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5 resultados encontrados para: AUTOR: Lloyd, J.
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1.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Taxonomy of Gila in the lower Colorado River basin of Arizona and New Mexico
Page, Lawrence M. (coaut.) ; Baldwin, Carole C. (coaut.) ; Espinosa Pérez, Héctor (coaut.) ; Findley, Lloyd T. (coaut.) ; Gilbert, Carter R. (coaut.) ; Hartel, Karsten E. (coaut.) ; Lea, Robert N. (coaut.) ; Mandrak, Nicholas E. (coaut.) ; Schmitter Soto, Juan Jacobo (coaut.) ; Walker Jr., H. Jesse (coaut.) ;
Contenido en: Fisheries Vol. 42, no. 9 (September 2017), p. 456-460 ISSN: 1548-8446
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

A publication by Moran et al. (2017) on species of Gila in the Gila River basin appeared after our paper was in press. The goal of their study was to test whether previously used morphological characters could differentiate G. robusta, G. intermedia, and G. nigra from one another, and if not, to discover methods that are better suited for identifying these species based on morphology. The study found that the variables proposed by Rinne (1976) and Minckley and DeMarais (2000) could not be used to identify individuals to species but that geometric morphometrics could be used to differentiate the species. The study used canonical variate analysis, which requires a priori designation of groups and maximizes differences among these groups. Because of this, and noting the clear effect of geographic location on morphological variation in Gila, the authors concluded that “it is difficult to decide if the three species should be retained as valid, recognized as a single species, or considered as subspecies.” We view this study, while interesting and well conceived, as another that failed to recognize populations of G. robusta as belonging to more than one species.


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Resumen en: Inglés |
Resumen en inglés

We summarise the contemporary carbon budget of South America and relate it to its dominant controls: population and economic growth, changes in land use practices and a changing atmospheric environment and climate. Component flux estimate methods we consider sufficiently reliable for this purpose encompass fossil fuel emission inventories, biometric analysis of old-growth rainforests, estimation of carbon release associated with deforestation based on remote sensing and inventories, and agricultural export data. Alternative methods for the estimation of the continental-scale net land to atmosphere CO2 flux, such as atmospheric transport inverse modelling and terrestrial biosphere model predictions, are, we find, hampered by the data paucity, and improved parameterisation and validation exercises are required before reliable estimates can be obtained. From our analysis of available data, we suggest that South America was a net source to the atmosphere during the 1980s (~ 0.3–0.4 Pg C a−1) and close to neutral (~ 0.1 Pg C a−1) in the 1990s. During the latter period, carbon uptake in old-growth forests nearly compensated for the carbon release associated with fossil fuel burning and deforestation.

Annual mean precipitation over tropical South America as inferred from Amazon River discharge shows a long-term upward trend. Although, over the last decade dry seasons have tended to be drier, with the years 2005 and 2010 in particular experiencing strong droughts. On the other hand, precipitation during the wet seasons also shows an increasing trend. Air temperatures have also increased slightly. Also with increases in atmospheric CO2 concentrations, it is currently unclear what effect these climate changes are having on the forest carbon balance of the region. Current indications are that the forests of the Amazon Basin have acted as a substantial long-term carbon sink, but with the most recent measurements suggesting that this sink may be weakening. Economic development of the tropical regions of the continent is advancing steadily, with exports of agricultural products being an important driver and witnessing a strong upturn over the last decade.


3.
Libro
Statistical analysis of categorical data / Chris J. Lloyd
Lloyd, Chris J. ;
New York : John Wiley and Sons , c1999
Clasificación: 519.535 / L5
Bibliotecas: Villahermosa
Cerrar
SIBE Villahermosa
ECO050001159 (Disponible)
Disponibles para prestamo: 1

4.
Libro
*En proceso técnico. Solicítelo con el bibliotecario(a) de SIBE-San Cristóbal
Plant genetic conservation: the in situ approach / edited by N. Maxted, B.V. Ford-Lloyd, and J.G. Hawkes
Maxted, Nigel (ed.) ; Ford-Lloyd, Brian (coed.) ; Hawkes, J. G. (coed.) (1915-2007) ;
London, England : Chapman & Hall , c1997
Clasificación: 631.523 / P3
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
36289-20 (Disponible)
Disponibles para prestamo: 1
Nota: En proceso técnico. Solicítelo con el bibliotecario(a) de SIBE-San Cristóbal

5.
Libro
Demography and ecology of a declining snowshoe hare population / Lloyd B. Keith, John R. Cary ...[et al.]
Keith, Lloyd B. ; Cary, John R. (coaut.) ; Rongstad, Orrin J. (coaut.) ; Brittingham, Margaret C. (coaut.) ;
Bethesda, Maryland, United States : The Wildlife Society , 1984
Clasificación: F/591.505 / W5/90
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
SAF003025 (Disponible)
Disponibles para prestamo: 1