Environmental Work in the German License Area

Transcription

1 Environmental Work in the German License Area Carsten Rühlemann, Marco Blöthe, Thomas Kuhn, Axel Schippers Federal Institute for Geosciences and Natural Resources (BGR) Pedro Martínez-Arbizu, Annika Tiltack, Sabine Schückel, Ulrike Schückel, Maria Miljutina German Center for Marine Biodiversity Research (DZMB) Konstantin Mewes, Sabine Kasten Alfred Wegener Institute for Polar and Marine Research (AWI) Aude Picard Max Planck Institute for Marine Microbiology

2 Environmental Work in the German License Area Contract with ISA in July 2006 (75,000 km², two subareas) Three cruises in Oct/Nov 2008 and 2009, April/May 2010 Bathymetry and backscatter data (completed) Magnetic profiling: paleogeographic reconstruction Water column T, S, O 2, Chl a (4 stations), water sampling (2x) Sediment properties and nodule facies (45 box cores) Pore water geochemistry (13 MUCs, 8 long sediment cores) Biodiversity (5 EBS, 20 box cores, 15 MUCs) Microbiology (14 MUCs, 13 box cores, 7 long cores 236 nod.)

3 Location of the German License Area Hawaii San Francisco Los Angeles Honolulu Manzanillo Area East Area West

4 First two Exploration Cruises: R/V Kilo Moana Oct/Nov 2008 and 2009 SWATH ship: (small waterplane area twin hull)

5 Third Exploration Cruise with R/V Sonne April/May 2010

6 Bathymetry of Area East 58,000 km², avg. Depth = 4200 m hull-mounted Simrad EM 120 multibeam echosounder 9 knots speed, 15 km swath width 125 x 125 m grid resolution ~80% low-relief areas, N-S horst / graben structures seamounts: 2 >2000 m, 6 >1000 m, 307 >100 m fracture zones

7 Area East Backscatter Strength Hydroacustic signal amplitude Information about seafloor properties

8 Plate Tectonic Drift (53 Ma to Present) Present-day equatorial high productivity zone

9 Oceanography Physical oceanography: 4 CTD deployments (T, S, O 2, Chl a), 3 in Area E, 1 in Area W Chemical oceanography: water column samples at 2 CTD stations ( m) in Area E bottom water samples at 9 MUC stations in Area E Lab analyses: radiogenic isotope analyses (IFM-Geomar) trace elements (AWI) respiration rate measurements (MPI Microbiology) microbiology/incubation experiments (BGR) Gaps: current measurements (ADCP moorings, numerical modeling incl. particle transport) seasonality (2-4 cruises per year)

10 CTD Stations in Oct/Nov 2008 Hawaii San Francisco Los Angeles Honolulu Manzanillo CTD West CTD East SBE 911 plus SBE 911 plus CTD profiler attached to a Sea Bird SBE 32 carrousel water sampler SBE 43 oxygen Clark-sensor with Teflon membrane, twenty four 10 L Niskin-bottles

11 100m: Chl a max m: O 2 minimum 7x West Bottom water T: 1.5 C O 2 : 3.2 ml/l

12 Surface Chlorophyll Concentration in Nov 2008 San Francisco Los Angeles Honolulu NASA (

13 CTD Stations in Area East in Nov 2010 N 40 km SO205-21CTD SO205-01CTD

14 CTDs: Area East

15 Sediment Properties and Nodule Facies Shear strength: 46 box cores (30 in Area East, 6 in Area West), 8 long sediment cores Sediment grain size: box core samples (BGR, to be carried out) Pore water chemistry: 25 box cores, 13 MUCs, 8 long sediment cores (BGR, AWI) Solid phase geochemistry: element concentrations (XRF core scanner) (BGR, AWI) Organic matter: TOC, TN (box cores and long sediment cores) (BGR) Nodules facies: 46 box cores (size distribution, metal conc.), backscatter (EM 120, side scan sonar) (BGR) Gaps: particulate matter flux (sediment trap deployments)

