Fig 1.
Location of the South American lomas vegetation (red dots), the study area with the location of the sampling points (yellow points) and the location of the SENAMHI meteorological station (black cross).
Precipitation and temperature climatologies for Lomas de Lachay are the average values for the period 2000–2010 (SENAMHI data). The digital elevation model was retrieved from Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global (https://lta.cr.usgs.gov/SRTM1Arc).
Table 1.
Plant community characteristics and climate data recorded between 1998 and 2001.
ENSO phases are described in methods. Ranges of values are shown in brackets.
Fig 2.
Floristic composition for each of the 15 sampling campaigns.
Only the top 20 species according to their importance value index (IVI) are shown (see methods).
Fig 3.
Changes in species composition.
Biplot of the detrended correspondence analysis (DCA) showing species in cross and the different field sampling campaigns in dots (red = the El Niño event, blue = the La Niña event, green = normal conditions, according to NOAA [39]). For clarity, only the most important species are shown, based on the importance value index (IVI).
Fig 4.
Changes in plant community characteristics.
Boxplots of alpha diversity, vegetation cover and density for each sampling campaign between 1998 and 2001 based on 31 plots. A) Boxplots showing temporal changes within years. Months significantly different within each year have different letters (paired t-test with Bonferroni correction, p-value < 0.05). B) Boxplots showing temporal changes for the same month in different years. For each month, the year with values significantly different from other years have different letters (paired t-test with Bonferroni correction, p-value < 0.05). Data has been log-transformed.
Fig 5.
Temporal changes in the seasonality index.
The percentage represents the range between the driest and most humid month (February and August respectively) divided by the most humid month (see methods).