‐related human deaths. [ABSTRACT FROM AUTHOR]

The mortiño (Vaccinium floribundum Kunth), belonging to the Ericaceae family, is a native species of the Ecuadorian paramos. It has a shrub-like habit and produces edible fruits. In the Neotropics, it is primarily found in the Andes of Colombia and Ecuador, thriving in humid environments up to an elevation of 3700 m above sea level. In this review, a selection of studies was carried out that evaluated the taxonomy, reproduction biology, and nutraceutical, environmental properties, and industrial use of the mortiño (V. floribundum). The data gathered from various bioassays were essential in determining the appropriate techniques for tissue differentiation and assessing the quality of resulting plants. This work aims to generate a deep knowledge of the cultivation of mortiño, as well as the properties of its fruits and the benefits they provide for health. These are rich in compounds with antioxidant activity, so the consumption of V. floribundum fruits is related to health benefits. Besides, the environmental role of V. floribundum and its applications in various industries, especially in the development of nanoparticles contributes to the valorization of this plant. Overall, this research contributes to establishing sustainable methods for the propagation of Vaccinium floribundum, ensuring its successful cultivation and utilization for both commercial purposes and ecological preservation. [ABSTRACT FROM AUTHOR]

The high Andean mountains are ecosystems subject to high human pressure activities, resulting in disturbed areas increasingly dominating the landscapes. However, there needs to have more knowledge about the contributions of different vegetation coverages and species to global diversity at the local level. For three consecutive years, we studied a guild of fruit-feeding butterflies in four different land covers (cloud forests, paramo, mixed anthropogenic habitats, and cattle pastures) in the northern Andes in Colombia, analyzing the diversity and structure of the butterfly assemblage in the region. The assembly showed significant differences between land covers. The mixed habitat was the most diverse in order q1 (exponential of Shannon entropy) and q2 (inverse of Gini-Simpson dominance index) diversity, and the cloud forest contained the higher abundance and species richness. Abundance decreased from forest to pasture, significantly reducing diversity in pastures, with cloud forest and paramo containing the key endemic species. These results indicate the value of landscape diversity in providing resources and conditions required for the diversity conservation of high Andean butterflies. Implications for insect conservation: This study highlights the significance of the heterogeneity of natural landscape components in maintaining and preserving the diversity of butterfly assemblages in high Andean environments. Current conservation plans often tend to focus on paramo habitats, our findings highlight the crucial role of including the surrounding cloud forest and associated secondary forest in the design of effective conservation strategies. The analysis revealed a high complementarity between paramo and cloud forest assemblages, with each habitat type contributing significantly to the regional species pool. This underscores the interconnectedness and interdependence of these habitats, indicating that a comprehensive approach that considers both paramo and cloud forest ecosystems is essential for conserving the full diversity of butterfly species in the region. Moreover, our results demonstrate that cattle pastures exhibit extremely low butterfly species richness and possess a community structure that is distinctly different from native habitats. [ABSTRACT FROM AUTHOR]

Aim: Human‐driven landscape processes such as habitat loss and fragmentation act on biodiversity, but their effects are mediated by the spatial scale at which they are observed. We aim to analyse the scale‐of‐effects (direction and spatial extent) of landscape‐scale processes that best explain species richness and abundance across epiphyte communities. Location: Neotropics, Northern Andes, Colombia, Eastern cordillera. Taxon: Vascular epiphytes, Orchidaceae. Methods: We used field data to unravel the scale‐of‐effect of three landscape processes—habitat loss (forest cover), fragmentation (number of patches) and edge effects (edge density)—on epiphyte biodiversity. Vascular epiphytes were sampled in the understorey across 141 plots within 23 Andean forests in the eastern Colombian cordillera We focused on the community‐level responses (species richness and total abundance) of the hyperdiverse vascular epiphyte communities using generalized linear mixed models to quantify the direction and the spatial extent of the scale‐of‐effects. Results: Habitat loss and edge effects act at fine spatial extents (scale‐of‐effects = 200 m), predicting low species richness and abundance across groups. Likewise, fragmentation negatively impacts communities, but operates at larger spatial extents (scale‐of‐effects = 2000–2400 m radius). The detection of these effects is contingent upon the spatial extent and specific landscape processes involved. Models of habitat loss within a spatial extent of 800–1500 m (large confidence intervals), fragmentation below 300 m, and edge effects above 800 m show weak statistical support (marginal r2 = 0.02–0.1). Thus, the impacts of these landscape processes may be overlooked if studied at inadequate spatial extents. Main Conclusions: We showed that habitat loss, fragmentation and edge effects all play a negative role on understorey epiphytic communities, but their detectability is scale dependant. The scale‐of‐effects can assist landscape designs that are beneficial for epiphytic communities, by preserving forest cover, and reducing fragmentation and exposure to edge effects at small scales (200–300 m). Conversely, landscape‐scale actions directed at reducing habitat loss and fragmentation function at larger spatial extents (>2000 m). Selecting a priori or inadequate spatial extents of analysis can obscure the detectability of landscape processes. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Palms provide vital plant resources and ecosystem services to people across the tropics. To improve conservation guidance, a "health check" of palms in two highly threatened biodiversity hotspots in Colombia and Ecuador was undertaken. Palms are very diverse in these regions, but over one third are threatened with extinction now, especially among endemic species. Widespread and useful palms are also under intense human pressure and need to be prioritized in terms of sustainable management practices. Given the importance of palms for humans, inclusive conservation actions should be continued in both countries in order to safeguard this resource. Summary: Palms provide central plant resources to societies in the tropics, especially in the Global South. The western Pacific and Andean regions of Colombia and Ecuador host two hotspots of biodiversity. To prioritize conservation policies towards palms, we undertook a conservation assessment of species in the region.We compiled a taxonomically verified database of specimens collected in both hotspots. We inferred preliminary conservation assessments using International Union for Conservation of Nature (IUCN) Criteria B. In addition, we evaluated the level of exposure of palms to human use and population density using the anthrome concept.We documented 144 native palm species in 33 genera occurring in both hotspots of Colombia and Ecuador. Of these, 55 are endemic to this region. We recorded 133 species for Colombia, 43 endemic, and 71 species for Ecuador, 9 endemic. A third of all palm species in the region are potentially threatened with extinction (50/144) and 12 as preliminary Critically Endangered. Aiphanes and Geonoma have the highest number of threatened species. In total, 60% of palm specimens were collected in the "low human impact" anthrome type. In contrast, 41% of specimens occur in high human density areas.The two hotspots of biodiversity in Colombia and Ecuador are very diverse in palms. However, we show that this diversity is under threat and is predominantly found in areas impacted by human activities. Extinction risk is highest in endemic species in both countries. Widespread and useful palm species also face threats linked to overexploitation or habitat loss. Inclusive conservation measures should be designed to conserve, together with communities, this plant resource. [ABSTRACT FROM AUTHOR]

