994 resultados para PINUS CARIBAEA
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Tesis (Maestro en Ciencias Forestales) U.A.N.L.
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Tesis (Maestría en Ciencias Forestales) U.A.N.L.
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Tesis (Maestría en Ciencias Forestales) U.A.N.L.
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Tesis ( Maestría en Ciencias Forestales) U.A.N.L.
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Tesis (Maestría en Ciencias Forestales) UANL, 2013.
Sistema volumétrico para pinus oocarpa schiede y pinus douglasiana Martínez en el estado de Durango.
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Tesis (Maestría en Ciencias Forestales) UANL, 2013.
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Tesis (Maestría en Ciencias Forestales) UANL, 2013.
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[Tesis] (Doctor en Ciencias con Especialidad en Manejo de Recursos Naturales) U.A.N.L.
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Tesis (Doctor en Ciencias) U. A. N. L., Facultad de Ciencias Biológicas, 2007.
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Tesis (Doctorado en Ciencias con Especialidad en Manejo de Recursos Naturales) UANL, 2012.
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Tesis (Doctor en Ciencias con acentuación en Manejo y Administración de Recursos Vegetales) UANL, 2014.
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Tesis (Doctor en Ciencias con acentuación en Manejo y Administración de Recursos Vegetales) UANL, 2014.
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Inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate changes in trace element concentration in two high resolution sequences of tree rings from central Sweden. Individual annual growth increments from 18002002 to 1930-2002 were sampled from two Scots pine (Pinus sylvestris) trees from the Siljansfors Experimental Forest. The aims of the study were: to test the viability of conventional solution induction ICP-MS as a technique for investigating the multi-elemental chemistry of long tree ring sequences at annual resolution, and, to test this specifically with a view to detecting changes in elemental concentrations of Swedish tree rings contemporary with the major (and relatively proximal) Icelandic eruption of Askja (1875). It was found that despite a time consuming sample preparation process, it was possible to use conventional ICP-MS for multi-elemental analysis of a long sequence of tree rings at annual resolution. Although promising data were produced, no truly conclusive concentration anomaly could be detected in the sequence to indicate the impact of the Askja eruption on environmental chemistry. Overall findings underlined the complexity of the tree/environment interaction and the cautious approach to data interpretation essential for any dendrochemical study. (c) 2006 Elsevier Ltd. All rights reserved.
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A field monitoring study was carried out to follow the changes of fine root morphology, biomass and nutrient status in relation to seasonal changes in soil solution chemistry and moisture regime in a mature Scots pine stand on acid soil. Seasonal and yearly fluctuations in soil moisture and soil solution chemistry have been observed. Changes in soil moisture accounted for some of the changes in the soil solution chemistry. The results showed that when natural acidification in the soil occurs with low pH (3.5-4.2) and high aluminium concentration in the soil solution (> 3-10 mg l(-1)), fine root longevity and distribution could be affected. However, fine root growth of Scots pine may not be negatively influenced by adverse soil chemical conditions if soil moisture is not a limiting factor for root growth. In contrast, dry soil conditions increase Scots pine susceptibility to soil acidification and this could significantly reduce fine root growth and increase root mortality. It is therefore important to study seasonal fluctuations of the environmental variables when investigating and modelling cause-effect relationships.