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Leaf gas exchange in canopy species of a Venezuelan cloud forest
(Biotropica 41(6): 659-664, 2009-11)
Tropical cloud forests are considered humid ecosystems with frequent cloud cover down to the ground surface. However, seasonal variation in precipitation may induce
short-term water stress. For canopy leaves, this water ...
Coupling soil water and shoot dynamics in three grass species: A spatial stochastic model on water competition in Neotropical savanna
(Ecological Modelling 220: 2734 - 2743, 2009-10-24)
Savannas are ecosystems known for their high environmental and economic value. They cover at least 20% of the global land surface and, in some cases, can act as a boundary between tropical rainforest and deserts.Water is ...
Low temperature resistance in saplings and ramets of Polylepis sericea in the Venezuelan Andes
(Acta Oecologica 35(5): 610–613, 2009-10)
The frequent occurrence of all year-round below zero temperatures in tropical high mountains constitutes a most stressful climatic factor that plants have to confront. Polylepis forests are found well above
the continuous ...
Interception of water by pastures of Pennisetum clandestinum Hochst. ex Chiov. and Melinis minutiflora Beauv
(Agricultural and Forest Meteorology 149: 1616-1620, 2009-10)
The conversion of montane cloud forests into pastures for grazing cattle is the main cause of important impacts on rivers and streams in most of the Andes. In order to evaluate the effects of vegetation changes we need to ...
Sensitivity of soil restoration indicators during paramo succession in the high tropical Andes: chronosequence and permanent plot approaches
(Restoration Ecology 17(5): 619-628, 2009-09)
The aim of this study was to analyze indicators of soil restoration during secondary succession in a heterogeneous
valley in the high tropical Andes. A combination of chronosequence and permanent plot methods was used to ...
Un método participativo para el mapeo de fincas y la recolección de estadísticas agrícolas aplicable a varias escalas espaciales
(Interciencia 34(7): 479-486, 2009-07-28)
Se diseñó y probó un método para el mapeo participativo de fincas y la recolección de información agrícola, en el cual los
pobladores delimitan los linderos de sus fincas y realizan su sectorización interna directamente ...
Hipersensibilidad tipo IV al Níquel y su relación con restauraciones metálicas en la cavidad oral.
(Acta odontol. venez v.47 n.1 Caracas mar. 2009, 2009-03-30)
A fin de determinar la prevalencia de hipersensibilidad tipo IV al contacto con níquel (Ni) y su
relación con una historia clínica de alergia positiva, el uso de prótesis parcial removible (PPR) y la
presencia de restauraciones ...
Estudio del consumo alimentario a partir de la encuesta de presupuestos familiares. El caso del Distrito Federal (Venezuela), 2004-2005
(2009-02-25)
El objetivo de este trabajo es analizar el comportamiento del consumidor venezolano en general, y del habitante de la capital de Venezuela, en particular, a partir de información correspondiente a datos de corte transversal ...
Ecosistemas de Los Andes del Norte y Centro. Bolivia, Colombia, Ecuador, Perú y Venezuela.
(Secretaría General de la Comunidad Andina, Programa Regional ECOBONA-Intercooperation, CONDESAN-Proyecto Páramo Andino, Programa BioAndes, EcoCiencia, NatureServe, IAvH, LTA-UNALM, ICAE-ULA, CDC-UNALM, RUMBOL SRL. Lima. pp.7-9, 2009)
Los Andes del Norte y Centro o Andes Tropicales cubren una extensión de 1´542.644 Km desde el Oeste de Venezuela hasta la frontera entre Bolivia, Chile y Argentina. Considerados como la región de mayor riqueza y diversidad ...