This volume discusses environmental issues associated with deep-sea mining, with an emphasis on potential impacts, their consequences and the policy perspectives. The book describes the methods and technologies to assess, monitor and mitigate mining impacts on marine environments, and also suggests various approaches for environmental management when conducting deep-sea mining. The volume brings together information and data for researchers, contractors, mining companies, regulators, and NGOs working in the field of deep-sea mining. Section 1 highlights the various environmental issues and discusses methods and approaches that can help in developing environmentally sustainable deep-sea mining. Section 2 details the results and outcomes of studies related to impact assessment of deep-sea mining, and proposes methods for monitoring. Section 3 discusses the need and means for developing data standards and their application to deep-sea mining. Section 4 discusses the policies, approaches, and practices related to deep-sea mining, suggests formats for developing environmental impact statements (EIS) and environmental management plans (EMP), and describes national and international regulations for environmental management. Section 5 concludes the text by putting deep-sea economic activities into an environmental context and conducting techno-economic analyses of deep-sea mining and processing.

This book is a sequel to ’Deep-Sea Mining: Resource Potential, Technical and Environmental Considerations’ (2017) and ‘Environmental Issues of Deep-Sea Mining: Impacts, Consequences and Policy Perspectives’ (2019), and aims to provide a comprehensive volume on different perspectives of deep-sea mining from specialists around the world. The work is timely, as deep-sea minerals continue to enthuse researchers involved in activities such as ascertaining their potential as alternative sources for critical metals for green energy and other industrial applications, as well as technology development for their sustainable exploration and exploitation, while addressing environmental concerns. With a steady increase in the number of contractors having exclusive rights over large tracts of seafloor in the ‘Area’, i.e. area beyond national jurisdictions, the International Seabed Authority, mandated with the responsibility of regulating such activities, is in the process of developing a code for exploitation of deep-sea minerals. These, coupled with growing interest among private entrepreneurs, investment companies and policy makers, underscore the need for updated information to be made available in one place on the subject of deep-sea mining. The book evaluates the potential and sustainability of mining for deep-sea minerals compared to other land-based deposits, the technologies needed for mining and processing of ores, the approach towards environmental monitoring and management, as well as the regulatory frameworks and legal challenges to manage deep-sea mining activities. The book is expected to serve as an important reference for all stakeholders including researchers, contractors, mining companies, regulators and NGOs involved in deep-sea mining.

The 16th Deep-Sea Biology Symposium was held in Brest, France, and online from the 12th to the 17th of September 2021. The first DSBS hybrid symposium brought together scientists, students, managers, policymakers, and industry specialists who presented advances in deep-sea research. Themes of the symposium, and of this Research Topic, include: - Conservation and stewardship: natural/anthropogenic impacts, conservation, governance. This includes but it is not limited to: deep-seabed mining, pollutants and debris, climate change impacts; marine spatial planning; stewardship of the deep ocean; - Biodiversity and ecosystem functioning: biodiversity patterns, species distribution, function; from polar to temperate regions, mesopelagic to hadal, microbes to large pelagic; - Life-history traits and population connectivity: reproductive ecology, larval development and dispersal, and population connectivity; - Adaptations of deep-sea organisms: from molecules to organisms: how life adapts to extreme conditions, including for instance bioluminescence and vision in the deep-sea; - Access to the deep sea: technological and methodological advances to access and investigate deep-sea life, including observatories and cutting edge technologies –e.g. A.I. and omics; - Deep-sea biomimicry: discovery of new technologies inspired by deep-sea biological solutions; - Science communication in the deep including innovative approaches to increase ocean literacy (merging “arts & sciences”).

This comprehensive book contains contributions from specialists who provide a complete status update along with outstanding issues encompassing different topics related to deep-sea mining. Interest in exploration and exploitation of deep-sea minerals is seeing a revival due to diminishing grades and increasing costs of processing of terrestrial minerals as well as availability of several strategic metals in seabed mineral resources; it therefore becomes imperative to take stock of various issues related to deep-sea mining. The authors are experienced scientists and engineers from around the globe developing advanced technologies for mining and metallurgical extraction as well as performing deep sea exploration for several decades. They invite readers to learn about the resource potential of different deep-sea minerals, design considerations and development of mining systems, and the potential environmental impacts of mining in international waters.