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A general design method for buildings with energy dissipation devices
(National Information Centre of Earthquake Engineering, 2017) Llera Martin, Juan Carlos de la; Besa Vergara, Juan José
A general design procedure for elastic buildings equipped with linear and non-linear energy dissipating devices is presented herein. The procedure begins with an estimation of the total amount of equivalent damping and stiffness required to achieve a predefined building performance. The method defines the modal significance of some key design performance indicators, and then focuses on the control of the modal properties by solving a singular two-parameter eigenvalue problem. Although simple, the definition of a new measure of modal significance in the classical and non-classical damping case, is also critical for faster convergence of the method. The incorporation of non-classical damping in the design algorithm appears to be critical, and expands its applicability significantly. The design output provides a target frequency shift and damping ratio for the complete structure, obtained from the so called iso-performance design curves (IPCs), which cover the whole design space spanned by these two design variables representing the supplemental stiffness and damping of the devices. Once the linear equivalent properties of the dampers are obtained, the equivalent stiffness and damping of the devices are transformed into parameters that characterize the inelastic force-deformation constitutive models of the physical dampers. The design procedure does not require any a-priori definition of a specific damper type. The design procedure was validated using 8 conventional buildings that were severely damaged during the February 27, 2010 Chile earthquake, and a rather complex free-plan building with two towers of a rhomboid-shape plan. Estimation errors between response reduction factors using linear versus inelastic modeling of the EDDs were usually less than 10% for the 9 buildings considered. The design procedure proposed is better described as a conceptual and practical framework for the design of buildings with passive EDDs. Its step-by-step nature can take advantage of future research in any of the current research topics described herein and could be easily adapted to new knowledge in the field.
A long-stroke semi-active MR damper for building control using tuned masses
(National Information Centre of Earthquake Engineering, 2017) Zemp, René; Llera Martin, Juan Carlos de la; Almazán Campillay, José Luis; Weber, F.
In this research the comprehensive development of a long-stroke MR-damper designed to control the earthquake performance of an existing 21-story reinforced concrete building in Santiago (Chile) by reacting on one of its tuned masses is presented. The ±1 m stroke MR-damper design is quite unique and considered the nominal response of the building equipped with two pendular masses of weight 160 tons each, and tuned to the fundamental mode of the structure. The realscale long-stroke MR-damper was designed by our research team and manufactured in Chile. The MR-damper was tested using a special testing rig designed to study devices with long stroke at large deformation velocities. The rig was implemented in the dynamics and vibration control laboratory at Universidad Catolica de Chile. Both, the long-stroke MRdamper and the control algorithm were experimentally validated using a suite of periodic and seismic signals. For the building numerical simulations, the nominal MR-damper force-displacement constitutive relationship was replaced by the measured force-displacement response of the damper in order to validate the theoretical MR-damper model used. Such model was used in simulations to predict the performance of the TM-MR damper assembly in the design phase of the damper. Furthermore, a new real-time structural displacement sensor was developed with this application since conventional technology and methods to measure building displacement are inaccurate for a real-time displacement control as proposed with this application. The real-time building displacement sensor was validated using a scaled-down building prototype subjected to shaking table tests before an actual size sensor was implemented within a test building. All electronic components of the tuned-mass MR-damper assembly were tested with a shaking table and subjected to strong motion accelerations while the MR-damper was working in its active mode. It is concluded that the proposed tuned-mass MRdamper solution is technically feasible and may be advantageous in some real-life situations. The stage of development of the technology reached a point that enables commercial implementation in a real structure.
