Data from: Long-term impacts of changed grazing regimes on the vegetation of heterogeneous upland grasslands

Marginal agricultural land, which in the UK refers particularly to upland
grazings, will see changes in management driven by markets, subsidies,
grants and environmental change with implications for biodiversity. Using
a large-scale, long-term grazing experiment in the UK uplands we assessed
the impact of intensification (tripling sheep numbers), abandonment
(removal of sheep) and grazer diversification (partial replacement of
sheep by cattle) on vegetation composition in a heterogenous area of
grassland. Species benefiting from increased grazing included Anthoxanthum
odoratum, Nardus stricta, and Trichophorum cespitosum. Species that
benefitted from the removal of grazing included Narthecium ossifragum,
Pteridium aquilinum, and Vaccinium myrtillus. Responses differed between
vegetation communities; the more productive acid grassland communities
showed little change when grazing was removed, whilst the less productive
mire communities contained species, capable of increasing after grazing
removal. Increased grazing and, to a lesser extent, the introduction of
cattle increased species diversity. Synthesis and applications: Vegetation
change in relatively infertile grasslands is slow and features shuffling
dominance amongst species in the initial vegetation. Initial structural
changes affect other trophic levels in this experiment; the slow change in
composition will affect the system over longer timescales. Management
decisions in the uplands encompass complex trade-offs between production,
biodiversity and a range of ecosystem services. Predicting the
consequences of decisions is difficult given the slow dynamics of
unproductive habitats.