Data on vascular plant species composition along two elevation gradients in the high Andes of central Chile (33°S).

The results of a survey of vascular plant species along two elevational gradients in the high Andes of central Chile (33°S) are reported. Vascular plant species were recorded in 12 and 15 plots of 1600 m² set up to be permanent, distributed at intervals of 100 m elevation along two elevational gradients, one in the La Parva (2500-3600 m a.s.l.) and a second in the Valle Nevado (2300-3700 m a.s.l.) area, Metropolitan Region of Santiago. All plots were square in shape except for one that was divided into two sections due to a landslide on the slope. Plots cover subalpine vegetation above the Kageneckia angustifolia treeline and the entire alpine belt to the upper limit of consistent vascular plant vegetation. The presence of each species in the individual plots is given along with location data for the plots, including georeferences, altitude, and sampling dates. Images of the study area are included. Scientific names, families, life forms, and native/non-native status are provided for the 168 taxa (167 species with one represented by two subspecies) recorded. Data on temperature and relative humidity for three sites in the general study area are included. The reported plot data will be useful for detailed studies on patterns of diversity (e.g., phylogenetic diversity, functional diversity) along elevational gradients in high mountains and for monitoring the upward shift of non-native species. Importantly, the data set provides a solid basis for detecting changes in species composition under ongoing climate change in the southern Andes, an area that has received limited attention to date but is highly relevant given instrumental evidence of rapid warming.