Cryptic biodiversity continues to be revealed worldwide, even in apparently well-known groups such as carnivorans. The Neotropical Otter (Lontra longicaudis) presents shape variation in its nose pad, a character that has been used to differentiate species in this group. Based on this, 3 subspecies are recognized: L. l. annectens (Mexico, Central America, and South America west of the Andes), L. l. enudris (Amazon and Orinoco basins), and L. l. longicaudis (Paraná basin and remaining distribution). Previous studies partially supported their distinctness based on mitochondrial DNA markers, morphometrics, and ecological niche modeling. We analyzed genome-wide nuclear markers (ultraconserved elements) of 29 L. longicaudis individuals across the species' range to assess its population structure. Phylogenomic analysis recovered L. longicaudis as paraphyletic with robust support, with 1 clade comprising samples from Mexico and Colombia (trans-Andean populations) and another encompassing the remaining samples (cis-Andean populations), which grouped with 2 other South American species, L. felina and L. provocax. Principal component and admixture analyses strongly differentiated the 2 main L. longicaudis groups, and distinguished the Amazonian individuals from the remaining cis-Andean samples. Our results support the recognition of trans-Andean populations of L. longicaudis as a distinct otter species, which should be recognized as Lontra annectens. [ABSTRACT FROM AUTHOR]

Climatic classification is essential for evaluating climate parameters that allow sustainable urban planning and resource management in countries with difficult access to meteorological information. Clustering methods are on trend to identify climate zoning; however, for microclimate, it is necessary to apply a double clustering technique to reduce the variability from former clusters. This research raised a climate classification of an emerging country, Colombia, using climatological models based on freely available satellite image data. A double clustering approach was applied, including climatological, geographic, and topographic patterns. The research was divided into four stages, covering the collection and selection of climatic and geographic data, and multivariate statistical analysis including principal components analysis (PCA) and agglomerative hierarchical clustering (HAC). The meteorological data were from reliable sources from the Center for Hydrometeorology and Remote Sensing (CHRS) and the National Renewable Energy Laboratory (NREL). The results showed that a total of 17 microclimates distributed across the country were identified, each characterized by a different threshold of the climatic and geographic factors evaluated. This subdivision provided a detailed understanding of local climatic conditions, especially in the mountain chains of the Andes. [ABSTRACT FROM AUTHOR]

Hard ticks of the genus Ixodes are one of the most diverse groups in the Neotropical region, but some species are known only from historical records. In Colombia and Venezuela, Ixodes montoyanus is known from records obtained more than 50 years ago. In this study, we performed morphological and molecular evaluations of immature and adult stages of I. montoyanus collected from Pudu (Pudella) mephistophiles, in the municipality of Puracé, Cauca, in the Andean region of Colombia. The results include the first morphological evaluations of larvae, nymphs, females and males of I. montoyanus, confirming each of these stages with their respective sequences of a fragment of the mitochondrial 16S rRNA gene, and nymphs and females with a fragment of the mitochondrial cox1 gene. These results represent the first molecular information of I. montoyanus from Colombia, allowing differentiation of this species from others within Ixodes distributed in the country. The data generated consolidate valuable information for the genus Ixodes, which plays an important role in pathogen transmission. The information is also key to addressing the controversy regarding the identification, validity and distribution of various species within the genus. [ABSTRACT FROM AUTHOR]

Satellite-based monitoring provides insights on synergies and trade-offs between energy production and land use and land cover (LULC) changes (LULCC) around hydropower dams. Using Landsat data, we mapped LULCC related to hydropower expansion to understand change dynamics of cash crop production in the Magdalena River basin (Colombian Andes). We leveraged secondary map products and an active learning routine to produce thematically detailed LULC maps, for 2009, 2015, and 2020, including key cash crops (rice and oil palm). Our area-adjusted accuracy assessment revealed high overall and class-specific user's and producer's accuracies, exceeding 80% for oil palm, rice, non-agricultural vegetation, wetlands, and grasslands, and accuracies of ~60% for other temporary and permanent crops. We identified substantial losses of rice (10,6%) and grasslands (25,9%) in El Quimbo due to reservoir flooding. For Hidrosogamoso, there was a loss of wetlands downstream. Our products provide the basis for balancing social, economic, and environmental trade-offs related to conflicting land uses. [ABSTRACT FROM AUTHOR]

Paleomagnetic results obtained from 38 Pliocene—Pleistocene volcanic flows from the Knot of the Pastos and surroundings of Puracé volcano and Popayán (southwestern Colombia) are presented. Using stringent quality criteria and excluding sites that classify as representatives of transitional states of Earth's field, a selected group of 27 sites (16 with normal polarity and 11 with reversed polarity) was obtained with a mean direction (Dec = 357.8°, Inc = 6.4°, α95 = 7.5° and κ = 15) that coincides with the geocentric axial dipole field (GAD: Dec = 0o, Inc = 3.2o) and, unlike similar studies at similar latitudes, does not coincide with the GAD plus a 5% axial quadrupolar component (Dec = 0°, Inc = −1.08°). However, when serial correlation (SC) among several sites with high inclination anomalies is taken into consideration, the mean direction of two resulting groups of sites shows greater consistency with a field that includes a quadrupolar component. It is interpreted that the sites treated for SC record states of the field similar to today's field in the area of study, which is being affected by the South Atlantic Anomaly. Plain Language Summary: The only way to study Earth's magnetic field in the geologic past from experimental data is by studying the magnetization of rocks that record Earth's field in a way comparable to the way compasses point close to the geographic north. Earth's magnetic field changes are significant in relatively short time‐scales like years or centuries. In this study the paleomagnetic directions recorded in volcanic products from extinct volcanoes of the Colombian Andes were obtained. Most of the volcanic flows record paleomagnetic directions consistent with the ones obtained from previous studies, which in general differ from the present magnetic directions in the area by being less inclined downwards. However, some of the volcanic flows did record paleomagnetic directions that are similar to the present magnetic directions in the area, which have been linked to an ample low magnetic intensity area in the Atlantic Ocean called the South Atlantic Anomaly. So, as it has been pointed out in other studies, it is possible that this anomaly has acted recurrently during the geologic past. Key Points: The mean paleomagnetic direction among the selected sites from Colombia shows consistency with a geocentric axial dipole (GAD) fieldConsistency with a GAD field with a 5% quadrupolar component is obtained when serial correlation is appliedSerially correlated sites are probably affected by the South Atlantic Anomaly, in a way similar to the present field in the study area [ABSTRACT FROM AUTHOR]

