Contribution
Freshwater diatom biogeography
Kociolek, John P.; Spaulding, Sarah A.
Nova Hedwigia Band 71 Heft 1-2 (2000), p. 223 - 241
138 références bibliographiques
publié: Sep 3, 2000
ArtNo. ESP050007101016, Prix: 29.00 €
Abstract
Current diatom research is predominantly based on a paradigm ofa cosmopolitan geographic distribution of freshwater diatoms, a paradigm that has been almost without challenge. The accepted worldview of diatom biogeography has been based on dispersal and ecological selection; however, it appears that such a perspective is not fully supported by observations. Studies of the regional distribution of diatoms, herbarium voucher material, local diatom populations, and eolian dispersal do not support cosmopolitanism. The distribution of diatoms may have more to do with historical distributions than with ecological tolerances. We advocate a phylogenetic view of biogeography, including the importance of historical distributions and evolutionary lineages. While a number of taxa may be confirmed to be cosmopolitan, we predict that they are few compared to the total number of species. Furthermore, anthropogenic impacts, including transport mechanisms and alterations of environments, may be responsible for a substantial number of true cosmopolitan taxa. As diatom distributions become better known, forgotten and overlooked historical explanations for distributions will have implications for all areas of diatom research including: taxonomy, systematics, ecology, paleolimnology, biomonitoring and paleontology.
Mots-clefs
diatom research • freshwater diatoms • ecological tolerance • biomonitoring • taxonomy