Environmental Work in the German License Area

Carsten Rühlemann, Marco Blöthe, Thomas Kuhn, Axel SchippersFederal 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 KastenAlfred Wegener Institute for Polar and Marine Research (AWI)

Aude PicardMax Planck Institute for Marine Microbiology

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, O2, Chl α (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.)

HawaiiLos Angeles

Honolulu

San Francisco

Mn nodule belt1250 nm

1200 nm

Location of the German License Area

Manzanillo

900 nm

Area West

Area East

SWATH ship:(small waterplanearea twin hull)

First two Exploration Cruises: R/V Kilo Moana

Oct/Nov 2008and 2009

Third Exploration Cruise with R/V Sonne

April/May 2010

► 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

Bathymetry of Area East

Hydroacustic signal amplitude: provides information about seafloor properties

Backscatter Strength

Plate Tectonic Drift (53 Ma to Present)

Present-day equatorial high productivity zone

Oceanography

► Physical oceanography: 4 CTD deployments (T, S, O2, Chl α), 3 in Area E, 1 in Area W

► Chemical oceanography: water column samples at 2 CTD stations (5 – 4350 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)

CTD Stations in Oct/Nov 2008

HawaiiLos Angeles

Honolulu

San Francisco

Manzanillo

CTD West CTD East

SBE 911 plus CTD profiler attached to a Sea Bird SBE 32 carrousel water samplerSBE 43 oxygen Clark-sensor with Teflon membrane, twenty four 10 L Niskin-bottles

SBE 911 plus

7x West

Bottom waterT: 1.5°CO2: 3.2 ml/l

100-700 m: O2 minimum

100m:Chl αmax.

Surface Chlorophyll Concentration in Nov 2008

NASA (http://oceancolor.gsfc.nasa.gov/cgi/l3)

Los Angeles

Honolulu

San Francisco

0.05 0.1

CTD Stations in Area East in Nov 2010

40 km

N

SO205-01CTD

SO205-21CTD

CTDs: Area East

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, sidescan sonar) (BGR)

► Gaps: particulate matter flux (sediment trap deployments)

Sediment Shear Strength (Area East)

25 box cores

Area W: 7.3 kPa in 10-40 cm (7 box cores)

Sediment Core (14 m): XRF Analysis with Core Scanner

Calcium

Manganese

Iron

Copper

Nickel

Barium

Chlorins

calcareous ooze

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400

Core depth (cm)0

20

40

60

Ligh

tnes

s L*

Chl

orin

s

0.0

10,000.0

20,000.0

30,000.0

Ba

Inte

nsity

500

750

1000

1250

1500

Ni I

nten

sity250

500

750

1000

1250

Cu

Inte

nsity

50,000

150,000

250,000

350,000

Fe In

tens

ity

0

20,000

40,000

60,000

80,000

100,000

Mn

Inte

nsity

0

200,000

400,000

600,000

800,000

1,000,000

Ca

Inte

nsity

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400

high

low

SO205-14KL

Lightness

Quat./Plio.siliceous clay (1mm/ka) no

dule

s Hiatus (16-3.6 Ma)

middle Miocene?reddish brown clay

Total Organic Carbon Content (upper 40 cm)

0 0.2 0.4 0.6

Corg (%)

40

30

20

10

0

Dep

th (c

mbs

f)

Area WestArea East

West East

Sedi

men

t dep

th(c

m)

Surface Water Chlorophyll (mg/m³)

Area WestArea East

0.1-0.2 mg/m³

West East0.07-0.08 mg/m³

2200 km

Strong backscatter,high topography –vulcanic seamounts

Strong backscatter,low topography –Mn nodule field?