Aim: Schizomids are one of the less-known arachnid groups in terms of their natural history and ecology. However, due to their remarkable short-range endemic distribution, they may be vulnerable to climate change and habitat loss. In Colombia, although the national IUCN red list of threatened invertebrates has categorized species of schizomids as vulnerable (VU), this assessment was based on expert criteria. Therefore, information about the ecology of schizomids is critical for a more accurate reassessment of their conservation status. In this study, we describe the habitat of two species of Surazomus in endangered Andean tropical forests of Colombia after a sampling effort of 15.12 m2 (n = 168 soil samples) and the collection of 6999 soil fauna individuals from the samples. We analyzed soil fauna communities associated with schizomids as well as different forest and environmental variables from permanent plots installed a decade ago in the Sabana de Bogotá region. Detailed information on climate, plant communities, and forest structure was obtained from these plots. Thus, we provide the first comprehensive habitat description of schizomids including both above- and belowground compartments. We found that each species lives in specific habitats with different soil fauna communities, suggesting a potential association between geographical fidelity and habitat conditions. This result could indicate that schizomids are highly sensitive to dramatic environmental changes, such as those experienced in the Andean region of Colombia. Implications for insect conservation: Our study is valuable for the future reassessment of the conservation status of schizomids in the country, particularly considering that the previous categorization was based on expert criteria. Since habitat conditions and soil fauna communities are species-specific, schizomids could be disproportionately vulnerable to climate change and human disturbances in the Colombian Andes. [ABSTRACT FROM AUTHOR]

In this paper we explore what campesino [peasant] livelihoods in the rural Andean mountains of Colombia offer to understandings of more-than-human co-existence and care. For, while new conservation paradigms promise to transform economic and social horizons, being "paramuno" [resident of the "paramo," or high moorlands] in the small community of Monquentiva is already characterized by becoming-with-other-beings-and-practices; a disposition toward incorporation of elements that are at-hand, and an ethics of care toward other beings in the landscape. We draw on ethnographic data to present this case study, emphasizing the forms of social organization and persistence that have enabled the emergence of economically and ecologically sustainable livelihoods. We explore these processes in terms of what we call world-making practices, showing how relationships with Indigeneity and collectivity are being renegotiated, and arguing for modes of conservation that engage with existing forms of peasant innovation. [ABSTRACT FROM AUTHOR]

The Complejo Volcánico Doña Juana – Cascabel National Natural Park is located between the departments of Cauca and Nariño in the southern Andean Region of Colombia. Due to the country's social challenges and the difficult access to the Doña Juana – Cascabel National Natural Park the biological knowledge concerning groups such as mammals, is based on studies prior to the park's declaration, reports from park rangers and residents. Between October 2017 and February 2018, eight trail cameras were set up in the Doña Juana – Cascabel National Natural Park and its buffer zone. We reviewed the information captured in these cameras and identified eight mammal species, three of which are new reports for the park. In total, 24 species were reported, including charismatic Andean species such as the spectacled bear (Tremarctos ornatus), and the Andean tapir (Tapirus pinchaque). The mammal diversity documented for the park is low (24 species) compared to other Andean areas. Further field work is necessary to complete the species inventories. Nevertheless, this research, to our knowledge is the first effort to study the medium and large mammals of the Doña Juana – Cascabel National Natural Park since its establishment in 2008. [ABSTRACT FROM AUTHOR]

Examining the efficacy of current assessment methodologies for forest conservation and restoration initiatives to align with global and national agendas to combat deforestation and facilitate restoration efforts is necessary to identify efficient and robust approaches. The objective of this study is to understand forest dynamics (1996–2021) and assess restoration implementations at the Urra's supplying basin hydroelectric reservoir in Colombia. The processing approach integrates optical and radar Earth Observation (EO) data from Sentinel-2 and Landsat for forest mapping and multi-temporal forest change assessment (1996–2021), and a Sentinel-1 backscatter time-series analysis is conducted to assess the state of forest restoration implementations. The processing chain was scaled in a cloud-based environment using the Nebari and SEPPO software and the Python language. The results demonstrate an overall substantial decrease in forested areas in the 1996–2000 period (37,763 ha). An accuracy assessment of multi-temporal forest change maps showed a high precision in detecting deforestation events, while improvements are necessary for accurately representing non-forested areas. The forest restoration assessment suggests that the majority of the 270 evaluated plots are in the intermediate growth state (82.96%) compared to the reference data. This study underscores the need for robust and continuous monitoring systems that integrate ground truth data with EO techniques for enhanced accuracy and effectiveness in forest restoration and conservation endeavors. [ABSTRACT FROM AUTHOR]

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Enhanced anthropogenic climatic variability challenges small farmers. In the Sumapaz páramo (Colombia), higher irregularity in precipitation and temperature reduces the quality of pasture and cattle health. Data from surveys, semi-structured interviews, and focus groups were analyzed to understand livestock farmers' responses to the impacts of climatic variability. To estimate the communities' resilience in the páramo, we used the capitals framework, the Baseline Resilience Indicator for Communities (BRIC), and cluster analysis. The responses of most households aim to reduce the impacts of climatic variability on the production system, chiefly intensifying practices such as the rotation of paddocks, livelihood diversification, purchase of grass, and buying and selling livestock. Interestingly, farmers did not recognize the value of the types of capital for responding to climatic variability. Results showed that the use of available physical, social, and economic capitals render the farming system resilient. Our probit model estimated that economic and human capitals are the largest and most significant contributors to communities' capacity to respond to climatic variability. However, pre-existing non-climatic vulnerabilities are also important. For example, poverty hinders farmers from using their income in response to climatic variability. The place-based measurements used in this research are easily understood and applicable by local policy makers to address increasing climate variability. [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]

