Does shade improve light interception efficiency? A comparison among seedlings from shade-tolerant and -intolerant temperate deciduous tree species

• Here, we tested two hypotheses: shading increases light interception efficiency (LIE) of broadleaved tree seedlings, and shade-tolerant species exhibit larger LIEs than do shade-intolerant ones. The impact of seedling size was taken into account to detect potential size-independent effects on LIE. LIE was defined as the ratio of mean light intercepted by leaves to light intercepted by a horizontal surface of equal area. • Seedlings from five species differing in shade tolerance (Acer saccharum, Betula alleghaniensis, A. pseudoplatanus, B. pendula, Fagus sylvatica) were grown under neutral shading nets providing 36, 16 and 4% of external irradiance. Seedlings (1- and 2-year-old) were three-dimensionally digitized, allowing calculation of LIE. • Shading induced dramatic reduction in total leaf area, which was lowest in shade-tolerant species in all irradiance regimes. Irradiance reduced LIE through increasing leaf overlap with increasing leaf area. There was very little evidence of significant size-independent plasticity of LIE. • No relationship was found between the known shade tolerance of species and LIE at equivalent size and irradiance

A method for 3D reconstruction of tree canopy volume photographs: assessment from 3D digitised plants

10 tables Annexe 2 p.*UMR PIAF INRA-UBP Site de Crouelle 234 avenue du Brézet 63039 Clermont-Ferrand Cedex2 (FRA) Diffusion du document : UMR PIAF INRA-UBP Site de Crouelle 234 avenue du Brézet 63039 Clermont-Ferrand Cedex2 (FRA)absen

Tree analyzer: a software to compute tree structure parameters from photographs

INRA PIAF UMR-UBP Sire de Crouelle 234 Avenue du Brézet 63039 Clermont-Ferrand (FRA) Diffusion du document : INRA PIAF UMR-UBP Sire de Crouelle 234 Avenue du Brézet 63039 Clermont-Ferrand (FRA)absen