Summary:Commented list of the climbing and epiphytic vascular plants of the coast of the Río de la Plata at Quilmes and Avellaneda district (Buenos Aires, Argentina). The present study includes the taxonomic richness by biological type of climbing and epiphytic plants of the coastof Quilmes district, with emphasis on the Municipal Reserve "Selva Marginal Quilmeña". A predominance of native species over exotic ones was found: 6 to 0 of epiphytes and 44 to 12 of climbers. The finding of Sicyos polyacanthus that maintains in the zone its southernmost population is highlighted. It is also relevant the presence of Pleopeltis minima, Araujia angustifolia and Philodendron undulatum that extended their distributions towards the south in recent times. These records, as well as those of several species of difficult discovery in the Río de la Plata coast, accentuate the value of the area for biodiversity conservation. The varied taxonomic composition of the area could be explained in terms of the complex history of expansion/retraction pulses of altered areas and of spontaneous vegetation, with respect to the others, and the location of the studied area within the dispersal route of the Río de la Plata fluvial system. Key words: Climbers, epiphytes, Quilmes, Río de la Plata region.Resumen: En el presente estudio se relevó la riqueza taxonómica por tipo biológico de las plantas trepadoras y epífitas de las costas del Río de La Plata en el partido de Quilmes, con énfasis en la Reserva Municipal "Selva Marginal Quilmeña". Se encontró una predominancia de especies nativas por sobre las exóticas: 6 a 0 de epifitas, 44 a 12 de trepadoras. Se destaca el hallazgo de Sicyos polyacanthus, que mantiene en la zona su población más austral conocida. También es relevante la presencia de Pleopeltis minima, Araujia angustifolia y Philodendron undulatum que extendieron sus distribuciones hacia el sur en tiempos recientes. Estos registros, así como los de varias especies de difícil hallazgo en la costa del Río de la Plata, destacan el valor del área para la conservación de la biodiversidad. La variada composición taxonómica del área se podría explicar en términos de la compleja historia de pulsos de expansión/ retracción de áreas alteradas y vegetación espontánea unas respecto de las otras, y la ubicación del área de estudio dentro de la ruta de dispersión del sistema fluvial del Plata.

Here, we studied the composition, structure and functioning of the woody vegetation of a 1000-ha area of the Central Argentine Chaco. First, we identified, through Landsat satellite image processing, three different vegetation classes: two forest types and a savanna. Each class was field surveyed to analyze the composition and structure of the woody plant community. Functioning was assessed through the enhanced vegetation index – a proxy of productivity – obtained from the MODIS sensor. The forest classes showed no differences in composition but some differences in structural attributes, particularly in the density of the dominant tree species in the area, Aspidosperma quebracho-blanco. As expected, the savanna showed less density and basal area of woody plants, with a relative high proportion of tree species seedlings and heliophilous shrubs. The forest class with less density of A. quebracho-blanco presented higher productivity. This could be related to a higher ability of the shrub layer to intercept radiation because shrubs are under an open canopy, as has been noted for early successional stages. Additionally, we found that annual mean productivity for the three classes showed a negative trend in the period 2000-2014. Our results provide valuable information since there are no studies addressing relationships between structural and functional attributes at local level in the Chaco Region.

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