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The ecology, distribution and conservation status of Myrcianthes coquimbensis : a globally endangered endemic shrub of the Chilean Coastal Desert

Autores:

García-Guzman, P., Loayza, A., Carvajal, D., Letelier, L., & Squeo, F.

Resumen:

The current distribution of M. coquimbensis extends along 82.8 km of the Chilean coast, where the species is mainly threatened by habitat loss. Only 13% of the individuals flowered during 2010, and 66% of these plants lost their entire flower crop due to desiccation. Few seeds (7.5%) were lost to post-dispersal seed predation. The populations are composed mainly of adult plants (70% of the individuals), and little to no recruitment was observed.

Año: 2012

Palabras claves: Atacama Desert, Chile, conservation biology, habitat loss, Myrtaceae, restricted-range species,

Referencia APA: García-Guzman, P., Loayza, A., Carvajal, D., Letelier, L., & Squeo, F. (2012). The ecology, distribution and conservation status of Myrcianthes coquimbensis: a globally endangered endemic shrub of the Chilean Coastal Desert. Plant Ecology & Diversity, 5(2), 197-204.

Progress in creating a joint research agenda that allows networked long-term socio-ecological research in southern South America: Addressing crucial technological and human capacity gaps limiting its application in Chile and Argentina.

Autores:

Anderson, C., Celis-Diez, J., Bond, B., Martínez Pastur, G., Little, C., & Armesto, J., Ghersa, C., Austin, A., Schlichter, T., Lara, A., Carmona, M., Chaneton, E.J., Gutierrez, J.R.,et al.

Resumen:

Since 1980, more than 40 countries have implemented long-term ecological research (LTER) programs, which have shown their power to affect advances in basic science to understand the natural world at meaningful temporal and spatial scales and also help link research with socially relevant outcomes. Recently, a disciplinary paradigmatic shift has integrated the human dimensions of ecosystems, leading to a long-term socio-ecological research (LTSER) framework to address the world's current environmental challenges. A global gap in LTER/LTSER only exists in the latitudinal range of 40–60°S, corresponding to Argentina and Chile's temperate/sub-Antarctic biome. A team of Chilean, Argentine and US researchers has participated in an ongoing dialogue to define not only conceptual, but also practical barriers limiting LTER/LTSER in southern South America. We have found a number of existing long-term research sites and platforms throughout the region, but at the same time it has been concluded an agenda is needed to create and implement further training courses for students, postdoctoral fellows and young scientists, particularly in the areas of data and information management systems. Since LTER/LTSER efforts in Chile and Argentina are incipient, instituting such courses now will enhance human and technical capacity of the natural science and resource community to improve the collection, storage, analysis and dissemination of information in emerging LTER/LTSER platforms. In turn, having this capacity, as well as the ongoing formalization of LTER/LTSER programs at national levels, will allow the enhancement of crucial collaborations and comparisons between long-term research programs within the region and between hemispheres and continents. For Spanish version of the entire article, see Online Supporting Information (Appendix S1).

Año: 2012

Palabras claves: environmental monitoring; information management; long-term ecological research; LTER; LTSER; science policy; socio-ecology

Referencia APA: Anderson, C., Celis-Diez, J., Bond, B., Martínez Pastur, G., Little, C., & Armesto, J., Ghersa, C., Austin, A., Schlichter, T., Lara, A., Carmona, M., Chaneton, E.J., Gutierrez, J.R., et al. (2012). Progress in creating a joint research agenda that allows networked long-term socio-ecological research in southern South America: Addressing crucial technological and human capacity gaps limiting its application in Chile and Argentina. Austral Ecology, 37(5), 529-536.

Leaf morphological and genetic divergence in populations of Drimys (Winteraceae) in Chile.

Autores:

Jara-Arancio, P., Carmona, M., Correa, C., Squeo, F., & Arancio, G.

Resumen:

The genus Drimys is distributed in Chile from semiarid zones to sub-Antarctic forests; there are three species of this tree, D. andina, D. confertifolia and D. winteri, the latter with varieties chilensis and winteri. Northern populations are found in small disjunct natural refuges, specifically mountain cloud forests and the bottom of ravines. The size and continuity of populations are greater in the south, where wetter conditions prevail. Morphological differences between populations have been observed, particularly between the northern populations of Fray Jorge and Talinay. This observation, led to the following questions: a) what is the level of morphological and genetic divergence among the populations of Drimys in Chile? and b) do the populations from Fray Jorge/Talinay, currently classified as D. winteri var. chilensis, differ genetically from the other populations of this variety? To answer these questions, we collected leaf samples from 37 populations of all Chilean Drimys, performed leaf morphology analysis and estimated genetic divergence using RAPD markers. We found a high degree of leaf morphological and genetic divergence between the populations of Fray Jorge/Talinay and the other Chilean species of Drimys. The morphological and genetic divergence among varieties of D. winteri was greater than that among the species of Drimys, which may indicate problems with their taxonomic classification.

