ARDEX is funded by

The ARDEX scientific objectives are to:

1) Characterize the CDOM in fresh, brackish and saltwater environments in the Mackenzie River, and Delta via bio-optical and chemical analysis;

2) Determine and model the effects of CDOM on spectral UV and PAR penetration;

3) Assess the loss of CDOM via photochemical degradation to CO and to CO2;

4) Determine the rates of microbial mineralisation of DOM and CDOM. This and objectives 3 and 7 have major implications for our assessment of how much of Canada's tundra and boreal carbon stocks may be mobilised and converted to greenhouse gases and ventilated to the atmosphere via riverine transport to the Arctic Ocean;

5) Estimate the production of CDOM by zooplankton (sloppy feeding, ejestion and excretion) in part using novel fluorescence techniques;

6) Evaluate biogeochemical characteristics of the fresh, brackish and saltwater components of the system, including reactive nutrients, CDOM and major ions, and chemical transformations across the FSTZ.

7) Determine the spatial and temporal variations in pCO2 and pO2 in the river, transition zone and offshore waters.

8) Evaluate the relative importance of autochthonous versus allochthonous materials as the source of organic carbon in the metazoan food web, and variations across the freshwater-saltwater gradient.