The structure of forest canopies is highly heterogeneous at multiple scales. Leaves, twigs, and stems are not organized uniformly in space. For example, some plants have highly clustered leaves (e.g., conifers) while others are less clustered (e.g., Kira et al. 1969). Forest canopies contain gaps, but the size and distribution of these gaps is highly variable and forest/disturbance-dependent (e.g., Yavitt et al. 1995; Asner et al. 2004). Leaf area and woody biomass are not evenly distributed along the vertical axis, with some forests having a larger proportion of the leaf area closer to the forest floor, whilst other forests have most of their foliage near the top (e.g., Parker et al. 2004b). How these elements are organized and connected in space can have profound influences on ecosystem process such as hydrological and biogeochemical fluxes.
- Physical Geography,
Available at: http://works.bepress.com/john_vanstan/14/