Are lakemounts hotspots of productivity and biodiversity?

Abstract

Oceanic seamounts are hotspots of biodiversity, productivity, and other ecosystem processes. Different hydrodynamic processes leading to physical-biological coupling dynamics occur in these systems making them oases in the open ocean. Due to their disproportional effects on ecosystem function (e.g., high biogeochemical rates), seamounts can also be considered ecosystem control points. On a smaller scale, abrupt offshore reefs in large lake ecosystems (i.e., “lakemounts”) may serve similar roles as seamounts by parallel mechanisms. However, very little is known about lakemounts or the physical-biological coupling that could make these isolated habitats an important source of energy production and biodiversity for offshore, open-water regions of large lakes. We hypothesize that lakemount-induced upwellings serve a similarly important process in lakes as seamounts in the ocean, boosting productivity and biodiversity in offshore areas of large lakes. Identification of these biodiversity hotspots and ecosystem control points, and the mechanisms driving their processes, is vital for understanding how climate change may alter physical-biological coupling and resultant community- and ecosystem-level processes. Such linkages may play a key role for effective and cost-efficient environmental conservation and the maintenance of ecosystem function and services in large lake ecosystems in the face of global change.