Ecosystem restoration: Recent advances in theory and practice
Debate as to whether restoration is feasible is coupled to long-standing disputes regarding the definition of restoration, whether more-damaged lands are worthy of restoration efforts given limited financial resources, and ongoing conflicts as to whether the novel ecosystem concept is a help or a hindrance to restoration efforts. A willingness to consider restoration options that have promise, yet would have previously been regarded as ‘taboo’ based on the precautionary principle, is increasing. Functional restoration is becoming more prominent in the scientific literature, as evidenced by an increased emphasis on functional traits, as opposed to a simple inventory of vascular plant species. Biodiversity continues to be important, but an increasingly expansive array of provenance options that are less stringent than the traditional ‘local is best’ is now being considered. Increased appreciation for soil health, plant–soil feedbacks, biological crusts, and water quality is evident. In the United States, restoration projects are becoming increasingly motivated by or tied to remediation of major environmental problems or recovery of fauna that are either charismatic, for example, the monarch butterfly, or deliver key ecosystem services, for example, hymenopteran pollinators.