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

Chapter 7 Restoration as a Process of Assembly and Succession Mediated by Disturbance 163
forces that contributes to alterations in disturbance regime, e.g., change in
fire frequency due to variations in weather conditions, or increased flooding
intensity due to altered precipitation patterns. Such disturbances can then
remove the inertia present in existing ecosystems, resulting in a relatively
sudden response (or adjustment) to novel conditions.
10. Underlying processes. Successional pathways can be irreversibly altered in
terms of composition and velocity when modified by disturbance regimes,
and exposed to gradually or suddenly varying environmental conditions.
Thus, another crucial challenge in restoration ecology is to assess whether
restoration efforts within an ecosystem, such as manipulation of the disturbance
regime, interact with underlying continuous processes. A crucial
insight here is that both external triggering factors and internal variables
may be slow or fast, can occur independently from each other, and can be
disjointed over temporal and spatial scales (Trudgill 1977). Our challenge
is to assess whether management action and underlying processes are in
synchrony and harmony, or whether counter-effects will occur.
The ability to address successfully issues such as those listed above will require
the use and integration of all available conceptual and practical tools. In
this chapter, we have attempted to integrate the concepts from classical successional
approaches and emerging approaches of community assembly. A key
ingredient in doing this is the recognition of the importance of disturbance
and alternative pathways and stable states in ecosystem dynamics. The overall
goal of restoration can be viewed as the modification of ecosystem dynamics
so that the system moves toward some stated target condition. In order to do
this, we need to recognize that the dynamics can be deterministic, stochastic,
or switching between alternative states; the challenge is to identify which type
of dynamic is in play and to then decide what to do about it. The tools to
do something about it will include manipulating the processes of community
assembly (determining what gets there) and succession (what happens subsequently),
and doing so by managing and using disturbance of various types.
We suggest that the improved understanding of dynamics resulting from the
integration of succession, assembly, and disturbance concepts can lead to the
development of more realistic restoration goals and more effective restoration
practice.
Acknowledgments: We thank Joe Walker, Lawrence Walker, and several anonymous
referees for valuable comments on the draft manuscript. We also thank
Peter White for earlier discussions on the role of disturbance in community
assembly.
References
Aronson, J., and Vallejo, R. 2006. Challenges for the practice of ecological restoration.
In: Restoration Ecology: The New Frontier. J. van Andel and J. Aronson (eds.). Oxford:
Blackwell, pp.234–247.
Beierkuhnlein, C., and Jentsch, A. 2005. Ecological importance of species diversity. A
review on the ecological implications of species diversity in plant communities. In:
Plant Diversity and Evolution: Genotypic and Phenotypic Variation in Higher Plants.
B. R. Henry, (ed.). Wallingford: CAB International, pp. 249–285.