The contemporary relegation of conifers mainly to cold or infertile sites has been ascribed to low competitive ability. Lusk et al. use 3-D modelling of plant architecture and structural equation modelling to compare self-shading and light interception potential of seedlings of six conifers and 12 angiosperm trees from temperate rainforests, and show that seedlings of conifers display only about half the effective leaf area of their angiosperm competitors, due to differences in specific leaf area, biomass distribution, leaf angles and self-shading. The superior light interception potential of angiosperm seedlings therefore probably contributes to the success of this lineage in productive environments where vegetation is structured by light competition.
Light partitioning within intercropping systems is mostly modelled by using the turbid medium analogy. Barillot et al. assess this approach by comparing it with a light-projective model based on 3-D plant mock-ups for contrasting grass–legume canopies (wheat–pea, tall fescue–alfalfa, tall fescue–clover). They find that light partitioning is accurately predicted by the turbid medium approach in most of the canopies studied; however, a more detailed description of the canopy is required for mixtures exhibiting marked vertical stratification and/or inter- or intraspecies overlapping of foliage.
The productivity and stability of grazed grassland rely on dynamic interactions between the sward and the animal. Combes et al. record 3-D canopy structures of swards of white clover (Trifolium repens) using an electromagnetic digitizer and adapted software, and synthesize virtual canopies in order to calculate bite mass of grazing animals and to determine effects on light interception efficiency (LIE) of the remaining sward. They find that bite mass and LIE values after grazing are more strongly affected by the initial structure of the sward than by bite form and placement.