Bathymetry Backscatter signal20 km

Backscatter Strength

Nodule Size Distribution at Medium / High Backscatter

medium / lowbackscatter(light gray)

highbackscatter

(medium gray)

0

0.1

0.2

0.3

0.4

Rel

ativ

e fre

quen

cy

0 2 4 6 8 10 12 14 16 18 20

Maximum diameter (cm)

Backscatter values: 114-138- 69 nodules per box core- 19 kg/m²- Mn/Fe: 4.3- Ni+Cu: 2.6%

12 KGs, 824 nodules

0

0.1

0.2

0.3

0.4

0 2 4 6 8 10 12 14 16 18 20

Backscatter values: 69-90- 239 nodules per box core- 16 kg/m²- Mn/Fe: 3.4- Ni+Cu: 2.4% 12 KGs, 2862 nodules

SO205-24KG

SO205-44KG

12 Locations with high backscatter12 Locations with medium/low backscatter

Standard Deviation of Nodule Size vs Backscatter

60 80 100 120 140

Backscatter gray value

0

1

2

3

4

Sta

ndar

d de

v. (σ

) of n

odul

e si

ze

R2 = 0.35

standard dev.

Porewater Geochemistry

► Pore water sampling: 13 MUCs, 8 long sediment cores (6 – 14 m) with rhizon samplers

► Shipboard / home lab analyses:O2 with Clark-type oxygen electrodes directly in sediment

Eh, pH (micro electrodes), alkalinity (titration), silica

Anions: Fe2+, NO2

-, NO3-, PO4

3-, SO42-, Cl- (photometrically)

Cations: Ca, Mg, Sr, K, Ba, S, Mn, Si, B, Li (ICP-AES and AAS)

Marine Geochemistry

Marine GeochemistryPore Water O2 Conc. in MUC Sediment

06MUC/15KLno nodules

05MUC/14KL12.8 kg/m²

Sedi

men

t dep

th(µ

m)

Marine GeochemistryPore Water Geochemistry

15KL

14KL

Backscatter

15KL: low backscatter (no nodules) 14KL: medium backscatter (12.8 kg/m²)

Locations of long sediment cores

Porenwasserprofile KL 14

► medium backscatter, 12.8 kg/m² nodule abundance► low Mn2+ conc. (<0.5 µmol/l) and no nitrate reduction detected

oxic

suboxic

Sedi

men

t dep

th(m

)

Marine GeochemistryPore Water Geochem: Piston Core 14KL

Mewes, Kasten et al. (in prep.)

Surface

0 20 40 60Mn (µmol/l)

16

12

8

4

00 20 40 60 80 100

O2 (µmol/l)

16

12

8

4

0

0 20 40 60NO3 (µmol/l)

16

12

8

4

0

2+(µmol/l)

► low backscatter, no nodules or small nodules► increasing Mn2+ and decreasing NO3 conc. under suboxic conditions► Mn(IV)O2 becomes reduced to Mn2+

Marine Geochemistry

Surface

Mewes, Kasten et al. (in prep.)

0 20 40 60 80 100O2 (µmol/l)

16

12

8

4

0

0 20 40 60NO3 (µmol/l)

16

12

8

4

0

0 20 40 60Mn (µmol/l)

16

12

8

4

0

oxic

suboxic

Nitratereduction

Manganesereduction

2+(µmol/l)

Sedi

men

t dep

th(m

)Pore Water Geochem: Piston Core 15KL

Composition and Diversity of the Benthic Community

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. deep-sea 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 faunalassemblage and diversity

German Center for Marine Biodiversity ResearchPedro Martínez-Arbizu, Annika Tiltack, Sabine Schückel, Ulrike Schückel,Maria Miljutina

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 sledgeMacrofauna (1 mm - 4 cm) → box corerMeiofauna (32 µm - 1 mm) → multicorer

Locations of Photosledge Deployments

Photo Sledge: Megafauna

Photo Sledge: Megafauna

? Peniagone leander (Pawson & Foell, 1986) (length 22-23 cm)

Locations of Epibenthos Sledge Deployments

Taxonomic Groups in Epibenthos Sledge Samples

Protozoa:ForaminiferaKomokiaceaXenophyophora

Porifera:Hexactinelida

Nematoda

Crustaceans:Peracarida:

IsopodaAmphipodaCumaceaTanaidacea

Maxillopoda:CopepodaOstracodaTantulocarida

Mollusca:AplacophoraPolyplacophoraBivalviaGastropoda

Bryozoa

Cnidaria:HydrozoaAnthozoa

Annelida:Polychaeta

Echinodermata:OphiurideaEchinoidea

most commontaxa

„so far no differencesbetween EBS sitescould be detected“

Cumacea

Tanaidacea

Amphipoda

Tanaidacea

Isopoda

Cumacea

Copepoda Calanoida IsopodaDesmosomatidae

Selected Species Sampled in Epibenthos Sledge

Porifera HexactinenelidaOphiuridae

MolluscaAplacophora Mollusca Bivalvia

Komokiacea Lana

KomokiaceaSeptuma

Biodiversity Studies15 multicorer + 20 box corer

sample locations

total abundance

0

2

4

6

8

10

12

14

10 11 17 18 24 27 29 32 34 41 44 45 49 53 56 58 62 63 68

10 KG

29 KG

49 KG

53 KG

Organisms on Nodules: Species Abundance (separated animals)N

umbe

rof s

peci

es/ 0

.25

m²

Box core #

14

3

7

3PolychaetaPoriferaBryozoaEchinodermata

► sessile: filtrating organisms (filter feeder) dominate

► mobile: deposit und subsurface deposit feeder

Proportions of Currently Identified Species on Major Group Level

Box coresseperated animals

Box Core Sample: Komokis on Nodule

Box Core Samples: Bryozoaundefined specimen of Bryozoa

Maldanidae species 1

Maldanidae species 2

habitation tubeOphelina sp. Serpulidae

Spirorbinae(found in 9 box cores)

Phyllodocidae

tube builders, sessilemobile

Terebellidae

Box Core Samples: Polychaeta

habitation tube

Molecular-Genetic Analyses

PCR Analysis: Amplification of Gene Fragments COI and 28s

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

Percentage of Successful Amplifications of Selected Genes

Macrofauna(95 individuals) (240 individuals)

► 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 areaswith 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

Main Biodiversity Results (preliminary onboard observations)

Microbiology: Main Objectives

► Evaluation of microbiota living on/in nodules and in sediment

► Identification of microorganisms possibly involved in Mn nodule formation

A. Kappler et al., Geobiology (2005), 3, 235–245

Example:Fe(III)-precipitates formedaround cells by the Fe(II)-oxidizing bacterium BoFeN1

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 reducersCARD-FISH method

strain BoFeN1

XY

Bacteria Archaea(1) Rim 3.05 x 108 1.14 x 108

(2) Hydrogenetic 0.27 x 108 0.01 x 108

(3) Diagenetic 1.72 x 108 0.10 x 108

(4) Nodule core 1.81 x 108 0.30 x 108

(5)  Sediment 1.18 x 108 no data

Manganesenodule

Microbiology: Bacteria Abundances on/in Nodules

1

2

3

45

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)

Germanlicense area

NODBIO Project: French – German Cooperation

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

Frenchlicense area

German Environmental Impact Studies (Peru Basin)

►DISCOL (1989-1993): University Hamburg (Biology)

► TUSCH / ATESEPP (1993-1997): BGR, Geomar, AWI, UnivBerlin, Univ Hamburg, Univ Hannover (DISCOL extended byGeology, Geochemistry, Oceanography)

► Five research cruises from 1989 to 1997(4-8 weeks)

► >100 publications including„Environmental Imapct Studies for theMining of Polymetallic nodules from theDeep Sea“ in Deep-Sea Research

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

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 miningprocess 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 bestudied on scales of kilometers by international cooperation)

► Species living on the abyssal plains are probably widelydistributed

Thiel et al. (2005), Mar. Georesour. Geotechnol., 23: 209