Rapid climate changes and the increasing presence of humans define the Holocene Epoch (11.6 calibrated kiloyears before present – hereafter kyr BP), when biological systems have faced the most recent and abrupt environmental changes. Understanding how biodiversity responds to extrinsic factors requires determining the effects of varying climatic conditions, changes in disturbance regimes, and increasing anthropogenic impacts. Despite being one center for biodiversity, the potential synergies of long-term anthropogenic and climate changes in shaping areas of high Andean biodiversity have yet to be explored fully. Here we present new pollen and charcoal records from the Pantano de Monquentiva (hereafter Monquentiva) on the highlands of the eastern flank of the Colombian Cordillera Oriental (CCO) to document relationships between climate, vegetation, and fire through the Holocene. We found compositional transitions at 8.7, 6.1, and 4.1 kyr BP at Monquentiva resulting from the interaction of climate, fire, and human occupation. Reduced moisture and temperature caused a compositional shift in Páramo vegetation from ca. 8.7 kyr BP. Fire activity was recorded throughout the Holocene and increased slightly during the Mid-Holocene when regional and local fire decoupling suggested human activities as the source of ignition. Mid-Holocene fires had a large effect on the vegetation composition at Monquentiva which recorded a rapid shift at ca. 6.8 kyr BP. Fire activity increased sharply from 4.1 kyr BP, promoting the reorganization of plant communities at 3.8 kyr BP. This shift in fire activity was likely related to more severe ENSO events and subsequently intensified by human activities after 3.8 kyr BP. Although high climatic sensitivity explains most Holocene vegetation changes in the eastern flank of the CCO, our study highlights the relevance of fire activity, uneven distribution of climatic variables, and human intervention to the composition of the vegetation we see today.

This study presents the first multi-proxy palaeoenvironmental and palaeoclimatic history for northern South America based on the palaeolimnological reconstruction of a pond located in a dry paramo at 3570 masl. During the Last Glacial Maximum (LGM), the study area was under glacial conditions, then during global events Heinrich Stadial 1 (HS1), Bølling-Allerød (BA), and the Younger Dryas (YD), the pond expanded, accumulation rates and proxies for erosion reached the highest values, indicative of humid conditions, with maxima in humidity during the BA and YD. Dry conditions and pond desiccation occurred in the Greenlandian-Northgrippian and by 6010 cal a BP the area was transformed into the mire of today. Comparisons with records from other sites in South America indicate that changes in humidity are most likely controlled by the Intertropical Convergence Zone, mainly during the glacial and postglacial, and by changes in the Pacific Ocean, more pronounced after the YD.

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Con el fin de determinar la calidad de la miel de Apis mellifera variedad scutellata, procedentes de las subregiones del Suroeste y Oriente Antioqueño, producidas durante los años 2013 y 2014, se realizó un estudio fIsicoquímico y palinológico de 18 muestras. El análisis fIsicoquímico reveló que todos los parámetros analizados se encontraban dentro de los valores establecidos por la normatividad Colombiana, con muy pocas excepciones. En general todas las mieles analizadas fueron de buena calidad y las variaciones en los parámetros analizados, fueron relacionadas con el origen botánico y geográfico de las mismas o errores en el proceso de manipulación. Desde el punto de vista palinológico se observó que la mayoría de mieles del Suroeste fueron uniflorales y las del oriente multiflorales; la riqueza total de polen de las muestras fue muy variable en ambas regiones, oscilando desde muy pobres a muy ricas. En oriente el taxón más común fue Asteraceae, seguido de Fabaceae, Solanaceae, Myrtaceae (principalmente Eucalyptus), Hypochaeris, Borreria y Hedyosmum y en el Suroeste fueron Coffea arabica y Cecropia agustifolia seguidos de Mimosa, Fabaceae, Cordia, Mangifera indica y Acalypha.