The occurrence and types of ophiolites in the Central Cordillera of the Colombian Andes have not been identified in terms of their tectonic settings and geochemical features. Therefore, the study of the tectonic setting and subduction zones in the ophiolites' magmatic evolution becomes a significant issue. The Ginebra Ophiolitic Complex (GOC) is located on the western flank of the Central Cordillera in the Valle del Cauca Department, southwest of Colombia, assigned to the Lower Cretaceous period, as indicated by the contact of the GOC with the Buga Batholith. The GOC is formed by three main lithologies: amphibolite, gabbro, and ultramafic rocks (pyroxenite and peridotite), according to Ossa (2007). The rocks in the Puente Piedra section, located in the northeast of Ginebra municipality, are part of the gabbroic cumulates within the ophiolitic sequence. This sequence comprises interspersed layers of gabbroic cumulates, gabbrodiorites, and diorites; interpreted as a result of crystal accumulation and fractional crystallization processes. The mafic rocks of the GOC are sub-alkaline and correspond to the low potassium (K2O wt% 0.03-0.06) tholeiitic series. Geochemically, they have SiO2 wt% ranging from 49 to 61 and an aluminum oxide saturation index of approximately -0.4 and -0.8, indicating a metaluminous type. The geochemistry of the studied rocks from Puente Piedra section indicates that the GOC formed through fractional crystallization and accumulation processes from a single magma source. Cluster analysis, used to compare the geochemistry of GOC rocks and the Amaime Complex basalts, suggests a similar magma source, possibly linked to multiple recharge events that underwent fractional crystallization, melt extraction, and accumulation processes. The geochemical parameters are indicative of a suprasubduction zone ophiolite, characterized by a low potassium tholeiitic series affinity, TiO2 values typically <1.2 wt%, Th enrichment typical of subduction zones, high Pb content, and low values of Ti, Y, Yb, Ta, Nb, Zr, and Hf. [ABSTRACT FROM AUTHOR]

Knowledge of reproduction in wild Andean bears (Tremarctos ornatus) is scarce. Here we provide novel information about litter size, birth timings, courtship and multi-generational groups in a population in the Chingaza massif in Colombia. Pregnant females, mothers with cubs, estimated birth times, and litter size were registered through camera trapping of a population at the Chingaza massif (Colombia) between 2011 and 2016. A total of 34 independent records of reproductive female bears were obtained. Twenty-eight (28) different reproductive females were recognized by external key features. Six different females were recorded only pregnant, two others were recorded pregnant and later with cubs, and 20 others were recorded only with cubs. In total, 29 cubs were recorded in 22 litters, with a mean litter size of 1.27 (SD = 0.45): 16 litters with one cub, 5 with 2 cubs, and 1 with 2 cubs + a big cub from a previous litter (>1 year). The highest records of mothers with little cubs were obtained for the low rain season in December, January, and February, full of dry-season-fruiting Ericaceae shrubs. Likewise, the highest estimated births were obtained during the rainy time in June. Multi-generational groups and the courtship behaviors are reported for the first time in Colombia. [ABSTRACT FROM AUTHOR]

We present a reconstruction of the physicochemical conditions of melts in the Pleistocene storage and plumbing system of the Doña Juana Volcanic Complex (SW Colombia): a poorly known, potentially active polygenetic volcano of dacitic composition comprising four major edifices and showing periods of long quiescence. Compositional data for plagioclase, amphibole, pyroxene, and Fe-Ti oxides were combined with new and existing whole-rock data from representative eruptive products, allowing for the implementation of equilibrium tests and geothermobarometry calculations within an established stratigraphic, petrographic, and geochronological framework. Textural and geochemical variabilities of all mineral phases suggest the existence of a trans-crustal magmatic system feeding the Pleistocene eruptions of Doña Juana, and cyclic rejuvenation of a crystal mush following each volcano edifice collapse. The assemblage of different crystal cargos before magma recharge and final eruption is attested by (i) the coexistence of equilibrium and disequilibrium textures and variable compositions in crystals of all studied species, (ii) felsic cores in antecrysts, (iii) mafic overgrowth rims, and (iv) significantly less differentiated microcrysts relative to the composition of meso- and macrocrysts. By integrating multiple mineral-only and mineral-liquid geothermobarometers, after careful textural analyses, we estimate the intensive parameters of the mush–melt interaction zone of the plumbing system in the middle crust, providing a preliminary view of the architecture of a trans-crustal magmatic system in a complex tectonic setting at a previously understudied area of the north-Andean volcanic zone. [ABSTRACT FROM AUTHOR]

The genus Rhinella (Bufonidae) comprises 92 species of Neotropical toads. In Colombia, Rhinella is represented by 22 recognized species, of which nine belong to the Rhinella festae group. Over the past decade, there has been increasing evidence of cryptic diversity within this group, particularly in the context of Andean forms. Specimens of Rhinella collected in high Andean forests on both slopes of the Central Cordillera in Colombia belong to an undescribed species, Rhinella kumanday sp. nov. Genetic analyses using the mitochondrial 16S rRNA gene indicated that the individuals belong to the festae species group. However, they can be distinguished from other closely related species such as Rhinella paraguas and Rhinella tenrec by a combination of morphological traits including the presence of tarsal fold, a moderate body size, and substantial genetic divergence in the 16S rRNA gene (> 5%). Through this integrative approach, the specimens from the Central Cordillera of Colombia are considered an evolutionary divergent lineage that is sister to R. paraguas, and described as a new species. Rhinella kumanday sp. nov. is restricted to the Central Cordillera of Colombia inhabiting both slopes in the departments of Caldas and Tolima, in an elevational range between 2420 and 3758 m. With the recognition of this new species, the genus Rhinella now comprises 93 species with 23 of them found in Colombia, and ten species endemic to the country. [ABSTRACT FROM AUTHOR]

The harlequin toads (Bufonidae, Atelopus) from the Cordillera Occidental of Colombia are poorly understood, with several species being known only from few specimens and a single locality. Material from the Yotoco area, Departamento Valle del Cauca, has been addressed in previous studies and was allocated ambiguously to different available names. We here describe the Yotoco Atelopus as a species new to science as it is readily distinguished from all congenerics by a combination of morphological characters (i.e., snout profile, cranial crests, skin texture, pattern and coloration). In addition, we comment on the taxonomy of three Atelopus populations from the Cordillera Occidental and the Cordillera Central of Colombia; two of them we tentatively assign to A. nicefori and A. sonsonensis, respectively. The third one remains of unclear status. The need for further examination of the harlequin toads from the Andes of Colombia in an integrative taxonomic framework is emphasized. [ABSTRACT FROM AUTHOR]

