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NRRSS National Riverine Restoration Science Synthesis. What is Restoration?. The goals, objectives, targets and endpoints of restoration can be difficult to define. The following slides give a brief introduction to this complex topic. NRRSS National Riverine Restoration Science Synthesis.
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NRRSS National Riverine Restoration Science Synthesis What is Restoration? The goals, objectives, targets and endpoints of restoration can be difficult to define. The following slides give a brief introduction to this complex topic
NRRSS National Riverine Restoration Science Synthesis Restoration Trajectories Restoration is: “returning a system to a close approximation of its condition prior to disturbance, with both the structure and function of the system recreated”. (National Research Council 1992)
NRRSS National Riverine Restoration Science Synthesis Restoration vsRehabilitation • As the prior graph illustrates, it is important to distinguish restoration (in the direction of the pre-existing, undamaged state) from rehabilitation (seeks only to improve conditions) • Targets are necessary to distinguish restoration from rehabilitation • Indicators are needed to measure progress • Goals may be much broader than specific targets, and might include social goals such as stakeholder involvement
NRRSS National Riverine Restoration Science Synthesis Restoration Definitions • Lake (2001) provides an excellent review of restoration definitions. One common definition is: • “The process of inducing and assisting abiotic and biotic components of an environment to recover to the state that they existed in the unimpaired or original state” (Bradshaw 1997) • However, • in many cases knowledge of such a state is not available and return to that state is not possible • restoration may be carried out passively (degrading forces are abated) or actively (also driven by intervention)
NRRSS National Riverine Restoration Science Synthesis More RestorationDefinitions • An intentional activity that initiates or accelerates the recovery of an ecosystem with respect to its health, integrity and sustainability • the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed • attempts to return an ecosystem to its historic trajectory (but perhaps not to its former state) • established from historical, reference, comparable ecosystems and other information (Society of Ecological Restoration 2002)
NRRSS National Riverine Restoration Science Synthesis Goals &Targets • clear and achievable goals are essential • goals or targets may be set by reference areas, historical data, or compilation from many fragments of an idealized scenario • this language emphasizes historical condition (and is to some extent contradicted by the following) • should be forward-looking • desired characteristics of system of future, not what existed in the past (“sensible goals”) • should consider a range of options • implies societal evaluation of alternatives (Hobbs and Harris 2001)
NRRSS National Riverine Restoration Science Synthesis Goals (some pragmatic considerations) • Will need to be determined iteratively by matching restoration potential against societal desires • as much process (considering perspectives of stakeholders) as product-oriented (adaptive) • need to be economically possible and achievable • will be basis for recognizing success • success will depend on process of arriving at mutually-agreed upon goals (Hobbs and Harris 2001)
NRRSS National Riverine Restoration Science Synthesis The Iterative Process
NRRSS National Riverine Restoration Science Synthesis Goals, Objectives& Performance • Goals are ideals • Objectives are concrete measures taken to achieve goals • Performance standards (aka design criteria and success criteria) are used to evaluate whether objectives are met • The more explicit the objective, the easier it is to determine if objectives (and thus goals) are met • eg, plant riparian vegetation at 20 stems/m2 (Society of Ecological Restoration 2002)
NRRSS National Riverine Restoration Science Synthesis Reference Sites • May be critical to setting goals • Might this better be termed, “sources of knowledge about the natural state”? • ie, does an emphasis on reference sites conjure up images of past, pristine, equilibrium, etc? • Sources of knowledge about the natural state • natural analogue (aka reference site) • historical reconstruction • best professional judgement • desired future state (Society of Ecological Restoration 2002)
NRRSS National Riverine Restoration Science Synthesis Appropriate Restoration Endpoints From a community ecology perspective, an appropriate restoration endpoint might be based on any of the following: • structural (species richness, focal groups) • functional (processes, eg production) • biodiversity and ecosystem function linkage • keystone species • natural disturbance regime • enhancement of succession and dispersal to reach endpoint sooner • initial conditions (Palmer et al. 1997)
NRRSS National Riverine Restoration Science Synthesis Ecological Restoration Glossary • Restoration: to bring back into a former or original state. • Rehabilitation: any restoration of elements of structure or function (aka “repair”) • Reclamation: rehabilitation of severely degraded sites • Re-creation: reconstruction of a system that is so severely disturbed that nothing is left to restore • Ecological recovery: leaving a system alone, to recover on its own