Man and the Last Great Wilderness: Human Impact on the Deep Sea

Abstract

The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life – SYNDEEP workshop (September 2008). A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past) to exploitation (present). We predict that from now and into the future, increases in atmospheric CO2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this review with a short discussion on protection and management methods.

The Benthic Megafaunal Assemblages of the CCZ (Eastern Pacific) and an Approach to their Management in the Face of Threatened Anthropogenic Impacts

“…The faunal assemblages encompass true abyssal species, notable among them Isopoda, Nematoda and Foraminifera and Echinodermata. These conclusions have also been confirmed by more recent studies (Ramirez-Llodra et al, 2011).…”

Twenty thousand sterling under the sea: Estimating the value of protecting deep-sea biodiversity

“…To be able to value these changes, it is crucial to understand the threats to the marine ecosystem and their effects on biodiversity. Scientists agree that despite its remoteness, the deep-sea is far from being unaffected by human activity and wide-spread changes are already noticeable today (Benn et al, 2010;Fosså et al, 2002;Ramirez-Llodra et al, 2011;Van den Hove et al, 2007). Climate change, which is resulting in increasing ocean surface temperatures and ocean acidification, is thought to be the biggest future challenge for the deep-sea ecosystem (Ramirez-Llodra et al, 2011).…”

Economic Valuation of Marine and Coastal Ecosystems: Is it currently fit for purpose?

“…It accounts for nearly 91% of the world's ocean surface, but is being affected by anthropogenic impacts such as increasing acidification and rising temperatures, pollution, exploitation of fish, and extraction of minerals and hydrocarbon resources (Benn et al, 2010;Ramirez-Llodra et al, 2011). To date, scientists still know relatively little about the deep sea and "safe limits" for resource exploitation are either unknown or very uncertain.…”