Canopy structure and understorey light availability in <i>Nothofagus</i> and podocarp-broadleaf stands in a New Zealand forest

The ability of some ectomycorrhizal fungi to access organic sources nitrogen is known influence decomposition, mineralisation and soil carbon storage. consequences for aboveground ecosystem structure processes are less well-documented. We used the LAI-2200C Plant Canopy Analyzer compare leaf area index understorey light availability Nothofagus stands arbuscular mycorrhizal podocarp-broadleaf growing on similar soils at a dry forest site in Wairarapa district New Zealand’s North Island. N. solandri was sole overstorey tree three stands, ericaceous shrub Leucopogon fasciculatus prominent understorey. were more diverse varied, major contributors basal being Elaeocarpus dentatus, Hedycarya arborea, Cyathea dealbata, Carpodetus serratus Dacrydium cupressinum. Leaf averaged one unit lower (4.04) than that neighbouring (5.11). Average under (3.6–4.9%) twice beneath (1.6–2.1%). index, greater transmittance, monodominance probably reflects suppression species by short-circuiting cycle. This study expands evidence positive feedback mechanisms stabilising dominance forests.