Grégoire Vincent

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BACKGROUND AND AIMS The phenotypic plasticity of leaf life span in response to low resource conditions has a potentially large impact on the plant carbon budget, notably in evergreen species not subject to seasonal leaf shedding, but has rarely been well documented. This study evaluates the plasticity of leaf longevity, in terms of its quantitative(More)
BACKGROUND AND AIMS Morphogenetic plasticity may be as important as physiological plasticity in determining plant adaptability to changing environmental conditions. This study examines the importance of crown plasticity of trees in stands. METHODS A three-dimensional forest simulator is used to explore the impact of crown shape plasticity on tree growth.(More)
While theoretical allometric models postulate universal scaling exponents, empirical relationships between tree dimensions show marked variability that reflects changes in the biomass allocation pattern. As growth of the various tree compartments may be controlled by different functions, it is hypothesized that they may respond differently to factors of(More)
Trees outside closed forest stands differ in the relation between stem diameter, height and crown volume from trees that grew with neighbours close by. Whether this plasticity in tree shape varies between species in relation to their light requirement is unknown. We purposefully sampled 528 trees ranging 5–100 cm diameter at breast height growing in a range(More)
Ambrosia artemisiifolia is a common weed in Canada and it is one of the most important source of aero-allergenic pollen in the north-eastern part of North America. It is a problem mostly along roads in urban or suburban areas. It is easily controlled by herbicides but their use is increasingly restricted because of environmental considerations. Therefore,(More)
Airborne laser scanning provides continuous coverage mapping of forest canopy height and thereby is a powerful tool to scale-up above-ground biomass (AGB) estimates from stand to landscape. A critical first step is the selection of the plot variables which can be related to light detection and ranging (LiDAR) statistics. A universal approach was previously(More)
A new method to determine the concentration of germanium in Si(1-x) Ge(x) single crystals is presented. It is based on extinction distance measurements by means of convergent beam electron diffraction (CBED). The two-beam condition CBED intensity oscillation (the so-called rocking curve) is measured for the 004 diffracted beam and compared with a numerical(More)
BACKGROUND AND AIMS Morphological variation in light-foraging strategies potentially plays important roles in efficient light utilization and carbon assimilation in spatially and temporally heterogeneous environments such as tropical moist forest understorey. By considering a suite of morphological traits at various hierarchical scales, we examined the(More)