Understanding the impacts of deep-sea mining on the marine environment Matthias Haeckel GEOMAR Helmholtz Centre for Ocean Research Kiel Science-Policy Workshop Knowledge-Based Governance of Deep-Sea Resources
Introduction Impacts of polymetallic nodule mining Removal of nodules + top ~10 cm of seafloor Generation of sediment plume at the seafloor resettling downstream Discharge of sediment tailings from surface platform / riser pipe Oebius et al. (2001) DSR II 48 Effects Removal and burial of benthic fauna, clogging of filter feeder s feeding apparatuses Change in sediment characteristics and processes => Impact on deep sea ecosystem structure and functioning TUSCH, 1996 KIOST, 2013
JPIOceans Pilot Action MiningImpact Overall goal Assessing the impact of nodule mining on deep sea ecosystems Status of disturbed ecosystems in the DISCOL Experimental Area (SE Pacific) Implications for future nodule mining in the Clarion Clipperton Zone (NE Pacific) CCZ DISCOL
Sampling strategy in CCZ => Comparing different areas across a productivity gradient APEI 3 Seamounts 2 Sites 60 French Area Seamounts Belgian Area Tracks Seamounts High 2 SitesNodule densitytracks 2 Sites High/low High 40 Low IOM Area BIE revisited Tracks 1 control site 20 High/low 0 Individuals per 0.25 m² German Area Seamounts Tracks 2 Sites BGR POC IOM GSR Ifremer APEI Martinez et al. 2015
Sampling strategy in CCZ Revisiting old disturbance tracks and comparing seamounts & nodule fields German, EBS, 0 years IOM BIE, 20 years French, Dredge / OMCO track, 37 years
Sampling strategy at DISCOL Comparing sites inside + outside 26-year old plough marks & reference areas The plough harrow (1989) Disturbance track (0 years) Thiel & Schriever (1990) Ambio 19 Disturbance track (7 years) Disturbance track (26 years) Thiel et al. (2001) DSR II 48 AUV Abyss, GEOMAR
Sampling strategy at DISCOL
Sampling strategy at DISCOL Seafloor & habitat mapping Photo mosaicking Koeser, GEOMAR
Sampling strategy at DISCOL State of the art methodology & technology Habitat mapping with AUV & ROV Targeted sampling of different habitats In situ process studies with autonomous instruments in situ experimentation with ROV In situ ecotox experiment Micro habitat sampling In situ benthic flux studies
Sediment plume experiments in CCZ + DISCOL Understand fate of particles and effective footprint in space and time Demonstrate monitoring methods EBS plume creation (plume after 30 min) ROV plume creation (plume after 30 min) EBS plume after 60 min (photo) EBS plume detection (ADCP)
Conclusion Summary Appropriate technology & methodology to monitor & assess mining impacts is available, but requires some effort Effects of disturbances on nodule ecosystems last for many decades and include all ecosystem compartments: fauna of all size classes, biogeochemical ecosystem functions Effect of mining plumes (suspended & dissolved matter) is currently the biggest unknown Nodule ecosystems harbor a highly diverse fauna High spatial variability in faunal communities Conservation areas need to match characteristics of mined areas (e.g., productivity, nodule coverage) => suitability of APEIs? Recommendations / future work Minimizing the impact: strategies for spatial planning of mining activities, establishment of marine protected areas, low-impact mining equipment Development and testing of means of restoration
MiningImpact Ecological Aspects of Deep-Sea Mining Acknowledgements Captains and crews of RV SONNE (SO239 & SO242) All project partners and funding organizations: Belgium: UGent, RBINS France: IFREMER Germany: GEOMAR, MPI, SGN, JUB, UBremen, AWI, BGR, UBielefed Italy: Conisma Norway: IRIS, NTNU, UiB Poland: ULodz, USzczecin Portugal: UAveiro, IMAR Romania: Geoecomar Sweden: UGothenburg The Netherlands: NIOZ United Kingdom: NOCS/NERC, NHM, USOU