“A mi papá le gustaban y a mí también”: la memoria biocultural como fundamento de la práctica agroecológica
(2019) Monterrubio-Solís, Constanza; Barreau-Daly, Antonia; Urra, Romina; Ibarra Eliessetch, José Tomás
El movimiento por la masificación de la agroecología está logrando abrir espacios sociales y políticos para transformar el sistema alimentario a nivel global de una manera sin precedente. La adopción del término por parte de empresas, gobiernos, círculos académicos y organismos de la sociedad civil lleva implícita una amplia gama de interpretaciones del concepto y prácticas agroecológicas. Para las y los campesinos que han practicado la agricultura familiar por generaciones, el término agroecología puede parecer una moda más entre quienes diseñan programas desde alguna distante oficina. La memoria biocultural encuentra una de sus más diversas manifestaciones en la agricultura y la alimentación. La memoria biocultural, transmitida de generación en generación, representa un acervo inmaterial y ecológico que ha permitido a la humanidad manejar un ensamble de más de 5000 especies de plantas y animales, conociendo sus respectivos cuidados dentro de sistemas más amplios, así como las preparaciones para convertirlos en una amplia gama alimentos. La memoria biocultural se manifiesta en múltiples e interrelacionadas formas de conocimientos y prácticas asociadas al clima, los suelos, los ciclos biológicos, y han sido la base de la domesticación de la agrobiodiversidad. A raíz de la homogenización del sistema agrícola global, la memoria biocultural ha sido severamente diezmada, de tal manera que la agrobiodiversidad y las prácticas asociadas a la misma se encuentran hoy en día contenidas en personas cuya labor es recordar y aplicar lo que sus predecesores les enseñaron, adaptándose a los procesos de cambio actuales. En este trabajo, encuestamos a 83 agricultores de la región de La Araucanía, Chile, con respecto a las semillas que cultivan, sus prácticas de agricultura y alimentarias. A pesar de que la mayoría de las personas encuestadas no utilizan el término “Agroecología”, sus narrativas, prácticas y la diversidad de especies que cultivan dan cuenta de que la agricultura familiar es en gran medida compatible con los principios de la agroecología. Desde la perspectiva sistémica, el cuidado del suelo, de los ciclos y de las redes de reciprocidad que se tejen en los territorios, la memoria bio-cultural es la base del acervo sobre la cual la agroecología de vincularse con el día a día de la agricultura familiar. De esta manera, si bien la Agroecología plantea una diversidad de propuestas tanto técnicas como culturales para la transformación del sistema agrícola global, el marco de la memoria bio-cultural puede enriquecer su propuesta proporcionándole raíces y significado a nivel territorial.
A new method for assessing compatibility of consolodation procedures with conservation principles: Intervention Qualitiy Index
Llera Martin, Juan Carlos de la; Palazzi, Nuria Chiara; Misseri, Giulia; Sandoval, Cristián; Tonietti, Ugo; Rovero, Luisa
In current times, built heritage is being lost at an alarming rate due to natural and human hazards. Policies for its protection and rehabilitation involve, among other things, challenges related to the refinement of suitable structural strengthening approaches. The arduous balance between gaining acceptable safety levels for occupants without deploying intrusive devices, inconsistent with conservation principles such as those of the ICOMOS charters, is not a simple task. The interest and efforts of the scientific community in this regard have been increasing for decades, but still, it is the structural professional´s responsibility and experience which must define this arduous balance on a case-to-case basis. This study addresses the question: How can the quality of structural rehabilitation interventions be assessed in light of conservation principles such as those given by ICOMOS? Here, a preliminary method - called “Intervention Quality Index” (IQI) method is proposed. It assesses the restoration intervention quality in relation to: (i) the level of compliance given by the conservation´s principle score (conservation´s factor, CF); and (ii) the current state of conservation of the monument (safety factor of building considering the seismic intensity, Δs). The IQI method considers the compliance level of the designed reinforcement with conservation principle, formalized through the fulfillment of a category, i.e. respected, partially respected, and not respected. Then, these judgments are translated into scores and statistically evaluated. Scores are attributed in relation to the relevance of the fulfillment of a certain conservation principle (authenticity, minimal intervention and intrusiveness, compatibility, recognizability and reversibility) for the seismic structural safety point of view. Preliminary results show that an effective employment of traditional earthquake-resistant practices together with a wise use of modern retrofit strategies allow for the preservation and reinforcement of built heritage without harming its identity
