Plant diversity and botanical composition in an Atlantic heather-gorse dominated understory after horse grazing suspension: Comparison of a continuous and rotational management

摘要: Abstract Floristic diversity changes substantially depending on the type of land management. We evaluated impact a continuous (CG) and rotational (RG) grazing system dynamics plant community composition in heather-gorse understory after two six-year pause from horse grazing. Previously grazed sites had higher total rare species richness than ungrazed (UN), regardless system. The positive previous was CG continued six years both systems. Seven high conservation interest heathlands were present studied areas. Most them associated to management none exclusively RG. reduction shrub component by led decrease gorse dominance, thus potentially reducing fire risk increasing diversity. extent effect controlling excessive accumulation combustible material favoring differed when relative abundance species, not solely number taken into account (Simpson’s dominance increased Pielou’s evenness decreased years). Overall, effects an Atlantic dominated still apparent 2 or 6 interruption, although declined interlude. Rotational revealed slight advantage upon control biomass long term, assisted maintain more evenly over time. alpha beta indices confirmed that similarity between years.