Año: 2017
Autor: Julián Caviedes, José Tomás Ibarra
Línea: Sustentabiliadad de Sistemas Socio-ecológicos
Tipo de publicación: Artículo
Publicado en: Plos One, DOI:10.1371/journal.pone.0169450
Título: Influence of Anthropogenic Disturbances on Stand Structural Complexity in Andean Temperate Forests: Implications for Managing Key Habitat for Biodiversity

Julián Caviedes, José Tomás Ibarra

 

Forest attributes and their abundances define the stand structural complexity available as habitat for faunal biodiversity; however, intensive anthropogenic disturbances have the potential to degrade and simplify forest stands. In this paper we develop an index of stand structural complexity and show how anthropogenic disturbances, namely fire, logging, livestock, and their combined presence, affect stand structural complexity in a southern Global Biodiversity Hotspot. From 2011 to 2013, we measured forest structural attributes as well as the presence of anthropogenic disturbances in 505 plots in the Andean zone of the La Araucanía Region, Chile. In each plot, understory density, coarse woody debris, number of snags, tree diameter at breast height, and litter depth were measured, along with signs of the presence of anthropogenic disturbances. Ninety-five percent of the plots showed signs of anthropogenic disturbance (N = 475), with the combined presence of fire, logging, and livestock being the most common disturbance (N = 222; 44% of plots). The lowest values for the index were measured in plots combining fire, logging, and livestock. Undisturbed plots and plots with the presence of relatively old fires (> 70 years) showed the highest values for the index of stand structural complexity. Our results suggest that secondary forests < 70- year post-fire event, with the presence of habitat legacies (e.g. snags and CWD), can reach a structural complexity as high as undisturbed plots. Temperate forests should be managed to retain structural attributes, including understory density (7.2 ± 2.5 # contacts), volume of CWD (22.4 ± 25.8 m3/ha), snag density (94.4 ± 71.0 stems/ha), stand basal area (61.2 ± 31.4 m2/ha), and litter depth (7.5 ± 2.7 cm). Achieving these values will increase forest structural complexity, likely benefiting a range of faunal species in South American temperate forests.

 

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Año: 2018
Autor: Romina Urra y José Tomás Ibarra
Línea: Sustentabiliadad de Sistemas Socio-ecológicos
Palabras Clave: Agricultura de subsistencia, conocimiento tradicional, conservación, pequeña agricultura, sistemas socio-ecológicos, soberanía alimentaria
Tipo de publicación: Artículo
Publicado en: Revista Etnobiología, Vol 16, Num. 1. pp 31-46
Título: ESTADO DEL CONOCIMIENTO SOBRE HUERTAS FAMILIARES EN CHILE: AGROBIODIVERSIDAD Y CULTURA EN UN MISMO ESPACIO

Romina Urra y José Tomás Ibarra

Las huertas familiares son sistemas socio-ecológicos que cumplen un importante papel en la conservación de la agrobiodiversidad y de procesos socio-culturales locales. Con base en distintas fuentes bibliográficas, se compiló y analizó la información existente sobre las huertas familiares en Chile, especialmente los datos referidos a composición, riqueza y usos de especies vegetales. Se analizó la información según zona geográfica norte (N), centro-sur
(CS) y sur (S) del país. Se encontraron 46 estudios, los cuales reportaron 125 especies cultivadas pertenecientes a 46 familias a nivel nacional. Del total, predominaron las plantas usadas en la alimentación (54%) y medicina (23%). Mediante el Índice de Jaccard se obtuvo una mayor similitud entre las familias de plantas cultivadas en las zonas CS y S (47%), seguido por N y S (31%). Quince familias de plantas fueron exclusivas para la zona N, nueve para la zona CS y tres para la S. De las 125 especies registradas, al menos 25 (20%) se cultivaban desde épocas pre-hispánicas (previo a 1541). Algunas especies como Chenopodium quinoa, Zea mays, Phaseolus coccineus, Solanum tuberosum y Capsicum annuum, fueron ampliamente reportadas a la llegada de los españoles, junto a otras ya extintas como Madia sativa y Bromus mango. Existe un bajo conocimiento sobre la diversidad de plantas cultivadas dentro de las huertas en Chile. En la huerta familiar se genera activamente una trama de conocimientos que permiten la mantención de especies vegetales y procesos culturales asociados. La actual disminución de la pequeña agricultura en Chile podría producir una erosión cultural y, en consecuencia, de la agrobiodiversidad asociada a las huertas familiares.

 

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Año: 2019
Autor: TOMÁS A. ALTAMIRANO,MARÍA TERESA HONORATO, JOSÉ TOMÁS IBARRA, MARIANO DE LA MAZA, DEVIN R. DE ZWAAN, CRISTIÁN BONACIC AND KATHY MARTIN.
Línea: Sustentabiliadad de Sistemas Socio-ecológicos
Palabras Clave: altitude, Austral Opossum, breeding, Chile, Thorn-Tailed Rayadito
Tipo de publicación: Artículo
Publicado en: Austral Ecology 44, 691-701
Título: Elevation has contrasting effects on avian and mammalian nest traits in the Andean temperate mountains

TOMÁS A. ALTAMIRANO,MARÍA TERESA HONORATO, JOSÉ TOMÁS IBARRA, MARIANO DE LA MAZA, DEVIN R. DE ZWAAN, CRISTIÁN BONACIC AND KATHY MARTIN.

 

Nest building is a widespread breeding strategy across taxa. Nest composition and structure can playa critical role in the breeding success and/or adult survival of nest-building vertebrates. Although nest traits are expected to vary adaptively across elevational gradients, few studies address this relationship. We studied the variation in nest traits (composition and structure) across elevation for two taxa with two different functions in the Andean temperate forests of southern Chile: a bird (Aphrastura spinicauda, Furnariidae, 170 breeding nests) and a marsupial mammal (Dromiciops gliroides, Microbiotheriidae, 91 winter torpor nests). For A. spinicauda, we further assessed how nest traits influenced clutch size and hatching success. Both species used fewer types of nest materials (items) with increasing elevation, and a greater proportion of leaves were used in highland compared to lowland forests. Aphrastura spinicauda used feathers and hair, and D. gliroides used bryophytes more frequently in lowland forests. The mass and volume of nests decreased with increasing elevation for A. spinicauda and increased for D. gliroides. Nest traits had subsequent fitness consequences for A. spinicauda, such that: (i) greater cup volume and depth were associated with larger clutch sizes, (ii) more items used during nest building were linked to improved clutch size at high elevation only, and (iii) nest wall thickness was negatively associated with hatching success. Thus, in temperate mountain ecosystems, elevation may be an important factor influencing nest-building behaviour for cavity-using vertebrates. However, the direction of the elevational.

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