UK ECN site. Loch Dee forms the headwaters of the River Dee and has a surface area of 1km2, with a total catchment area of 15.6km2. It has 3 principal sub-catchments, the Dargall Lane, the White Laggan and the Black Laggan Burns (30% planted with sitka spruce), and the Green Burn with 67% of its area planted with sitka spruce. It has highly variable rainfall with dry periods in spring and summer a predominant feature. Average rainfall is moderately acidic (pH 4.6 - 4.9) and the chemistry dominated by salts of marine origin, mainly Na+, CL- and SO4; for most samples the concentration ratios between the ions match those of sea water. The topography and land use affect the flows in the sub-catchments giving a wide dynamic range of flows in the main tributaries. The Dargall Lane is steep and peaty, whereas the other two sub-catchments are afforested. As with many of the catchments in the Galloway area the geology comprises igneous rocks such as granite, with thin overlying soils giving poor neutralising and buffering capacities.