Publications by authors named "Roxana Aragon"

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied.

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The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks. The decomposition of deadwood is largely governed by climate with decomposer groups-such as microorganisms and insects-contributing to variations in the decomposition rates. At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood.

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is a highly invasive East Asian tree that successfully colonizes several subtropical and temperate areas around the world. Its invasion capacity results from a widespread human use mostly in urban and periurban settings, very abundant fruit and seed production, small bird-dispersed fruits, high germination rates, resprouting capacity, fast growth rates, low herbivory levels and tolerance to a wide range of light, temperature and soil. All these traits contribute to its ability to rapidly increase in abundance, alter biodiversity, landscape ecology and limit its management.

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The impact of plant species invasions on the abundance, composition and activity of fungal decomposers of leaf litter is poorly understood. In this study, we isolated and compared the relative abundance of ligninocellulolytic fungi of leaf litter mixtures from a native forest and a forest invaded by Ligustrum lucidum in a lower mountain forest of Tucuman, Argentina. In addition, we evaluated the relationship between the relative abundance of ligninocellulolytic fungi and properties of the soil of both forest types.

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Evolutionary processes greatly impact the outcomes of biological invasions. An extensive body of research suggests that invasive populations often undergo phenotypic and ecological divergence from their native sources. Evolution also operates at different and distinct stages during the invasion process.

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Cool-season grasses establish symbioses with vertically transmitted Neotyphodium endophytes widespread in nature. The frequency of endophyte-infected plants in closed populations (i.e.

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In the last decades, South American ecosystems underwent important functional modifications due to climate alterations and direct human intervention on land use and land cover. Among remotely sensed data sets, NOAA-AVHRR "Normalized Difference Vegetation Index" (NDVI) represents one of the most powerful tools to evaluate these changes thanks to their extended temporal coverage. In this paper we explored the possibilities and limitations of three commonly used NOAA-AVHRR NDVI series (PAL, GIMMS and FASIR) to detect ecosystem functional changes in the South American continent.

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Currently biological invasions are considered one of the world's most serious conservation problems. Ligustrum lucidum is the most abundant exotic tree in secondary forest patches of montane forests of NW Argentina. We studied the determinants of success of the early stages of its life cycle in distinct habitat types, with the hope of identifying vulnerabilities that could be exploited to control the invasion.

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