Systematic Diversity of the Family Poaceae (Gramineae) in Chileглава из книги
Аннотация: The role of Systematics in studies of biodiversity is essential to a variety of studies, including species conservation, extinction, biodiversity hotspots, bio-prospecting and ecosystem function (Alroy, 2002; Scotland & Wortley, 2003; Smith & Wolfson, 2004; Wilson, 2000). The analysis of the biodiversity as well as the analysis of the distribution of species richness at different levels (national, regional), the distribution of the endemic species, the detection of areas whose preservation is necessary and many other topics related to the conservation of the biodiversity requires an important collection effort, so that the organized databases constructed by the herbaria become as comprehensive as possible. Herbarium specimens represent a rich source of information for botanists and ecologists, even though data based on herbaria collections have many limitations, since they are geographically and seasonally biased, and taxonomically incomplete (Crawford & Hoagland, 2009; Delisle et al., 2003; Fuentes et al., 2008; Funk & Richardson, 2002; Ponder et al., 2001). Moreover, it has been established that there is a tendency to a decline in the number of specimens of vascular plants collected in the last years (Prather et al., 2004), although taxonomists are aware that there are still many undescribed species (Smith & Wolfson, 2004). In order to know how many species of grasses exist in Chile, as well as their identity and taxonomic distribution, this chapter provides a checklist of the family Poaceae in Chile, taking into account the nomenclatural changes recently proposed. Moreover, we analyze the completeness of the inventory of the family represented in two of the most important national herbaria. Grasses (Poaceae or Gramineae) are the fifth most diverse family among the flowering plants or Angiosperms and the second most diverse family among the Monocotyledons. Poaceae comprises about 10,000 species in approximately 700 genera (Clayton & Renvoize, 1986; Tzvelev, 1989; Watson & Dallwitz, 1992). Recent evidence suggests that grasses had already diversified during the Cretaceous. The evidence came from phytolith analysis (Prasad et al., 2005), tiny crystals of silica formed in the epidermal cells of leaves or floral bracts of grasses and other plants. The discovery of grass phytoliths in coprolites of titanosaurid sauropods that lived in India 65 to 71 million years ago (Prasad et al., 2005), suggested that grasses and dinosaurs coevolved (Piperno & Sues, 2005). Phylogenetic approach to reveal the evolutionary history of grasses in a biogeographical context suggests that Poaceae originated in the African or South American regions of Gondwana during the late Cretaceous (Bouchenak-Khelladi et al., 2010).
Год издания: 2011
Авторы: L. Victor, Ana Juan, Clodomiro Marticorena, Gloria Rojas
Источник: InTech eBooks
Ключевые слова: Plant Taxonomy and Phylogenetics, Plant Diversity and Evolution, Mediterranean and Iberian flora and fauna
Другие ссылки: InTech eBooks (PDF)
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BiblioBoard Library Catalog (Open Research Library) (HTML)
InTech eBooks (HTML)
BiblioBoard Library Catalog (Open Research Library) (HTML)
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