Northern Andes Mountains exhibit high elevational fluctuation in thermal conditions for ectotherms. This fluctuating temperature limits the survival, growth, and dispersion of ectothermic organisms. Therefore, lizard species distributed on these mountain landscapes face strong temperature fluctuations. To test the potential effect of elevation, we characterized the critical maximum (CTmax) and minimum (CTmin) body temperature and time to reach CTmax (Tmax) and CTmin (Tmin) of individuals of Anolis tolimensis, an endemic species distributed on two cordilleras in the northern Andean system in Colombia. We collected individuals at four elevations (1,600, 1,900, 2,100, and 2,200 m asl) and measured their critical thermal limits under laboratory conditions. We also explored the role of sex and size on these physiological thermal variables. CTmax is similar among the elevations, but CTmin of the highest elevation (2,200 m asl) is the lowest (5.5±1.0°C) vs (2,100 m asl, 8.8±0.8°C; 1,900 m asl, 8.3±1°C; 1,600 m asl, 8.3±0.9°C). CTmax range is narrower (33–34.2°C) than CTmin (5.5–8.8°C), and thermal tolerance breadth (CTmin to CTmax values) is 28.7°C. Sex and body size may affect the thermal response, but the interaction varies with geography. Critical thermal limits are conservative (CTmax) or evolutionary labile (CTmin). Anolis tolimensis could deal with maximum environmental temperatures by thermoregulatory behavior or by an alternative strategy of increasing the time to reach the CTmax. Finally, extinction risk evaluation is needed to test the potential vulnerability of the population at the second-highest elevation. [ABSTRACT FROM AUTHOR]

The blueberry, a deciduous shrub in the Ericaceae family, is celebrated for its delightful flavor, sweetness, and abundance of anthocyanins and antioxidants, qualities that have garnered significant attention for their potential health benefits. Blueberries grown in diverse environments and exhibit varied anthocyanin profiles, often influenced by factors such as altitude and climate. Varietal groups worldwide have been bred and categorized based on their growth habits and specific cold requirements, particularly with southern highbush cultivars thriving in temperate climates, demonstrating tolerance to higher altitudes or cooler climates—a result of hybridizations involving various Vaccinium species. In the Colombian Andes, southern highbush blueberries thrive in unique high-altitude conditions, leading to exceptional quality due to the region's cool climate and specific soil characteristics. In this context, this study aimed to chemically characterize and differentiate three southern highbush blueberry cultivars (i.e., 'Biloxi,' 'Legacy' and 'Sharpblue') cultivated in a Colombian Andean plateau and compare them to three commercially available highbush blueberries. This comprehensive evaluation involved examining total phenols, flavonoids, anthocyanin content, and DPPH· free-radical scavenging capacity, as well as conducting anthocyanin-targeted profiling via HPLC-DAD-HRMS. Through supervised multivariate analyses such as sPLS-DA, this study delved into the pattern recognition of those anthocyanins that could potentially serve as markers for quality and cultivar-related chemical trait determination. These findings locate blueberry-derived anthocyanins in a metabolic context and afford some insights into southern highbush blueberry cultivar differentiation to be used for further purposes. [ABSTRACT FROM AUTHOR]

The increasing interest in tropical fruits has been observed worldwide, driven by their desirable sensory and nutritional characteristics. Lulo (Solanum quitoense L.), an exotic and native South American fruit, is predominantly used in beverage production and commercially marketed in Colombia and Ecuador. However, the perishable nature presents challenges for their commercialization to market. This has prompted food researchers to be interested in developing new Lulo-based products, that can have an agro-industrial impact in the countries of origin. Lately, a growing number of studies have aimed to uncover the nutritional and bioactive properties of Lulo. These studies have revealed that the fruit is rich in vitamin C, chlorogenic acids, phenolic compounds, and bioactive amines, making it an attractive raw material for the agri-food and pharmaceutical industries. This review summarizes the current understanding of the properties of Solanum quitoense L., including its physicochemical, nutritional, and bioactive properties. The fruit's high concentration of beneficial compounds has increased interest from industries and presents new opportunities for economic growth in the countries where it is grown. The growing demand for natural products underscores the need for further research on Lulo's potential applications and benefits, which could result in the development of new and economically viable products. [ABSTRACT FROM AUTHOR]

The Nazca-South America subduction zone in Ecuador is characterized by a complicated along-strike geometry as the slab transitions from flat slab subduction in the south, with the Peruvian flat slab, to what has been characterized as 'normal' dipping subduction beneath central Ecuador. Plate convergence additionally changes south to north as the trench takes on a convex shape. Highly heterogeneous bathymetry at the trench, including the aseismic oceanic Carnegie Ridge (CR), and sparse intermediate-depth seismicity has led many to speculate about the behaviour of the downgoing plate at depth. In this study, we present a finite-frequency teleseismic P -wave tomography model of the northern Andes beneath Ecuador and Colombia from 90 to 1200 km depth. Our model builds on prior tomography models in South America by adding relative traveltime residuals recorded at stations in Ecuador. The complete data set is comprised of 114 096 relative traveltime residuals from 1133 stations across South America, with the added data serving to refine the morphology of the Nazca slab in the mantle beneath the northern Andes. Our tomography model shows a Nazca slab with a fragmented along-strike geometry and the first teleseismic images of several proposed slab tears in this region. At the northern edge of the Peruvian flat slab in southern Ecuador, we image a shallow tear at 95–200 km depth that appears to connect mantle flow from beneath the flat slab to the Ecuadorian Arc. Beneath central Ecuador at the latitudes of the CR, the Nazca slab is continuous into the lower mantle. Beneath southern Colombia, the Malpelo Tear breaks the Nazca slab below ∼200 km depth. [ABSTRACT FROM AUTHOR]

Aim: Andean forests are a global biodiversity hotspot. They harbour many species living within narrow climate ranges and a high functional diversity of trees. It remains still unclear how such hotspots respond to climatic changes over time. We investigated whether Andean forests are changing their functional composition over time along an elevational gradient by assessing changes in species composition, abundance and functional traits. Location: An elevational gradient in Colombia's northern Andes. Time Period: Species composition changes were studied two to four times from 2006 to 2017, and functional composition from 2016 to 2017. Major Taxa Studied: A total of 1104 tropical tree species with in situ traits characterization. Methods: We used seven morphological leaf traits and wood density values to analyse the functional trait dynamic over 10 years along an elevational gradient. By analysing changes in species composition, abundance and trait representation, we inferred the magnitude and direction of changes in functional composition. Then, we assessed if the functional change was related to climate change and demography. Results: With increased minimum temperature and vapour‐pressure deficit, we found a decrease over time in mean values for leaf area and specific leaf area and increases in leaf thickness and leaf dry matter content. Long‐term temperature increases are smaller with increasing elevation, but the magnitude of trait changes is greater than in lowlands. Main Conclusions: The functional composition is changing towards more conservative strategies over time across the elevation gradient, with the strongest changes observed at the highest elevations. This pattern is explained by the change in species turnover within communities due to higher recruitment rates of species with high leaf dry matter content values and low leaf area values. These shifts may be related to communities' responses to higher evapotranspiration demand and thermal stress, mainly at higher elevations. [ABSTRACT FROM AUTHOR]