Abundancias relativas y uso de hábitat por el chuncho (Glaucidium nanum) y el concón (Strix rufipes) en bosques primarios y antropizados de La Araucanía
(2008) Ibarra Eliessetch, José Tomás; Gálvez, Nicolás; Rojas, Isabel; Bonacic Salas, Cristian
El concón y el chuncho son dos búhos endémicos de Chile y Argentina. Las poblaciones de concón se encontrarían en declinación debido a la pérdida de bosques primarios. Contrariamente, el chuncho parece ser una especie tolerante a modificaciones de hábitat. Aquí, documentamos los registros de un estudio que tiene como objetivo determinar diferencias en abundancias relativas, uso de hábitat y morfometría (sólo de G.nanum en este caso), en bosques primarios y antropizados de la Región de la Araucanía. Seleccionamos ocho rodales (dos bajo presión de corta y pastoreo, dos de bosque secundario, dos primarios de mañío-tepa y dos primarios de araucaria). En cada uno cuantificamos variables estructurales e índices de perturbación, realizamos play-back nocturnos y recorridos diurnos, complementado con redes de captura. Del total de registros (chuncho, N=8; concón, N=15), la abundancia de ambas especies fue mayor en bosques primarios, tanto de araucaria (43,5%), como de mañío-tepa (34,8%), los que presentan mayor densidad de Chusquea spp. en el sotobosque (>1,28NC), DAP de árboles (>50,7cm), profundidad de hojarasca (>6,9cm), número de troncos caídos (>9 log/ha), y menores índices de perturbación (0,1-0,7). A pesar de que ambas especies están presentes en todos los tipos de hábitats estudiados, los bosques antiguos de mayor complejidad estructural, que se encuentran fundamentalmente en Áreas Silvestres Protegidas y sobre los 800 m.s.n.m, son los que sustentarían una mayor abundancia de estas rapaces nocturnas
Accidental and natural torsion in earthquake response and design of buildings
(1996) Chopra, A. K.; Llera Martín, Juan Carlos de la
Agricultura familiar campesina y cambio climático: observaciones y adaptaciones desde el sur de los Andes
(2021) Caviedes, Julián; Ibarra Eliessetch, José Tomás; Calvet-Mir, Laura; Braga Junqueira, André
El cambio climático, fenómeno de carácter global, afecta todos los rincones y comunidades humanas y no-humanas a escala local. Uno de los medios de vida más afectados, de manera negativa por el cambio climático, es la agricultura familiar campesina (AFC). La AFC es principalmente practicada por comunidades locales (i.e., campesinos indígenas y noindígenas) alrededor del mundo. Estas comunidades, a su vez, son las más vulnerables a los efectos negativos de estos cambios ya que su actividad principal depende directamente de los sistemas agrícolas. Paradójicamente, los conocimientos y necesidades de las comunidades locales sobre el cambio climático son raramente consideradas en la política pública. Los campesinos y campesinas tienen sus propias formas de percibir e interpretar los cambios en sus entornos y, según eso, implementan medidas para adaptarse a éstos. Durante enero y febrero de 2021, se realizaron entrevistas semiestructuradas a 15 campesinos mapuche y no mapuche en tres localidades de la comuna de Pucón, sur de los Andes, Chile, para documentar la percepción de comunidades locales con respecto a cambios ocurridos en el ambiente y clasificar el origen de éstos. Además, se documentaron las medidas de adaptación que están implementado para afrontar estos cambios. Los participantes hicieron, en total, 222 menciones sobre cambios ambientales, de las cuales 117 se clasificaron en 39 observaciones distintas de impactos del cambio climático en sus territorios. Entre los cambios más reportados producidos por el cambio climático destacaron cambios en la temperatura media y cambios en las lluvias. Resultados similares han sido reportados por otras comunidades agrícolas en el mundo. Por ejemplo, en Uganda los agricultores percibieron una disminución en las precipitaciones y un aumento en las temperaturas que, a su vez, estaban reduciendo los rendimientos de sus cultivos. Con respecto a las medidas de adaptación, las más mencionadas tuvieron relación con cambios en la crianza de ganado, uso de fertilizantes naturales y cultivosextensivos de granos y cereales. Estas medidas de adaptación, realizadas para mantener la resiliencia de la AFC, comparten un patrón similar alrededor del mundo. Por ejemplo, un estudio concluyó que la disminución en el número de cabezas de ganado era la principal medida de adaptación al cambio climático adoptada por ganaderos a nivel global. Estos resultados enfatizan que el conocimiento y las percepciones de comunidades locales con respecto al cambio climático debiesen ser integradas en políticas públicas para contrarrestar los efectos negativos que el cambio climático está teniendo sobre la AFC.
