Juan Pablo Lewis

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Monk's tonsure-like gaps develop inside gramineans and other plants. The tonsures of Spartina argentinensis originate as a result of tussock development and disturbance. As the tonsure develops the ring of tillers around it breaks down and new tussocks develop from the fragments, regenerating the grassland matrix vegetatively. The microenvironment inside(More)
Until the beginning of the twentieth century there were extensive subtropical seasonal thorny forests surrounding the Pampas grasslands of Argentina, known as the ‘Espinal’. In central Argentina there still exist relicts of the Espinal, belonging to the ‘Entrerrianense District’. These forests were never described or analyzed in detail. In 2004 we studied(More)
Amazonia and the Gran Chaco are the largest phytogeographic units of the Neotropical Region. The Forest Wedge of the Santa Fe province of Argentina is the southernmost part of the Eastern Chaco, and there are three main types of forest, 1) the mixed dense forests, 2) the Schinopsis balansae "quebrachal" and 3) the Prosopis nigra var. ragonesei forests,(More)
In several tropical and subtropical forests, plants of the understorey act as an ecological filter that differentially affects woody species regeneration. In convex sectors of the Schinopsis balansae (Anacardiaceae) forests of the Southeastern Chaco there are dense colonies of terrestrial bromeliads. These may influence forest regeneration by intercepting(More)
We examined the spatial distribution of two bromeliad species with contrasting functional traits in the understory of a xerophytic South American Chaco forest. Aechmea distichantha is a facultative terrestrial species with well-developed phytotelma and short rhizomes, whereas Bromelia serra is a strictly terrestrial species with soil-exploring roots and(More)
River floodplains have a high biological diversity that is intensely influenced by vegetation dynamics, changes in space and time scales, and the river's hydrological regime. The vegetation composition of the medium and lower Paraná River has been analyzed previously, with different approaches and criteria that cannot be compared. The aim of this study is(More)
Population characteristics of Spartina argentinensis after fire were analyzed. Field experiments were done in temporary flooded tall grassland, dominated by S. argentinensis at the Reserva Federico Wildermuth (Argentina), on burnt and non-burnt plots. The following variables were analyzed: soil seed bank, potential and real establishment of seedlings and(More)
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