Five decades of ground flora changes in a temperate forest: The good, the bad and the ambiguous in biodiversity terms

We explore how the ground flora of a temperate woodland (Wytham Woods, southern England) changed in terms species-richness, cover and biomass over five decades; what drivers change were; possible future as consequence decline Fraxinus excelsior canopy dominant. Vascular plants were recorded from 164 permanent, 10x10 m plots, distributed 141 grid, 1974, 1991, 1999, 2012, 2018. Species presence frequency/abundance each plot estimated used to model changes. Changes vegetation composition structure analysed. Stands opened out by thinning or which became denser through tree growth gained lost species respectively, particularly non-woodland species. Deer pressure favoured spread Brachypodium sylvaticum reduced Rubus fruticosus. No obvious impacts climate change, eutrophication invasive detected records although other signs suggest these are starting affect flora. Just 12 235 contributed 47% all occurrences, 82% 87% modelled biomass. conclude that is highly variable decadal timescales, but patterns observed differ according measures (species richness, cover, biomass, etc). Site level short-term swamped effects slower acting regional/global drivers. Legacy seen greater richness specialists older woodland. While some can be mitigated management, others largely beyond control at site level.