New seafloor in situ laboratories based on fixed and mobile robotic platforms to monitor indicators of deep-sea ecosystem functioning and address their vulnerability to industrial activities and climate change

Abstract

In the recent decades, the development of fixed observatories has shed light on short-term environmental variability at the ocean floor, in relation to resource pulses or hydrodynamic forcing. Any ecological impact assessment in the deep-sea, in the context of industrial activities or climate change, should address potential synergies among stressors accounting for such natural climate-sensitive instabilities.In this context, however, our capacity to monitor functional responses of ecosystems at great depth is still critical. Opportunities raised by newly available sensing technologies enable to downscale these observations and fill gaps in our understanding of how the environmental dynamics interplay with key ecosystem functions. Here, we present the result of pilot experiments in different deep-sea hotspots (e.g. submarine canyons, cold seeps or hydrothermal vents) showing how cost-effective modular macro and micro-observing platforms enable to document the interaction of fauna with transient biogeochemical processes in their habitat. Moreover, we show how fluid and adaptive networks of fixed and mobile robotic platforms can be used to expand our monitoring capability over larger and complex geomorphologies, providing at the same time those tools required for direct manipulation capability in perturbations experiments (e.g. simulating maritime industrial activities in terms of photic contamination, noise, and sediment resuspension). Such in situ microscale observations are to be developed in any habitat targeted for protection and conservation (e.g. MPA, VME, or areas considered for EIA) especially where down-welling and upwelling phenomena, massive organic inputs, geophysical instabilities such as volcanic eruptions as well as industrial impacts, act as key factors driving the dynamics of deep-sea communities and the functions they hold