TDOT 3 GREENTDOT 3 NIR
Use in environmental survey of river channels
This is an example of simultaneous visualization of the shape of a braided rivers and the three-dimensional shape of a riparian forest by surveying from an altitude of 50 meters above ground level. In this watershed, topographic changes due to flooding and changes in riparian forest species covering the floodplain due to sediment inflow to the floodplain have been reported, but the relationship with the topography, including the riverbed, has not been considered. Drone-green laser surveying is expected to reveal the relationship between vegetation and changes in channel morphology due to sediment flow, river discharge, riverbed gradient, and sediment grain size.
Up to four types of reflected pulses can be distinguished with a single irradiation of laser beam.
The first pulse is what is first reflected by the tree, the last pulse is what is reflected at the ground surface, and the middle pulse is what is reflected in the middle of the tree.
It is possible to accurately reproduce the height and shape of trees at the same time as the ground surface.
Developing altitude tint map created from 3D laser point cloud including river channel and topographic shading map after removing vegetation. It allows imaging processes that can easily understand the channel characteristics of a braided river from a 3D fluvial topographic model.
Original data
Topographic shading map
Altitude tint map
Altitude tint map
Cross-sectional view
Bird’s-eye view