LiDAR coverage would have high potential to meet your needs. But the dense and multiple layering in tropical forests may be too much to separate. Lidar analysis is able to separate the vegetation laser hits by elevation to get a sense if hitting dominant vegetation in canopy, or lesser vegetation closer to ground. In less dense forests, high resolution aerial photos can differentiate individual dominant and codominant trees, especially noticeable in pine hardwood mix. Unfortunately, I don't think I have any examples to share. I am uncertain as to degree that software can recognize individual plants or trees and separate them for density estimates.
But LiDAR coverage is costly affairs as well as availability of the images in the particular period is again a questionable? Beside LiDAR any other imagery might works, If any?