The decline in mixed canopies was associated with an increase in the abundance of Sargassum spp., replacing a more diverse canopy of Scytothalia doryocarpa and several other large fucoids.
For well-mixed canopies, theoretical isolines of light interception have been derived from equation (4) for different values of α, i.e. ratios of K1/ K1/
The above results show that when canopy closure and species interactions begin, the level of light sharing was not only determined by the species LAI and foliage inclination as can be estimated for well-mixed canopies.
The two last groups, for which the contribution to total LAI exceeded 60%%, showed divergences between computed values of light sharing and the theoretical approach that assumes well-mixed canopies (Fig. 3F, slope of the linear regression = 0.97, R = 0.42).
At 300 DD (Fig. 3A), computed values of light sharing were close to the theoretical isoline estimated for well-mixed canopies (Fig. 3B, slope of the linear regression = 0.99, R = 0.97).
The turbid medium approach, extended to well-mixed canopies, was used as a framework for assessing the effects of leaf area index (LAI) and mean leaf inclination on light sharing.
Deviations between computed values of light sharing and the theoretical approach, which assumes well-mixed canopies, were then studied in regard to the relative height of the component species (wheat/pea height, Fig. 4).
The shrub also has a disturbing tendency to do quite well in the dense shade of forest canopies, such as oak canopies in Wisconsin, and mixed deciduous canopies of New Jersey and New York where it can form dense thickets that prevent the growth of native plant species.
The analysis of diurnal course of in situ Λ proved the validity of constant-Λ hypothesis over pure, uniform, homogeneous crop canopies but showed irregular and wave-like patterns over heterogeneous, mixed crop canopies.