American mink in the Cape Horn Biosphere Reserve, southern Chile: a population and community approach to understand a recent island invasion
(2009) Ibarra Eliessetch, José Tomás; Schüttler, Elke; Altamirano Oyarzún, Tomás Alberto; Rozzi, Ricardo; Bonacic Salas, Cristian
Since 2001 exotic Mustela vison has been known to populate Navarino, an island located in the pristine Cape Horn Archipelago (54-55ºS). As an invasive predator, it could be affecting the biodiversity that evolved in absence of mammalian terrestrial predators. We report the abundance (using live-trapping and sign surveys) of mink and its seasonal impact (through bird sampling, diet analysis, and artificial nest predation) upon the wetland bird community. Mink signs were found in 79% of the surveys in all types of semi-aquatic habitats. Yet, relative population abundance (0.75 mink/km of coastline) was still below densities measured in other invaded or native areas. The habitat model accuracies indicated that mink were less specific in habitat use, probably due to the missing limitations normally imposed by predators or competitors. The selected models predicted that mink prefer to use shrubland instead of open habitat, coastal areas with heterogeneous shores instead of flat beaches, and interestingly, that mink avoid habitats strongly modified by beavers. Fifty-six bird species were registered with marked seasonal variations in richness and total number of birds. Near half (48%) of bird species were migratory, arriving to the area in summer. Seasonal differences in the diet of M. vison were observed (n=414 scats). Scat analysis showed fragments of birds in 36% of the samples collected during summer, but only 21% in winter scats. This agrees with the increase in the number of birds during their reproductive period. Species like Chloephaga picta and some passerine birds are at a greater risk of being predated by mink. Conversely, predation of mink on artificial nests was very low. Our results shows that mink have colonised the entire island and is opportunistically predating on birds. For the management of mink, we suggest the establishment of rocky coastal shores as priority sites deserving special conservation efforts.
An international student program in social-ecological systems: sustainable forest management and resilience thinking from local Andean-Patagonian forests to the world
(2018) Ibarra Eliessetch, José Tomás; Gálvez, Nicolás; Bascopé, Martín; Luna, Laura; Salazar, Gonzalo
The interconnected challenges of building resilience and generating sustainable forestry practices demand a holistic appreciation of social-ecological systems and requires us to step beyond disciplines to gain a broader understanding of the world. The Pontifical Catholic University of Chile (QS Standard ranked #1st in Latin America) offers an academic program consisting of 5 modules where students and lecturers bring together different perspectives in order to generate sound research questions and propose innovative solutions to real-world problems in environmental, forestry, and socio-cultural issues. The main objective of the program is to promote a holistic and critical understanding of forest and culture interactions based on an interdisciplinary methodology with a strong practical-based work. An integrative set of modules fosters greater links between the natural and social sciences, in order to engage with the complex issues of biodiversity conservation, forest management, inter-ethnic relations, and policy-making for sustainable development. The program comprises the following courses: 1. Latin American Conservation; 2. Conservation of Forest Ecosystems and Wildlife; 3. Territory, Interculturality and Education for Sustainability; 4. Interdisciplinary Methods for Inquiring Social-Ecological Systems; and 5. Planning for Sustainability. This program can be adapted for either undergraduate or graduate students, and for a full term or an intensive summer school. It takes place at the southern campus of the Pontifical Catholic University of Chile (Sede regional de villarrica Campus) and its surroundings, a unique setting in southern Chile characterized by multiple land covers/uses (forests, volcanoes, lakes, rivers, human settlements and protected areas) and cultural backgrounds (indigenous peoples, non-indigenous peasants, immigrants, and long-term settlers). In this presentation we introduce the aims, content and the potential of this program for forestry students from around the world
Análisis y diseño del Hospital Militar
(2002) Stagno, Patricio; Frerk, Jaime; Stagno, Daniel; Rendic, Percy; Iturriaga, Waldo; Llera Martín, Juan Carlos de la; Lüders, Carl; Sady, Henry; Guendelman, Tomás; Guendelman, Mario; Lindenberg, Jorge; Astudillo, Misael; Boroschek, Rubén