Bird assemblages are increasingly threatened by anthropogenic factors, leading to growing concern about their key role in natural ecosystems. This has led to the creation of conservation programs, however, one of the greatest obstacles to this end is the lack of updated information on the species distribution and taxonomic status. In Colombia, which is recognized as the country with the greatest diversity of birds in the world, conservation efforts are often constrained by the lack of baseline information or outdated data in different regions. To contribute to the knowledge of the regional avifauna, we present an updated checklist for birds of the municipality of Salamina (Caldas), based on published information and field records. We also listed resident, threatened, and endemic species. The checklist includes 279 bird species, 23 of which are migratory, three endemics to Colombia, six are categorized as Near Threatened, and two as Vulnerable (following the IUCN criteria). We propose this updated checklist as baseline information, which can be used in future ecological and management studies of species under conservation priority [ABSTRACT FROM AUTHOR]

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas 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.)

Global Precipitation Measurement satellite and ERA5 reanalysis data are used to study the 4D (latitude, longitude, altitude, time) distribution of rainfall intensity and latent heating fields over the rainiest region on Earth, located over western Colombia and the far eastern equatorial Pacific. The annual and interannual variability and the location of both variables' maxima are identified, and their spatiotemporal correlations are quantified. Static analyses of the winds show that the colder Choco low‐level jet (LLJ) and the warmer Caribbean‐Panama jet form a tropical frontal system. Dynamic analyses of 3D streamlines reveal that the Choco LLJ is at the core of a quasi‐permanent mini‐Hadley cell over the Pacific, with sinking motion between 6°S‐Equator and rising motion at 5°N–8°N, comprised between 1,000 and 700 hPa. Such vortex dynamics enhances the convergence of the northerly winds and the Panama jet, and exacerbates deep convection in association with the orographic lifting over the Colombian Andes. The large‐scale branches of that flow illuminate the shape and dynamics of the Walker cell over tropical South America. Correlation analyses illustrate the connections between rainfall and 3D winds as moisture transport mechanisms. Correlation and singular value decomposition analyses suggest that oceanic (continental) evaporation is associated with rainfall during the drier (wetter) season, and the importance of high‐levels temperatures and vertical integrals of diverse thermal and energy variables on rainfall bolster the view that the condensational heating is strongly coupled with the moisture transport flow and the convective ascent required to explain such extraordinary amounts of rainfall. Plain Language Summary: The rainiest region on Earth is located over western Colombia and the far eastern equatorial Pacific. It constitutes an exceptional geographical setting to study the mechanisms controlling extreme tropical rainfall. We investigate the spatiotemporal distribution of rainfall and atmospheric heating resulting from condensation at monthly, annual, and interannual timescales, using satellite data. Correlations and locations (latitude, longitude, height) of both variables' maxima are identified. We investigate the main physical mechanisms behind such a record‐breaking rainfall region, finding that: (a) the strong ascent of moist air is driven by a tropical warm/cold frontal system formed by the colder Choco low‐level jet (LLJ) and the warmer Panama jet, enhanced by the orography of the Andes; (b) a dynamic analysis reveals that the Choco LLJ constitutes the inner vortex of a mini‐Hadley cell acting over the Pacific ocean with sinking motion around 6°S‐Equator and rising motion at 5°N–8°N, restricted to the lower atmospheric levels; (c) the Andes contribute to shape the dynamics of the Walker cell over north tropical South America; (d) the upward winds and vertical atmospheric accumulations of diverse thermal and energy variables are strongly associated with rainfall; and (e) evapotranspiration also plays an important role in driving regional precipitation. Key Points: Annual and interannual variability, maxima locations and space‐time correlations of 3D rainfall and latent heating rates are estimatedA frontal system formed by the Panama/Choco jets and a mini‐Hadley cell (engulfing the Choco jet) drive and enhance deep moist convectionVertical winds, evapotranspiration and thermal variables correlate with rainfall. The Andes add orographic lifting and shape the Walker cell [ABSTRACT FROM AUTHOR]

People making a living in rural Antioquia, Colombia, find themselves in a double bind: they require a healthy environment to farm and grow food, but many turn to artisanal and small-scale gold mining (ASGM) to supplement their incomes. The significant environmental harms associated with ASGM – from mercury and other heavy-metal contamination to deforestation and habitat loss – have led to both academic and popular discourse treating ASGM as an environmental problem to be understood and remedied scientifically. Our research in the small town of Andes (Antioquia region in Colombia) investigated how local residents themselves understood "pollution." Drawing on a literature review, archival research, site visits, and interviews with experts and local residents, we show that rural people understood pollution as emergent from complex webs of relationships and longer histories of government neglect. Exploring how people made sense of harm and expressed care builds on research in STS that demonstrates both the potentials and pitfalls for scientific concepts and tools to understand and intervene in compromised environments. [ABSTRACT FROM AUTHOR]

Three new species of Stenospermation from Central Andes in Colombia are described: Stenospermation albifolium Castaño-Rubiano, S. melidae Castaño-Rubiano & Sierra-Giraldo and S. selvaflorensis Castaño-Rubiano, L. Ibañez & A. Zuluaga. The species are distributed in the eastern zone of Caldas and Antioquia departments, in Natural National Park Selva de Florencia, and in forest near to corregimiento de Berlin (Samaná-Caldas), at elevations between 653 and 1700 m a.s.l., as well as in Carmen del Vivoral (Antioquia) at 1087 m a.s.l. The new species are compared with the morphologically closest taxa and comments are made on their phenology. [ABSTRACT FROM AUTHOR]

A new species of Aiouea (Lauraceae) from the Colombian Andes is described and illustrated. Aiouea chicaque is distinguished by the following combination of characters: elliptic leaves with cuneate to attenuate bases, pinnate venation, glabrous, without domatia, externally glabrous flowers with stamens of whorls I and II with four locules, whorl III with two locules, and fruits with persistent tepals in the cupule. According to IUCN criteria, the new species is given a preliminary threat assessment as Vulnerable (VU) based on its reduced area of occupancy and the small number of localities where it is found. Additionally, two species of Ocotea and one of Andea, previously known from the Andes of Ecuador, are here recorded for the first time for the flora of Colombia: O. fistulosa, O. pautensis and A. homeieri. [ABSTRACT FROM AUTHOR]

