DISTRIBUCIÓN DE UNA LEÑOSA EXÓTICA INVASORA EN UN SISTEMA DE MONTAÑA ¿OCUPAN COTONEASTER FRANCHETII Y LA LEÑOSA NATIVA POLYLEPIS AUSTRALIS (ROSACEAE) HÁBITATS SIMILARES?

Background and aims: Invasive plants succeeding at high-elevation ecosystems threaten biodiversity and ecosystem services conservation in mountain protected areas. In this study we assessed whether an exotic woody species, Cotoneaster franchetii Bois, responds to mountain environmental heterogeneity in a similar way to the dominant coexisting native woody species, Polylepis australis Bitter, or if it instead occupies a greater variety of habitats aided by the wide environmental tolerance expected for mountain invaders. M&M: We recorded C. franchetii and P. australis occurrence and cover in 120 square plots between 1200 and 2200 masl, inside and surrounding "Quebrada del Condorito" National Park and "Pampa de Achala" natural reserve (Córdoba, Argentina). We compared both species' distribution and its relationship with vegetation and topograpy. Results: Each species dominated at different elevations. However, at local scale, both species were more frequent in plots placed at valleys and south-facing steep slopes, with less cover of tussock grassland and more rock cover. Contrary to the native species, C. franchetii cover was unaffected by vegetation and topographic characteristics. Conclusions: High occurrence and no restrictions for increasing cover once established suggest a high spread potential of C. franchetii in these mountains. Polylepis australis is seemingly at risk since both species share habitat preferences. Wide environmental tolerance would not only trigger upward expansion of invasive species in mountains but also towards natural vegetation. [ABSTRACT FROM AUTHOR]