Este artículo describe brevemente algunos resultados del análisis y diseño del edificio placa-técnica del nuevo Hospital Militar ubicado en la comuna de la Reina en Santiago. Dicho edificiocuenta con una superficie cercana a los 50 mil metros cuadrados. Por brevedad, se enfatizaúnicamente aquellos aspectos más novedosos de su diseño, entre ellos, el del sistema de aislaciónsísmica basado en el uso de aisladores elastoméricos. A la fecha, este edificio es el más grande quehaya sido proyectado con aislación sísmica en América Latina. Se discuten además aspectosgenerales de la modelación estructural del edificio y los resultados más importantes del análisisdinámico realizado. En particular, se comparan las respuestas para un modelo tridimensional deledificio con el supuesto de comportamiento lineal equivalente y no-lineal del sistema de aislación
Analytical and experimental response of asymmetric structures with frictional and viscoelastic dampers
(2004) Llera Martin, Juan Carlos de la; Almazán Campillay, José Luis; Vial, Ignacio; Ceballos, Victor; García, Marcos
This article summarizes analytical and experimental results of linear asymmetric structures with frictional and viscoelastic dampers. Such energy dissipation devices may prove useful in controlling the uneven deformation demand occurring in structural members of torsionally unbalanced structures. Torsional balance is defined as a property of an asymmetric structure that leads to similar deformation demand in structural members equidistant from the geometric center of the building plan. It can be defined in a strong or a weak form. The latter, which allows for rotation of the building plan, only implies an equal norm of the displacement demand at resisting planes symmetric with respect to the geometric center. In general, it can be achieved by the use of energy dissipation devices by making the so-called empirical center of balance of the structure to lie on top of the geometric center. Shaking table results conducted on a mass and stiffness asymmetric six-story model with frictional dampers support the analytical results and the concept of weak torsional balance. Similar results may be extended to the use of viscoelastic dampers as well as for inelastic multistory asymmetric structures.
Analytical methods to assess the collapse and damage of reinforced concrete walls
(National Information Centre of Earthquake Engineering, 2017) Jünemann Ureta, Rosita; Llera Martin, Juan Carlos de la; Hube Ginestar, Matías Andrés
During the great 2010, Chile earthquake, reinforced concrete (RC) buildings showed adequate performance. However, in some of them a particular damage pattern involving brittle failure of RC walls was observed in the lower stories, usually associated with high axial loads and vertical irregularities. The brittle nature of the failure led to a sudden degradation of the bending capacity and lateral stiffness of the walls. Significant research including experimental campaigns and numerical models has been conducted in order to describe the observed damage in RC walls and identify the possible causes of this behavior. This research studies the collapse and damage of shear wall buildings during the Maule earthquake using state-of-the-art analytical models. The proposed analytical research lies within the family of micro models, and uses finite element models with 4-node shell elements to represent the physical interactions that occur in the wall section at finite element level. Inelastic finite element models were developed in DIANA, and the concrete was modeled following the total strain rotating crack approach. First, different stress-strain constitutive relationships for concrete in compression were evaluated and validated with experimental data. The stress-strain constitutive laws were regularized by preserving the compressive fracture energy, for both, unconfined and confined concrete. Once the constitutive models were validated, a real RC resisting plane damaged during the 2010, Chile earthquake was studied in detail, and the observed damage pattern reproduced by means of two-dimensional inelastic pushover analysis. It can be shown that the damage geometry of the shear wall cannot be correctly represented by conventional inelastic models that ignore the true deformation kinematics with lateral and axial interaction. Indeed, the failure mechanism of resisting planes shows strong coupling between lateral and vertical deformations in the plane. Finally, results of a threedimensional inelastic dynamic analysis of the entire building are presented, which show to be consistent with the observed damage after the earthquake and with the 2D model results.