Internal insect microbial communities, that is microbe taxa that live within an organism, play important roles in digestion, protection from pathogens, and fitness of their insect hosts. Recent expansion of research in this field has highlighted the importance of endosymbiotic communities to their hosts and elucidated microbial community patterns based on host life history. Here, we document the bacterial microbiome of two species of the butterfly genus Heliconius (Nymphalidae), each from two fragmented populations, by sequencing the V4 region of the 16S rRNA gene. We used 14 individual adult butterflies from two species, Heliconius cydno (n = 10) and H. clysonymus (n = 4), from two forest reserves in the Central Colombian Andes. Commensalibacter (Acetobacteraceae) was the most common bacterial genus across all samples, although relative abundance varied across groups. Notably, we also observed the bacterial genera Spiroplasma (Spiroplasmataceae) and Wolbachia (Ehrlichiaceae). While we did not find distinct spatial or species-level patterns in bacterial composition of microbiomes, we did find disparate bacterial diversity across the two butterfly species, with H. cydno harboring higher diversity than H. clysonymus. The microbiome composition of the two butterfly species did not differ, but that of H. cydno was distinct from the microbiome composition of environmental/butterfly trap bait samples. These findings contribute to the documented diversity of insect microbiomes and inform future experimental and sampling efforts. [ABSTRACT FROM AUTHOR]

Accelerated rates of urbanization negatively impact natural habitats and biodiversity. Studies of the effects of urbanization on fauna have emphasized taxonomic diversity, but this does not necessarily reflect effects on the evolutionary history of assemblages. Here, we study how urbanization influences phylogenetic diversity (PD) of bird assemblages in a small–medium city in the Central Andes of Colombia. Between 2016 and 2017, we performed bird surveys in 76 urban cells and 23 rural cells around the city. Then, we measured habitat characteristics (e.g. anthropogenic noise level, impervious and forested area) in sampled cells. PD of birds was between 1.37–1.42 MY higher in the rural than in the urban habitat. Within the urban habitat, the PD of birds reduces as impervious area and noise levels increase, while in the urban cells with most forested areas reach the highest PD values. Most of these differences and relationships disappear when we performed similar analysis controlling for differences in species richness. A low turnover of PD between assemblages of birds recorded inside Armenia and its less urbanized surroundings suggest green areas in the study area could mitigate the effects of urbanization in native fauna, and ameliorate connectivity between urban cells. [ABSTRACT FROM AUTHOR]

Insects that inhabit high‐altitude ecosystems are an ecologically specialized group whose distribution is restricted by the presence of biogeographical barriers. These biogeographical constraints are thought to mould the shape of some insect structures because of environmental pressures that may produce better adaptations in extreme environments. We evaluated the potential distribution of Homocopris achamas and Uroxys coarctatus in two life regions (the Andean region and the Páramo region) found in the Andes of Colombia, and we determined if there were differences in their morphology along an elevational gradient. To determine the potential distribution of the species, we obtained geographical data through the systematic search of databases and entomological collections that we modelled under the maximum entropy model. We then evaluated the morphological variations by measuring geometric structures such as the clypeus (MC), the eye (ME) and the area of the anterior tibia (TA). We found that both species along the entire gradient exhibited the following characteristics: H. achamas was dominant in the Páramo region and showed two population nuclei separated by a wide biogeographic barrier, while U. coarctatus was more dominant in the Andean region and was distributed only in the northern Andes. Both were always linked to ecosystems with open vegetation that was both natural or intervened. H. achamas did not show changes in the shape of the structures while U. coarctatus showed differences in MC and ME. We suggested that livestock activity could act as an engine for breaking down biogeographical barriers allowing the distribution of a species to expand, and with this distributional expansion changes in the morphological structures of some species linked to their phenotypic plasticity could be promoted. [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]

High-elevation cushion peatlands are typical ecosystems of the Andes above 4000 m of altitude, with an important role in hydrology and global carbon sequestration. In Tropical Andean context, grazing livestock is one of the main threats to cushion peatlands, altering the vegetation and the storage carbon function. The aim of this research is to understand how grazing influences cushion peatland functioning by identifying ecological thresholds for carbon balance process. The study was carried out in four Andean peatlands in the northern part of Colombian Andes during 2019–2020. We established 30 plots of 1 m2 where water table level, vegetation cover, and grazing disturbance were monitored. We also measured CO2 fluxes using an infrared gas analyzer connected to a closed static chamber, which registered net ecosystem exchange and respiration data. Considerable variation in the conservation status of Distichia muscoides cushions was found within the sampled peatlands, reflecting an heterogeneous signal of grazing disturbance that is evident at the plot-specific scale. Decreasing water table level was related with changes in dominant vegetation, from compact cushion species to grasses proliferation, exacerbating disturbance effects and carbon emissions. Mixed-effects logistic regression models showed a carbon balance shift, from CO2 sink to net emitter, in plots with high disturbance intensity and low D. muscoides cover. This study provides information for a better understanding of mountain peatlands functioning in the Tropical Andes and underlines the key role of D. muscoides cushions and the water table in carbon balance shift. [ABSTRACT FROM AUTHOR]

Wood density (WD) is a key functional trait related to ecological strategies and ecosystem carbon dynamics. Despite its importance, there is a considerable lack of information on WD in tropical Andean forests, particularly regarding its relationship with forest succession and ecosystem carbon cycling. Here, we quantified WD in 86 upper Andean tree and shrub species in central Colombia, with the aim of determining how WD changes with forest succession and how it is related to productivity. We hypothesized that WD will increase with succession because early successional forests will be colonized by acquisitive species, which typically have low WD, while the shaded understory of older forests should favor higher WD. We measured WD in 481 individuals from 27 shrub and 59 tree species, and quantified aboveground biomass (AGB), canopy height, net primary production (NPP) and species composition and abundance in 14, 400-m², permanent plots. Mean WD was 0.513 ± 0.114 (g/cm³), with a range between 0.068 and 0.718 (g/cm³). Shrubs had, on average, higher WD (0.552 ± 0.095 g/cm³) than trees (0.488 ± 0.104 g/cm³). Community weighted mean WD (CWMwd) decreased with succession (measured as mean canopy height, AGB, and basal area); CWMwd also decreased with aboveground NPP and stem growth. In contrast, the percentage of NPP attributed to litter and the percent of shrubs in plots increased with CWMwd. Thus, our hypothesis was not supported because early successional forests had higher CWMwd than late successional forests. This was related to a high proportion of shrubs (with high WD) early in succession, which could be a consequence of: 1) a low seed availability of trees due to intense land use in the landscape and/or 2) harsh abiotic conditions early in succession that filter out trees. Forest with high CWMwd had a high %NPP attributed to litter because they were dominated by shrubs, which gain little biomass in their trunks. Our findings highlight the links between WD, succession and carbon cycling (biomass and productivity) in this biodiversity hotspot. Thus, WD is an important trait that can be used to understand upper Andean forest recovery and improve forest restoration and management practices. [ABSTRACT FROM AUTHOR]

