Deep sea mining - ecological impacts

The resources of the world's oceans are attracting ever more interest. But how can they be exploited without damaging the environment? The German research vessel "Sonne" is being used to carry out extensive studies related to this issue. 

Treasures on the seabed: Even iron is one of them. © Thinkstock / camij

The demand for raw materials in our technology-based society is growing all the time. For example, rare earths are needed in many key technologies, for example in the production of mobile telephones and semi-conductors. Terrestrial resources are limited, which is why marine deposits are attracting ever more interest.

Cobalt-rich manganese crusts

The types of mineral resources of relevance for deep-sea mining can be found in manganese nodules (polymetallic nodules), cobalt-rich iron and manganese crusts, massive sulphide deposits and ore slurries. The manganese nodules are of economic interest because of their relatively high copper, nickel and cobalt content. In the case of massive sulphides the precious metals gold and silver and trace metals such as indium, tellurium, germanium, bismuth, cobalt and selenium are of particular interest in addition to the non-ferrous metals (copper, zinc and lead).

Ocean habitats

The precise impacts of deep-sea mining on the ecosystems of the seabed and throughout the water column are still largely unknown. The Federal Ministry of Education and Research (BMBF) is providing funding to an international pilot programme to investigate these impacts more closely and to provide reliable information about the actual consequences of deep-sea mining for ocean habitats. The research vessel "Sonne" is carrying out extensive studies of potential environmental impacts of deep-sea mining together with scientific teams from 12 other European countries.

International Seabed Authority

The research results are intended to help in the setting of high international standards for deep-sea mining that is environmentally compatible, sustainable and fair in terms of development policy. Thus they will provide the scientific basis for the "Mining Code" of the International Seabed Authority (ISA) which regulates prospecting and exploration and the future extraction of marine mineral resources. While the Authority has adopted rules for the prospecting and exploration of the mineral resources it has not yet done so for the mining of those resources. The ISA bodies are just starting work on this.

They are looking at how marine resources can be mined in an ecologically responsible way. The results of the planned project will provide a significant input for this. The participating countries will provide a combined total of more than 6 million euros for the work of the scientists involved.