16 Seafloor Sampling Locations N OMI (Preussag): 196 stations ( ) metal conc., nodule abund. BGR: 40 box core stations ( ) Nodules: metal conc., abundance, size distribribution, Sediments: shear strength, phys. prop., micropal., microbiol., pore water chemistry, biodiversity Side scan sonar SSS

17 Sediment Shear Strength (Area East) 25 box cores Area W: 7.3 kpa in cm (7 box cores)

18 Sediment Core (14 m): XRF Analysis with Core Scanner SO205-14KL Quat./Plio. siliceous clay (1mm/ka) 80, Hiatus ( Ma) ,000, , ,000 middle Miocene? reddish brown clay 400, ,000 calcareous ooze Manganese 40,000 20, , , , , , , high 10, Ni Intensity 750 Chlorins Ba Intensity Cu Intensity 1250 Lightness L* Calcium 0 60,000 Fe Intensity Mn Intensity 100, Ca Intensity 100 nodules 0 Iron Copper Nickel Barium Chlorins low 40 Lightness 20 Core depth (cm)

19 Sediment Depth (cmbsf) depth (cm) Total Organic Carbon Content (upper 40 cm) Corg (%) Corg (%) West East Surface Water Chlorophyll (mg/m³) West mg/m³ 2200 km mg/m³ East 30 Area West Area East 40 Area West Area East

20 Backscatter Strength Bathymetry 20 km Backscatter signal Strong backscatter, high topography vulcanic seamounts Strong backscatter, low topography Mn nodule field?

21 Backscatter Strength 12 Locations with high backscatter 12 Locations with medium/low backscatter

22 Nodule Size Distribution at Medium / High Backscatter Relative frequency SO205-24KG 0.4 medium / low backscatter (light gray) Backscatter values: nodules per box core - 16 kg/m² - Mn/Fe: Ni+Cu: 2.4% 12 KGs, 2862 nodules high backscatter (medium gray) Backscatter values: nodules per box core - 19 kg/m² - Mn/Fe: Ni+Cu: 2.6% 12 KGs, 824 nodules SO205-44KG Maximum diameter (cm)

23 Standard Deviation of Nodule Size vs Backscatter Standard dev. ( of nodule size Arithmetic mean of nodule size 4 R 2 = standard dev Backscatter gray value

24 Porewater Geochemistry Marine Geochemistry Pore water sampling: 13 MUCs, 8 long sediment cores (6 14 m) with rhizon samplers Shipboard / home lab analyses: O 2 with Clark-type oxygen electrodes directly in sediment Eh, ph (micro electrodes), alkalinity (titration), silica Anions: Fe 2+, NO 2-, NO 3-, PO 3-4, SO 2-4, Cl - (photometrically) Cations: Ca, Mg, Sr, K, Ba, S, Mn, Si, B, Li (ICP-AES and AAS)

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26 Sediment depth (µm) Pore Water O 2 Conc. in MUC Sediment Marine Geochemistry 06MUC/15KL no nodules 05MUC/14KL 12.8 kg/m²

27 Pore Water Geochemistry Marine Geochemistry Backscatter 15KL 14KL Location of piston cores 14 KL and 15KL

28 Sediment depth (m) Depth (m) Depth (m) Pore Water Geochem: Piston Core 14KL Porenwasserprofile 14 KL KL KL KL Marine Geochemistry O2 (µmol/l) NO3 (µmol/l) Mn (µmol/l) O2 O2 (µmol/l) oxic 4 4 suboxic Surface medium backscatter, 12.8 kg/m² nodule abundance low Mn 2+ conc. (<0.5 µmol/l) and no nitrate reduction detected Mewes, Kasten et al. (in prep.)

29 Sediment depth (m) Depth (m) Depth (m) Pore Water 14 KL Geochem: Piston Core 15KL 14 KL Marine Geochemistry O2 (µmol/l) oxic NO3 (µmol/l) Mn Mn (µmol/l) O2 (µmol/l) suboxic Nitrate reduction Manganese reduction Surface low backscatter, no nodules or small nodules increasing Mn 2+ and decreasing NO 3 conc. under suboxic conditions Mn(IV)O 2 becomes reduced to Mn 2+ Mewes, Kasten et al. (in prep.)

