Biogeomorphic Keystone Species

The term biogeomorphic keystone species is drawn from the ecological lexicon keystone species —a species whose impact on its community or ecosystem is extensive and disproportionately large relative to its abundance, such that its presence or absence would lead to wholesale changes in the ecological system. Similarly, biogeomorphic keystone species profoundly impact landscapes, such that their introduction or removal would cause fundamental changes in the earth surface processes and forms; furthermore, their impacts are species‐specific. For example, dams and ponds created by North American beavers ( Castor canadensis ) transform local landscapes and produce unique hydrogeomorphic and ecological effects specific to beavers. Research has identified that American sycamore ( Platanus occidentalis ) plays a role as a biogeomorphic keystone species in bedrock‐controlled fluvial environments by developing pools leading to local scale landform metamorphosis. These biogeomorphic pools are developed by sycamore root‐induced channel‐bed bioweathering—an effect unique to sycamores. Moreover, the biogemorphic keystone roles are context‐dependent comparable to ecological keystone species. For example, American sycamore plays a keystone role when they are established along (i) bank margin or in channel, (ii) on bedrock/shallow soil, and (iii) when they are at the mature stage of their life.