Regardless of dictionary definitions, anyone who has ever restored a car or a house knows that it is not only possible, it is also a rewarding experience that allows one to regain use of something that has been damaged or fallen into disrepair. But no one expects a restored house to be the same house that it was before. The paint may be the same color, but if lead paint was used something less toxic would now be substituted. No one would propose the use of asbestos as insulation or wallpaper known to burst into flames from a mere spark. In some parts of the world, air conditioning might be installed to protect the remaining historic components of a structure from the elements; if threatened by floods, a historic house undergoing restoration might be raised up on pilings. Where a house might have been home to a family of five, it might now be used as an office or retail store.
The same is true of restoring ecosystems. Ecosystems can and are being restored by the thousands all over the world: forests, wetlands, deserts, coastal uplands. Trees are planted, exotic species removed, fire reintroduced, hydrology repaired. Are these restored ecosystems exactly like they were pre-disturbance? Of course not; why would we expect them to be? Neither ecological theory nor the broad practice of restoration (of any kind) would lead us to think that this would be possible, much less desirable. The Society for Ecological Restoration International (SER) has been long concerned with how ecosystems actually work and how restoration goals are chosen. For nearly 20 years, debates have raged among the membership over definitions and targets. But when the dust settles we generally agree that ecosystems are dynamic and that steady states are relatively short-term phenomena. Some would argue for 100% historical fidelity for ecological restoration projects (â€œbring back to an original conditionâ€), but these are in the small minority and this idea implies using living ecosystems as museum collections rather than functional entities â€“ just as a Model T Ford restored with all original materials would likely be displayed and rarely or never used.
Thus, ecological restoration becomes â€œâ€¦the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed.â€ (SER Science & Policy Working Group, 2002 & 2004; see http://www.ser.org/content/ecological_restoration_primer.asp). It is not about reestablishing a mythical steady state, but rather reversing degradation or removing disturbances so as to allow for the reestablishment of â€œirreversible directional changeâ€ or ecosystem trajectory. Deciding â€œrestoration to what?â€ and defining ecological restoration targets is critically important to developing appropriate methods and measuring success or failure. Clearly articulating the goals of restoration is crucial to explaining our work to the public and policy makers and to avoid misinterpretations of intent or ability.
And what about people? First, I agree that humans have modified virtually all ecosystems on the planet. But not all of these influences can be described as negative. Indeed, human beings were first species components of ecosystems and later destroyers of them. Many ecosystems, especially in Africa and Asia, evolved with humans as part of the landscape. Mainly North American ideals of pristine ecosystems, wilderness, and nature fail to recognize the ancient role of humans in the landscape. While acknowledging that we humans have been making ecological mistakes for millennia, it is the current unprecedented loss of biodiversity, reduction of ecosystem services, and global climate change that we should seek to halt and reverse wherever we can. Many would argue that our future as a species depends upon it.
Rejecting ecological restoration in favor of â€œmanagingâ€ all ecosystems is business as usual in a world becoming more degraded every day. Further, management of these ecosystems would not necessarily be driven by science. Management is about control, about status quo, while ecological restoration is explicit about its intent to improve environmental conditions â€“ to restore ecosystem functions, prevent species losses, reintroduce extirpated species, and allow for ecosystem evolution and the accrual of ecosystem services. And in order to achieve successful restoration, it must be based on intensive scientific research. If we conduct restoration in this manner, then there will be little room for semantic confusion.
Incidentally, among the hundreds of thousands of hits, my own search of Google turned up eight hits for â€œecological restoration is impossibleâ€ and just 15 for â€œecological restoration is possible.â€ So clearly the online discussion is not about whether ecological restoration is possible, but rather about how we can best get this critical work done.
Contributed by George D. Gann, Vice Chair, Society for Ecological Restoration International (http://regionalconservation.org/ircs/aboutus/GeorgeGannbio.asp)