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 proposed methodology consists of simultaneously analysing the concentration variation of any two solutes during a storm event, by plotting the concentration variation of one solute against the variation of another solute. For each solute pair and each storm event, this methodology can reveal, whether only two or whether more than two end-members contribute to the stream flow during a storm event. In consequence, conclusions can be drawn about hydro-biogeochemical processes in catchments.

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.

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.