Deep-sea ecosystems are facing degradation which could have severe consequences for biodiversity and the livelihoods of coastal populations. Ecosystem restoration as a natural based solution has been regarded as a useful means to recover ecosystems. The study provides a social cost-benefit analysis for a proposed project to restore the Dohrn Canyon cold water corals and the deep-sea ecosystem in the Bay of Naples, Italy. By incorporating ecosystem service benefits and uncertainties related to a complex natural-technological-social system surrounding restoration activities, the study demonstrated how to evaluate large-scale ecosystem restoration activities. The results indicate that an ecosystem restoration project can be economic (in terms of welfare improvement) even if the restoration costs are high. Our study shows the uncertainty associated with restoration success rate significantly affects the probability distribution of the expected net present values. Identifying and controlling the underlying factors to improve the restoration successful rate is thus crucial.

This chapter deploys assemblage theory and thinking to bring together a unique set of insights on the seabed ranging from the ecological, to legal, practice to theoretical. It does so with a particular aim in mind: to integrate debates pertinent to understanding the frontier space of the sea floor. Whilst there are increasing calls for interdisciplinary integration in the marine sciences, combining the natural and social sciences research on the space of the seabed and its potential for mining tends to be siloed with work addressing component parts of such possible processes: ecosystem and ecosystem service aspects, legal dimensions, and geopolitical aspects, to name but a few. Whilst these contributions touch upon intersecting issues (society and environment; law and economics, and so on) they remained centered on particular disciplinary and scientific offerings to understanding the seabed and prospect of seabed mining. This chapter offers a thoroughly ‘joined up’ approach, which presents a prism through which to better understand the issues at stake in venturing to the new vertical frontiers of ocean extraction.