Aphrastura spinicauda change their reproductive strategy with altitude in the Andean temperate forest of South America
(2015) Altamirano, Tomás A.; Ibarra Eliessetch, José Tomás; Maza, Mariano de la; Navarrete, Sergio A.; Bonacic Salas, Cristian
Elevational gradients have been proposed as a driver of change in avian reproductive lifehistory strategies. The eventual shorter breeding season and higher predation risk at highaltitudes can produce a decline in fecundity, a reduction of clutch sizes, and an increase inparental care and survival. We studied whether the breeding strategy of the Aphrasturaspinicauda varies along an elevation gradient in the Andean temperate forests of Chile. Weinstalled 240 nest-boxes between 260 and 1,115 m a.s.l., and monitored the breedingactivity of 162 nests over two seasons (2010-2011, 2011-2012). As predicted, the breedingseason was 28% and 55% shorter in highland forests during the two seasons. Timing of egglaying (1 egg every second day) and incubation period (average 15 days) did not vary withaltitude. We found smaller clutch sizes (average 4.1 vs. 4.5), a fewer number of nestlingsper clutch (average 3.5 vs. 4.2), and longer nestling period (22.2 vs. 21.6 days) in highlandthan lowland forests. The breeding success declined with altitude, mainly due to predationby the Dromiciops gliroides which was 83% in highland and 35% in lowland forests. Ourfindings suggest that Aphrastura spinicauda change their reproductive strategy alongaltitudinal gradients to a slower one, likely as an adaptation to shorter breeding seasons.Yet, these changes do not appear to compensate for the increased predation rates at higherelevations, questioning the potential adaptive significance of this strategy
Are ecosystem engineers keystone habitat providers for secondary cavity nesters in temperate forests of South America?
(2021) Cuatianquiz-Lima, Cecilia; Altamirano, Tomás A.; Novoa, Fernando; Ibarra Eliessetch, José Tomás
Ecosystem engineers influence resource availability for other organisms, and thus they play important roles as drivers of community assembly. We investigated the relationship between nest occurrence of secondary cavity nesters (SCNs: Thorn-tailed rayadito, Chilean swallow, and Southern house wren) and their selection of cavities supplied by five ecosystem engineers (Magellanic woodpecker, Chilean flicker, Striped woodpecker, White-throated treerunner and rot fungi/insects) in a Global Biodiversity Hotspot, southern Chile. Further, we quantified the reproductive success of SCNs as a function of the characteristics of cavities (internal volume, entrance size and height) supplied by ecosystem engineers. We searched for nests during 10 breeding seasons and monitored each nest to determine cavity origin, nest fate and quantified cavity characteristics. We found 842 nests for our three SCNs. Most nests (>80%) of rayaditos and house wrens were placed in cavities supplied by Rot fungi/insects with relatively small volumes (1976 ± 121.7 and 1857 ± 185.6 cm3 , respectively) but with different entrance sizes and heights. Swallow nests were placed in high cavities (8.2 ± 0.42 m)with small-sized entrances (3.4 ± 0.11 cm), and chiefly supplied by White-throated treerunners (56%). Reproductive success of SCNs varied between 50-65%, but the cavity characteristics showed no influence on the reproductive success of any species. Rot fungi/insects play a major role as ecosystem engineers for SCNs, however some ecosystem engineers may be functionally similar. The conservation of populations of SCNs may require the development of different management actions for each key ecosystem engineer in temperate forest of South America.
