3D-imaging technologies provide measurements of terrestrial and aquatic ecosystems'
structure, key for biodiversity studies. However, the practical use of these observations
globally faces practical challenges. First, available 3D data are geographically biased,
with significant gaps in the tropics. Second, no data source provides, by itself,
global coverage at a suitable temporal recurrence. Thus, global monitoring initiatives,
such as assessment of essential biodiversity variables (EBVs), will necessarily have
to involve the combination of disparate data sets. We propose a standardized framework
of ecosystem morphological traits - height, cover, and structural complexity - that
could enable monitoring of globally consistent EBVs at regional scales, by flexibly
integrating different information sources - satellites, aircrafts, drones, or ground
data - allowing global biodiversity targets relating to ecosystem structure to be
monitored and regularly reported.