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

2002), in addition to their dual purposes of fiber production and economic gain.
Under these circumstances it is perhaps justified. In temperate Europe, alien
woody species are unfortunately still used, especially in the technical reclamation
of derelict sites. The species used might even include ones recognized
as highly invasive, e.g., Acer negundo, Quercus rubra, Robinia pseudoacacia,
and Pinus strobus. We strongly discourage the use of such aliens in restoration
programs because of their possible uncontrolled subsequent spread. Moreover,
alien woody species can usually be replaced by native taxa providing comparable
economic profit.
6.6 Implementation of Scientific Knowledge into Restoration Plans
The major task for scientists engaged in restoration programs is to advise on the
biotic/abiotic state of the ecosystem (the boundary conditions of restoration)
and to suggest pathways that are likely to occur on a restored site whether it has
been exposed to unassisted succession or active manipulation. Restoration ecologists
should be able to specify the most suitable target communities (Perrow
and Davy 2002) from a possibly extensive list of options and compare their predictions
with reality through monitoring. To achieve a successful prediction,
information from three sources can be exploited: (i) detailed quantitative case
studies; (ii) comparative studies over a larger geographical range and across
environmental gradients; and (iii) qualitative and site specific knowledge based
on local information (Prach et al. 2001). The best scenario is obviously where
results are available from a detailed case study from a site under restoration,
or if there is time and resources, to schedule and carry out a pilot study. This
situation is not common and the pilot study is not always carried out in the same
conditions of soil type and intensity of disturbance. Therefore, predictions are
often based on less precise information.
Emphasis is often placed on the low predictability and high stochasticity of
succession, especially at the species level (Pickett et al. 2001, Fukami et al.
2005). We are less skeptical and consider both unassisted and manipulated successional
trajectories to be predictable to a certain degree required for projected
restoration schemes. The level may only represent growth forms or functional
species groups rather than a detailed species sequence. Report cards based on
indicators of abiotic and species changes can also be used to guide restoration
(Walker and Reuter 1996).
Various Expert Systems or Decision-Support-Systems can be developed to
transfer the knowledge of succession and its manipulation into restoration programs;
unfortunately, few have been published or used (Hill 1990, Hunt et al.
1991, Prach et al. 1999, Hill et al. 2005). Such systems should be easy to use and
provide straightforward, robust answers to simple questions (Luken 1990). For
practical use, they are more efficient than mathematical models because they
are based on a wider variety of information and not only on quantitative data
and mathematically derived functions. Vague, intuitive knowledge and precise
quantitative information can be successfully combined (Noble 1987). Using this
approach, the expert system SUCCESS predicts the sequence of spontaneous
seral stages and dominant species change in various human-disturbed habitats
in central Europe (Prach et al. 1999). The system has a potential to be extended
and include predictions of the manipulation of succession.
Chapter 6 Manipulation of Succession 139