incorporating ty's figure

[NidhiVinod]

Ty’s thoughts

• Mean vs. instantaneous light environment (Fig. below).
• Respiration (leaf): suppressed in light, does this effect diminish toward darker microenvironments?
• Photorespiration: How does this change with height (e.g., CO2, temperature)?
• High CO2 in the understory: shifts mechanisms of photosynthetic temperature sensitivity (from VCmax to Jmax).
• Consequences of leaf trait variation with height (and microenvironment) for thermal responses (larger leaves in shade + low wind where boundary layer is less important; leaf thickness mitigates rapid heating in intermittent sun beams)
• *Many of these are ideas that are probably very under-studied. How much are we providing a review, and how much a roadmap for future work? o Tansley guidelines: “[the review should] be less of an exercise in literature documentation and more of a forum for the presentation of ideas”

Figure light fraction: Example of microenvironment varying independently of mean environment across height in BCI. Lidar-derived light fraction is calculated for each voxel. The mean light fraction decreases with depth in the canopy (c), but the spatial variation in light fraction at a given height increases (a). Temporal variation can be expected to be similar to the fine scale spatial variation. As the sun traverses the sky, the beamline intersects a dynamically variable distribution of obstacles, resulting in temporally variable illumination of a given point (e.g., leaf) within the canopy. We could produce a figure like this from NEON data, and could even potentially simulate the sun path to calculate the temporal variability of illumination across depth.

[NidhiVinod]

Elsa's thoughts-- I’ve been thinking along similar lines to what Ty suggested. See below for a figure I created for a recently submitted proposal. We could build off those NEON sites or others for the simulations Ty suggested.