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Influencia del clima sobre crecimiento de Roble (Nothofagus obliqua (Mirb.) Oerst.) y resiliencia de la especie frente a las sequías en el centro-sur de ChileLibroDebido a la importancia de la especie roble y a que no existen estudios que hayan evaluado cómo el cambio climático puede afectar su crecimiento, los objetivos de este trabajo son los siguientes: Evaluar la relación entre el crecimiento radial (en ancho de anillos) y el clima en renovales de roble a lo largo de su distribución en la Cordillera de Los Andes. Evaluar la resiliencia del crecimiento de roble a las sequías ocurridas en décadas recientes y si las poblaciones creciendo en el norte de su distribución han sido afectadas por la megasequía. Evaluar si existe alguna tendencia en la productividad primaria de estos renovales durante las últimas dos décadas, a través del Índice de Vegetación de Diferencia Normalizada (NDVI) para todo el gradiente latitudinal en la Cordillera de los Andes. Climate response and drought resilience of Nothofagus obliqua secondary forests across a latitudinal gradient in south-central ChileArtículo de revistaThe climate response and resilience of tree growth to drought events have been widely reported for forests from the Northern Hemisphere. However, studies are much scarcer in the extra-tropical forests of southern South America. Mediterranean and Temperate forests of Chile are suffering from a moderate warming and a sustained precipitation decrease, occurring on top of an unprecedented megadrought since 2010. This study evaluated tree-growth patterns, the climate response and drought resilience of nine secondary Nothofagus obliqua forests across a latitudinal gradient from Mediterranean to Temperate climate in the Andes of Chile (35.7° to 40.3° S). Moreover, to improve the understanding of the spatial variation in productivity patterns, this research assessed trends in the maximum Normalized Difference Vegetation Index (peak in the NDVI) across the gradient for 2001–2018. Tree-growth patterns were highly influenced by stand dynamics, with steep decreasing trends in most of the stands related to a gradual canopy closure. Productivity trends had a flat pattern north of 38oS, but positive trends south of this latitude, which were mostly attributed to stand development. Tree growth was positively related to precipitation in all the sites, with annual and summer rainfall being more important in the north (Mediterranean climate) and south (Temperate climate), respectively. Conversely, maximum temperature had a negative effect on growth in most of the studied forests. This implies that projected warmer and drier conditions may have a detrimental effect on N. obliqua growth during coming decades. The two northern stands, located at the species dry range edge, were among the most resilient to drought and have not been strongly affected by the current megadrought in the area. Overall climate conditions, however, do not define the tolerance of stands to droughts, likely because local environmental and forests conditions play a key role. Although droughts have not strongly impacted the growth of N. obliqua across its distribution so far, future studies should assess the effects of the current long-term megadrought on growth resilience, and physiological studies should address the impacts of droughts and heat waves on forest function beyond what growth can unveil. +A 5680-year tree-ring temperature record for southern South AmericaArtículo de revistaIt is widely documented that the Earth’s surface temperatures have increased in recent decades. However, temperature increment patterns are not uniform around the globe, showing different or even contrasting trends. Here we present a mean maximum summer temperature record, based on tree-ring widths, over the past 5682 years (3672BC – 2009AD) for southern South America (SSA), covering from mid-Holocene to the present. This is the longest such record for the Southern Hemisphere (SH), and expands available annual proxy climate records for this region in more than 2060 years. Our record explains 49% of the temperature variation, and documents two major warm periods between 3140–2800BC and 70BC – 150AD, which coincide with the lack of evidence of glacier advances in SSA. Recent decades in the reconstruction (1959–2009) show a warming trend that is not exceptional in the context of the last five millennia. The long-term relationship between our temperature reconstruction and a reconstructed total solar irradiance record, with coinciding cycles at 293, 372, 432–434, 512 and 746 years, indicate a persistent influence of solar forcing on centennial climate variability in SSA. At interannual to interdecadal scales, reconstructed temperature is mainly related to the internal climate variability of the Pacific Ocean, including El Niño Southern Oscillation (ENSO) and longer oscillations. Our study reveals the need to characterize regional-scale climate variability and its drivers, which in the context of global-scale processes such as anthropogenic warming, interact to modulate local climate affecting humans and ecosystems. Estado de conservación de Fitzroya cupressoides en la región de Los Lagos, Chile. Desafíos para su conservación y restauraciónArtículo de revistaEn el presente estudio, en base a coberturas regionales de información geográfica del Catastro de Recursos Vegetacionales de Chile (CONAF), se caracteriza la situación actual de los alerzales de la región de Los Lagos, se describe la matriz que los circunda, y se discute sobre los principales desafíos para su conservación y restauración.