Toward More Integrated Ecosystem Research in Aquatic and Terrestrial Environments

Aquatic and terrestrial ecosystems are tightly linked through the fluxes of organisms and matter. However, aquatic and terrestrial ecologists have mainly studied these ecosystems separately, a "splendid isolation" historically fostered by disciplinary boundaries between institutes and funding schemes. Here, we synthesize the progress made in joint aquatic and terrestrial research and suggest new approaches to meeting future research challenges in changing environments. Aquatic and terrestrial organisms use cross-system subsidies to a comparable extent and addressing reciprocal subsidies is therefore necessary in order to understand biodiversity and functioning of both aquatic and terrestrial ecosystems. We suggest that the metaecosystem framework could be expanded to explicitly consider cross-system fluxes of matter differing in magnitude and quality. We further advocate the inclusion of cross-system analyses at broader spatial extents, for which remote-sensing applications would be a useful tool in environmental research at the land-water interface. A cross-ecosystem approach would therefore be valuable for a more thorough understanding of ecosystem responses to various stressors in the face of rapid environmental change.