All relevés were carried out during the flowering periodfor a given site, i.e. between the end of March and mid-May,from 1993 to 2000. The relevés followed the same protocolfor both C. balearicum and C. repandum using the methodsdeveloped by Godron et al. (1968). Each relevé was carriedout over a surface of 60 m2, where the Cyclamen populationappeared to be at its highest density and where there were atleast 40 Cyclamen leaves >3 cm in length. The habitat ofeach species was described using 15 quantitative and fourqualitative variables at each site. For each relevé, we recordedthe elevation (a.s.l.), aspect, slope, and topographicposition. The combination of slope and aspect allowed us tocalculate the direct annual solar radiation for the site (Gueymard,1975), whose value varies from 0 to roughly 120 ×109 kW m–2, and does not account for any cloud covervariation.In each relevé we recorded the height of the canopy, thedominant woody species (>2 m in height) and a detailedspecies list. We estimated percentage cover values for thefollowing: woody species, herbaceous species (excludingCyclamen), bryophytes, litter, bedrock and blocks >25 cm,bare soil and stones <25 cm. Human impact on the site wasestimated (Godron et al., 1968). The type of bedrock wasdetermined and a soil sample was obtained for the top 15 cmof soil. For each site the pH was measured at the laboratoryusing a Scan2 portable pH meter, by calculating a mean valuebased on three subsamples. For some statistical analyses tallwoody species were regrouped into foliage types and bedrocktypes regrouped depending on bedrock origin to simplifyanalyses.We obtained data for three climatic parameters at eachsite: mean annual precipitation (P), mean daily maximumtemperature of the warmest month (M) and mean daily minimumtemperature of the coldest month (m) (Daget, 1977).For sites in mainland France and Corsica the data wereobtained from the closest stations of the National Meteorologynetwork taking into account the altitude of the consideredsites. Reference periods were 1950–1979 for P and1969–1979 for M and m. Additional climatic data were alsoobtained for Corsica (Lombardo, 1973; Ascencio, 1983) andfor mainland France (Rousvoal, 1973; Debussche and Escarré,1983). For the sites in the Balearic Islands, the valuesof P, M and m were obtained from climatic maps(Guijarro Pastor, 1986) based on the period 1961–1980
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