ABSTRACT:

This dataset comprises two years of 15-minute measurements of humic-like fluorescence (HLF; Ex 325 nm/Em 470 nm) and tryptophan-like fluorescence (TLF; Ex 275 nm/Em 350 nm), along with additional water quality variables (DO, turbidity, EC) and hydrometeorological data (water level and rainfall) collected from an urban headwater in Birmingham, UK

ABSTRACT:

In June 2023, the UK experienced its driest and warmest June on record. During this exceptional period, our long-term in-situ monitoring program captured an unprecedented riverine hypoxia event at four sites (25–5000 km²) with varied land use. A series of convective thunderstorms following prolonged warm and dry conditions led to sharp dissolved oxygen depletions, which our in-situ fluorescence measurements and ancillary laboratory analyses revealed riverine hypoxia across sites were closely associated with the labile fraction of dissolved organic matter (LDOM) rather than bulk dissolved organic carbon (DOC) and humic materials.

ABSTRACT:

In-situ high frequency monitoring of water quality variables was conducted from October 2021 to October 2022 in the Bourn Brook, Birmingham, UK. Humic-like fluorescence (HLF, excitation wavelength: 325 nm, emission wavelength: 470 nm) and Tryptophan-like fluorescence (TLF, excitation wavelength: 275 nm, emission wavelength: 350 nm) were monitored using a Manta 2 multiparameter sonde (Eureka, TX, USA), which was also equipped with sensors for ancillary measurements of electric conductvity, turbidity and water temperature. Additionally, a pressure transducer (CS420-L, Druck Inc., Billerica, Massachusetts) was installed in an adjacent stilling well for water level measurements. The Manta 2 was internally configured to log a measurement every 5 minutes, while the pressure transducer was controlled by a CR1000X datalogger (Campbell Scientific, Logan, USA) logging at 1 min intervals. Both these devices were powered by 12V batteries. In addition, meteorological variables (precipitation and air temperature) were also collected from a weather station operated by the University of Birmingham, located ~1 km from our water quality monitoring station.