Native forests and grasslands across the world face a range of threats, including climate change, urbanization, and exotic species invasions. Ecosystem restoration is frequently offered as a partial solution to these threats, because less stressed ecosystems seem better equipped to resist invasion.
“By aiming to restore ecosystem resilience, plant communities can endure in the face of drastic disturbance — whether induced by climate change or biotic invasion,” says Qinfeng Guo, a U.S. Forest Service research ecologist and author, along with co-author Steve Norman, of a chapter in the new book Invasive Plant Ecology. Published by CRC press, the book is intended for students, professionals, and policymakers.
“Resilient ecosystems come back even after severe disturbances, but ecosystems that are not resilient will slowly drift or suddenly shift away from whats desired or expected,” explains Norman. Managing for resilience means focusing on the traits and species including fungi, soil microbes, and animals that let ecosystems resist change and recover after disturbances. A common strategy to boost resilience is making sure that native plants fill all of an ecosystems niches. In highly disturbed areas, this is often accomplished by replanting natives, although exact guidelines as far as the number and type of species that should be planted have not been developed. An urgent future need is to identify native species that will be able to resist invasion by exotic species while adapting to future climate changes.
Climate change and exotic species invasions are usually discussed separately, but as drivers of ecological change they can amplify each other’s effects. For example, a warming climate may cause species in general to migrate to higher latitudes and altitudes. Since exotic invasive plants are usually aggressive colonizers and able to spread quickly, they could slow down or even thwart successful migration of native plants. In this scenario, climate change and exotic invasive species are connected, and restoration efforts that reduce stress from one could also alleviate stress caused by the other.
“The restoration concept needs to evolve past its historical usage, and shift towards maintaining and enhancing ecosystem resilience under novel conditions,”says Guo. Traditional restoration often means taking a degraded area back in time towards presumed historical conditions, or imitating plant communities found nearby. While restoration will always invoke the past, many natural areas have been altered so severely that restoration to a historical condition may be difficult or impossible.
“Historically based restoration will likely work for some species in some places, but not for all,” explains Norman. We hope that we can retain native species and we can do this best by accommodating their individual needs in a changing world.”
For more information contact Qinfeng Guo at firstname.lastname@example.org or (828) 257-4246