30 Composition and Diversity of the Benthic Community German Center for Marine Biodiversity Research Pedro Martínez-Arbizu, Annika Tiltack, Sabine Schückel, Ulrike Schückel, Maria Miljutina General objectives Determine benthic communities and diversity in dependence of nodule facies (dense nodule abundance versus low abundance or nodule-free areas) Influence of topography on faunal assemblage and diversity (seamounts vs. deepsea plain) Comparison with own investigations in the French license area (Nodinaut project) and results from the KAPLAN project Influence of ocean surface bioproductivity (E-W, S-N gradients) on faunal assemblage and diversity

31 Sampling (OFOS, MUC, Box Cores, EBS) Photo sledge (OFOS): 5x video tracks, 2x tracks with high resolution photos 15x Multicorer (159 tubes in total): 66 samples (3-5 per station) for Meiofauna community (formol) 10 samples (1 per station) for vertical distribution (1 cm slices) (formol) 15 samples (at least 1 per station) for DNA studies (DESS) 20x box corer: 40 samples (Ethanol), single animals on nodules (DESS) 5x EBS 10 Macrofauna Proben (Ethanol), 9 Meiofauna (DESS) Megafauna (>4 cm, detectable on photos) photo sledge Macrofauna (1 mm - 4 cm) box corer Meiofauna (32 µm - 1 mm) multicorer

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33 Photo Sledge: Megafauna

34 Photo Sledge: Megafauna? Peniagone leander (Pawson & Foell, 1986) (length cm)

35 Locations of Epibenthos Sledge Deployments

36 Taxonomic Groups in Epibenthos Sledge Samples Protozoa: Foraminifera Komokiacea Xenophyophora Porifera: Hexactinelida Nematoda Crustaceans: Peracarida: Isopoda Amphipoda Cumacea Tanaidacea Maxillopoda: Copepoda Ostracoda Tantulocarida Mollusca: Aplacophora Polyplacophora Bivalvia Gastropoda Bryozoa Cnidaria: Hydrozoa Anthozoa Annelida: Polychaeta Echinodermata: Ophiuridea Echinoidea most common taxa so far no differences between EBS sites could be detected

37 Selected Species Sampled in Epibenthos Sledge Tanaidacea Cumacea Ophiuridae Porifera Hexactinenelida Amphipoda Tanaidacea Mollusca Aplacophora Mollusca Bivalvia Isopoda Cumacea Komokiacea Lana Komokiacea Septuma Copepoda Calanoida Isopoda Desmosomatidae

38 Biodiversity Studies 15 multicorer + 20 box corer sample locations Multicorer Box corer

39 Number abundanc of species e (0.25 / 0.25 m²) m² Organisms on Nodules: Species Abundance (separated animals) total abundanc e Box core # K G - S tations 10 KG 49 KG 29 KG 53 KG

40 Proportions of Currently Identified Species on Major Group Level Box cores seperated animals Polychaeta Porifera Bryozoa Echinodermata sessile: filtrating organisms (filter feeder) dominate mobile: deposit und subsurface deposit feeder

41 Box Core Sample: Komokis on Nodule

42 Box Core Samples: Bryozoa undefined specimen of Bryozoa

43 Box Core Samples: Polychaeta mobile Maldanidae species 1 tube builders, sessile habitation tube Terebellidae Phyllodocidae Maldanidae species 2 Ophelina sp. habitation tube Spirorbinae (found in 9 box cores) Serpulidae

44 Molecular-Genetic Analyses Main objectives Gene flow: determination of population size, similarities in species assemblage and genetic similarities Collection of molecular data of all organisms (Barcoding) Methods Amplification of Cytochrome oxidase subunit I (COI), 12 S and 28 S ribosomal DNA PCR Analysis: Amplification of Gene Fragments COI and 28s

