Figure Captions
Figure 1 . Potential changes in ɑ and β-diversity of soil
organisms resulting from the cessation of grazing. ɑ-diversity can
potentially increase or decrease independently of changes in
β-diversity, which can also increase or decrease, from a starting
position (indicated in red).
Figure 2. Locations of the 12 sites. Numbers correspond to the
different sites: 1) Glen Saugh; 2) Ben Lawers; 3) Glen Finglas; 4) Glen
Shee; 5) Lake District; 6) Moor House; 7) North Pennines; 8) Yorkshire
Dales; 9) Peak District; 10) Snowdonia; 11) Exmoor; 12) Dartmoor.
Background map depicts soil organic matter concentrations (Joneset al, 2016): darker colors indicate high carbon stocks. Picture
of Glen Shee (inset) shows a typical pattern as a result of grazing:
higher grass cover at the grazed side of the fence with dominance ofNardus stricta and dominance of ericaceous shrubs, such asCalluna vulgaris on the side of the fence where grazers were
excluded. Photo: M. Schrama.
Figure 3. Response ratios of different species groups to
cessation of grazing (±SD). Light brown bars indicate soil microbes,
dark brown bars indicate soil fauna, green bars indicate plants. A)
Effects on ɑ-diversity (species richness); B) Effects on β-diversity
(homogenization). Positive values indicate an increase in diversity as a
result of grazer removal and a negative value indicates a decrease in
diversity. Stars indicate significant differences: *** p<
0.001; ** 0.001 < p < 0.01; *0.01 < P
< 0.05; ns: not significant
Figure 4. Response ratios of ɑ diversity (±SD) of relatively
rare, common and widespread microbes, plant species and soil fauna to
abandonment. Light brown bars indicate soil microbes, dark brown bars
indicate soil fauna, green bars indicate plants. A positive value
indicates an increase in species richness in response to removal of
grazing; a negative value indicates a decrease in species richness as a
result of abandonment. Stars indicate significant differences: ***
p< 0.001; ** 0.001 < p < 0.01; *0.01
< P < 0.05; ns: not significant.
Figure 5 . Long term effects of cessation of grazing on local
(ɑ) and compositional (β) diversity. For all groups except mites,
collembolans and bacteria we found a significant decrease in species
richness when grazers were excluded. There was a more varied response
for β-diversity: some groups, such as nematodes, exhibited a strong
community divergence, indicating that grazing removal results in
increased β-diversity. Other groups, such as, fungi and protozoa
exhibited a community convergence, indicating that cessation of grazing
led to a decreased β-diversity, while the β-diversity of bacteria was
not affected.