  The challenges presented by climate change are escalating and pose
significant threats to global biodiversity, which in turn increases the risk of
species extinctions. Therefore, meticulous monitoring efforts are necessary to
mitigate the consequential impacts on both human well-being and environmental
equilibrium. Biodiversity mapping is pivotal for establishing conservation
priorities, often accomplished by assessing alpha, beta, and gamma diversity
levels. Two main data sources, in situ and remote sensing (RS) data, are key
for this task. In situ methods entail direct data collection from specific
study areas, offering detailed insights into ecological patterns, albeit
limited by resource constraints. Conversely, RS provides a broader
observational platform, albeit at lower spatial resolution than in situ
approaches. RS-derived diversity metrics have potential, particularly in
linking spectral and biological diversity through high-resolution imagery for
precise differentiation at fine scales. Coupling in situ and RS data
underscores their complementary nature, contingent upon various factors
including study scale and logistical considerations. In situ methods excel in
precision, while RS offers efficiency and broader coverage. Despite prior
investigations predominantly relying on limited datasets, our study endeavors
to employ both in situ and RS data to assess plant and spectral species
diversity across France at a high spatial resolution, integrating diverse
metrics to unravel different biogeographical structures while gaining in
understanding the relationship between plant and spectral diversity within and
across bioregions.
