Averting tipping points: Role of restoration management

Abstract

Ecosystem resilience is a fertile topic for research, but there are two senses in which the concept is being examined. When restoration ecologists refer to ‘resilience’, they are usually referring to capacities of species to recover from natural disturbances (developed through adaptation to perturbation regimes over evolutionary timescales; Westman 1978; Dell et al. 1986). This ‘biological’ resilience is conferred to higher levels (communities and ecosystems) by dint of the fact that assemblages of species are often subject to similar landscape-scale disturbances. Restorationists can trigger residual resilience on damaged sites by measured manipulations – skills referred to in Robin Buchanan's guest editorial on vocational training for restorationists in this issue. Such skills are essential to successful restoration at site level, as illustrated in the feature article of Anderson et al. (this issue) on the Puckapunyal Restoration Programme – a program that has achieved extensive recovery of indigenous plant and animal communities after control of pest species, fencing and supplementary revegetation. When researchers working in the transdisciplinary field of ecology and society refer to resilience theory, however, they are often referring to the field of research that focuses on recovery and degradation processes at much larger ‘systems’ scales, particularly where ecosystems and society are linked (Holling 1973; Walker et al. 2006– and see book reviews in this issue). As problems at these scales are harder to detect, researchers need to anticipate trajectories of degradation that can be turned around (or responded to by social transformation) before it is too late (see topics of all three comment pieces in this issue and the research report by Baldwin et al. and Mendham et al. also in this issue). Both ecological and transdisciplinary approaches are equally important, and are cross-fertilizing each other. Restoration ecologists are familiar with state and transition models and acknowledge thresholds of reversibility, points beyond which autogenic recovery will not occur and where a system can precipitously change to something quite different (Holling 1973). But combining these concepts with bigger-picture social–ecological analysis is novel and potentially powerful for the restoration and management of ecosystems. As pointed out by Sam Lake (see interview in this issue) and demonstrated by Anderson et al., big-picture effects cannot be achieved without multiple-site-level projects, but site-level projects need strategic coordination to be effective due to their dependence on and exposure to larger-scale processes in social–ecological systems. It is important that these ideas of thresholds of ‘irreversibility’ are used more and more by researchers and managers in all disciplines, but it is particularly important that these empowering ways of seeing ecosystem change are taken on board by planners and decision-makers. Many planners and policy-makers are working very hard to reduce future damage, but it will not be possible to maintain the health of our systems by simply reducing tomorrow's ‘rights’ to pollute or harvest. Such actions are an indispensable and worthy start, but if a dangerous trajectory is already in train (such as with salinization and greenhouse pollution), alleviation of the problems will not occur after the reduction of future causal factors alone. Interventions to compensate for existing damage – restorative industries – are also needed. In this context, it might be useful to point out that the restoration associated with ‘no net loss’ policies in land clearing (referred to in Gibbons & Lindenmeyer's thought-provoking comment piece, this issue) should not be confused with restoration for compensating existing problems at big-picture level. ‘No net loss’, by definition, is about maintaining a current or future status quo, not addressing past losses. It is very important therefore that ‘bigger-picture restoration’ arguments are not invoked to support the adoption of land-clearing trade-offs referred to as ‘offsets’. Indeed, big-picture arguments could be more logically invoked to define clearing of any bushland technically capable of restoration as a ‘loss’ (and restoration of any other bushland as simply ‘compensation for past losses’) rather than as a ‘gain’. Pragmatism can be useful in times of sudden change and when there is really no other alternative. But as pragmatism is fundamentally about avoiding conflict by slicing the cake ever smaller, its application as a general rule is simply ‘more of the same’. ‘More of the same’ will perpetuate rather than solve our environmental problems (Walker et al. 2006). A more thoughtful and radical shift of mindsets and mechanisms of business is needed, empowered by collective recognition of the large scale of our problems and their potential for sudden collapses. This needs to be a shift not only to ‘resilience thinking’ but also to ‘restoration thinking’ at a very large scale; value adding with creative endeavour – or we may be running the risk of ecological sustainability becoming a mere fantasy.