Engaging with novel ecosystems

Novel ecosystems are assemblages of species that have not co-occurred historically; such ecosystems result directly and indirectly from human activities, are relatively stable, and occupy space alongside existing semi-natural or natural ecosystems in the world's landscapes and seascapes. Although recognized for at least three decades, novel ecosystems have heretofore been overlooked and apparently undervalued by both the scientific and conservation communities. As a consequence, they have also been largely ignored in the policy context. Novel ecosystems currently account for around 40% of the ice-free land on Earth, and probably a similar figure in the marine environment, although less work has been undertaken in the world's coastal seas and oceans in this regard. Such ecosystems are a blind spot in global conservation and restoration priorities as well as in discussions of environmental management and sustainable development. This oversight limits our effectiveness in intervening appropriately in ecosystems that are undergoing rapid environmental changes. Novel ecosystems are now critical for the maintenance of biodiversity at the genetic, species, and ecosystem levels, while at the same time providing vital ecosystem services (eg carbon sequestration; fiber; food; water production, protection, and purification; and nutrient cycling). From the viewpoint of cultural ecosystem services, novel ecosystems are frequently the primary places where people connect with nature. Indeed, people around the world cherish secondary forests and woodlands, regulated rivers, constructed wetlands, and invader-dominated marshes, often without realizing how distinct these ecosystems are from their historical counterparts. Many ecologists are justifiably concerned about the implications of engaging with novel ecosystems and, in particular, lament that these ecosystems differ from those that formed the land- and seascapes with which they are familiar. However, inattention to novel ecosystems is no longer a valid option. We need to see these as part of a “futurescape” where new ecosystems mix with the old. Dealing with novel ecosystems emphasizes rather than downgrades the importance of conserving and restoring systems that retain historical continuity. Of course, this imposes challenges, but it can help us anticipate the changes necessary for future sustainable ecosystem management and conservation – in a world where mitigation against, and adaptation to, climate change have become the dominant ecological management paradigms. Without detracting from the need to continue to properly manage relatively less-impacted ecosystems, there is a range of unexploited opportunities available to develop knowledge of, and subsequently manage, novel ecosystems. Indeed, where the biosphere is undergoing irreversible changes, management – and even conservation – of the resulting novel ecosystems is the only viable option. To that end, participants at a recent meeting on Pender Island, British Columbia, Canada, sounded a “Call for Action” (www.restorationinstitute.ca/projects). This Call for Action asserts that appropriate understanding and management of novel ecosystems can help resolve several problems in international-level (especially REDD+ and land-use change issues) as well as national-level programs and funding initiatives dealing with climate change, biodiversity loss, and related policy processes. International biodiversity policy makers must also consider the role that such ecosystems play in delivering ecosystem services as well as in helping the conservation, wise use, and benefit-sharing of biodiversity. Perhaps most importantly, the Call for Action urges that the developing Intergovernmental Platform on Biodiversity and Ecosystem Services and, where relevant, the existing Intergovernmental Panel on Climate Change incorporate the topic of novel ecosystems in their forthcoming work programs on knowledge development and assessment for biodiversity and climate-change science. Furthermore, discussions on ecosystem restoration at the November 2011 meeting of the Convention on Biological Diversity's Subsidiary Body on Science, Technical, and Technological Advice (Montreal, Canada) will offer a tangible opportunity for starting to develop policy on novel ecosystems in the broader context of ecological restoration. Ecologists, educators, managers, and policy makers alike must appreciate that we are living in an increasingly dynamic world, one where restoration of ecosystems to historical baselines will need to join new management strategies that focus on conservation and use of biodiversity and provision of ecosystem services. Indeed, classical management approaches will become increasingly difficult and, in some ecosystems, practically impossible to implement successfully. True, the various stakeholders need much more information about novel ecosystems and the synergistic relation between them and the ecosystems we are more familiar and comfortable with. But achieving the Aichi 2020 Biodiversity Targets, the Millennium Development Goals in 2015, and sustainable development in general will require a better appreciation of the part that novel ecosystems play in providing the biosphere with the services it needs to function, and that we must have in order to survive.

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