Linking Restoration and Ecological Succession (Springer ... - Inecol

134 Karel Prach et al.
Table 6.2 Situations where heath communities have been restored.
Situation Problems
Raw mineral
wastes
Agricultural
land
Succession
reversal
Lack of seeds and
nutrients
Lack of seeds, growth
of ruderal species,
pH too high
Expansion of
late-successional
species e.g., Betula
spp., Pinus
sylvestris,
Rhododendron
ponticum, Pteridium
aquilinum,
Deschampsia
flexuosa, Molinia
caerulea
Is unassisted
succession
possible?
Yes—but takes a
long time (25
years)
No, soil
conditions
often changed
during
agriculture
No, except
insofar as
heathland
may exist in a
temporary
stage if the
latesuccessional
stage is
damaged
Restoration methods
(in approximate order
used) Selected references
1. Regrade site, add organic
amendments if possible
2. Add seed
3. Add fertilizerr
4. Use nurse crops
5. Transplants—plants
or turfs
6. Grazing control
1. Acidify soils
2. Reduce fertility,
(e.g., by sod cutting)
3. Grazing control
4. Add seeds
1. Reduce fertility
2. Control late-successional
species: mechanical or
herbicidal methods
3. Create conditions for
heathland species to
germinate
4. Add seeds
5. Grazing control
Roberts et al. (1981),
Anonymous (1988)
Pywell et al (1994,
1997), Davy et al.
(1998), Dunsford
et al. (1998), Owen
and Marrs (2000a,b)
Marrs (1988),
Milligan et al.
(2004)
6.4.2.2 Heathlands
Restoration of heathland communities has been described in a number of situations,
from establishment on raw mineral wastes (primary succession), from
abandoned arable land (secondary succession), and where succession has occurred
through inappropriate management of existing heathlands (Table 6.2).
For heathlands, unassisted succession is a serious possibility for restoration of
raw substrates (e.g., sand and mining wastes) where there is sufficient seed rain
from surrounding areas (Roberts et al. 1981). On sand wastes, succession was
slow (ca. 40–60 years for a heathland to develop) and highly variable (Roberts
et al. 1981). Technical solutions can accelerate this process and provide a greater
vegetation cover.
In raw wastes and agricultural land, seeds of heathland species (usually
Calluna vulgaris) are scarce and may even be absent (Pywell et al. 1997),
whereas in late-successional stands invaded by woodland Calluna, seed banks
can persist for greater than 70 years (Pywell et al. 2002b). Seed limitations
can be overcome by adding seeds, shoots with the attached seed capsules, or
topsoil. Often topsoil use provides a more diverse flora than seeds alone because
the soil contains a greater species diversity (Pywell et al. 1994). It is also
possible to either use transplanted turfs or nursery-grown plants (Webb 2002).
Where topsoil or turfs are used there are implications for the donor site and
cost.