RV SONNE Cruise - SO242-1 and SO242-2

Duration: 29 days (July 28 - August 25 2015) and 35 days (August 28- October 1 2015)

In the 70s and 80s the idea of using Mn-nodules as a metal resource created commercial but also scientific interest in the deep sea ecosystem. Inter alia the scientific and industrial cumminity was interested in the question, how commercial mining might impact this unknown realm?

Scientist in Germany thought about a strategy to investigate how to simulate such an impact to see how quickly the deep sea environment might recover from the disturbance. To investigate this, they choose an area 7° south of the equator offshore Peru to perform a larger scale disturbance experiment. Subsequently, they monitored the decolonization of the seafloor over 7 years. The experiment itself happened in 1989, with the last investigation in 1996 during SO106. Now, 26 years later (during SO242 with the ‘New' SONNE) the same area will be investigated with much more sophisticated technology than was available before.

The international team will consist of scientists and technicians from Belgium, Germany, Portugal, Netherlands, Norway and the United Kingdom.

 

 

 

 

Objectives:

  1. Habitat characteristics: Detailed investigations of sampling / measurement / experimentation sites;Large scale mapping performed during leg 1
  2. Benthic and hyperbenthic community characteristics: Focus on small size classes (micro‐, meiofauna) and megafauna; Macrofauna addressed at leg 1
  3. (Bio‐) geochemical processes and rates: Focus on upper sediment layer and in situ measurements; sampling of deeper sediment layers at leg 1
  4. Benthic foodwebs & energy transfer: Fate of fresh organic matter (remineralization, incorporation, transfer)
  5. Bioaccumulation and Ecotoxicology: Incorporation of contaminants, physiological/ molecular responses

 

Technology used during the cruise:

Leg 1 aims for very detailed acoustic and visual mapping, using the AUV Abyss. Sediment samples will be taken with TV-MUC and GC, to investigate the geochemical differences and long term changes between disturbed and undisturbed area and the comparison of the new findings with previous data.

Biological sampling with the TV-guided multi-corer (TV-MUC), box corer and EBS as well as detailed image analyses of the living fauna will be used to compare the ‘state of the environment' and the recovery compared to the findings 26 years ago.

 

During Leg-2, the ROV will be the main working equipment for highly targeted sampling and in-situ experiment at the seafloor. The international team will consist of scientists and technicians from Belgium, Germany, Portugal, Netherlands, Norway and the United Kingdom.