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	Experimental Facilities		Mesocoms to investigate sediment water interactions Mesocosms are round 5 mm thick Plixiglass chambers (50  cm height x 24 cm diameter) (Fig 1) with a volume of    23 L. Three 2 cm cut-outs on the top of the mesocosm allow for connection to a water reservoir and sampling port. Mesocosms are used for sediment incubations as well as for macrophyte incubations (Figure 2). Fig. 1 Schematic and photo of mesocom to be used for measuring denitrification, with water column and sediment layer.   Sediment Sampling Sediment sampling is done by inserting the mesocosm 10-15cm into the sediment. After pushing the mesocosm into the sediment, all three holes are closed with silicone stoppers and a thinner Plexiglass plate cuts the bottom of the core.  This plate is left in the bottom of the mesocosm and held by hand when the mesocosm is lifted to prevent the sediment from falling out. The bottom plate of 5mm thick Plexiglass is attached to the base of the mesocosm and screwed in place to close the mesocosm and secure the sediment and overlying water column in gas tight in situ conditions. A small water pool is situation on the top of the mesocosm (not shown) for water sampling throughout the incubation period.  In the laboratory, the mesocosms are connected to a 45L reservoir of filtered water from the sampling location in order to create flow through conditions.    Fig. 2. Mesocosms used for macrophyte incubation.
	BioFRAMES  Biochemical Functions: Research and Management in Ecosystems at multiple Scales
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