45 Percentage of Successful Amplifications of Selected Genes Macrofauna (95 individuals) (240 individuals)

46 Main Biodiversity Results (preliminary onboard observations) Most common taxa in EBS: Isopoda, Polychaeta, Copepoda, Tanaidacea Macrofauna in sediment (0-10 cm) dominated by polychaetes, tanaids, cumaceans, amphipods, bivalves Higher abundance of sessile macrofauna organisms in areas with small-sized nodules Megafauna in German license area strongly resembles those of the French license area Megafauna on the seamounts in the license area is similar to the benthic community of the deep-sea plains

47 Microbiology: Main Objectives Evaluation of microbiota living on/in nodules and in sediment Identification of microorganisms possibly involved in Mn nodule formation Example: Fe(III)-precipitates formed around cells by the Fe(II)- oxidizing bacterium BoFeN1 A. Kappler et al., Geobiology (2005), 3,

48 Microbiology: Samples and Lab Analyses 236 nodule samples (111 at -20 C, 125 in sterile sea water at 4 C) 264 sediment samples from 13 MUCs, 12 box cores and 7 long sediment cores (in formaldehyde-pbs solution at -20 C) Numbers of living bacteria / archaea by CARD-FISH Numbers of different groups of prokaryotes by Q-PCR DNA extraction of - hydrogenetic/diagenetic nodules - sediment DNA analysis by - DGGE (density gradient gel electrophoresis) - Clone data base Cultivation of Mn oxidizers and reducers strain BoFeN1 CARD-FISH method

49 Microbiology Sample Locations in Area East 13 MUCs 12 box cores 7 long sediment cores

50 Microbiology: Bacteria Abundances on/in Nodules 2 5 Manganese nodule 4 Y X 1 Bacteria Archaea (1) Rim 3.05 x x 10 8 (2) Hydrogenetic 0.27 x x 10 8 (3) Diagenetic 1.72 x x 10 8 (4) Nodule core 1.81 x x 10 8 (5) Sediment 1.18 x 10 8 no data 3

51 National and International Cooperation German Center for Marine Biodiversity Research (DZMB) Alfred Wegener Institute for Polar and Marine Research (AWI) Leibniz Institute of Marine Sciences (IFM-Geomar) Max Planck Institute for Marine Microbiology (MPI) French Research Institute for Exploitation of the Sea (Ifremer)

52 NODBIO Project: French German Cooperation French license area German license area General objectives (joint cruise planned for 2012) Lénaick Menot Description and understanding of fauna/habitat relationships at regional and local scales Evaluation of distribution of benthic species Quantification of connectivity between populations of the two areas

53 German Environmental Impact Studies (Peru Basin) TUSCH (Deep-Sea Environment Protection) DISCOL (Disturbance and Recolonization Experiment) ATESEPP (Effects of Technical Interventions into the Ecosystem of the Deep Sea in the Southeast Pacific Ocean off Peru DISCOL ( ): University Hamburg (Biology) TUSCH / ATESEPP ( ): BGR, Geomar, AWI, Univ Berlin, Univ Hamburg, Univ Hannover (DISCOL extended by Geology, Geochemistry, Oceanography) Five research cruises from 1989 to 1997 (4-8 weeks) >100 publications including Environmental Imapct Studies for the Mining of Polymetallic nodules from the Deep Sea in Deep-Sea Research

54 Major Conclusions of DISCOL / TUSCH Seven years after seafloor disturbance the benthic community structure seemed to be quite similar to that before disturburb. (based on individual counts and taxonomic investigations) Hard bottom fauna did not return Experiments: most of the sediment suspended during mining process should resettle at distances of up to 2 km Impact evaluation is difficult because of high numbers of undescribed and rare species (species distribution need to be studied on scales of kilometers by international cooperation) Species living on the abyssal plains are probably widely distributed Thiel et al. (2005), Mar. Georesour. Geotechnol., 23: 209