It is clear that the environment today is undergoing major changes. Not only rising average temperatures and changing rainfall patterns worldwide, among other things, the increase in the deposition of atmospheric pollutants and changes in land use and management have impacts on global biodiversity. Also forests are not spared from the impact of this global change 'factors (GC-factors). Most of the plant diversity in forests of temperate regions is in the herb layer. Research on the effects of individual GC factors herb layer types are already available, but there is little knowledge available about the interactions between GC factors that can lead to non-linear responses and state changes are not predictable based on the analysis of the GC effects of individual factors. Such responses and changes can have a big impact on the composition, structure and functioning of (forest) ecosystems. The FWO Scientific Research FLEUR spans most of the distribution area of ​​the temperate deciduous loofbosbioom in Europe and thus allows to add excellence to combine data (multitemporal) observations along major environmental gradients with local scale experiments. FLEUR thus forms a unique platform for groundbreaking research that will bring new insights into the functioning of forest ecosystems in a changing environment on the basis of (i) a compilation of available data sets on the dynamics of bosplantengemeenschappen over time, and (ii ) conducting observational studies and complex experiments along major environmental gradients (climate, atmospheric deposition, management).