Browsing by Author "Galleguillos, Mauricio"

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    Assessing the socio-economic and land-cover drivers of wildfire activity and its spatiotemporal distribution in south-central Chile
    (2022) Pozo, Rocio A.; Galleguillos, Mauricio; Gonzalez, Mauro E.; Vasquez, Felipe; Arriagada, Rodrigo
    Sustained human pressures on the environment have significantly increased the frequency, extent, and severity of wildfires, globally. This is particularly the case in Mediterranean regions, in which human-caused wildfires represent up to 90% of all recorded wildfire ignitions. In Chile, it has been estimated that nearly 90% of wildfires are related to human activities, and that their frequency and distribution have steadily increased over the last decade. Despite this, the role of socio-economic factors in driving wildfire activity and its spatiotemporal distribution remains unclear. In this study, we assess the association between socio-economic drivers and spatiotemporal patterns of wildfires in the Mediterranean region of south-central Chile over the period 2010-2018. Our results show that 98.5% of wildfires are related to human activities, either accidentally (58.2%) or intentionally (36.6%). Wildfires occurred primarily during the summer months and their density at the commune-level was associated with increased road access, as well as with the percentage of land covered by agriculture, exotic tree plantations, and native forest. Wildfire activity at the commune-level was also related to socio-economic variables such as population density, proportion of indigenous population, and unemployment rate, although such associations varied considerably depending on the region and on whether the wildfire was started accidentally or intentionally. Our study provides a comprehensive and interdisciplinary assessment of the complex ways in which land-cover and socio-economic factors drive the distribution of wildfire activity in south-central Chile. It represents an important guide for policy-making, as well a baseline for research into strategies aimed at predicting and mitigating wildfire activity at both local and national levels.
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    Comparison of carbon and water fluxes and the drivers of ecosystem water use efficiency in a temperate rainforest and a peatland in southern South America
    (2024) Perez-Quezada, Jorge F.; Trejo, David; Lopatin, Javier; Aguilera, David; Osborne, Bruce; Galleguillos, Mauricio; Zattera, Luca; Celis-Diez, Juan L.; Armesto, Juan J.
    The variability and drivers of carbon and water fluxes and their relationship to ecosystem water use efficiency (WUE) in natural ecosystems of southern South America are still poorly understood. For 8 years (2015-2022), we measured carbon dioxide net ecosystem exchange (NEE) and evapotranspiration (ET) using eddy covariance towers in a temperate rainforest and a peatland in southern Chile. NEE was partitioned into gross primary productivity (GPP) and ecosystem respiration ( R eco ), while ET was partitioned into evaporation ( E ) and transpiration ( T ) and used to estimate different expressions of ecosystem WUE. We then used the correlation between detrended time series and structural equation modelling to identify the main environmental drivers of WUE, GPP, ET, E and T . The results showed that the forest was a consistent carbon sink ( - 486 +/- 23 g C m - 2 yr - 1 ), while the peatland was, on average, a small source (33 +/- 21 g C m - 2 yr - 1 ). WUE is low in both ecosystems and likely explained by the high annual precipitation in this region ( similar to 2100 mm). Only expressions of WUE that included atmospheric water demand showed seasonal variation. Variations in WUE were related more to changes in ET than to changes in GPP, while T remained relatively stable, accounting for around 47 % of ET for most of the study period. For both ecosystems, E increased with higher global radiation and higher surface conductance and when the water table was closer to the surface. Higher values for E were also found with increased wind speeds in the forest and higher air temperatures in the peatland. The absence of a close relationship between ET and GPP is likely related to the dominance of plant species that either do not have stomata (i.e. mosses in the peatland or epiphytes in the forest) or have poor stomatal control (i.e. anisohydric tree species in the forest). The observed increase in potential ET in the last 2 decades and the projected drought in this region suggests that WUE could increase in these ecosystems, particularly in the forest, where stomatal control may be more significant.
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    Estudio retrospectivo que compara dosis bajas versus dosis estándar de bortezomib en pacientes con mieloma múltiple
    (2015) Espinoza Zelada, Marcela; Befferman Cordóva, Nicole; Ocqueteau Tachini, Mauricio; Ramírez Villanueva, Pablo Antonio; Galleguillos, Mauricio; Sarmiento Maldonado, Mauricio
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    Evolution of air quality in Santiago : the role of mobility and lessons from the science-policy interface
    (2018) Gallardo, Laura; Barraza, Francisco; Ceballos, Andrés; Galleguillos, Mauricio; Huneeus, Nicolás; Lambert, Fabrice; Ibarra, Cecilia; Munizaga, Marcela A.; O'Ryan, Raúl E.; Osses, Mauricio; Tolvett, Sebastián; Urquiza, Anahí; Véliz, Karina D.
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    Haploidentical transplantation outcomes are comparable with those obtained with identical human leukocyte antigen allogeneic transplantation in Chilean patients with benign and malignant hemopathies
    (2020) Sarmiento, Mauricio; Ramirez, Pablo; Jara, Veronica; Bertin, Pablo; Galleguillos, Mauricio; Rodriguez, Isabel; Lorca, Carla; Pizarro, Isabel; Rivera, Elizabeth; Ocqueteau, Mauricio
    Introduction: Patients with benign or malignant blood disorders, who require allogeneic stem cell transplantation and lack an identical human leukocyte antigen HLA identicalHL sibling donor, could be transplanted with hematopoietic stem cells from unrelated adult or umbilical cord donors. However, in our country, both approaches are costly and time-consuming options.
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    Is the change deforestation? Using time-series analysis of satellite data to disentangle deforestation from other forest degradation causes
    (2024) Fuentes, Ignacio; Lopatin, Javier; Galleguillos, Mauricio; Ceballos-Comisso, Andrés; Eyheramendy, Susana; Carrasco Schmidt, Rodrigo Arnaldo