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  1. Se cree que el emblemático árbol de la Plaza de Pueblo Bonito fue un majestuoso pino que se encontraba en el patio oeste de la gran casa monumental durante el auge máximo del Fenómeno del Chaco (850-1140 dC). El tronco de pino ponderosa (Pinus ponderosa) fue descubierto en 1924, y desde entonces ha sido incluido en las narraciones de “nacimiento” y “vida” de Pueblo Bonito, aunque estas ideas no han sido rigurosamente probadas. Evaluamos tres posibles orígenes de crecimiento del árbol (JPB-99): Pueblo Bonito, Chaco Canyon, o una cordillera distante. Basado en líneas de evidencia convergentes—registros documentales, isótopos de estroncio ( 87 Sr / 86 Sr), y pruebas de procedencia de anillos de árboles—presentamos un nuevo origen para el Árbol de Plaza. No creció en Pueblo Bonito o incluso en el cercano Cañón del Chaco. Más bien, JPB-99 creció en las montañas Chuska, a más de 50 km al oeste del Cañón del Chaco. El árbol probablemente fue llevado a Pueblo Bonito en algún momento entre 1100 y 1130 dC, aunque por qué se dejó en el patio oeste, su significado, y cómo podría haber sido utilizado siguen siendo misterios. El origen del Árbol de la Plaza de Pueblo Bonito subraya los profundos lazos culturales y materiales entre las grandes casas del Cañón del Chaco y el paisaje de Chuska. 
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  2. Abstract Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical changes to ecosystems, fire danger is increasing, and fires are having increasingly devastating impacts on human health, infrastructure, and ecosystem services. Increasing fire danger is a vexing problem that requires deep transdisciplinary, trans-sector, and inclusive partnerships to address. Here, we outline barriers and opportunities in the next generation of fire science and provide guidance for investment in future research. We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the “firehose” of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways towards mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future. 
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  3. Abstract

    A central challenge in global change research is the projection of the future behavior of a system based upon past observations. Tree‐ring data have been used increasingly over the last decade to project tree growth and forest ecosystem vulnerability under future climate conditions. But how can the response of tree growth to past climate variation predict the future, when the future does not look like the past? Space‐for‐time substitution (SFTS) is one way to overcome the problem of extrapolation: the response at a given location in a warmer future is assumed to follow the response at a warmer location today. Here we evaluated an SFTS approach to projecting future growth of Douglas‐fir (Pseudotsuga menziesii), a species that occupies an exceptionally large environmental space in North America. We fit a hierarchical mixed‐effects model to capture ring‐width variability in response to spatial and temporal variation in climate. We found opposing gradients for productivity and climate sensitivity with highest growth rates and weakest response to interannual climate variation in the mesic coastal part of Douglas‐fir's range; narrower rings and stronger climate sensitivity occurred across the semi‐arid interior. Ring‐width response to spatial versus temporal temperature variation was opposite in sign, suggesting that spatial variation in productivity, caused by local adaptation and other slow processes, cannot be used to anticipate changes in productivity caused by rapid climate change. We thus substituted only climate sensitivities when projecting future tree growth. Growth declines were projected across much of Douglas‐fir's distribution, with largest relative decreases in the semiarid U.S. Interior West and smallest in the mesic Pacific Northwest. We further highlight the strengths of mixed‐effects modeling for reviving a conceptual cornerstone of dendroecology, Cook's 1987 aggregate growth model, and the great potential to use tree‐ring networks and results as a calibration target for next‐generation vegetation models.

     
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