Avian diversity above the clouds: comparing elevational patterns in north and south temperate mountains
(2018) Altamirano Oyarzún, Tomás Alberto; De Zwaan, Devin; Ibarra Eliessetch, José Tomás; Martin, Kathy
Mountain ecosystems comprise 24% of the land-base of the Americas, and are critical components of the life-cycle for 35% of North American bird species. Globally, however, high elevation avian communities are poorly monitored, with taxonomic and functional diversity receiving little attention. In 2017, we initiated a temperate montane bird study, comparing: i) taxonomic and functional turnover across three habitats increasing in elevation: upper montane (>50% tree cover), subalpine (5-50% tree cover), and alpine (<5% tree cover), and ii) the breeding strategies of alpine birds in North and South America. We conducted 600 diurnal bird point counts in six North temperate (British Columbia, Canada; 54°N latitude) and 10 South temperate mountains (Chile; 39°S latitude). Species richness was comparable between sites (49-54 species), but decreased with elevation in Canada (upper montane: 31, alpine: 16) compared to remaining consistent across elevation in the Chilean Andes (~33 in each habitat). Species composition among mountains was highly variable in both hemispheres (Jaccard index < 0.5) indicating potential variation in drivers such as habitat structure. We found contrasting patterns in alpine breeding strategies, as open-cup nesters made up 88% (14/16 species) of the Canadian alpine community, while 100% of the 37 nests (6 species) found in the Chilean alpine were cavity nesters (rock crevices or ground excavations). Comparing high elevation temperate ecosystems in the Americas provides a strong framework to address avian breeding dynamics in stochastic environments, as well as understand the potential conservation value of mountain habitats as refugia for avian populations with environmental change
Bajan la montaña, llaman la lluvia: las aves en la meteorología tradicional mapuche en el bosque templado andino
(2014) Ibarra Eliessetch, José Tomás; Barreau, Antonia
El conocimiento tradicional se asemeja al conocimiento científico occidental en que los dos se basan en la acumulación de observaciones y evaluaciones empíricas. Las culturas de montaña han logrado un conocimiento de la meteorología local en base a la reiterada observación del comportamiento de la fauna circundante. Este “conocimiento meteorológico tradicional” favorece el manejo adaptativo de los recursos naturales y la resiliencia de los sistemas socio-ecológicos frente a eventos de incertidumbre climática. Exploramos el rol de las aves como indicadoras de cambios en la meteorología mapuche de la zona andina del sur de Chile. Además, analizamos las prácticas de manejo de recursos que fueron gatilladas por las aves identificadas para este fin. Entre 2012-2013, hicimos etnografía, entrevistas informales, entrevistas semi-estructuradas y ejercicios de identificación de especies en dos comunidades de La Araucanía. Doce especies de aves (Üshüm) fueron identificadas por los informantes como indicadoras de cambios meteorológicos. De acuerdo a ellos, siete especies descienden de la cordillera cuando se avecinan malas condiciones (nieve, lluvia y/o tormenta). Las aves indicadoras permitieron a los agricultores reducir la incertidumbre asociada al manejo de recursos naturales, tales como la protección del ganado de tormentas, cosecha y enfardado de forraje, cosecha de manzanas para la fabricación de chicha, colecta de piñones y leña, junto con otras actividades sensibles a las condiciones del clima. Adicionalmente, encontramos una similitud entre las observaciones locales sobre el descenso de las aves desde la cordillera y el conocimiento científico sobre cambios estacionales en las abundancias de aves a través del gradiente altitudinal. La meteorología tradicional podría enriquecer programas educativos sobre aves, cultura local y manejo de recursos naturales. Estos métodos tradicionales se debieran integrar con técnicas modernas en políticas orientadas a suplir las demandas de predicción meteorológica en localidades y momentos específicos en un contexto de cambio climático.