We newly report two populations of the orchid Sievekingia hirtzii in the Andean-Amazonian foothills of Caquetá, Colombia. Following the B criterion of the International Union for the Conservation of Nature, we propose the categorization of this species as Endangered, due to its small Area of Occupancy and Extent of Occurrence, the limited number of populations, and habitat fragmentation and degradation caused by the expansion of agriculture. Additionally, we propose actions for in situ and ex situ conservation of this orchid, including habitat protection and cultivation in botanical gardens. [ABSTRACT FROM AUTHOR]

Intense disputes between companies and the local population have led to new governance regimes, raising concerns about the hydropower business's sustainability, social instability, and violence in emerging economies. New approaches to these issues must go beyond a critical view to be more adaptative and result oriented. This paper explores how the hydropower business's sustainability influences governance regimes on the territory. A cross-case study is applied in the Samaná River basin in the Colombian Andes through a qualitative-quantitative mixed methodology to generate a grounded theory of sustainability and governance in hydropower territories. A qualitative approach was used to produce a framework about territorial factors based on 45 in-depth interviews. The quantitative approach was used as a machine-learning data compression and prediction method. It served as an additional test to extend and reshape the prediction power of the coding. The results suggested three territorial factors of hydropower business as drivers of governance regimes: (1) context variation, (2) the spatial configuration of governance, and (3) the importance of long-term stakeholder interactions. Implications of findings involve addressing power asymmetries and adapting the collaborative dynamics to the territory. This analysis validated a previous interpretative model and proposed sustainability and governance patterns useful in similar hydropower territories in emerging countries. [ABSTRACT FROM AUTHOR]

The common name of pampas cat includes a complex of small Neotropical felid species found in various habitats of South America. Recently several species of this complex were proposed, but there are few records in the northernmost distribution of the continent, and reports of the pampas cat's presence in Colombia have been ambiguous. Current northern limits of Leopardus garleppi are limited to the Andes of Ecuador. Here we present the northernmost record of the species, validating its presence in Colombia and review previous controversial records from the country. The new record is based on a road-killed specimen in a dry tropical forest ecosystem in the municipality of Mercaderes, Department of Cauca. Our morphological and genetic comparisons also shown that a previous record from Colombia supported by a single skin recently used to described a new species named Leopardus narinensis belong to Leopardus tigrinus. With the information compiled from new localities in Colombia and Ecuador, the known distribution range for L. garleppi is increased towards the northern part of South America into areas of Tropical Dry Forest. The distribution now includes 14 ecoregions from Colombia to Bolivia, and four in Colombia (Eastern Cordillera real montane forests, Northwestern Andean montane forests, Northern Andean paramo, and the Patía Valley dry forests), which correspond to similar ecosystems inhabited by the species in other Andean landscapes. The potential distribution hypothesis showed that the species has high suitability in large areas of southwestern Colombia (Nariño). With the recording of L. garleppi in Colombia, the number of extant felid species in the country has increased to seven. [ABSTRACT FROM AUTHOR]

Geodiversity, comprising both endogenous and exogenous geological processes, plays a crucial role in shaping the structure and functionality of natural systems, alongside its substantial impact on human well-being. However, the often-overlooked interconnection between geodiversity components limits our comprehension of geosystems. In the Chinchiná River Basin (CRB) in Colombia, located in the northern Andes in South America, we established criteria to differentiate geodiversity classes, calculated indices to understand the distribution of geological elements, and discussed systemic relationships. This comprehensive approach lays the foundation for a holistic comprehension of the territory's structure and functionality. Our findings revealed the convergence in an area of 1052 km2 of 10 rock types, 7 slope ranges, 13 landforms, 5 drainage density features, 610.4 km of faults with 9 kinematic tendencies, 5 soil orders, 5 climate types, a 3328 km surface drainage network with 7 hydrographic orders, 1 underground aquifer, 4 areas with lakes, 2 zones with glaciers, 27 polygenetic and monogenetic volcanoes, and several thermal springs. This discussion explores the implications of various methodologies used to establish the value of the general geodiversity index while also examining the relationships between abiotic elements and their distribution patterns. This forms a fundamental basis for understanding the geosystem services of the basin in terms of regulation, support, and provisioning processes, as well as the culture and knowledge derived from geodiversity. These conceptual elements are indispensable for enhancing the sustainability of a region that is susceptible to the impacts of climate change. Furthermore, they serve as the foundations for the objective's achievement, as set by the UNESCO Global Geopark project "Volcán del Ruiz", currently ongoing within the region. [ABSTRACT FROM AUTHOR]

The timing of breeding is a key component of the life history of birds. In the tropics, where avian diversity is higher and environmental variability is less predictable than in temperate latitudes, breeding phenology patterns are poorly understood, and many other life-history traits remain largely unstudied. We describe the nest, egg, juvenile plumage, and breeding phenology of a population of the grey-browed brushfinch (Arremon assimilis assimilis, Passerellidae) from the Eastern Andes of Colombia. We found a single bluish-white unmarked egg in a cup-shaped nest. We also examined the relationship between photoperiod and precipitation with breeding phenology by monitoring 44 territorial pairs between 2017 and 2018. Arremon assimilis has two breeding peaks associated with the onset of rainfall in prior months: the first peak extends from mid-May to September, and the second from November and December to January. We also update a recent review of breeding biology data in Arremon and discuss how life-history traits may have evolved in light of the relationships among sparrows in this genus. Our study, one of few analyses of the breeding biology of a population in a montane species from the Andes, highlights the importance of such studies to further comprehend the general mechanisms that shape the breeding biology of tropical birds. [ABSTRACT FROM AUTHOR]

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Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales 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 de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales 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.)