The proposed methodology consists of simultaneously analysing the concentration variation of solute pairs during a storm event by plotting the concentration variation of one solute against the variation of another solute. This can reveal whether two or more end-members contribute to streamflow during a storm event. Furthermore, the variation of the solute ratios during the events can indicate which catchment processes are dominant and which are negligible.

Monitoring agricultural drainage flow in irrigated areas is key to water and soil management. In this paper, four simple drainage models are evaluated on two irrigated sub-basins where drainage flow is measured daily. The evaluation of their precision shows that they simulate drainage very well when calibrated with drainage data and that one of them is slightly better. The evaluation of their accuracy shows that only one model can provide rough drainage estimates without calibration data.

In the last decade, the development of on-site field laboratories to measure water chemistry at sub-hourly measurement intervals drastically advanced while there is no litterature that provide detailed technical, organisational and operational guidelines in running such equipments. Based on our experiences of running three French field laboratories over seven years, we share the difficulties we encountered and the procedures we used to identify and eliminate their causes.

The hydrological subsurface drainage model SIDRA-RU is assessed at the French national scale, using a unique database representing the large majority of the French drained areas. The model is evaluated following its capacity to simulate the drainage discharge variability and the annual drained water balance. Eventually, the temporal robustness of SIDRA-RU is assessed to demonstrate the utility of this model as a long-term management tool.