Shifts in discharge-concentration relationships as a small catchment recover from severe drought

This paper provides evidence of the recovery of a small, moorland catchment to a severe drought, the most extreme on record in the UK. We present a detailed water quality time series for the post-drought recovery period, from the first significant storm event at the end of the drought through three very wet months during which time the catchment fully wetted up. High-frequency observations were obtained using pump water samplers, at 15-min intervals for storm events and 2 hourly at other times. There are significant shifts in discharge-concentration response as the catchment wets up; initial behaviour is very different to later storms. Extreme drought may become more common in a warmer world, so it is increasingly important to understand water quality response during and after such episodes, if their impact on water resources and in-stream ecology is to be better anticipated.