


Characterisation of DON and its potential bioavailability in the Peel-Harvey Catchment
Dissolved organic N (DON) in aquatic systems is made up of diverse compounds (e.g., amino acids, urea, humic substances) with varying reactivity, bioavailability, and concentration, which, along with inorganic N (nitrate, nitrite and ammonium), supports the growth of phytoplankton, bacteria and macrophytes. As such, DON may be an important, but often overlooked, component of the available N pool in aquatic systems which may preferentially support the growth of particular microbial taxa, including nuisance and toxic algal blooms.
In the Peel- Harvey catchment, DON comprises the highest proportion of total dissolved N. However, there is currently limited understanding of the composition of DON in this system, as well as its potential bioavailability.
Client:
Department of Water & Environmental Regulation
Research Objective:
Assess the potential bioavailability of DON at key sites within the Peel-Harvey Catchment.
Research Outcomes:
1. Improved understanding of the importance of DON for water quality management in the Peel-Harvey Catchment.
2. Assessment of the effectiveness of using simple fluorescence-based measurements of DOM to characterise DON.
3. Assessment of the potential bioavailability of DON within key sites of the Peel-Harvey Catchment.