| The multicorer is being recovered. up to 16 tubes may be used to sample both sediment and genuine bottom water. |  |
| The samples are enclosed between two shutters which are securely closed when the device is lifted |  |
| The sediment is kept in place by a titanium or stainless steel shovel, the shutters are removed and replaced by rubber stoppers |  |
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the closed tubes are carefully stored in a tube stand The multicorer is the preferred sampling device for investigation of the water-sediment interface, flux studies and high resolution measurements in the uppermost part of the sediment. |
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In the cool lab the lower rubber stopper is replaced by a piston and the upper end of the tube is fixed in a hole in the glove box bottom. After bottom water is sampled sediment pH and Eh are determined. The sediment may then be pushed out layer by layer, cut and porewater is extracted using the pressure filtration device |
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