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Scheiner, Samuel M; National Science Foundation; sscheine@nsf.gov; Levassor, Catherine; ;. |
We examined patterns of commonness and rarity among plant species in montane wet grasslands of Iberia. This examination is set within two contexts. First, we expanded on an earlier scheme for classifying species as common or rare by adding a fourth criterion, the ability of that species to occupy a larger or smaller fraction of its potential suitable habitats, i.e., habitat occupancy. Second, we explicated two theories, the superior organism theory and the generalist/specialist trade-off theory. The data consisted of 232 species distributed among 92 plots. The species were measured for mean local abundance, size of environmental volume occupied, percentage of volume occupied, range within Iberia, and range in Europe and the Mediterranean basin. In general,... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Commonness; Endangered species; Generalist/specialist trade-off; Geographic range; Habitat occupancy; Habitat specificity; Iberia; Local abundance; Montane grasslands; Rarity; Superior organism theory.. |
Ano: 1999 |
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Godoy-Bürki,Ana C.; Aagesen,Lone; Sajama,Jesús M.; Bravo,Silvia; Alonso-Pedano,Mariana; Ortega-Baes,Pablo. |
In this study, 34 Cactaceae species from the Calchaquíes Valleys, Argentina, were studied to determine 1) species rarity level, 2) proportion of rare species among taxonomic and ecological groups and, 3) whether rareness is consistently distributed throughout the species geographical ranges. We used a model where rarity is defined by the geographic range and the local population size to define species rarity. Rareness was not concentrated in any particular taxonomic or ecological group of Cactaceae; however 28 species were rare at some level. In most species, rarity varied across the geographical range, only five species remained consistently rare in all the surveyed populations. Six species qualified as extremely rare, all from the Cactoideae subfamily,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Geographic range; Local abundance; Extinction risk; Endemism. |
Ano: 2016 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2016000100007 |
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