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Comparative water relations of tropical alpine plants / G. Goldstein

Public in Tropical alpine environments : plant form and function / Philip Rundel (1994) Titre : Comparative water relations of tropical alpine plants Type de document : texte imprimé Auteurs : G. Goldstein, Auteur ; Philip Rundel, Auteur Importance : pp. 61-76 Langues : Anglais (eng) Résumé : "In tropical alpine regions drought may be the most important seasonal factor in an environment that otherwise lacks significant seasonality (see Smith, Chapter 1). In many of these regions diurnal cycles of physiological drought associated with low soil temperatures may be superimposed on the seasonal changes in soil moisture. From studies of cold temperate zone plants, particularly conifers (Kaufmann 1975, 1977; Running & Reid 1980), it is known that even in soils near field capacity, water uptake by roots may be severely impaired by low soil temperatures (0–5 °C). This high root resistance to water uptake may extend through spring and into early summer in temperate zone coniferous forests with persistent snow cover. In arctic regions, physiological drought may extend throughout the entire summer if the roots are situated above a permafrost layer (Goldstein 1981). In the tropical alpine zone, where snow cover is not persistent and permafrost does not exist, the potential for physiological drought is nevertheless present. The risk is especially great during the early morning hours when soil temperatures in the root zone are near freezing and potential transpiration is high due to high solar radiation loads. The simultaneous occurrence of low water availability in the absolute sense on a seasonal basis, and in the physiological sense on a diurnal basis, complicates the analysis of drought resistance mechanisms in tropical alpine plants. It also provides an excellent opportunity to study adaptations to drought along both altitudinal and geographical gradients of relative importance of diurnal versus seasonal drought." (source : auteurs) Type de publication : article de livre Référence biblio : Goldstein G., Rundel P., 1994 - Comparative water relations of tropical alpine plants. In : 1994 - Tropical alpine environments : plant form and function. Cambridge University Press, 61-76. ID PMB : 7616 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=7616

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Population dynamics and flowering in a hawaiian alpine rosette plant, Argyroxiphium sandwicense / Philip Rundel

Public in Tropical alpine environments : plant form and function / Philip Rundel (1994) Titre : Population dynamics and flowering in a hawaiian alpine rosette plant, Argyroxiphium sandwicense Type de document : texte imprimé Auteurs : Philip Rundel, Auteur ; M.S. Witter, Auteur Importance : pp. 295-306 Langues : Anglais (eng) Catégories : [ZG] Hawaï Résumé : "A notable feature of tropical alpine floras in many parts of the world is the presence of rosette plants with monocarpic growth habits. These long-lived perennials flower only once in their lives, producing a giant inflorescence with large numbers of flowers before the parent plant dies. In the South American páramos of Venezuela, species of Espeletia (Asteraceae) provide classic examples of this life-form (Cuatrecasas 1986; Berry & Calvo, Chapter 13)). Giant species of Afroalpine Lobelia (Campanulaceae) reach to 5–6 m in height when flowering before dying, and form one of the most spectacular elements of the flora of the tropical African highlands (Mabberley 1974; Young, Chapter 14). On Tenerife in the Canary Islands, two alpine species of Echium (Boraginaceae) have also evolved rosette growth forms and a monocarpic habit (Carlquist 1974). In each of these groups, the monocarpic rosette plants have evolved from polycarpic ancestors with a shrubby growth form. Argyroxiphium sandwicense (Asteraceae) provides another well-known example of the evolution of a monocarpic rosette plant in a tropical alpine environment. The genus Argyroxiphium, with five species, is one of three genera of Hawaiian tarweeds that have evolved from a monophyletic North American origin (Carr 1985; Witter & Carr 1988; Baldwin et al. 1991). This group displays a remarkable diversity of growth forms and adaptive morphologies. Monocarpic rosette plants have evolved not only in species of Argyroxiphium in bog and in alpine habitats, but also in Wilkesia gymnoxiphium, a stalked rosette plant in scrub and open forest habitats." (source : auteurs) Type de publication : article de livre Référence biblio : Rundel P., Witter M.-S., 1994 - Population dynamics and flowering in a hawaiian alpine rosette plant, Argyroxiphium sandwicense. In : 1994 - Tropical alpine environments : plant form and function. Cambridge University Press, 295-306. ID PMB : 7605 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=7605

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Tropical alpine climates / Philip Rundel

Public in Tropical alpine environments : plant form and function / Philip Rundel (1994) Titre : Tropical alpine climates Type de document : texte imprimé Auteurs : Philip Rundel, Auteur Importance : pp. 21-44 Langues : Anglais (eng) Résumé : "Ecological interest in climates of the tropical alpine regions of the world dates back perhaps to the early travels of La Condamine in Ecuador in the mid-19th century, but more dramatically to the remarkable explorations of Alexander von Humboldt in the northern Andes, Central America and Mexico from 1799 to 1804. His contributions to science from these travels, which encompassed geography, biology, geology, climatology, anthropology and other subjects, filled 30 volumes (von Humboldt 1807–39), and had a tremendous influence on the intellectual and economic development of Latin America in the 19th century. No less an authority than Simon Bolivar once remarked, ‘Baron Humboldt did more for the Americas than all of the conquistadors’ (Von Hagen 1948). The scientific studies of von Humboldt served as the foundation of the modern science of biogeography, and his climatological observations in the Andes and on the Mexican volcanoes played a major role in the development of his ideas. Another notable advance in scientific knowledge of alpine climatology in tropical mountain regions came not from a typical scientist at all but from the noted European alpinist, Edward Whymper. Whymper, who had been the first man to scale the Matterhorn in the Swiss Alps in 1865, came to Ecuador in 1879 to attempt climbs of Chimborazo and other high volcanoes of that region. He was spectacularly successful not only in these ascents, but in the wealth of ecological and climatological data which he collected and published (Whymper 1892)." (source : auteur) Type de publication : article de livre Référence biblio : Rundel P., 1994 - Tropical alpine climates. In : 1994 - Tropical alpine environments : plant form and function. Cambridge University Press, 21-44. ID PMB : 7618 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=7618

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Tropical alpine environments : plant form and function / Philip Rundel (1994)

Public Titre : Tropical alpine environments : plant form and function Type de document : texte imprimé Auteurs : Philip Rundel, Directeur de publication ; Alan Smith, Directeur de publication ; F.C. Meinzer, Directeur de publication Editeur : Cambridge University Press Année de publication : 1994 Importance : 376 p. ISBN/ISSN/EAN : 978-0-511-55147-5 Langues : Anglais (eng) Type de publication : livre Référence biblio : Rundel P. & Smith A.-P. & Meinzer F.-C. (coord.), 1994 - Tropical alpine environments : plant form and function. Cambridge University Press, 376 p. ID PMB : 1345 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=1345

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Cote	Localisation	Disponibilité
R29000110	Brest	Exclu du prêt

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