Table S1.

Sensitivity of lidar-observed LAI on the ratio between leaf reflectance and litter reflectance

Model parameters	Wet season	Dry season
rv *	0.39	0.49
rg *	0.34	0.54
rv/rg	1.15	0.91
Lidar-observed LAI	4.55	4.97

For the same waveform, a lower value of the ratio will yield a higher derived LAI (22). Thus, to rule out the possibility of reflectance-driven increases in LAI during the dry season we chose an average ratio of 1.03 and applied it for all cases. Note that the derivation of LAI from the lidar model is only sensitive to the ratio of the reflectances, and not the reflectances themselves.

^*The reflectance values are adopted from field measurements reported in a previous study (12), and LAI values are produced for the same lidar waveform. Because seasonal changes of r_v and r_g are in the same direction, their ratio has only small variation.