Biocultural memory and transitions in mountain food systems: the case of two indigenous communities from Chile and Mexico
(2018) Monterrubio-Solís, Constanza; Barreau, Antonia; Ibarra Eliessetch, José Tomás
Food is not only nourishment. Food feeds knowledge, practices, and beliefs through generations, and thus it sustains biocultural memories. However, prevailing economic models homogenize biocultural food systems by replacing local diversity with fewer market products, often leading to nutrition-related chronic diseases. This research explores local biocultural memories around cooking spaces, wild food gathering and home gardens to reveal changes in foodways in families from Andean landscapes in Mapuche territory, Chile, and from Chiapas’ Highlands in Tzotzil territory, Mexico. We used food diary elicitation, participant observation, and informal and semi-structured interviews. In both cases, food items have changed, as has the way they are procured and prepared. Traditional foods are being replaced by foods associated with modernity and progress. Perceived drivers of change include shifts iŶ childreŶ’s food prefereŶces, lack of tiŵe for food procurement and temporary migration, and a decreasing production of grains and vegetables caused by reduced land tenure and soil depletion. Data show that the intake of locally procured ingredients is higher than intake of market-based products during the summer season, while consumption of market-based foods increases during seasonal scarcity. Rice and noodles have replaced traditional foods like locro, soplillo, and quinwa among Mapuche families, while noodles, industrial tortillas, and soda are replacing corn tortillas, quelites and pozol among Tzotzil families. Though distant, mountain food systems from Mexico and Chile face similar processes of biocultural homogenization with notorious increases in nutritionrelated chronic diseases such as type 2 diabetes, obesity, and hypertension. Biocultural memory is a powerful link to recall food-related experiences and practices. This can be the basis for culturally appropriate and healthy eating habits, and to recover local diversity thus strengthening food systems and sovereignty.
Birds in the web of life: ecology and conservation of nest webs worldwide
(2018) Cockle, Kristina L.; Ibarra Eliessetch, José Tomás
Avian communities are comprised of species that interact locally, producing complex networks whose dynamics cannot always be understood or predicted from information at the population level. Globally, more than 1500 species of birds interact around the resource of tree cavities, which they require for nesting or roosting. These cavity-nesting communities are structured in nest webs – interspecific interaction networks that link secondary cavity-nesting species (non-excavators including birds, mammals, and social insects) to the species that provide (trees) or facilitate cavities (woodpeckers and other avian excavators and organisms that promote wood decay). Because the supply of cavities can be limited, and can change dramatically over time and space, nest web structure may determine how cavity-nesting communities respond to perturbation. This symposium will showcase recent progress in the study of cavity-nesting communities as interaction networks, explore how nest webs change across space and time, and propose research and management to improve conservation outcomes for these communities.
Breeding strategies of passerines in the world’s southernmost forests
(2018) Ibarra Eliessetch, Jose Tomas; Jara, R. F.; Crego, R.; Arellano, F.; Altamirano A., Tomás; Rozzi, R.; Joménez, J.E.
Species with wide breeding ranges have evolved different breeding strategies at different latitudes. Most passerines breeding in the South American temperate forest biome (30-55 S) have wide breeding ranges; however, most studies have been conducted in its northern region (30-42°S). Here for the first time, and during three breeding seasons (2014-2017), we monitored 102 nests of the five most abundant open-cup forest-dwelling passerines in the Cape Horn Biosphere Reserve, Navarino Island (55°S), southern Chile. Additionally, we compared the breeding strategies of the Austral Thrush (Turdus falcklandii) to other breeding populations at lower latitudes (33°S and 39°S). Most species started laying eggs the last week of September. The White-crested Elaenia (Elaenia albiceps) started breeding two months later. The Tufted-tit Tyrant (Anairetes parulus) was the most specialized in terms of nest substrate and Turdus the least. We found that Turdus had larger clutch sizes and nested closer to the ground on Navarino Island than the northern populations. The difference in clutch size corresponds with the described pattern of larger clutch sizes at higher latitude, and for species nesting on islands. The difference in nest height from the ground could be attributed to evolution in the absence of ground predators on Navarino. This behavior, however, could put them at a higher risk of predation by a recently introduced mammalian predator, the American mink (Neovison vison). By better understanding the breeding biology of these species, further research can be conducted to understand differences in breeding strategies among populations and factors affecting breeding success
Caracterización florística de las dunas del humedal Salinas de Pullally en Chile central
(2010) Rojas, Isabel; Torres, Pamela; Altamirano Oyarzún, Tomás Alberto; Gálvez, Consuelo; Petitpas David, Robert; Ohrens, Omar; Ibarra Eliessetch, José Tomás
Se realizó una caracterización florística y fisionómicas de las dunas asociadas al humedal Salinas de Pullally, en 6 microhábitat distintos. Las especies más abundantes en el área son Ambrosia Chamissonis y Carpobrotus chilensis, lo que indica el estado activo de las dunas presentes en el área.

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