Recent technological advances make satellites increasingly suited to
grassland monitoring, even across the relatively small and fragmented
natural and semi-natural grasslands in Europe. Additionally, instruments
can be mounted on aircraft to provide multispectral (typically up to a
dozen discrete spectral bands) or hyperspectral (100s or
of under a meter. Furthermore, developments in Uncrewed Aerial Vehicle
(UAV) technology now allows similar data to be captured at spatial
resolutions down to millimetres.
The tools and monitoring techniques across multiple spatial and spectral
scales have developed rapidly in recent years, requiring timely reviews
of the current state of research. This will ensure that land managers
and researchers are kept appraised of the tools and techniques available
to preserve current (semi-)natural grasslands, protect biodiversity and
ensure the continuation of important ecosystem services. To this end, we
aim to provide an overview of the recent progress in the remote sensing
of grassland plant biodiversity, and six functional traits – three
commonly measured (Leaf Area Index (LAI), Nitrogen (N) and Crude Protein
(CP)) and three seldom measured (Leaf Dry Matter (LDM), Potassium (K)
and Phosphorous (P)).