Año: 2012

Palabras claves: Drimys; RAPD; Fray Jorge/Talinay; Divergence

Referencia APA: Jara-Arancio, P., Carmona, M., Correa, C., Squeo, F., & Arancio, G. (2012). Leaf morphological and genetic divergence in populations of Drimys (Winteraceae) in Chile. Genetics And Molecular Research, 11(1), 229-243.

No evidence of a trade-off between drought and shade tolerance in seedlings of six coastal desert shrub species in north-central Chile.

Autores:

Martínez-Tillería, K., Loayza, A., Sandquist, D., & Squeo, F.

Resumen:

We found species-specific differences in the temporal pattern of mortality. Water and/or light levels affected seedling survival of all species, excluding C. chilensis. Relative growth rate (RGR) increased in low-light conditions in C. chilensis and P. revolutus, but otherwise did not vary in response to differences in either light or water, independently or to their interaction. Across species, the effect of water on specific leaf area (SLA) was inconsistent, increasing both in drought conditions (C. chilensis) and in treatments with supplemental water (S. cumingii). Additionally, SLA tended to increase with decreasing light levels for most species (F. thurifera, H. parvifolius, C. chilensis). In our study, only F. thrurifera and C. chilensis showed changes in leaf mass ratio (LMR) and only with respect to light levels; specifically, LMR tended to increase with decreasing light level. Biomass allocation was independent of light and water for all species except F. thurifera, which showed an increase in root biomass in drought conditions.

Año: 2012

Palabras claves: Atacama desert; Biomass allocation; Centaurea chilensis ; Encelia canescens ; Flourensia thurifera ; Haplopappus parvifolius ; LMR ; Pleocarphus revolutus ; RGR ; Seedling performance; Senna cumingii ; SLA

Referencia APA: Martínez-Tillería, K., Loayza, A., Sandquist, D., & Squeo, F. (2012). No evidence of a trade-off between drought and shade tolerance in seedlings of six coastal desert shrub species in north-central Chile. J Veg Sci, 23(6), 1051-1061.

Application of high hydrostatic pressure to aloe vera (Aloe barbadensis Miller) gel: Microbial inactivation and evaluation of quality parameters

Autores:

Vega-Gálvez, A., Giovagnoli, C., Pérez-Won, M., Reyes, J., Vergara, J., & Miranda, M. et al.

Resumen:

High hydrostatic pressure (HHP) is an innovative technology which minimizes loss of physicochemical and nutritional quality matching consumer demands for fresh-like foods. The aim of this study was to investigate the effect of high hydrostatic pressure (300, 400 and 500 MPa/1, 3 and 5 min) on microbial inactivation and quality parameters of A. vera gel after 60 days of storage. Shelf life was determined successfully by fitting experimental microbial data to the modified Gompertz equation for samples treated at 300 MPa/1 min. The samples treated at 400 and 500 MPa during 1, 3 and 5 min presented undetectable levels of microorganisms' counts. Based on microbiological results, the analysis of quality attributes was focused on the effects of HHP (300, 400 and 500 MPa) during 5 min of processing. Antioxidant activity, which was analyzed by means of total polyphenols content and DPPH-radical scavenging activity, showed a maximum value at 500 MPa. At 400 MPa, vitamin C showed the maximum retention (93%) and vitamin E increased the initial value of the gel. An increase of polysaccharides at 500 MPa also affected the gel firmness. Differences in surface color were also observed. Based on results, application of 500 MPa during 5 min may be successfully used to preserve main quality attributes of A. vera gel.

Año: 2012

Palabras claves: High hydrostatic pressure; Quality indices; Microbial growth; Shelf life; A. vera gel

Referencia APA: Vega-Gálvez, A., Giovagnoli, C., Pérez-Won, M., Reyes, J., Vergara, J., & Miranda, M. et al. (2012). Application of high hydrostatic pressure to aloe vera (Aloe barbadensis Miller) gel: Microbial inactivation and evaluation of quality parameters. Innovative Food Science & Emerging Technologies, 13, 57-63