Vegetation survey
Aim: representative stratified random sampling of
- patches of natural /semi-natural vegetation
- patches of arable fields and cultivated grasslands
- linear elements
Number of plots per site (4x4 km): about 150-250 plots
Size of plots: in general 10x10 m = 100 m²; different in linear elements (still 100m², but rectangular)
Abundance is estimated according to Braun-Blanquet
Frequency of surveys: every 3 years